Topic: AM - Additive Manufacturing
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ANALYSIS OF THE MECHANICAL AND THERMAL PROPERTIES OF A POLYMERIC MATRIX OF TRIPROPYLENE GLYCOL DIACRYLATE REINFORCED WITH PINEAPPLE FIBERS
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CALERO ALMEYDA CHRISTIAN 1, CABANZO HERNÁNDEZ RAFAEL 2, PERTUZ COMAS ALBERTO DAVID 3, MEJÍA OSPINO ENRIQUE 4, ESTUPIÑAN DURAN HUGO ARMANDO 5, V-NIÑO ELY DANNIER 6,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad Nacional de Colombia, 6 Fundación of Researchers in Science and Technology of Materials,
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Email: deydannv@gmail.com
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Abstract: The purpose of this research work is to evaluate the performance of a composite material, additively manufactured by means of the laser stereolithography technique, of a polymeric matrix of tripropylene glycol diacrylate reinforced with natural pineapple fibers at different concentrations. In this aspect, from the analysis of the mechanical and thermal properties obtained in tensile tests and mechanical dynamic analysis, a significant change in the reinforced material in comparison with the unreinforced material is evidenced.
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Topic: AM - Additive Manufacturing
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DESIGN AND FABRICATION METHODOLOGY FOR CANINE TRANSMETATARSAL PROSTHESES BY ADDITIVE MANUFACTURING.
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BAQUERO ARDILA MARÍA JULIANA 1, MANTILLA VILLALOBOS JAIRO ANDRÉS 2, VILLEGAS BERMUDEZ DIEGO FERNANDO 3, CASTELLANOS PARADA CAMILO ALEJANDRO 4,
1 Universidad Industrial de Santander, 2 Universidad industrial de Santander, 3 Universidad industrial de Santander, 4 Universidad Industrial de Santander,
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Email: camilokp27@gmail.com
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Abstract: A huge disadvantage in the daily life of any domestic animal is a limb absence, either by congenital or acquired disease, this situation prevents them from performing their usual activities properly and affects their owners emotionally. The importance of early post-trauma correction of this condition lies in the fact that various permanent musculoskeletal malformations may eventually occur as a result of improper posture and movement. Furthermore, the anatomical complexity of each case requires customized fabrication of a prosthesis, making the process costly and time-consuming. A proper solution for these requirements is provided by additive manufacturing, so in this paper we propose a design and fabrication methodology for low-cost customized prostheses applied to a case study, using computational modeling techniques and 3D printing as the main manufacturing method. We worked on the development of two transmetatarsal prostheses for a twelve-month-old female German Shepherd with absence of both hind limbs, to fulfill the function of the absent joints at tarsus level and accelerate the adaptation through the early device implementation. An initial amputated limb residual digitization was performed by photogrammetry to obtain the approximate geometry of each limb. Simultaneously, the biometry of the animal was taken in an anatomical position to make a comparison with the same breed canine in adult stage, in order to define the prosthesis dimensions and proceed with its design and modeling in a CAD software. Subsequently, the prostheses were manufactured by fused deposition modeling of flexible PLA+ with a focus on the variation of the filler density, with the purpose of modifying the mechanical properties in different sections of the impression, looking for rigidity in the support area and flexibility in the coupling with the residual limb. With the final implementation of the prostheses, a good fit was observed in the coupling with the limb, as well as a correct rigidity in the support validated by a stress-strain analysis by finite elements, which, combined with the structural design, has an impact on the proper posture and correct walking of the animal, concluding with a process of easy replicability and low cost that allows to obtain a quick solution for animals in a similar situation.
Keywords: Additive manufacturing, Animal prosthetics, Photogrammetry, Canine disability, Gait analysis.
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Topic: AM - Additive Manufacturing
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FATIGUE BEHAVIOR PREDICTION OF ADDITIVE MANUFACTURING COMPOSITES REINFORCED WITH LONG FIBERS USING MACHINE LEARNING
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SÁNCHEZ RESTREPO HERNÁN DAVID 1, HERNÁNDEZ SALAZAR CRISTIAN ANDRÉS 2, GONZÁLEZ-ESTRADA OCTAVIO ANDRÉS 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: agonzale@uis.edu.co
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Abstract: Additive manufacturing is a versatile manufacturing process that is quite useful for complex parts for which traditional methods would be difficult or outright impossible to fabricate. However, the technique has limitations associated with the low strength and stiffness characteristics of thermoplastic materials. For this reason, techniques such as Fused Deposition Modeling (FDM) have been discarded during the design process when functional load-bearing components are desired. In this research, experimental data from mechanical tests, tensile strength, and fatigue are analyzed to characterize the mechanical properties of Continuous Fiber Reinforced Thermoplastic Composites (CFRTPC). Nylon is used for the matrix filler, with triangular or hexagonal patterns. For reinforcement, fiberglass, carbon fiber, and Kevlar are used, using concentric rings and reinforcement layers with fiber in different orientations. The data processing was done through Machine Learning (ML), and regressions were obtained to characterize the behavior of the different compositions under the test stresses. The results showed that machine learning models were able to accurately predict the fatigue behavior of the composites with reasonable accuracy. Moreover, these models have the potential to be used for designing and optimizing composites produced by additive manufacturing processes.
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Topic: AM - Additive Manufacturing
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LSTM NETWORKS TO PREDICT MECHANICAL BEHAVIOR OF ADDITIVE MANUFACTURING COMPOSITES REINFORCED WITH CARBON FIBER
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GONZÁLEZ-ESTRADA OCTAVIO ANDRÉS 1, HERNÁNDEZ SALAZAR CRISTIAN ANDRÉS 2, LIZARAZO SANCHEZ EDINSON 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: edinson2228342@correo.uis.edu.co
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Abstract: Continuous fiber-reinforced additive manufacturing (cFRAM) composites have shown potential to improve the mechanical properties of 3D-printed polymers, but predicting their performance is a complex task due to their microstructure and various process parameters involved in their fabrication. Therefore, a long-short-term memory (LSTM) neural network is investigated to predict the mechanical properties, stiffness constants, and strength of cFRAM. In this study, the results of experimental tensile tests on continuous carbon fiber AM composites with variable volume fraction, printing direction, and fiber angle were used to train an LSTM neural network. The predictive model was compared to a micromechanical model of stiffness and strength to assess the accuracy, ease of implementation, and generalization capabilities of the machine learning algorithm. The results suggest that the prediction of the mechanical properties of cFRAM can be performed with reasonable accuracy.
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Topic: AM - Additive Manufacturing
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SAMPLE HOLDER FOR X-RAY DIFFRACTION: BRUKER D8 ADVANCE ECO DIFRACTOMETER
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ISAZA ZAPATA VIANCY CATHERINE 1, GRIMALDO MENDEZ PABLO 2, BETANCUR CHAVERRA DANIEL 3,
1 Institución Universitaria Pascual Bravo, 2 Institución Universitaria Pascual Bravo, 3 Institución Universitaria Pascual Bravo,
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Email: daniel.betancur137@pascualbravo.edu.co
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Abstract: Through this research, we sought to select and design a version of the already existing sample holders for the Bruker D8 Advance Eco diffractometer belonging to the Pascual Bravo University Institution, which is used to determine structural characteristics of materials. This process seeks, among other things, to reduce the cost of the sample holders since currently the costs associated with the sample holders are high and with designs that greatly limit the possibilities of measuring various samples. Due to the above, a design process was carried out seeking to meet the evidenced needs that the institution has had when analyzing the samples. Therefore, the selection of the most appropriate material was made considering conditions such as: weight, type of samples to be analyzed, behavior before radiation, ease of manufacture and cost. According to the above, the following materials for manufacturing were determined, these had to present an adequate behavior to the exposure of x-rays (radiotransparent and radiolucent) so that at the time of carrying out the tests the sample holder did not interfere with the reading of the material at To analyze, two materials that had this characteristic were chosen, which were PLA and AISI 304 stainless steel. After this, a removable sample holder design was proposed in CAD that allowed us to investigate conditions for the evaluation of the phase as a modification. of the height, the amount of volume, measurement surface, among others. Therefore, with this sample holder it was possible to modify the main geometry of the sample holder base considering the above and depending on whether the sample to be studied was solid (block) or powder. Once the final design was established, it was decided to manufacture the PLA sample holder through additive manufacturing of 3D printing. Diffraction tests for Silicon Oxide (SiO2) and Aluminum Oxide (AlO2) were carried out and the phases were analyzed, verifying the quality of the results. After this, it was possible to show that the results of the diffraction patterns of both Oxides corresponded to those that should be obtained, which was an important result, considering that the sample holder made with PLA has an approximate cost of 1,500 times less than those offered by the manufacturer.
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Topic: BC - Biomedical Coatings
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PRODUCTION AND CHARATERIZATION OF RHENIUM-CARBON BASED COATINGS DEPOSITED BY SPUTTERING TECHNIQUE
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OROZCO HERNANDEZ GIOVANY 1, APERADOR CHAPARRO WILLIAN ARNULFO 2, PINEDA TRIANA YANETH 3, RAMÍREZ MONROY JULIANA VALERIA 4, CORREDOR FIGUEROA ADRIANA PATRICIA 5, VERA LÓPEZ ENRIQUE 6, LEMUS RINCÓN MELANY LISBETH 7,
1 Universidad ECCI, 2 Universidad Militar Nueva Granada, 3 Universidad Pedagógica y Tecnológica de Colombia, 4 Universidad Pedagógica y Tecnológica de Colombia, 5 Universidad ECCI, 6 Universidad Pedagógica y Tecnológica de Colombia, 7 Universidad ECCI,
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Email: melanyl.lemusr@ecci.edu.co
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Abstract: One of the most widely used techniques for producing highly homogeneous thin film coatings is physical vapor deposition (PVD). These coatings have been shown to increase mechanical, physical, and chemical properties, depending on the elements or alloys that are deposited, thus providing better capabilities for various applications. The magnetron-assisted sputtering technique has been extensively studied using targets of different elements and/or compounds. In this case, Rhenium was studied as the element to coat pure titanium substrates, along with the use of Carbon to achieve rhenium carbides like compounds which could improve the chemical and biocompatibility properties of the titanium substrate. A molybdenum target was also used as an anchoring layer to improve the adhesion of the upper layer.
The deposition process parameters of this coating were the substrate temperature, target power, gas flow rate, substrate rotation, and target-to-substrate distance. In order to find the parameters that generated greater adhesion and uniformity in the deposition, a systematic study was conducted on the influence of these parameters on the coatings. The characterization of these layers was performed by scanning electron microscopy (SEM) which showed that the visual adhesion of the coatings improved with increasing substrate temperature, energy dispersive spectroscopy (EDS) showing the elemental species present on the surface confirming its homogeneity, and X-ray diffraction (XRD) which showed signals of crystalline phases of compounds based on rhenium and carbon. Based on the best deposition process conditions, in vitro biocompatibility tests are being performed using Trypan blue and MTT tests.
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Topic: CM - Characterization of Materials
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AFFECTATION IN FATIGUE RESISTANCE IN STAINLESS STEELS WITH WELDED JOINTS
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BOHORQUEZ BECERRA OSCAR RODOLFO 1, PERTUZ COMAS ALBERTO DAVID 2, GONZALEZ RODRIGUEZ JHON FREDY 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander ,
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Email: jhonfredygonzalezrodriguez@gmail.com
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Abstract: Steel is very useful for many sectors nowadays, it is characterized as being hard and resistant, besides having great malleability. This material is in great demand in industries such as automotive, power generation, pharmaceutical, and food. They also make use of stainless steel, which has similar characteristics to those mentioned above with the addition that they are resistant to corrosion, in addition, they can be austenitic, martensitic, or ferritic. On the other hand, being such a demanded material, it is necessary to optimize the processes of transport, cutting, welding, and material saving, in order to generate advances in the metal-mechanical industry. Welding is a process that is carefully analyzed, the most appropriate method must be chosen for the material, looking for the best mechanical properties in critical test conditions. Therefore, to achieve these standards, the material was experimented with in controlled environments under international standards, the analysis was performed on 316L stainless steel with a welded joint, by the GMAW welding process, the main objective was to analyze the welded joint, and the changes that may occur with respect to the control material, which in this case was the initial material without the welded joint, the material was taken to critical loading conditions, with tensile tests that allowed to continue with the research delivering values of elastic limit. In this way, fatigue was performed at 4 stress levels associated with the yield stress for the analysis based on Basquin's model, it was observed how the structure changed when it was taken to the limit with this type of destructive test. In obtaining the specimens, the welding parameters for the working conditions initially proposed were sought, following the indications of the material manufacturer, a material metallurgically similar to the base plate was used as welding material. The GMAW welding process was carried out under the standards of the AWS D1.1 norm, with an automatic electromechanical system with constant displacement, on a horizontal surface, for the cutting of the specimens was guaranteed not to thermally affect the samples. Micrographs were taken with an optical microscope, for this process, it was required a treatment of samples in which they were roughened by hand with abrasive paper, then the material was attacked with reagent according to ASTM E407 standard, for proper visualization of the microstructural changes. Therefore, from the study of the micrographs results were obtained, comparing the formation of microstructures predicted by the Schaeffler diagram with the analysis performed on the images of the material. The analysis of the welded joint showed a notable difference with respect to the control material with each of the studies performed, but in the microstructures, changes in the material were noted that affected the corrosion resistance properties of the material used for this work. On the other hand, it was compared and a relationship was established between the equations obtained by the fatigue analysis model, with this relationship it can be set numerically how much the change between the welded material and the control material with the fatigue test.
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Topic: CM - Characterization of Materials
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A FIRST PRINCIPLES STUDY OF THE CO2 CAPTURE BY SMALL COPPER CLUSTERS
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MENA CORONADO CAMILA ANDREA 1, ALCALÁ VARILLA LUIS ARTURO 2, TORRES HOYOS FRANCISCO JOSÉ 3,
1 Universidad de Córdoba - Colombia, 2 Universidad de Córdoba - Colombia, 3 Universidad de Córdoba - Colombia,
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Email: ftorres@correo.unicordoba.edu.co
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Abstract: The CO2 adsorption on small copper clusters (CuN, N=2-5 atoms) was studied using density functional theory (DFT) under the GGA approximation of Perdew-Burke-Ernzerhof (PBE), the Hubbard U correction and considering the Van der Waals interactions. We found that chemisorption is not possible when the copper cluster only has two atoms, while for systems with three or more atoms, CO2 can be chemisorbed. We report here the CO2/CuN structures that present chemisorption and for them we also calculated the structural and electronics properties and the phonon density of state. We can conclude that the adsorption of CO2 on the small copper clusters could favor the dissociation of CO2.
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Topic: CM - Characterization of Materials
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ANALYSIS OF STATIC AND FATIGUE PROPERTIES OF BIO-BASED EPOXY COMPOSITES REINFORCED WITH WOVEN FIQUE, JUTE, AND FLAX FIBERS
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CASTRO BERMUDEZ JUAN DAYAL 1, PERTUZ COMAS ALBERTO DAVID 2,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander,
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Email: apertuzc@uis.edu.co
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Abstract: In recent decades, bio-composites have emerged as a sustainable alternative to traditional low-stress designs. The use of natural fibers as construction materials has gained popularity due to its low cost, environmental friendliness, and agro-industrial benefits. Among these fibers, Fique, Jute, and Flax have been commonly used as reinforcing materials in combination with epoxy resin matrix, resulting in improved maximum stress values in composite materials. Moreover, the investigation of the dynamic properties of biocomposites has become an innovative research field. The use of classic methodologies such as the Basquin model has enabled the definition of the S-N curve to predict high-cycle behavior with reduced experimental tests.
This research aims to analyze the static and dynamic behavior of a bio-based resin reinforced with woven fibers of Jute, Fique, and Flax. The study evaluates the Young Modulus, Ultimate Strength, and Strain of the three composites, with Fique and Flax fibers yielding the best results. Furthermore, fatigue tests were performed on Fique and Flax composites, and an S-N curve was obtained to predict the high-cycle behavior of the materials.
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Topic: CM - Characterization of Materials
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CHARACTERIZATION OF A PUMICE STONE GEOPOLYMER AND ITS SELECTIVITY IN THE REMOVAL OF IONIC CONTAMINANTS
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BARÓN GUALDRÓN GISELLE CAROLINA 1, MONTAÑO ANGARITA ANGELA MARCELA 2, GONZALEZ CUERVO CLAUDIA PAULINA 3, JEREZ SANTAMARIA DANIELA ALEXANDRA 4, URBINA JUAN MANUEL 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Pontifica Bolivariana, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Santander,
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Email: giselle.baron@correo.uis.edu.co
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Abstract: Geopolymers are inorganic materials that are the product of the reaction of aluminosilicates in the presence of an alkaline activator, which promotes the dissolution of the precursor, allowing the formation of monomers that subsequently form a three-dimensional red. The various uses in which they can be implemented extend to the range of materials with adsorbent characteristics, which have been studied in recent years, with selectivity being one of the most important characteristics when performing removal in real systems, since that from it appeared, the efficiency of water decontamination for specific contaminants. The present work proposes the selectivity of a pumice-based geopolymeric material to remove ionic contaminants in wastewater, finding that the synthesized geopolymer removes up to 38% methylene blue, 25% methyl orange and 20% methyl violet in 90 min, which is indicative that the geopolymeric material has a tendency to retain the methylene blue dye in a higher proportion, this may be due to the volume of the molecule and the fact that its residual charge stabilizes the structure of the material polymeric, itself through the characterization techniques the morphological and structural change of the raw material is evidenced, which indicates that the polymerization process is carried out successfully and through the BET methodology we can observe that the average size of the pores in the material is 19 nm and can be classified as a mesoporous material
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Topic: CM - Characterization of Materials
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CHARACTERIZATION OF INDUSTRIAL WASTE OF FT5 (FOUNDRY TITANIUM GRADE 5) FOR APPLICATION IN PARTS OF THE AUTOMOTIVE INDUSTRY
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ISAZA ZAPATA VIANCY CATHERINE 1, ARANGO AGUIAR DANIELA 2, PEREZ MEJIA FERNANDO 3, CALLEJAS DANIEL 4,
1 Institución Universitaria Pascual Bravo, 2 Institución Universitaria Pascual Bravo, 3 Institución Universitaria Pascual Bravo, 4 Institución Universitaria Pascual Bravo,
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Email: d.callejas1832@pascualbravo.edu.co
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Abstract: Through this investigation, suitable conditions were found for the recovery of pure titanium (ASTM F67-06) and grade 5 alloyed titanium (ASTM F136-08) residues, both surgical alloys and from die-cutting and machining processes. the company Industrias Medicas San Pedro. The main function of these pieces is to replace bone parts such as the face, skull, and maxillofacial section. The residual material was cataloged to be used in the construction of titanium parts for the automotive industry. For this, a chemical-mechanical (metallographic) polishing process was carried out, which allowed the revelation of the alpha phase of pure titanium and grade 5 titanium in the hard Widmanstätten phase. It is concluded that, although the material suffered deformations due to mechanical processes, this at the microstructural phase level remained stable and did not generate compositional changes in the material to be used. Once the composition remained stable, the use of the vacuum casting technique was theoretically proposed to obtain a chemically stoichiometric and uniform casting for the reproduction of parts.
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Topic: CM - Characterization of Materials
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CHARACTERIZATION OF NICKEL COBALTITE NANOPARTICLES OBTAINED BY SOL-GEL TECHNIQUE: OPTICAL AND STRUCTURAL STUDY
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RINCÓN JOYA MIRYAM 1, CARDENAS FLECHAS LEYDI JULIETA 2,
1 Universidad Nacional de Colombia, 2 Fundación Universidad de América ,
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Email: leydi.cardenas@profesores.uamerica.edu.co
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Abstract: This study examines the characteristics of cobalt oxide and nickel cobaltite prepared via the citrate sol-gel technique at 1000°C. The goal is to optimize the deposition process for gas sensors that can detect acetone, a diabetes biomarker, by exploring the effect of different nickel percentages in the compound. XRD, FT-IR, SEM, and UV-Vis techniques were employed to characterize the samples. The results indicate the presence of NiCo2O4 and CoO, shifts in the characteristic peaks of nickel cobaltite due to doping, and variations in particle size and band gap values depending on the nickel concentration. In summary, the study shows that doping can significantly influence material properties, with potential implications for gas sensor design and development in biomedical applications.
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Topic: CM - Characterization of Materials
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CHARACTERIZATION OF STRUCTURAL AND ELECTRONIC PROPERTIES OF ZINC OXIDE WITH CERIUM IMPURITIES
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DORIA HERNÁNDEZ ÁNGELES DEL CARMEN 1, ORTIZ ROMERO JOSÉ DANIEL 2, ALCALÁ VARILLA LUIS ARTURO 3,
1 Universidad de Córdoba, 2 Universidad de Córdoba, 3 Universidad de Córdoba - Colombia,
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Email: lalcala@correo.unicordoba.edu.co
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Abstract: In this work we have investigated the effects of Cerium impurities on the structural and electronic properties of Zinc Oxide in its Wurtzite phase, for the Bulk and Surface (001) of pure ZnO and the Zn_x Ce_(1-x) O doped system, this to determine the possible improvements in the photocatalytic activity that Ce produces in the ZnO system. the calculations were made using the density functional theory (DFT) within the generalized gradient approximation (GGA) of Perdew-Burke-Ernzerhof (PBE), together with ultrasmooth atomic pseudopotentials and a plane wave base as implemented in the Quantum-ESPRESSO package. The doping concentration levels considered in this work were 12.5% for the Bulk, and 6.25% for the Surface. It was found that when adding Ce impurities to ZnO, the structural parameters slightly changed, changes were also presented in the electronic properties of the material, appearing intermediate states in the forbidden energy band, located around the Fermi energy. This may suggest that probably the Zn_0,875 Ce_0,125 O and Zn_0,9375 Ce_0,0625 O systems can absorb visible light, which could lead to possible improvements in the photocatalytic properties of the material.
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Topic: CM - Characterization of Materials
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CHARACTERIZATION OF THE PLANT SPECIES OPUNTIA FICUS INDICA CULTIVATED IN BOYACÁ - COLOMBIA AS POTENTIAL CORROSION INHIBITOR.
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LARA CUSBA MICHAEL GEOVANY 1, HERNÁNDEZ CARRILLO CARLOS GABRIEL 2, PINEDA TRIANA YANETH 3, TORRES GÓMEZ ROBINSON DE JESÚS 4, MUJICA RONCERY LAIS 5,
1 Universidad Pedagógica y Tecnológica de Colombia , 2 Universidad Pedagógica y Tecnológica de Colombia , 3 Universidad Pedagógica y Tecnológica de Colombia, 4 Universidad Pedagógica y Tecnológica de Colombia , 5 Universidad Pedagógica y Tecnológica de Colombia,
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Email: lais.mujica@uprc.edu.co
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Abstract: Corrosion inhibitors have generated a remarkable effectiveness in the protection of the corrosive reaction to the different environmental conditions of steels, especially those destined to engineering functions. Likewise, it is necessary the production of raw materials corresponding to the search for environmental sustainability. Specifically, cacti plant species. However, despite its wild growth throughout the Colombian territory, it is little used and its physicochemical behavior is not clear. Therefore, this research proposes the development of a corrosion inhibitor extracted from the plant species Opuntia ficus indica grown in Boyacá, in order to establish its use as a potential corrosion inhibitor, by understanding the chemical phenomena present. For this purpose, the species was initially characterized botanically to control the components and later a bromatological analysis was performed to define compounds that establish potential physicochemical phenomena and then Thermogravimetric Analysis was carried out. Initially, the results show that approximately 95% of the plant is composed of water, which is related to the high potential for electrostatic interaction. This was evaluated by infrared and Raman spectroscopy analysis, which allowed the semiquantitative evaluation of the presence of hydroxyl and carboxyl functional groups that compose polysaccharide chains, which corresponds to approximately 85% of the total composition according to the bromatological analysis. This is related to the results of the zeta potential and the generation of a large interface that allows reducing the electrochemical reactions causing corrosive effects.
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Topic: CM - Characterization of Materials
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CHARACTERIZATIONS OF PB(ZR0,52TI0,48)O3/COFE2O4 MULTIFERROIC PARTICULATES COMPOSITES IN 80/20 AND 50/50 MOLAR PROPORTIONAL BY MICROWAVE-ASSISTED METHOD
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PARRA-JIMENEZ KORLLVARY 1, GARCÍA-NEGRETE CARLOS 2, FERNANDEZ PERDOMO CLAUDIA PATRICIA 3, KIMINAMI RUTH H. G. A. 4, GARCIA DUCINEI 5, DE OLIVEIRA ADILSON JESÚS APARECIDO 6,
1 UNIVERSIDAD DEL SINU - ELIAS BECHARA ZAINUM, 2 Universidad del Sinú ? Elias Bechara Zainúm, 3 Universidade Federal de São Carlos, 4 Universidade Federal de São Carlos , 5 Universidade Federal de São Carlos, 6 Universidade Federal de São Carlos,
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Email: adilson@df.ufscar.br
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Abstract: In this work, we present a studied of the electric and magnetic properties in Pb(Zr0,52Ti0,48)O3/CoFe2O4 (PZT/CFO) of the multiferroic particulate composite; the samples were synthesized Pechini method with two different concentration (80/20 and 50/50). After synthesis the samples were pressed and sintered in an ultrafast microwave-assisted sintering (MS) and in a conventional furnace (CS). The structure and microstructure of the sintered samples were analyzed, respectively, by X-ray diffraction and scanning electron microscopy. The dielectric constant as a function of temperature, electrical resistivity, ferroelectric hysteresis, magnetic hysteresis, magnetostriction effect, and magnetoelectric coupling coefficient were measured. The micrographs indicated that sintering resulted in globally connected particle composites (0-3) and a uniform distribution of the ferromagnetic phase grains (CFO) in the ferroelectric matrix (PZT). The characterizations revealed high values of resistivity indicated that both sintering methods preserved the integrity of the two phases. The dielectric constant of the samples increased with increasing temperature and peaked at a particular temperature, temperature Curie, which is characteristics of ferroelectric behavior. The results revealed that for the two fractions of cobalt ferrite in the composite (80/20 and 50/50), the dielectric constant and transition temperature decreased by MS. The electric polarization saturation (ferroelectric hysteresis) for MS was lower than CS. The saturation magnetization (magnetic hysteresis) for MS was higher than CS. The magnetostriction coefficients as a function magnetic field for MS was lower than CS, and the magnetoelectric susceptibility for MS was higher than CS, the values were dependent on the ferrite phase concentration and sintering. The microwave sintering was more efficient, ensuring the magnetoelectric behavior of all the composites under study.
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Topic: CM - Characterization of Materials
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CHITOSAN-ACTIVATED CARBONS: AN OPTION FOR THE MANUFACTURE OF LOW-COST SUPERCAPACITOR ELECTRODES
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FERRER PACHECO MARTHA YASMID 1, VERA EDGAR JOEL 2, DULCE MORENO HECTOR JAIME 3,
1 Universidad Francisco de Paula Santander, 2 Universidad Francisco de Paula Santander, 3 Universidad Francisco de Paula Santander,
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Email: hectorjaimedm@ufps.edu.co
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Abstract: ctivated carbon (AC) is obtained from commercial chitosan by the hydrothermal carbonisation method, assisted with phosphoric acid and subsequent physical activation at temperatures of 500, 700 and 900 ?C. The coals obtained were physically and chemically characterised using techniques such as: TGA,?FTIR, and SEM/EDS. Surface area and pore size were determined from N2 sorption and desorption analysis. The electrochemical properties were evaluated by voltammetric tests in a three-electrode cell with a 1M HCl electrolyte, for which AC working electrodes and copper tape were fabricated.
Coals with a pore size of less than 2 nm were obtained, indicating that they are microporous coals. The highest surface area was presented by the CA at 900?C, 627.423 m2⁄g, which also had the highest specific capacitance of 346 μF/g.
The hydrothermal carbonisation method combined with physical activation was found to be efficient to produce CAs from chitosan, with large surface areas, of great importance for the fabrication of supercapacitor electrodes.
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Topic: CM - Characterization of Materials
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CONSEQUENCES OF ADDING SMALL COPPER CLUSTERS ON THE 001 SURFACES OF ANATASE
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ALCALÁ VARILLA LUIS ARTURO 1, TORRES HOYOS FRANCISCO JOSÉ 2, DE LA ESPRIELLA VÉLEZ NICOLÁS 3,
1 Universidad de Córdoba - Colombia, 2 Universidad de Córdoba - Colombia, 3 UNIVERSIDAD DE CÓRDOBA,
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Email: ndelaespriella@correo.unicordoba.edu.co
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Abstract: Using first-principles simulations based on the density functional theory (DFT) under the GGA approximation of Perdew-Burke-Ernzerhof (PBE), the Hubbard U correction and considering the Van der Waals interactions, we have investigated the effects that produce to add small copper clusters (CuN, N=1-4 atoms) on the 001 surfaces of anatase. It has been found that the main effects of copper clusters on the electronic properties of anatase are to produce midgap states of two different way. The frist are Cu−Ti bonds and the second one are Ti3+ polarons states. Here, we discuss how these states could improve the photocatalytic activity of anatase.
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Topic: CM - Characterization of Materials
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CURRENT EFFECT ON THE CRITICAL PARAMETERS FROM PARACONDUCTIVITY ANALYSIS FOR THE HIGH-TEMPERATURE SUPERCONDUCTOR GDBA2CU3O7-δ
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ROA-ROJAS JAIRO 1, VARGAS-PINEDA ELIANA MARCELA 2, RIVERA CONTRERAS LEYDA JULIANA 3, LANDINEZ TELLEZ? ?DAVID ARSENIO 4,
1 Universidad Nacional de Colombia - Bogotá, 2 Universidad Nacional de Colombia, 3 Universidad Nacional de Colombia, 4 Universidad Nacional de Colombia,
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Email: dalandinezt@unal.edu.co
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Abstract: Using the solid-state reaction, the high temperature superconducting material GdBa2Cu3O7-δ was synthesized and his resistive behavior was studied as a function of temperature under the application of seven different electric currents to report the results obtained from the analysis of the paraconductivity (excess of conductivity) fluctuations in the phase transition from the normal state to the superconducting state of a ceramic sample.
Through the resistive behavior of the sample in the pairing, the critical superconducting parameters characterizing the of ceramic GdBa2Cu3O7-δ were determined: penetration length, coherence length, critical magnetic fields one and two, critical current density, jump in specific heat at the superconducting transition and Ginzburg parameter which are not affected by the variation in the applied current.
This talk will show the method used to perform the experimental characterization of a high critical temperature superconducting material and will review the most relevant aspects of the Ginzburg and Landau theory.
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Topic: CM - Characterization of Materials
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DETERMINATION OF THE STRUCTURAL BEHAVIOR OF FIBER-REINFORCED MICROCONCRETE PLATES FOR LOAD-BEARING WALL SYSTEMS
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PALACIOS PABON JOSE DANIEL 1, SANCHEZ MOLINA JORGE 2,
1 UNIVERSIDAD FRANCISCO DE PAULA SANTANDER, 2 UNIVERSIDAD FRANCISCO DE PAULA SANTANDER,
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Email: jorgesm@ufps.edu.co
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Abstract: Concrete is a compound of cement, water, aggregates and additives that has excellent physical and mechanical properties. According to its composition, concrete can be classified as microconcrete when it is only made up of aggregates with particles smaller than 2.5 millimeters. On the other hand, natural fibers are reinforcing materials that have been used since ancient times, such as the use of horsehair and straw to reinforce mud bricks. When microconcrete is combined with fiber-reinforcement, a material with its own qualities is obtained for use in elements subjected to flexion and compression. The aim of this work is to determine the structural behavior of fiber-reinforced microconcrete plates with natural fibers of vegetable origin for load-bearing wall systems. Fibro-reinforced microconcrete mixes were developed, where different types of natural fibers were used, which underwent chemical treatment with sodium hydroxide and calcium hydroxide to remove lignin and thus reduce the alkaline reaction between the cement and the fibers, increasing the durability of the compound. Four microconcrete mixtures were made with fibers from fique, guadua, the stem of the banana palm and sugarcane bagasse. The results were compared with simple microconcrete and fibro-reinforced with fiberglass, the latter being the one that has presented the best properties in comparison with other types of artificial fibers. In conclusion, it was obtained that the mixtures reinforced with fique fibers present similar results to the mixture with fiberglass, while the samples with fibers of guadua, stem of the banana palm and sugarcane bagasse do not present a significant contribution. to structural behavior. Therefore, for the construction of load-bearing walls, it was determined that the fiber-reinforced micro-concrete plates with fique fibers have an adequate structural behavior to flexo-compression, shear and, in addition, they present optimal rigidity for their use in the construction.
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Topic: CM - Characterization of Materials
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DEVELOPMENT OF A MEASUREMENT SYSTEM TO QUANTIFY ELECTRICAL RESISTIVITY IN SOLID MATERIALS
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PARRA VARGAS CARLOS ARTURO 1, MORENO PRECIADO DANIEL ARTURO 2, CUERVO FARFÁN JAVIER ALONSO 3, CUERVO ESTEBAN 4, JIMÉNEZ LÓPEZ FABIAN ROLANDO 5, SIERRA HERRERA OSCAR HUMBERTO 6,
1 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 2 Universidad Pedagógica y Tecnológica de Colombia, 3 Universidad Pedagógica y tecnológica de Colombia-Tunja, 4 DSP, Escuela de Ingeniería Electrónica, Facultad de Ingeniería, Universidad Pedagógica y Tecnológica de Colombia, 5 DSP, Escuela de Ingeniería Electrónica, Facultad de Ingeniería, Universidad Pedagógica y Tecnológica de Colombia, 6 DSP, Escuela de Ingeniería Electrónica, Facultad de Ingeniería, Universidad Pedagógica y Tecnológica de Colombia,
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Email: oscar.sierra@uptc.edu.co
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Abstract: Measurement of the electrical resistance of a material is very important when characterizing it, because some of its possible technological applications can be glimpsed. To carry out these measurements it is necessary to have some way to apply voltage and current to the material, in the same way it must be possible to measure the current and voltage that flows through it with a measurement range that includes nanometric magnitudes. For the measurement of resistivity in materials, there are mainly two methods, four and two point probe technique, each one with its respective advantages. Currently, it is possible to find equipment on the market that performs these tasks, however, its cost is too high and they do not have multiplexing between the two methods. Therefore, the design and operation of the prototype of a low-cost solid-state material resistivity measurement system is presented, with subsequent visualization through the design and implementation of a graphical interface.
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Topic: CM - Characterization of Materials
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DOSIMETRIC CHARACTERISTICS OF THE MAIN THERMOLUMINESCENT GLOW PEAK OF AQUAMARINE.
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VALDELAMAR MENA RAEDER 1, COGOLLO PITALUA RAFAEL RICARDO 2, HERRERA CUITIVA JORGE ISAAC 3, GUTIÉRREZ FLORES OMAR DARIO 4,
1 Universidad de Cordoba , 2 Universidad de Cordoba, 3 Universidad de Cordoba, 4 Universidad de Cordoba,
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Email: omardariogutierrez@gmail.com
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Abstract: The dosimetric response of the main thermoluminescent glow peak of aquamarine, cyan variety of beryl (Be3Al2(SiO3)6), is reported. Samples were irradiated at room temperature using a 90Sr/90Y β source at a dose rate of 0.10 Gys-1. Measurements made at a heating rate of 1°C/s after irradiation of 1 to 100 Gy of β radiation show a main peak at 75°C followed by three secondary peaks at 113, 188 and 306°C respectively.
The main peak dose response is linear within the first 10 Gy, but tends to sublinearity as the dose extends up to 100 Gy of β radiation. The peak fades with the delay between irradiation and measurement to about 14% of its initial value 600 s after irradiation. Reproducibility analysis shows that the material reproduces its response under identical experimental conditions with an uncertainty of 0.8% after a beta dose irradiation of 10 Gy.
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Topic: CM - Characterization of Materials
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EFFECT OF ARGON PLASMA TREATMENT ON THE PROPERTIES OF BIOCOMPOSITES MADE WITH RATAN AND BAMBOO FIBERS
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SÁNCHEZ CRUZ MARTHA LISSETTE 1, MORALES LUZ YOLANDA 2, CAPOTE RODRÍGUEZ GIL 3,
1 Universidad Militar Nueva Granada, 2 Universidad Militar Nueva Granada, 3 Universidad Nacional de Colombia,
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Email: gcapoter@unal.edu.co
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Abstract: The use of plant fibers as reinforcement for polymeric composites requires the application of surface modification treatments. These treatments improve the adhesion of the fibers to the polymer, increase the material's strength, and reduce its absorption capacity. In this study, the effect of cold argon plasma treatment on the properties of biocomposites made from Rattan and Bambusa Vulgaris fibers and a vegetable-based polyurethane from castor oil was analyzed. The compression molding method was used to manufacture the panels, applying constant pressure and controlled temperature to bond the constituent materials of the composite. To improve the mechanical strength and uniform distribution of loads in the panel, fibers of 30 cm in length were used, oriented along two orthogonal axes, forming [0/90]s weaves. The results obtained show that by applying cold argon plasma treatment, the tensile strength, flexural strength, and toughness of the composite can be improved. Additionally, plasma treatment can enhance moisture resistance, which can expand its range of applications and improve its lifespan in humid environments.
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Topic: CM - Characterization of Materials
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ELABORATION AND CHARACTERIZATION OF BIOPLASTICS FROM MIXTURES OF STARCH OBTAINED FROM AVOCADO SEEDS AND SILVER NANOPARTICLES
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CARREÑO FLOREZ EDGAR FARID 1, MEZA-BARBOSA CARLOS ALBERTO 2, PEÑA RODRIGUEZ GABRIEL 3,
1 Universidad Francisco de Paula Santander, 2 UFPS, 3 UFPS,
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Email: gabrielpr@ufps.edu.co
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Abstract: The purpose of this research is to obtain and characterize morphological, structural, chemical, thermal and mechanical bioplastics from hass avocado (Persea americana 'hass) seed starch in a matrix loaded with silver nanoparticles (AgNP's). The starches were extracted by the wet alkali method with sodium hydroxide-NaOH at 0,2% w/w and treatment with sodium metabisulfite-Na2S2O5 at 0,2% w/w and subsequent structural, morphological and physicochemical characterization. The silver nanoparticles were synthesized by electrochemical methods and characterized morphologically and chemically by Transmission Microscopy (TEM), and Microanalysis by Energy Disperse X-ray Spectroscopy (EDS). The extracted starch was used as an active polymeric source in amounts of variable formulation, carrying out previous tests to identify the mixing proportions in the formation of the semicrystalline solid, with water, acetic acid, glycerin, and silver particles mixing through the technique casting in plasticizer concentrations of 10 to 30 g/100 g of starch at 80°C for 10 min. Subsequently, the masses obtained were subjected to the process of physical modification and pelleting with a humidity setting of approximately 50%. The average starch extracted from Hass avocado seeds was 2895,03g of dry powder at 35°C, which represents a yield of 14,93%. A type B structure is evidenced with a crystallinity of 38,63% showing thermal and granular coupling in the polymeric structure. Starch extraction was successful and its yield can be considered low, however, the environment and food safety can be benefited thanks to the intelligent transformation of this waste, which can be used in food and non-food systems.
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Topic: CM - Characterization of Materials
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EVALUATION OF THE ELECTRICAL AND MAGNETIC PROPERTIES OF THE BI1-XYBXFEO3 (0
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CASTAÑEDA MENDOZA MICHAEL STEVEN 1, SAAVEDRA GAONA INDRY MILENA 2, PARRA VARGAS CARLOS ARTURO 3, SUPELANO GARCÍA IVÁN 4, FONSECA BECERRA LAURA CRISTINA ISABEL 5, SUAREZ VERA SHARON GERALDINE 6,
1 Universidad Pedagógica y Tecnológica de Colombia, 2 Grupo Física de Materiales, 3 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 4 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 5 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 6 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia,
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Email: sharon.suarez@uptc.edu.co
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Abstract: The BiFe1-xYbxO3 (x=0.00, 0.02, 0.04, 0.05, 0.06 and 0.10) system was produced by the standard solid-state reaction method. The structural properties at room temperature were studied by Rietveld analysis of X-ray diffraction patterns, these reveal that samples crystallizes in majoritarian BiFe1-xYbxO3 phase with trigonal R 3 m (#160) space group. Magnetic measurements as a function of temperature performed on vibrating magnetometer signals two magnetic behaviors, first one for x<0.05 and a second one for x>0.06. The resistivity measurements as a function of temperature exhibits insulating behavior. Polarization curves were collected at room temperature displaying a ferroelectric signature.
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Topic: CM - Characterization of Materials
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EVALUATION OF THE STRUCTURAL, MORPHOLOGICAL AND OPTICAL PROPERTIES OF THE CUO/WO3 SYSTEM
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CASTAÑEDA MENDOZA MICHAEL STEVEN 1, RABA PÁEZ ANGELA MERCEDES 2, RINCÓN JOYA MIRYAM 3, MURILLO RUÍZ EDWIN ALBERTO 4, PARRA VARGAS CARLOS ARTURO 5,
1 Universidad Pedagógica y Tecnológica de Colombia, 2 Universidad Francisco de Paula Santander, 3 Universidad Nacional de Colombia, 4 Universidad Francisco de Paula Santander, 5 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia,
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Email: carlos.parra@uptc.edu.co
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Abstract: CuO has been used as a p-type counterpart to WO3 (n-type) in various applications, such that the CuO/WO3 system has shown better performance than individual CuO and WO3 in gas sensor response for the detection of volatile organic compounds. On the other hand, the coexistence of copper and tungsten oxides in a heterostructure can improve the catalytic reduction capacity of this system. Considering these precedents, the CuO/WO3 system was produced by a wet method, in order to establish the influence of synthesis parameters on its structural, morphological and optical properties. A first quantification of the crystalline phases present in the CuO/WO3 system was carried out using the X-ray diffraction (XRD) technique; 76% of CuO and 24% of WO3 were the initially established percentages. The study of the morphological properties was carried out with transmission electron microscopy (TEM). The optical characterization was carried out with the diffuse reflectance spectroscopy (DRS) technique. From these results, it was possible to establish the presence of two band gap energy values, 1.68 eV and 2.96 eV, values directly associated with the two oxides present in the system.
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Topic: CM - Characterization of Materials
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KINETIC ANALYSIS OF THE GLOW CURVE OF α-AL 2O3
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COGOLLO PITALUA RAFAEL RICARDO 1, CASTRILLON BARON MOISES DAVID 2, ESPITIA PAÉZ YULISSA CAROLINA 3, GUTIÉRREZ FLORES OMAR DARIO 4,
1 Universidad de Cordoba, 2 Universidad de Cordoba, 3 Universidad de Cordoba, 4 Universidad de Cordoba,
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Email: omardariogutierrez@gmail.com
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Abstract: In this work, the kinetic parameters of the main thermoluminescence (TL) peak of pure alumina (α-Al2O3) samples irradiated at different doses are reported. The TL behavior is analyzed as a function of dose. The pellets were irradiated at different X-ray doses using a 6 MeV linear accelerator (LINAC), in the air at room temperature, located at the Instituto Medico de Alta Tecnología (IMAT) in Monteria City. The TL reading of the samples was performed on a Bicron® TLD 4500 system. The Initial Rise (IR), Peak shape (PS), Whole glow peak (WGP), and Curve fitting (CF) methods were used to carry out a detailed kinetic analysis. Analysis of the TL shows that the alumina arrays contain more than one type of trap due to several points of maximum luminous emission intensity in the TL glow curve. The glow curves of the pure alumina samples exhibited a total of three glow peaks with the main peak located between 160 and 170°C. The kinetic parameters (activation energy E, frequency factor s, and order parameter b) of the main peak of the TL glow curve are independent of the radiation dose received by the material. Dosimetric properties such as dose response and reproducibility are also reported.
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Topic: CM - Characterization of Materials
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MESOPOROUS PRCOO3 DOPED SR (0.1
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MORENO ANDREA 1, AGUILAR CAROL 2,
1 Fundación Universitaria de Popayán, 2 Universidad Del Valle- Universidad del Cauca ,
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Email: carola@unicauca.edu.co
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Abstract: Mesoporous nanostructures of the Pr1-xSrxCoO3 system were synthesized via sol gel using Cetyltrimethylammonium bromide (CTAB), as surfactant, and two different solvents, ethanol and ethylene glycol. To determine the effect of the synthesis process on the characteristics of the nanostructures, these were characterized using FTIR and UV-Vis diffuse reflectance (DRS) spectroscopies, photoluminescence, X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms and transmission electron microscopy (TEM). The Pr1-xSrxCoO3 powders were found to have nanometric-sized monocrystalline primary particles (50-100 nm) and their adsorption-desorption isotherms showed the type H1 hysteresis loops characteristic of mesoporous solids, a nature confirmed by the TEM micrographs. The obtained mesoporous Pr1-xSrxCoO3 (0.1
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Topic: CM - Characterization of Materials
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OBSERVATION OF GRANULAR JOSEPHSON MECHANISM AND THE VORTEX-GLASS TRANSITION IN THE POLYCRYSTALLINE SUPERCONDUCTOR GDBA2CU3O7-D
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VARGAS-PINEDA ELIANA MARCELA 1, RIVERA CONTRERAS LEYDA JULIANA 2, ROA-ROJAS JAIRO 3, LANDINEZ TELLEZ? ?DAVID ARSENIO 4,
1 Universidad Nacional de Colombia, 2 Universidad Nacional de Colombia, 3 Universidad Nacional de Colombia - Bogotá, 4 Universidad Nacional de Colombia,
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Email: dalandinezt@unal.edu.co
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Abstract: The resistive transition between the normal and superconducting states in high critical temperature superconducting materials, is characterized by the occurrence of two well-defined stages: one transition called pairing transition and another one known as coherence transition. In the second one, the phase of the order parameter is the relevant quantity that varies between the grains of the system, leading to Josephson-type effects in the intergranular barriers due to the polycrystalline feature of this family of materials.
The coherence transition for the sample GdBa2Cu3O7-δ under the application of seven different electric transport currents was studied in this work. The sample was produced by the solid-state reaction and the resistive behavior was determined to perform the paraconductivity analysis and characterize granularity effects on the superconducting order parameter.
A genuinely critical region characterized by dynamic critical exponent z=4.5 was identified, similar to the value reported for the transition vortex glass – fluid. This paper proposes to identify three-dimensional Gaussian fluctuations in the paracoherent region in order to get a coherence length associated with Josephson effects produced by the granular barrier and to find a factor related with the Josephson current in function of the seven applied currents.
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Topic: CM - Characterization of Materials
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OPTICAL SENSOR BASED ON LAMELLAR DOUBLE HYDROXIDE (HDL) FOR THE DETECTION OF THE POLYPHENOL ACID CHLOROGENIC ACID IN COFFEE WASTE
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PARIS ELAINE CRISTINA 1, DONIZETTE MALAFATTI JOÃO OTÁVIO 2, NASCIMENTO ANDRESSA CRISTINA DE ALMEIDA 3, MATTOSO LUIZ HENRIQUE CAPPARELLI 4,
1 Embrapa, 2 Embrapa Instrumentação , 3 Federal University of São Carlos, 4 Embrapa Instrumentação,
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Email: luiz.mattoso@embrapa.br
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Abstract: The high presence of contaminants in the environment has raised awareness of the impact on ecosystem life. Different organic and inorganic molecules can potentially cause genomic mutations, occasioning disease and death. Among these possible pollutants are polyphenols, naturally found in plants and fruits, which in high amounts, may present significant toxicity. Chlorogenic acid (CCA) is an example found in wastewater from agro-industrial processing such as coffee. In this sense, it is necessary to monitor these effluents to ensure the proper return to the environment with the least possible impact. Therefore, the investigation for optical sensors that detect these polyphenols in the field becomes attractive for their ease of use, real-time response, lower cost, and minimization of steps compared to traditional analytical techniques. In the present work, we sought to evaluate the use of lamellar double hydroxides (LDH) modified with (3-Aminopropyl)triethoxysilane (APTES) as a sensing platform for chlorogenic acid. The modification process in ethane solution under-refluxed for 24 h in an oil bath. Concerning the detection of ACG, a phosphate buffer suspension (pH 7) containing 2 mg of LDH-APTES was used. In the assay, the concentration of ACG between 0.2 - 2 µg mL-1 was evaluated. Also, the sensitivity and selectivity effect against caffeic acid and cinnamic acid was evaluated. The results were observed using fluorescence and ultraviolet-visible spectroscopy. In the results, it was possible to follow that in the presence of ACG, the solution containing LDH-APTES changed from translucent to a yellowish coloration. Furthermore, it was possible to verify that by increasing the concentration of ACG, there was more significant evidence of color change. Additionally, in front of cinnamic acid and caffeic acid, the LDH-APTES did not show visual optical changes. Thus, the present work made it possible to obtain a promising sensor that allows a quick response and easy understanding for detecting a polyphenol present in water used in agro-industrial treatment.
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Topic: CM - Characterization of Materials
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POTENTIAL OF DODECYLAMINE-FUNCTIONALIZED GRAPHENE OXIDE (GO@DDA) AS A CO2 CAPTURE MATERIAL.
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PÉREZ RODRIGUEZ ELCY MARIANA 1, CEPEDA MARÍN GLADYS ROCÍO 2, CABANZO HERNÁNDEZ RAFAEL 3, MEJÍA OSPINO ENRIQUE 4, PORRAS GALVIS VICTOR ALBERTO 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Satander.,
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Email: vialpoga@gmail.com
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Abstract: The emission of carbon dioxide (CO2) is once of the greatest environmental challenges of our era, since its accumulation in the atmosphere is one of the main causes of climate change. Globally, China is the largest producer of CO2 emissions per year with 11,472 million tons (Mt), followed by the United States with 5,007 Mt; India with 2,709 Mt and Russia with 1,755 Mt; in this list Colombia ranks 43rd in annual CO2 emissions and fourth in Latin America with 91.7 Mt (Ritchie, 2021). The energy sector is the largest polluter in the world (76%), followed by agriculture including livestock (12%) and the chemical industry (5.9%), which results in the release of large amounts of CO2 into the atmosphere, generating global impacts such as: the generation of greenhouse gases, acidification of the oceans and changes in biodiversity, impacting the environment, the economy and society in general, this is why it is important to take measures to reduce CO2 emissions and mitigate these impacts to ensure a sustainable future (Emissions by source: Which sectors generate the most emissions?, n.d.).
To achieve efficient CO2 capture, support materials with large surface area and porosity are needed, these supports are functionalized with amines which are molecules derived from ammonia in which part of the hydrogen is replaced by a carbonate grouping as a consequence of the acid-base reaction of the adsorbate with the amino groups, therefore, the functionalized materials possess the properties of both components (an amine and a support). In the last decade, multiple combinations of support and adsorbent materials have been used obtaining diverse results in CO2 adsorption efficiency, as in a study conducted by Bouhadjar Boukoussa in 2019 where he uses mesoporous silica functionalized with triamine achieving an adsorption capacity of 3.2 mmol/g; another study by James C. Fisher in 2009 shows how beta zeolite functionalized with TEPA achieves an adsorption capacity of 2.9 mmol/g and finally, Yizhu Kuang in 2019 uses polyacrylonitrile fibers functionalized with TETA achieving an adsorption capacity of 5.44 mmol/g. On the other hand, carbon-based materials doped with Nitrogen are the ones that have shown the best efficiency with respect to CO2 adsorption, as shown in the study conducted by Jian-Cheng Geng in 2019 where he used porous carbons doped with Nitrogen (NPC) achieving an adsorption capacity of 6.9 mmol/g, which is why in this study we seek to evaluate a graphene oxide (GO) functionalized with dodecylamine (GO@DDA).
GO is a monomolecular layer of graphite oxide, whose lamellar structure consists mainly of carbons with bonds that change hybridization from sp2 to sp3 by the formation of covalent bonds with oxygen atoms coming from carbonyl, carboxyl, hydroxyl and epoxide functional groups, formed during the oxidation process of graphite (Dimiev & Tour, 2014) and is widely used due to its surface area, size, stability in aqueous solutions, resistance to thermal degradation and tensile strength, on the other hand DDA is a primary amine bonded to a long chain of twelve carbons, it is highly soluble in organic solvents of low polarity or totally apolar, with high thermal stability and great capacity of absorption of solids in suspension.
In this work a synthesis route was carried out where GO was obtained by the modified Hummers method and functionalized with DDA by amidation and nucleophilic substitution reactions, for this an aqueous dispersion of GO was taken which was placed in a reflux assembly at 380 rpm and 60°C; on the other hand, a solution of 1.5 g of DDA in ethanol was prepared at room temperature with constant agitation. Once the temperature of the GO solution reached 60°C, 10 ml of the DDA solution was added every 10 minutes and the conditions were maintained for a reaction time of 24 hours. Then the obtained material was frozen and lyophilized in order to have the material in solid form for its later characterization.
The material obtained was characterized by FT-IR spectroscopy which showed bands of the functional groups associated with GO and DDA; to determine the particle size distribution and stability of the material in solution, the dynamic light scattering (DLS) technique was used; Additionally, a thermogravimetric analysis (TGA) was performed to show the physical and chemical properties of the material as a function of temperature and finally, adsorption isotherms were performed to establish the adsorption capacity of CO2 ; with the results obtained from this research it was possible to establish GO@DDA as a material with a promising potential for the capture of CO2.
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Topic: CM - Characterization of Materials
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PRELIMINARY STUDY USING RAMAN SPECTROSCOPY FOR IDENTIFIED MPS INGESTED BY ZOOPLANKTON IN COLOMBIA'S CARIBBEAN REGION.
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CALDERÓN CASCAVITA LEIDY XIMENA 1, CABANZO HERNÁNDEZ RAFAEL 2, CORAL CHAMORRO LAURA SOFÍA 3, RUIZ JIMENEZ JENNY ALEJANDRA 4, CAPUTO CUETO LULY 5, BENAVIDES SERRATO MILENA 6, RODRIGUEZ PINILLA QUERUBÍN 7, CRIALES HERNANDEZ MARÍA ISABEL 8,
1 Universidad Industrial de Santander , 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 PNN Corales del Rosario y San Bernardo, 6 PNN corales de profundidad, 7 PNN Corales de Profundidad, 8 Universidad Nacional ,
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Email: micrialesh@unal.edu.co
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Abstract: Microplastics (MPs) are small plastic fragments ranging in size from 1 to 5,000 µm, originating from the chemical or physical degradation of larger plastic products or intentionally manufactured for incorporation into personal hygiene products, detergents, and so forth. These MPs represent a growing threat to marine ecosystems, but their impact on marine protected areas (MPA) remains poorly understood. This study highlights preliminary results obtained through the use of Raman spectroscopy, which allows the chemical identification of MPs ingested by zooplankton. The sampling was carried out during the dry season of March 2022 in two important AMP located in the Caribbean region of Colombia. These results contribute substantially to our understanding of microplastic dynamics in these invaluable marine protected environments.
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Topic: CM - Characterization of Materials
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SYNTHETIC HYDROXYAPATITE COATINGS DOPED WITH COPPER IONS
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BOHORQUEZ SANTIAGO LEONARDO 1,
1 Universidad Tecnologica De Pereira,
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Email: lbohorquez@utp.edu.co
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Abstract: The coating of metallic materials is a topic that has aroused great interest among researchers nowadays due to its high potential for medical applications. Hydroxyapatite is one of the most promising materials in this field due to its bioactive, biocompatible, and non-toxic properties [1], in addition to its chemical composition like human bone and its ability to chemically bond to bone [5], making it an ideal material for medical applications. However, hydroxyapatite has limitations as a raw material when it is used in areas subject to mechanical stress due to its fragility. To address this problem, materials such as titanium, steel, and alloys used in stressful situations can be coated [2]. Hydroxyapatite coatings can improve the osteointegration of implants and reduce the body rejection rate [6][7]. Currently, research is focused on improving the properties of hydroxyapatite by including chemical elements and synthesis techniques. Copper is one of the most attractive elements for coatings because it is an essential element in human metabolism, and it has been shown to have beneficial properties for bone health and angiogenesis [5], such as low cytotoxicity, antibacterial behavior, and biocompatibility [3]. Copper ions can promote the proliferation of human endothelial cells and the differentiation of mesenchymal stem cells towards the osteogenic phenotype [5]. Moreover, it has been shown that copper can inhibit the activity of osteoclasts and stimulate the aggregation of elastin fibers in mature fibers, promoting the deposition of the elastin matrix [5]. The incorporation of copper ions into the hydroxyapatite matrix could improve the mechanical integrity and antibacterial capacity of coatings for biomedical applications [4]. With this in mind, the developed work studied the effect of the incorporation of copper metal ions in hydroxyapatite coatings on silicon substrates by laser ablation technique and their respective characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). XRD characterization was used to determine the crystalline phases and changes in the full width at half-maximum (FWHM) of hydroxyapatite coatings, resulting in HAp and HApCu coatings being crystalline and mainly composed of hydroxyapatite. SEM images showed that the coatings are composed of micrometer and submicrometer-sized particles. Additionally, Energy-dispersive X-ray spectroscopy (EDS) analysis was performed to visualize the chemical composition of the samples and monitor changes in calcium, phosphorus, and copper concentrations in the coatings. To study the vibrational states of hydroxyapatite coatings, FTIR characterization was performed, where the characteristic bands of functional groups present in HAp and HApCu coatings were observed. From the above, it was concluded that analyzing XRD characterization, the incorporation of copper affects the size of hydroxyapatite crystals since the crystal size increases when copper is incorporated regardless of the number of copper threads used. Analyzing SEM, the deposition is given in a homogeneous way with micrometer-sized granules independently of the incorporation of copper.
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Topic: CM - Characterization of Materials
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TRANSPARENCY IN INSECTS: A STUDY OF THE PHYSICOCHEMICAL, OPTICAL, AND MORPHOLOGICAL FACTORS
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PEREYRA MARIANA 1, BENTANCUR-VIGLIONE GABRIELA 2, MARTINEZ JUAN PEDRO 3, FAGÚNDEZ PABLO 4, VALENTE PAULO 5, PEREYRA JAVIER 6, MORELLI ENRIQUE 7, MAROTTI RICARDO 8, DALCHIELE ENRIQUE 9,
1 Universidad de la República , 2 Sección Entomología, Instituto de Biología, Facultad de Ciencias, Universidad de la República, 3 Instituto de Física, Facultad de Ingeniería, Universidad de la República, 4 Unidad de Bioquímica Analítica, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, 5 Instituto de Física, Facultad de Ingeniería, Universidad de la República, 6 Instituto de Física, Facultad de Ingeniería, Universidad de la República, 7 Sección Entomología, Instituto de Biología, Facultad de Ciencias, Universidad de la República, 8 Instituto de Física, Facultad de Ingeniería, Universidad de la República, 9 Instituto de Física, Facultad de Ingeniería, Universidad de la República,
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Email: dalchiel@fing.edu.uy
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Abstract: Nanostructures are natural features that occur in animals and plants at the nanometer scale and influence their functions. For example, nanostructures are responsible for the hydrophobicity of plant leaves and the structural color of butterfly and bird feathers, which have inspired many technological applications. However, nanostructures are also found in insects that have transparent surfaces, such as some butterfly wings. The role of nanostructures in transparency is controversial, it is unclear whether these nanostructures are essential for transparency or whether they depend on the chemical composition of the wing components. In this study, we investigate the nanostructures in the transparent wings of Episcada hymenaea, a native butterfly species that lacks scales on most of its wings. Using materials characterization techniques, we analyse the structural, optical, and chemical properties of the transparent region and identify the factors that contribute to transparency. We also compare our results with those of Heliconisa pagenstecheri, night moth specie with transparent wings. Our findings clarify the role of nanostructures in transparency and provides insights for biomimetic applications.
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Topic: CM - Characterization of Materials
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USE OF MINING TAILINGS SLUDGE AS A PERCENTAGE SUBSTITUTE FOR CEMENT IN THE DESIGN OF CONCRETE MIXTURE FOR THE PILOT CONSTRUCTION OF FOOTPRINT PLATE IN THE MUNICIPALITY OF VETAS, SANTANDER.
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CAYCEDO GARCIA MAYA SIAN 1, LÓPEZ BERNIER YARIAGNA CAROLINA 2, BUENO GÓMEZ HEIDY THAILIN 3, ARDILA REY JOSE DANIEL 4,
1 UDES UNIVERSIDAD DE SANTANDER, 2 UDES UNIVERSIDAD DE SANTANDER, 3 UDES UNIVERSIDAD DE SANTANDER, 4 UDES UNIVERSIDAD DE SANTNADER,
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Email: jos.ardila@mail.udes.edu.co
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Abstract: . Mining tailings make up the sterile part of the rock that is discarded after a process of extraction and concentration (beneficiation) of a mineral in order to obtain elements of economic interest. At the end of this process, large amounts of tailings are generated, which can become environmental liabilities if they are not treated properly. In order to minimize their environmental impact and give them a use, a physical chemical study is undertaken as well as a design of mixtures for the percentual replacement of cement by the sludge of the mining tailings produced by the mining company La ELSY LTDA of the municipality of Vetas of the department of Santander. The sludge is used as a substitute of the cementing agent used to produce type D concrete for the construction of footprints and works of art such as pavements, gutters, sewers, separators, pavers, etc, without directly affecting the strength and original properties of the clinker, such as: densities, normal consistency and setting time.
This project addresses responds to the need to continue with the production of green gold given that, in spite of having eliminated the use of heavy metals such as mercury and cyanide for the benefit of the gold as of seven years ago, , La Elsy manifests the problem of the environmental liabilities generated by the accumulation of tailings as well as the need for technical studies that validate the use of this inert material in the construction of civil infrastructure, giving it a use that would boost the region and increase its inhabitants’ quality of life. This research connects with the design of regeneration programs, which must integrate sustainability criteria and environmental best practices, aimed at minimizing potential negative impacts on the ecosystem structure and function of the moors as well as their derived ecosystem services. Likewise, this proposal harmonizes the fundamental rights to work and to a healthy environment, highlighting that they are not mutually exclusive, and that the conservation of the moor and the protection of the water resources are both compatible with the development of a mining activity focused on continuous improvement, the progressive implementation of environmental and social best practices and the strengthening of a governance for the conservation of the territory.
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Topic: EMSET - Education in Materials Science, Engineering, and Technology
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APPLIED RESEARCH AT THE "INSTITUCIÓN UNIVERSITARIA PASCUAL BRAVO", COLOMBIA
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MEJIA RESTREPO ERICA 1, PADILLA DIAZ MARIA INES 2, MUÑOZ EDWIN 3,
1 INSTITUCIÓN UNIVERSITARIA PASCUAL BRAVO, 2 INSTITUCIÓN UNIVERSITARIA PASCUAL BRAVO, 3 Institución Universitaria Pascual Bravo,
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Email: e.munoz@pascualbravo.edu.co
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Abstract: Applied research is defined as "the generation of knowledge with direct application and in the medium term in society or in the productive sector". In the case of the Pascual Bravo University Institution, it is addressed directly by the institutional research groups through systematic, methodical, and critical activities based on knowledge and practical and collaborative experience. With it, technology is created, developed, integrated, transformed, improved, and prototyped for use in different fields and for the generation of new processes, products, and services in response to the needs, trends, and opportunities of the local, national and international environment. in favor of technological progress and the improvement of the quality of life in society. The Applied Research model is based on the work of the Research Groups, currently, there are five (5) Institutional Research groups, which are mentioned below: "Grupo de Investigación e Innovación en Energía (GIIEN), Grupo de Investigación e Innovación Ambiental (GIIAM), Grupo de Investigación En Ciencias Electrónicas E Informáticas (GICEI), Grupo de Investigación en Calidad y Productividad (QUALIPRO), e ICONO". The first three groups are attached to the Faculty of Engineering and the next two to the Faculty of Production and Design, they carry out their work under established Research Lines (22 in total), consistent with the training objectives of the academic programs of both Faculties. The model raises several levels, positioning under the Research Groups, the Research Seedbeds, support for extracurricular and voluntary training at different academic levels: secondary and undergraduate; that are nourished and in turn feed the Research Groups, working in the Lines structured around the objects of technological knowledge of the Institution. This bidirectional link between Seedbeds and Groups allows students to train in research, and strengthen a critical, creative, and innovative spirit that responds to real problems in different sectors: Company, Community, and State. In addition to the above, in the model the actors are visualized, such as the training personnel: Seedbed Coordinators, administrative personnel: Group Leaders, and management personnel: Line and Articulation Leaders with teaching; all of them are fundamental figures in the model that allow an impact on academic curricula and guarantee the development of research. Finally, it is important to highlight that the applied research developed in the institution allows it to respond to the needs of the environment, generating productivity and business competitiveness, social well-being of the communities, and economic and sustainable development of the regions. Guaranteeing through the innovation, transfer, and services program (PITS) the transfer of knowledge generated in the research groups to society.
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Topic: EMSET - Education in Materials Science, Engineering, and Technology
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CHARACTERIZATION OF ENERGY FLUCTUATIONS IN AN ELECTRONIC SYSTEM CONNECTED TO A MAXWELL DEMON IMPLEMENTED WITH CMOS INVERTER PAIRS
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VEGA ORTEGA STEPHANY 1, JEREZ VERA JULIAN EDUARDO 2, MIRANDA MERCADO DAVID ALEJANDRO 3, QUINTERO GRAUT JORGE ANDRÉS 4,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander,
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Email: jorge2228523@correo.uis.edu.co
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Abstract: The energy in an electronic system is determined by the potential difference and the electrical charge carriers on it. In the case of CMOS transistors, the electrical charge carriers may be electrons or holes, which may be subjected to a potential difference imposed by the connection of the electronic system to an external voltage source. Assuming an ideal constant voltage source, the imposed potential difference can be considered to be a time-invariant constant, i.e., fluctuations-free. However, electrons, or holes, interacting with the external electric potential may manifest fluctuations in their energy, e.g., due to thermal effects. Consequently, the energy of charge carriers can be modeled as a random variable with which a standard deviation is associated, characterizing their fluctuations. Recently, Freitas and Esposito \cite{Freitas2022} demonstrated that a CMOS inverter pair can be configured as Maxwell's daemon, thus allowing the study in the laboratory of out-of-equilibrium processes that also exhibit the atypical phenomenon associated with such daemon. In this sense, by connecting the electronic system to the Maxwell daemon, its behavior is altered, and the effects of this on the system states can be studied. In this work, we report the implementation of a CMOS electronic system with a Freitas-Esposito Maxwell daemon, which was characterized by measurements long enough in time to capture the statistical information of the system. Among the results observed in this study, two stand out: first, the observation of fluctuations in the potential difference consistent with those expected in a Brownian motion and second, the observation of two energy states for conditions of low external excitation or even in the absence of external excitation.
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Topic: EMSET - Education in Materials Science, Engineering, and Technology
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CRACK GROWTH ANALYSIS USING THE DUAL BOUNDARY ELEMENT METHOD, AN APPLICATION IN MATLAB
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MANTILLA VILLALOBOS JAIRO ANDRÉS 1, CRISTANCHO PERILLA ROBIN ALEXIS 2, BOHORQUEZ BECERRA OSCAR RODOLFO 3, MARTÍNEZ MANUEL DEL JESÚS 4,
1 Universidad industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad industrial de Santander,
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Email: mjmartin@uis.edu.co
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Abstract: Integrity engineering predicts the service life of mechanical components under fatigue conditions as a function of the number of load cycles, a parameter that depends on the reliability of the element and must be calculated. High reliability is usually achieved by fracture mechanics design, where controlled crack propagation is analyzed until element failure. It has been identified the necessity to make a transition from the traditional design model based on the Basquin curve to crack growth models that are well defined in the literature; however, the fracture mechanics analysis can only be developed analytically for simple geometries with simplifications, which then implies the use of numerical methods and advanced software in the design process. Existing fracture mechanics software can perform both analysis and visualization of the phenomenon by highly skilled users at high computational cost, proving that these computational packages are not an effective solution and can hardly be used as learning tools in the classroom. This work presents the development of software for crack growth analysis using the dual boundary element method, a method that reduces computational cost by solving only the element boundary and shows multiple advantages for solving complex geometries with mixed boundary conditions, applied to two-dimensional simulations in homogeneous and isotropic materials. The software has been designed as a modular MATLAB application with the goal of providing an easy-to-use tool for solving fatigue crack growth simulation problems. The results suggest that an easily portable software has been developed that can be used without MATLAB, is suitable for the generation of new simulations in research and teaching, allows the visualization of the propagation phenomenon and the fundamental variables in crack growth analysis, and presents a logical sequence in the use of numerical methods. The simulations were validated with experimental data and with different simulations using the finite element method. Finally, the shortcomings and future perspectives are discussed.
Keywords: Computational Solid Mechanics, Dual Boundary Element Method, Fracture Mechanics, Fatigue Crack Growth.
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Topic: EMSET - Education in Materials Science, Engineering, and Technology
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DIDÁCTICA E INNOVACIÓN CURRICULAR EN LA FACULTAD DE INGENIERÍA
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DUEÑAS RAMÍREZ LEIDY MARCELA 1, ORTIZ VÁSQUEZ LUISA FERNANDA 2, PENAGOS SUAREZ CRISITAN ALEJANDRO 3, PALOMEQUE MARTÍNEZ JULIO ULISES 4,
1 Corporación Universitaria Minuto de Dios, 2 Fundación FORISTOM, 3 Corporación Universitaria Minuto de Dios , 4 Corporación Universitaria Minuto de Dios,
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Email: julio.palomeque.m@uniminuto.edu.co
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Abstract: The classroom is the appropriate space to form and strengthen learning communities of students and teachers, from different areas of knowledge where research processes can be carried out as a tool for learning, involving the student actively in the process. This model has been affected by the pandemic generated by COVID 19. Therefore, this work sought to design a didactic tool supported by the processes of scientific research for the transfer of knowledge in the classroom; during the learning of mathematics, statistics and physics. A research applied in the classroom was proposed under a quali-quantitative methodology that used three methods of data collection: observation, case study and survey. These three methods allowed consolidating the necessary information to establish a methodological tool based on the steps and processes of scientific research as a means not only to generate new knowledge, but also to appropriate it through the sharing and construction of knowledge between the student and the teacher. The tool has been implemented by several professors of the Corporación Universitaria Minuto de Dios in the city of Bello in Antioquia, Colombia. The main results obtained have been a validation of the students' knowledge before the academic community of the institution through exhibition days by means of research posters where the students orally give an account of the knowledge acquired in class, applied to topics applied by each student. A web page was also developed to support the application process of the didactic tool, so that teachers and students could have an online guidance on how to approach and apply the tool in class. This strategy has already started to be implemented in other sites of the institution and the results are expected to be applied in other geographical contexts.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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CFD MODELLING AND SENSITIVITY STUDY OF THE VAPOUR ABSORPTION IN A BUBBLE DOUBLE PIPE ABSORBER
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AMARIS CARLOS 1, ZAPATA ANDRES 2,
1 Universidad Industrial de Santander, 2 Universidad del Valle,
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Email: andres.zapata@correounivalle.edu.co
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Abstract: Absorption heat pump technologies are called to play a relevant role in the energy transition given their nature of sustainable and environmentally friendly emerging options when driven by solar energy or waste energy. However, they require further development to compete with mechanical heat pump technologies. Absorption heat pumps, in their basic configuration, consist mainly of an evaporator, an expansion valve, a condenser, a generator, a solution pump, and an absorber. The absorber is identified as the most critical component because depending on how intense the vapour mass transfer is in this component, it affects the cooling capacity and performance of the system. Since the absorption process is exothermic, both mass and heat transfer occur simultaneously resulting in a complex phenomenon. Moreover, the bubble absorption mode allows better exchange interphase in comparison to falling film or adiabatic absorption mode configurations.
The present investigation aims to model the bubble absorption process performance in an aluminium double pipe absorber of 1-meter length using a mixture of ammonia\lithium nitrate. The ammonia\lithium nitrate mixture is identified as a promising alternative to conventional working fluids and has a great potential for solar air-conditioning applications. The CFD model test section consists of a vertical aluminium double pipe absorber with smooth surfaces where the mixture and ammonia vapour flow upward in the inner tube while the cooling water flows downward in the annulus side. In this study, the methodology followed to built-up a CFD model of the absorption process is presented and validated. Moreover, a sensitivity study is also presented considering the effect of the operating parameters on absorber performance indicators such as absorption mass flux, mass transfer coefficient, and solution heat transfer coefficient. Results mainly indicate that the CFD model adequately simulates the effect of the cooling water flow and solution mass flow. Results also show that the heat and mass transfer parameters improve as the solution mass flow is risen and the cooling water temperature is reduced. The developed CFD model helps to avoid costly experimentation and will be used to design bubble absorbers where the vapour absorption process can be enhanced using internal pipes with inner advanced surfaces of different material characteristics.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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CHARACTERIZATION OF MECHANICAL PROPERTIES OF PORCINE BONE USING FINITE ELEMENT MODELS AND EXPERIMENTAL TESTS
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HERNÁNDEZ SALAZAR CRISTIAN ANDRÉS 1, VILLEGAS BERMUDEZ DIEGO FERNANDO 2, GONZÁLEZ-ESTRADA OCTAVIO ANDRÉS 3,
1 Universidad Industrial de Santander, 2 Universidad industrial de Santander, 3 Universidad Industrial de Santander,
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Email: agonzale@uis.edu.co
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Abstract: Finite element models have facilitated significant advances in the field of bioengineering, and are used to describe and characterize tissues, study the effect of forces on different parts of the body, and design materials to be used in prostheses. The study with pigs has allowed us to advance in the field of medicine, as pig tissues have a similarity to humans, allowing for better model results. In this work, experimental data obtained from compression tests of porcine femurs are analyzed and compared with numerical models developed through finite element analysis. Additionally, experimental tests were conducted in the laboratory, performing axial compression tests on porcine femurs to obtain mechanical properties and determine load conditions, stresses, and strains in the elastic range. On the other hand, the leg bones of pigs obtained through standard computed tomography (CT) scans were segmented. Subsequently, finite element segmentation was analyzed, and bone properties were assigned to voxels considering Hounsfield units (HU) for the porcine femur. In each voxel, an isotropic model was considered for trabecular or cortical tissue according to the material. Evaluation through the finite element model allows us to determine the failure zone of each geometry, as well as stress distribution. Finally, experimental data is compared with that obtained through finite element analysis. A good correlation was shown in the displacements of the three sections of the porcine femur analyzed. Specifically, a difference of only 0.3% was observed in cortical tissues, while differences of 2% and 1% were observed in trabecular-cortical and trabecular tissues, respectively. The proposed work includes the representation of the functionally graded behavior of bone, which will help to obtain more accurate medical results, contributing to medicine.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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COMPARATIVE AXIAL COMPRESSION TESTING OF PORCINE VERTEBRAE BY LABORATORY TESTING AND FINITE ELEMENT ANALYSIS
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HERNÁNDEZ SALAZAR CRISTIAN ANDRÉS 1, CHAMORRO GARCÍA CAMILO ENRIQUE 2, GONZÁLEZ-ESTRADA OCTAVIO ANDRÉS 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: agonzale@uis.edu.co
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Abstract: The study of pig bones, due to their similarity with human tissues, has allowed for the development, updating, and selection of technological tools that aid in the improvement of diagnosing diseases and injuries that may affect the skeletal system. Radiomic techniques involving diagnostic medical image segmentation, along with finite element analysis, enable the detailed study of bone damage, loss of density, and mechanical functionality, which is a significant advancement in personalized medicine. In this study, laboratory tests are conducted on axial loads to L3-L6 pig vertebrae, their mechanical properties are characterized, and the maximum loads that they can withstand in the elastic zone are determined. Furthermore, 3D models are generated through the segmentation of computed tomography images of the vertebrae. A digital shadow of the vertebra is constructed by assigning an anisotropic material model to the reconstructed geometry. Subsequently, finite element analysis is performed to determine the elastic characteristics, strength, and displacement. Once the information is obtained, it is compared between the experimental data and the numerical model, showing a good correlation, with a difference of less than 0.8% in Young's modulus and 1.53% in displacement. The proposed methodology will aid in obtaining more precise medical results, using models that will serve as a reference for diagnosis.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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CRITICAL TEMPERATURE AND HYSTERESIS LOOPS OF AN ISING-TYPE FERROMAGNETIC SYSTEM OF SPINS 1 AND 2: A MONTE CARLO STUDY
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DE LA ESPRIELLA VÉLEZ NICOLÁS 1, MADERA JULIO CESAR 2, ALCALÁ VARILLA LUIS ARTURO 3,
1 UNIVERSIDAD DE CÓRDOBA, 2 Universidad del Sinú, 3 Universidad de Córdoba - Colombia,
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Email: lalcala@correo.unicordoba.edu.co
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Abstract: In the present work, the thermomagnetic properties of a ferromagnetic system of integer magnetic moments S = ±2, ±1, 0 and Q = ±1, 0 were analyzed by means of Monte Carlo simulation techniques and a thermal bath algorithm. The ferromagnet was configured through a two-dimensional square lattice, considering nearest-neighbors exchange couplings between S and Q spins (Si → Qj), next-nearest-neighbors exchange couplings between S-type spins (Si → Sj), and interactions with an external magnetic field h. The effects of the next-nearest-neighbor exchange parameter (J2) and a magnetic field h on the phase diagrams at finite temperature of the magnetizations, the magnetic susceptibility, and the critical temperature were analyzed, as well as the hysteresis behavior for different temperature values. The critical temperature (TC) is proportional to |h| and |J2|.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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EFFECTS OF EXCHANGE AND ANISOTROPY INTERACTIONS ON THE COMPENSATION AND HYSTERESIS BEHAVIORS OF A FERRIMAGNET OF (7/2,2)-SPINS
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DE LA ESPRIELLA VÉLEZ NICOLÁS 1, MADERA JULIO CESAR 2, SÁNCHEZ LUÍS CARLOS 3,
1 UNIVERSIDAD DE CÓRDOBA, 2 Universidad del Sinú, 3 Universidad de Córdoba,
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Email: lsanchezpacheco@gmail.com
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Abstract: By means of Monte Carlo simulations, the thermomagnetic properties of a ferrimagnetic system with spins of values Q=7/2 and S=3/2 alternating on a square lattice are investigated. The Hamiltonian of interactions of the model contains antiferromagnetic and ferromagnetic next-nearest-neighbor couplings, as well as magnetocrystalline anisotropy in each of the sublattices composing the ferrimagnet. The effects of such interactions are reflected in the compensation, multiple hysteresis loops, and discontinuities phenomena in the magnetization phase diagrams. The positive increase of the exchange interaction generates discontinuous transitions in the system, and destroys the spin compensation points. Finally, phase diagrams of the critical, spin compensation, and discontinuous temperatures as a function of exchange and anisotropic couplings are presented in the (J3,T) (D3,T) planes.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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FIRST-PRINCIPLES CALCULATIONS OF THE STRUCTURAL AND ELECTRONIC PROPERTIES OF GAAS/INAS INTERFACES
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ARELLANO IVAN 1, GIL-REBAZA ARLES 2, AMAYA-RONCANCIO SEBASTIAN 3, RESTREPO PARRA ELISABETH 4,
1 Technological University of Pereira, 2 Instituto de Física de La Plata, Universidad Nacional de La Plata, 3 Universidad de la Costa, 4 Universidad Nacional de Colombia,
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Email: erestrepopa@unal.edu.co
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Abstract: The interfaces are formed when two different semiconductors are brought into contact with each other. The importance of GaAs/InAs interfaces are related with the fact that they exhibit unique structure and electronic properties that can be used to design and fabricate novel electronic and optoelectronic devices. In this study, we present the structural, electronic, and energetic properties of (GaAs)m/(InAs)n (m, n =1 to 3) interfaces using ab-initio calculations within the Density Functional Theory. The electron-ion interaction is described with an ultrasoft scalar relativistic pseudopotential. Within the Generalized Gradient Approximation (GGA), the PBE exchange-correlation functional is used. The kinetic cutoff energy (Ecutwfc) is set at 70 Ry and the cutoff for the augmented density is set at 700 Ry after convergence calculations. All the structures are energy minimized to find the optimal lattice constant and optimal heigh (m, n). Subsequently, a geometric relaxation of all atomic positions and lattice parameters is performed to ensure the energy minimization. Cohesive and formation energies are calculated to understand energetic stability. Moreover, Density of States and band structure calculations are presented to understand the electronic behavior of the studied interfaces.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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INFLUENCE OF SURFACE DEFECTS ON THE VORTEX PENETRATION AND ARRANGEMENT AT MESOSCOPIC SUPERCONDUCTING SAMPLES
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PRESOTTO ALICE 1, BARBA ORTEGA JOSE JOSE 2, ZADOROSNY RAFAEL 3,
1 Universidade Estadual Paulista (UNESP), Faculdade de Engenharia, Ilha Solteira, São Paulo, Brazil, 2 Universidad Nacional de Colombia, 3 Universidade Estadual Paulista (UNESP), Faculdade de Engenharia, Ilha Solteira, São Paulo, Brazil,
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Email: rafael.zadorosny@unesp.br
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Abstract: All superconductor’s applications lie on carry dissipationless current. However, in the presence of external magnetic fields, including the self-field, vortices penetrate the sample, and their dissipative motion generates resistive states. Thus, once the superconductive state survives for higher magnetic fields due to the presence of vortices, those specimens cannot move to increase the critical current density. Then, in this work, we studied the influence of surface defects on the vortex penetration and arrangement at square mesoscopic superconducting materials using the Time-dependent Guinzburg-Landau (TDGL) theory. The lateral size of the samples was L=10ξ(0), with five defects on one of the borders. Besides the defects’ width being set as 0.250ξ(0), their positions and lengths varied. We also used a homogeneous system (pristine) to compare the results. Thus, we studied the dynamics of vortex penetrations, focusing mainly on the penetrations that occurred in the region with the defects. The main result we obtained is that, due to the confinement effects present in mesoscopic superconductors, the presence of defects in one of the samples’ edges is not a necessary condition for the vortices to penetrate this region.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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MOLECULAR DYNAMICS STUDY OF OIL/WATER SEPARATION BY GRAPHENE OXIDE AND ALKYLAMINE-MODIFIED GRAPHENE OXIDE MEMBRANES
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MEJÍA OSPINO ENRIQUE 1, FORERO CHRISTIAN 2, MUÑOZ LEONARDO 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: leomunozr84@gmail.com
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Abstract: Studies have shown that the use of alkylated graphene oxide (GO-A) in filtration columns results in superior demulsification efficacy compared to graphene oxide (GO), indicating its potential for improving the oil-in-water separation process [1]. Molecular dynamics can be employed to explore the mechanism underlying the superior behavior of GO-A membranes in oil/water separation [2]. In this work, molecular dynamics simulations were employed to investigate the toluene/water separation process of GO and GO-A membranes under a gravity field. The variations in the interlayer spacing, offset, and gap of the membrane models were investigated. Moreover, the effect of the alkyl chain length on the structure of GO-A nanosheets was studied. Results indicate that increasing the gap and interlayer spacing of the membrane models decreases the filtration efficiency. However, the offset values did not show a significant effect on the filtration efficiency. The interaction potential energy profiles were calculated and it was found that the membranes strongly interact with toluene. As water molecules pass through the membrane, the interaction energy between the membranes and water increases, indicating effective separation of the oil and water phases. The lower interaction energy between GO-A and toluene, compared to that of GO and toluene, indicates that GO-A efficiently retains toluene molecules. The radial distribution functions of sp² carbons and alkyl carbons in the GO-A membrane systems were calculated to investigate their interaction with toluene. The results indicate that toluene interacts strongly with sp² carbons in the membrane.
References:
[1] S.N.C. Ortiz, R. Cabanzo, E. Mejía-Ospino, Crude oil/water emulsion separation using graphene oxide and amine-modified graphene oxide particles, Fuel 240 (2019) 162–168.
[2] Foroutan, M., Zahedi, H., Soleimani, E, Investigation of water-oil separation via graphene oxide membranes: a molecular dynamics study. Colloids Surf. A Physicochem. Eng. Asp. 555 (2018) 201–208.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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MUTUAL INFORMATION FOR PREDICTION OF RELEVANT PARAMETERS IN THE PEROVSKITE SOLAR CELL SYNTHESIS
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BOTERO LONDOÑO MÓNICA ANDREA 1, VELEZ SANCHEZ JEISSON EMILIO 2, SEPULVEDA SEPULVEDA FRANKLIN ALEXANDER 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: alexander.sepulveda@saber.uis.edu.co
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Abstract: Learning about those most relevant descriptors describing the synthesis of Perovskite solar cells could have a significant impact on improving their efficiency. Having this information could reduce time and resources during the synthesis procedure because it would permit to material scientists to focus on those most influential variables.
Machine learning techniques (ML) can be used for this purpose. In particular, there are two approaches: a) using feature subset selection techniques and, b) using statistical association measures. In the first case, the selected variables and the relevance measure they provide depends on the kind of ML model used. That is, the result depends on the type and complexity of the selected model among those possibilities offered by the ML field. By contrast, statistical association measures provide a single result because they do not incorporate the use of particular models in their procedures, thus, their results are independent of the model.
Among statistical association measures, Pearson correlation coefficient and rank correlation measures such as Kendall's and Spearman's coefficients can be mentioned. Regarding Pearson, it is assumed that the relationship between the involved random variables is linear, which is rare, taking into account the complexity of this kind of phenomena. On the other hand, rank correlation measures work for nonlinear relationships, but only if the underlying function of the phenomenon is monotonic increasing or decreasing. By contrast, the mutual information (MI) measure does not suffer from these drawbacks.
In present work, we propose to use mutual information measure in order to quantify the amount of information contained in descriptor variables about synthesis process, in respect to perovskite solar cells performance parameters. The performance measures correspond to open-circuit voltage (Voc), Short Circuit Current Density (Jsc), Fill Factor (FF), and Power Conversion Efficiency (PCE). The mutual information measure (which quantifies the information that a descriptor contributes to the inference of performance parameter) is estimated by using a data set composed of more than 40,000 experimental observations about Perovskite cells.
In present work, we propose to use mutual information measure in order to quantify the amount of information contained in descriptor variables about synthesis, in respect to Perovskite solar cells performance parameters. The performance measures correspond to open-circuit voltage (Voc), Short Circuit Current Density (Jsc), Fill Factor (FF), and Power Conversion Efficiency (PCE). The mutual information measure (which quantifies the information that a descriptor contributes to the inference of performance parameter) is estimated by using a data set composed of more than 40,000 experimental observations
about Perovskite cells.
As a result, it was found that those variables that could contribute the most to PCE prediction are: i) concentrations of elements used to form the perovskite thin film; ii) the materials used to form the back contact and the hole transport layer (HTL); and, iii) Perovskite’s thickness. Each of these variables provides between 1.2 bits and 1.8 bits of information. Taking into account that the amount of information corresponding to PCE resulted in 4.33 bits, it can be infered that the effect of these variables is considerable.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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PATTERN ANALYSIS IN METEOROLOGICAL AND BIOTIC VARIABLES FOR MODELING PEST RISKS IN AVOCADO CROPS USING MACHINE AND DEEP LEARNING
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RAMIREZ GUERRERO TOMAS ENRIQUE 1, HERNÁNDEZ PÉREZ MARIA ISABEL 2, TABARES BETANCUR MARTA SILVIA 3, VILLANUEVA EDUART 4, PEÑA PALACIO ALEJANDRO 5,
1 Universidad EAFIT, 2 Universidad EAFIT, 3 Universidad EAFIT, 4 Universidad EAFIT, 5 Universidad EAFIT,
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Email: japena@eafit.edu.co
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Abstract: Crops in agriculture are affected by long-term trends in precipitation and average temperatures, disturbances during specific phases of plant development, and pest outbreaks due to weather variations. Improper pest management in Hass avocado crops can lead to fruit production losses and, in some cases, quarantine phytosanitary measures. These measures have a high-negative impact on avocado producers in Colombia and the Andean region, who currently produce approximately 1.93 tons per year and supply 37% of avocados sold in the European market. This paper presents a descriptive analysis to identify patterns related to climate changes (temperature and air humidity, precipitation, wind speed and direction, solar radiation) and tree phytosanitary status in a Hass avocado crop from eastern Antioquia, Colombia. Using the Analytics Solutions Unified Method in Data Mining, crop data collected periodically were processed: climate data are collected every 15 minutes through a weather station installed in the study area; phytosanitary data are collected every 15 days by monitoring and visual inspection of avocado trees. From this analysis, the aim is to have the basis to create a deep or machine learning model capable of determining the variations that lead to moderate and high levels of affectation, for the estimation of pest risk and the planning of its management in avocado crops. Results show the trend between pest damage and variations in temperature and humidity in the area, associated with soil conditions, from patterns since the actual event present in the crop. Thus, producers can conduct proper pest risk analysis, which is possible through the analysis of patterns in the physical climatic variables and biotic variables. These patterns will allow for estimating the behavior of pests in the avocado crop, to carry out proper pest risk management.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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PATTERN RECOGNITION OF TWO-PHASE FLOW IN VERTICAL PIPES USING ARTIFICIAL INTELLIGENCE TECHNIQUES
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GONZÁLEZ-ESTRADA OCTAVIO ANDRÉS 1, RUIZ DÍAZ CARLOS 2, QUISPE BRAYAN 3,
1 Universidad Industrial de Santander, 2 Universidad de Sao Paulo, 3 Universidad Industrial de Santander,
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Email: brayan.nos@hotmail.com
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Abstract: The structuring of flow maps in the hydrocarbons industry has been developed from empirical correlations that integrate flow characteristics, such as superficial velocities and volumetric fractions, together with physical properties of the substances under analysis such as density and viscosity, in addition to using geometric parameters such as inclination and internal diameter of the pipes. Currently, technological advances have been developed that allow optimizing the flow pattern identification process, based on the implementation of artificial intelligence techniques, due to the fact that there are limitations to monitor the flow pattern generated inside the pipelines in offshore platforms, given the extreme working conditions that occur there. In this study, a long- and short-term memory (LSTM) recurrent neural network was developed, capable of predicting flow patterns generated inside vertical pipes. The LSTM network was trained and subsequently validated with the information contained in a database obtained from the literature, showing an error generated in the model predictions of less than 1%.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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SIMULATION OF ROBOTS SWARM AGGREGATION USING THE BEECLUST METHOD
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RIOS DIAZ YENNIFER YULIANA 1, ACEVEDO-PATINO OSCAR 2, GARCIA LUIS 3,
1 Universidad Industrial de Santander, 2 Universidad Tecnológica de Bolívar, 3 Universidad Simón Bolívar-Audacia,
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Email: luis.garciag@unisimon.edu.co
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Abstract: La robótica de enjambres estudia el comportamiento de un grupo de robots homogéneos que colaboran para alcanzar un objetivo común. El desarrollo de esta área de la robótica ha abierto la posibilidad de resolver diferentes problemas de ingeniería, tales como, monitoreo de condiciones ambientales, reconocimiento de espacios, operaciones de búsqueda y rescate, entre otros. El diseño del controlador es uno de los principales desafíos, debido a que se debe definir el comportamiento individual de cada robot para lograr realizar la tarea a nivel de enjambre. Se han estudiado las características y propiedades de organismos vivos que presentan comportamiento de enjambre con el fin de abordar el desafío del diseño del controlador, es decir, definir el comportamiento individual de cada robot para lograr realizar la tarea a nivel de enjambre. Estos estudios han identificado comportamientos fundamentales, como la agregación, el cual puede ser considerado como un comportamiento esencial del enjambre debido a la frecuencia con la que aparece este comportamiento y debido a que se ha determinado que la agregación es un paso preliminar para el funcionamiento adecuado de otros comportamientos de enjambre. Este proyecto presenta un simulador desarrollado en Matlab con el propósito de estudiar cómo la agregación de robots puede ser guiada por las características del entorno, mediante el uso del algoritmo Beeclust. El simulador permite estudiar el proceso de agregación del enjambre y los factores que afectan su eficiencia. Se presentan resultados de simulaciones realizadas en diferentes escenarios ambientales y con diferentes características del enjambre, así como dos variantes del algoritmo original que buscan mejorar su eficiencia en la agregación. En algunos casos, se comparan los resultados obtenidos con los de otros trabajos similares.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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SIMULATION OF THE ELECTRONIC AND STRUCTURAL PROPERTIES OF GAMXAS1-X DOPED WITH BI, P, SB ATOMS FOR POSSIBLE APPLICATIONS IN SOLAR CELLS
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LÓPEZ RENDÓN MARÍA DEL MAR 1, ARELLANO IVAN 2, AMAYA-RONCANCIO SEBASTIAN 3, RESTREPO PARRA ELISABETH 4,
1 Universidad Tecnológica de Pereira, 2 Technological University of Pereira, 3 Universidad de la Costa, 4 Universidad Nacional de Colombia,
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Email: erestrepopa@unal.edu.co
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Abstract: In this study, first-principles calculations are performed using Density Functional Theory (DFT), to simulate the electronic and structural properties of the semiconductors G〖aM〗_x As_(x-1), where x=0,0.25,0.50,0.75,1 and M=Bi,P, Sb, determining the viability of each compound for use in a solar cell. The electron-ion interaction was described with an ultrasoft scalar relativistic pseudopotential. Within the Generalized Gradient Approximation (GGA), the PBE exchange-correlation was used. The lattice parameter and the bulk modulus of all compounds were calculated by fitting the total energy versus volume data to the Birch-Murnaghan equation of state. The formation, cohesion, and substitutional energies of all systems are calculated. It is observed that the compounds GaP, G〖aBi〗_0.25 As_0.75, and G〖aSb〗_0.25 As_0.75 have the most stable structures and are more likely to form. Regarding the electronic properties, an analysis of the density of states (DOS), the projected density of states (PDOS), and band structure are performed to determine the value of the band gap and which systems exhibit a direct optical band gap. The compounds GaP_0.25 As_0.75 and G〖aP〗_0.75 As_0.25 have a medium bandgap, exhibiting the behavior of semiconductor materials. The compounds with Sb and Bi doping show a narrow band gap, whereas doping with P increases the band gap. All the studied systems presented a direct optical band gap.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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STATISTICAL TECHNIQUES BASED ON VARIANTS OF THE GEOMETRIC MEAN FILTER APPLIED TO 3-D PREPROCESSING OF COMPUTED TOMOGRAPHY MEDICAL IMAGES.
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VALBUENA PRADA OSCAR 1,
1 Universidad Simón Bolívar - sede Cúcuta,
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Email: oscar.valbuena@unisimon.edu.co
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Abstract: The study, treatment and processing of medical images is of special interest in the clinical and imaging context due to its importance and contributions in the field of medicine and bioengineering with special interest in clinical diagnosis. Likewise, computed tomography (MSCT) is one of the fastest growing imaging modalities in clinical diagnostics. However, the images present imperfections that affect the quality of the information present in the images and hinder the identification and monitoring of relevant pathologies in the issuance of a more accurate diagnosis. To reduce the impact of imperfections, such as noise and artifacts, a preprocessing stage was carried out by applying a set of statistical techniques based on variants of the geometric mean filter, which were compared, from the point of view of efficiency and effectiveness with classical statistical techniques that have been widely reported in medical image preprocessing. During this stage, 02 3-D databases (DB), one synthetic DB and one MSCT DB, were preprocessed. For the validation of the preprocessing techniques, a set of statistical metrics was applied for quantitative and qualitative evaluation by visual inspection of the images. The results showed that the variant of the geometric mean filter that considers the square of the arithmetic mean and the square of the variance obtained the best Score in the preprocessing with respect to the other techniques considered, with a time of 0.83±0.0010 minutes and window size 3x3x3.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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SUBSTITUTION OF TRADITIONAL MATERIALS WITH ORGANIC REINFORCEMENT COMPOSITES
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CRISTANCHO PERILLA ROBIN ALEXIS 1, PERTUZ COMAS ALBERTO DAVID 2, DIAZ BERMUDEZ LUIS FERNANDO 3, GARCÍA VARGAS LINA GABRIELA 4,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander,
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Email: lina2210387@correo.uis.edu.co
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Abstract: Currently, environmental sustainability has become one of the biggest global challenges. The production of goods and services has historically been associated with the generation of polluting emissions, waste, and other negative environmental impacts. In order to reverse this trend, multiple solutions have been proposed, including the implementation of composite materials made from recycled and organic materials. Composite materials are formed from a matrix with certain mechanical properties and a reinforcement with different properties that complement the behavior of the developed piece. These materials offer a series of advantages over conventional materials, such as greater strength, durability, lightness, and the possibility of adapting to different designs and shapes. However, they also presented some challenges in their implementation, such as the appropriate selection of the materials that would compose the composite, the optimization of its design, and the evaluation of its environmental impact. In this context, a research project was carried out that aimed to substitute conventional materials to improve employability in the manufacture of parts with composite materials. The project focused on the characterization and improvement of the strength and stiffness properties of a bicycle part, by selecting different natural fiber reinforcements and epoxy matrix. Three types of natural fibers were selected to be used as reinforcement: palm fiber, sugarcane fiber, and powdered lignin. These fibers were chosen for their high strength and stiffness, as well as for their renewable and biodegradable origin. The mechanical properties of the epoxy matrix composites reinforced with these fibers were compared with those of the conventional materials used in the manufacture of bicycle parts. To carry out the comparison, the bicycle part was modeled using SolidWorks software and simulations of the different composite materials were carried out. The results showed that the epoxy matrix composites reinforced with natural fibers had similar or even superior mechanical properties to those of conventional materials, depending on their anisotropic design. In addition to the comparison of the mechanical properties, an environmental impact analysis was carried out between the composite materials addressed and the conventional materials, in order to determine their environmental footprint and evaluate their impact on the environment. Thus, it was found that natural fiber composite materials had a lower environmental footprint compared to conventional materials. In this sense, research in composite materials remains a constantly evolving field, which seeks to improve the properties and characteristics of existing materials, as well as explore new alternatives for their use in different areas. From a sustainable perspective, the use of composite materials in the manufacture of parts and components offers a promising alternative to reduce the environmental footprint of the industry and promote more responsible practices with the environment. In conclusion, research in composite materials has made significant advances in recent decades, with the development of new materials and manufacturing techniques. These materials offer a wide variety of applications in different sectors. In addition, the incorporation of biodegradable and recyclable materials in composites promotes more sustainable and responsible practices with the environment.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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THERMAL DISTRIBUTION DURING FRICTION STIR WELDING OF POLYMERS USING THE FINITE ELEMENTS METHOD.
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RODRIGUEZ JUAN DAVID 1, MANTILLA VILLALOBOS JAIRO ANDRÉS 2, CRISTANCHO PERILLA ROBIN ALEXIS 3, BOHORQUEZ BECERRA OSCAR RODOLFO 4, RIOS DIAZ YENNIFER YULIANA 5,
1 Universidad Industrial de Santander, 2 Universidad industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Santander,
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Email: yeriosdi@uis.edu.co
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Abstract: Friction stir welding (FSW) is a solid-state joining process that uses a rotating tool formed by a pin that applies pressure to the surface of the workpiece, generates heat through friction, and leads to the plasticization of the materials. FSW has been well received due to its effectiveness in joining various types of materials with poor weldability and producing high-quality joints without melting the materials, however, little numerical research has been developed to improve the process and its implementation in thermoplastics. In this study, a three-dimensional (3-D) finite element (FE) model of FSW in the thermoplastic polymer polymethyl methacrylate (PMMA) was developed using ABAQUS software, making use of the Coupled Eulerian-Lagrangian Coupled (CEL) strategy, the Johnson-Cook law of materials, and the Coulomb law for friction. The parameters of feed rate and rotational speed of the tool were modified, being these the main variables of the FSW. Temperature distributions were obtained for the different configurations, which allowed us to analyze and identify the thermal affectation zones of the process. The data used in the simulation are data obtained from the bibliography.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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THERMO-PILLARS AS ANTI-PINNING CENTERS IN A SUPERCONDUCTING CUBE
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BARBA ORTEGA JOSE JOSE 1, MOSQUERA POLO ARIDAY 2, AGUIRRE TELLEZ CRISTIAN ANDRES 3,
1 Universidad Nacional de Colombia, 2 Universidad del Magdalena, 3 Universidade Federal de Mato Grosso,
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Email: cristian@fisica.ufmt.br
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Abstract: In the present work, we study the vortex matter in a superconducting in-homogeneus cube with a array of termo-pillars, the sample is immersed in a magnetic field and inside of a homogeneus termal bath. The presence of the thermo-pillars changes the vortex configuration in the superconducting cube considerably generating the confinement of the vortices in un-conventional configurations for a mono-band systems. We study the effect that the variation in temperature has on magnetic variables in these systemss. We analyze the magnetic response of the sampe with four and five termo-mopillars located in specific positions are considered. This study was carried out solving numerically the real three-dimensional Ginzburg-Landau equations.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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TRANSFER MATRIX METHOD IN MULTILAYER APPLICATIONS: A SIMULATION
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CASTIBLANCO SUAREZ RAUL EDGARDO 1, FERRERO ALEJANDRO 2, MENDEZ MERCHAN GERMAN ANIBAL 3,
1 Universidad Católica de Colombia, 2 Universidad Católica de Colombia, 3 Universidad Católica de Colombia,
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Email: gamendez@ucatolica.edu.co
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Abstract: This document analyzes the propagation of electromagnetic radiation through stratified media, which forms systems that are usually known as photonic crystals. A first analysis includes a system composed by a thin film deposited in a substrate. The method of transfer matrix was used in order to simulate the system and thus obtain the behavior of the reflectance and transmittance functions.
After extrapolating the transfer matrix method to include N stratified media, optical characteristics such as the band energy (forbidden energy) were obtained. In the current research, the method was applied to waveguides as a particular example; the influence of some parameters such as the dielectric constant (E), refractive index (n), thickness of the media (d) and frequency of the incident wave (w) on the energy gap was determined.
The simulation by means of the transfer matrix allowed to calculate the transmittance and reflectance of waveguide for systems with N media, whose thicknesses lie within the {10}^{-9}m regime, showing the permitted energy levels. Additionally, the simulation is a reliable tool in order to study the approximate behavior of radiation through waveguides, allowing us to adjust the aforementioned parameters and determine if whether or not exotic, unexpected, or significantly relevant phenomena, which are worth studying, arise.
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Topic: MSD - Modeling, Simulation, and Diagnostics
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TYPE-I SUPERCONDUCTIVTY: SPIKE VORTEX STATE
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BARBA ORTEGA JOSE JOSE 1, RINCÓN JOYA MIRYAM 2, AGUIRRE TELLEZ CRISTIAN ANDRES 3,
1 Universidad Nacional de Colombia, 2 Universidad Nacional de Colombia, 3 Universidade Federal de Mato Grosso,
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Email: cristian@fisica.ufmt.br
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Abstract: The spike vortex-state is a meta-stable state that is found lowering the magnetic fields near to the normal-superconducting transition in conventional type I samples for a determined Ginzburg-Landau parameter κ range. We can say that the spike state is originated by the expulsion of vortex-bubbles originated by deformation of a conventional giant-vortex, this process takes some nanoseconds, and occurs at a upper single field H_3. The spike state is analyzed solving the time-dependent-Ginzburg-Landau equations numerically en FC and ZFC processes. We show the extrusion process for several geometries and selected a κ for a genuine type-I superconductor, we believe that the sharp edges plays an important role in the formation and stability of the spike state because increasing the number of edges in the sample, will be easier the transition to the superconducting state.
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Topic: NM - New Materials
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AB INITIO STUDY OF THE CAPTURE OF LEAD USING THE T-MNO2 / GRAPHENE INTERFACE.
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ORTEGA LÓPEZ CÉSAR 1, DITA CASIANO JULIET VANESSA 2, SÁNCHEZ PACHECO LUIS 3,
1 Universidad De Córdoba , 2 Universidad de Córdoba, 3 Universidad de Córdoba,
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Email: luiscarlos@correo.unicordoba.edu.co
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Abstract: This work discusses the study of the adsorption of a lead atom on the surface of a T- MnO 2 /graphene interface. The calculations are based on the density functional theory (DFT) within the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) with ultrasoft pseudopotentials and a periodic slab scheme. A 1T-MnO 2 monolayer is coupled to a graphene monolayer with a mismatch below 3%. In this case, graphene is only used as a substrate for the 1T-MnO 2 monolayer. To satisfy the coupling conditions, the 1T-MnO 2 3x3 / graphene - 2√3 x2√3 structure is selected. The study of the most favorable adsorption model involves considering special sites TM1 (located just above an Mn atom, which is exactly above a C atom), TM2 (located just above an Mn atom, which is exactly above the center of the graphene hexagon), TO1 (located just above a C atom, belonging to the lower plane), and TO2 (located just above an O atom, belonging to the upper plane). The most favorable structure in terms of energy is the Cd-TO1 model, or ad-atom cadmium model, located in the TO1 site, with an adsorption energy of -4.0 eV. This adsorption site is also the most favorable in terms of energy for the adsorption of mercury and cadmium atoms over the T-MnO 2 /graphene heterostructure, with an adsorption energy of -0.4 eV [https://doi.org/10.1016/j.cocom.2022.e00704] and -0,6 eV, respectively. The value of the obtained adsorption energy is more negative than the ones reported for mercury and cadmium, hence the obtained absolute value is higher than the reported one (about 1.66 times higher than the mercury value and 10 times higher than the cadmium value). The calculations in this work are more favorable in terms of energy compared to the reported values. Nonetheless, both results lead to the conclusion that the TMnO 2 / graphene interface could be used as part of a device to capture heavy toxic metals such as mercury, cadmium, and lead. Lastly, the length of the lead-heterostructure bond is 1.66 Å, while the bond lengths for mercury and cadmium heterostructures are approximately 2.68 Å and 1.96 Å, respectively. The obtained adsorption energy and bond length lead to conclude that the results of this work are closer to chemical adsorption compared to the mercury and cadmium - heterostructure counterparts.
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Topic: NM - New Materials
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ADSORPTION OF MERCURY SPECIES ON THE T-MNO2 MONOLAYER: A FIRST-PRINCIPLES STUDY
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ORTEGA LÓPEZ CÉSAR 1, OSORIO GUILLEN JORGE M. 2, MORINSON NEGRETE JUAN DAVID 3,
1 Universidad De Córdoba , 2 Instituto de Física, Universidad de Antioquia, 3 Universidad de Córdoba ,
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Email: jdmorinson1984@hotmail.com
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Abstract: This research pertains to a study of the adsorption of mercury species 〖Hg〗^0, HgCl and 〖HgCl〗_2 on the surface of the 〖T-MnO〗_2 monolayer. The calculations are based on the density-functional theory (DFT) within the Perdew-Burke-Ernzerhof generalized gradient approximation (GGA-PBE) with the plane-wave pseudopotential method. The periodic slab scheme is used to model the 〖T-MnO〗_2 monolayer. The study of the most favorable adsorption model considers the special sites TM (located just above a Mn atom), TO1 (located just above an O atom in the lower plane) and 〖TO〗_2 (located just above an O atom in the upper plane). Regarding the adsorption of elemental mercury 〖Hg〗^0, it is concluded that the most favorable structure in terms of energy is the 〖Hg〗^0-〖TO〗_1 model, also known as the 〖Hg〗^0 ad-atom model located at the 〖TO〗_1 site with an adsorption energy of -0.36 eV. The most favorable models for HgCl and 〖HgCl〗_2 in terms of energy are the HgCl-TM ad-molecule (with Hg models facing downwards or closer to the surface than the Cl atom) and the 〖HgCl〗_2-TM (with the 〖HgCl〗_2 molecule parallel to the surface and the Hg atom located just above the TM site), with adsorption energies of 1.84 eV and -0.49 eV, respectively.
It is concluded that the 〖T-MnO〗_2 monolayer could serve as a component of a device that captures mercury species. Lastly, some dissociation scenarios are explored for HgCl and 〖HgCl〗_2.
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Topic: NM - New Materials
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A STUDY OF THE ELECTRONIC PROPERTIES OF THE G-ZNO/GRAPHENE INTERFACE WITH AND WITHOUT IMPURITIES DERIVED FROM CHROME, MANGANESE, AND COPPER.
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ESPITIA-RICO MIGUEL J. 1, ORTEGA LÓPEZ CÉSAR 2, BERRIO GUSTAVO 3,
1 Facultad de Ciencias Matemáticas y Naturales, Universidad Distrital Francisco José Caldas, 2 Universidad De Córdoba , 3 Universidad de Córdoba ,
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Email: gberrioc@gmail.com
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Abstract: This work discusses the study of the structural and electronic properties of the g-ZnO/graphene interface with and without substitutions of Zinc (Zn) atoms by chrome (Cr), manganese (Mn), and copper (Cu) atoms. The calculations are based on the density functional theory (DFT) within the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) with ultrasoft pseudopotentials and a plane wave basis. The interface is modeled using the periodic slab scheme. A g-ZnO monolayer is coupled to a graphene monolayer with a mismatch below 3%. To satisfy the coupling conditions, the g-ZnO 3x3 / graphene 4x4 reconstruction is selected.
For substitutions of Zn atoms at the interface, some Zn atoms located at special lattice points are chosen: Zn located at the origin of the coordinate system (point I), Zn located just above a point centered on the hexagon of the substrate graphene (point II) and Zn located just above a C atom (point III). The electronic properties of the g-ZnO/graphene interface with and without chromium, manganese and copper impurities are established through the density of states (DOS), band structure and Bader or Löwdin charge.
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Topic: NM - New Materials
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BIODEGRADABILITY OF CASSAVA STARCH-BASED BIOFILMS EXPOSED IN SIMULATED SOIL
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ARRIETA ALMARIO ALVARO 1, ACOSTA HUMÁNEZ MANUEL FERNANDO 2, DUCUARA JORGE 3,
1 Universidad de Sucre, 2 Universidad de Córdoba, 3 Universidad de Sucre,
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Email: jaducuarah@gmail.com
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Abstract: Biodegradability is a parameter that allows us to determine and measure the environmental behavior of chemical substances, to determine the properties of the products that are intended to be released into the natural environment. Studying the biodegradation of polymers based on renewable sources becomes important since these processes allow us to identify structural changes in the compound or imply its conversion into inorganic products of low molecular weight. In this aspect, biofilms based on starch were synthesized via a thermal method, using (1.0 g), GLY (1.0 g), PEG (1.0 g), and GLU (1.0 g) chemical compounds; starch biofilms were tested for biodegradability, using simulated soil prepared with 23% silty silt, 23% organic matter (cow excrement), 23% sand, and 31% distilled water, biofilm samples were exposed to the simulated soil and packed in sealed perforated bags. The bags were buried in the ground 10 cm deep. Biodegradation was monitored for 3 weeks, every 3 days mass variation was measured, buried samples were recovered, washed with distilled water, dried at room temperature, and weighed, after measuring the mass was analyzed by FTIR, and the samples were again buried. The experiments were conducted in triplicate. The biofilms from the third day began the loss of mass due to the decrease in moisture of the polymer, after 8-10 days the mass loss was 68%-75% concerning the initial mass, by the action of endoenzymes of the microorganisms present in the organic matter, in which break the bonds of the internal chain randomly, resulting in a rapid decrease in molecular mass, due to the sequential cleavage of the terminal segments, leading to immediate changes, forming smaller molecules such as monomers and oligomers. After 13 days, tiny samples were obtained, and the mass loss corresponded to 99% of the initial mass, finally, on days 15 and 16 were no traces of biopolymers. FTIR analyses showed the functional groups' intensity loss, due to biodegradation. Therefore, the biodegradability tests demonstrated that starch polymers are biodegradable in simulated soil, the biodegradation period was between 13-16 days, and organic matter plays a key role in the process thanks to the presence of microorganisms, which break bonds decreasing the molecular mass of polymers transforming them into monomers assimilable in the medium. Likewise, the authors acknowledge Ministerio de Ciencia, Tecnología e Innovación (Minciencias) for funding through project BPIN 2020000100027 with resources from the SGR (Sistema General de Regalías, Royalties General System). Moreover, the Universidad de Sucre is acknowledged for the financial support provided through the Call for Strengthening Research Groups of the Universidad de Sucre 2018-2019; approved by resolution No.16 of 2020 of the Academic Council.
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Topic: NM - New Materials
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BIODEGRADABLE POLYMER OF CASSAVA STARCH (MANIHOT ESCULENTA) AND CARDOL EXTRACTED FROM CASHEW NUTSHELL OIL
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ARRIETA ALMARIO ALVARO 1, ACOSTA HUMÁNEZ MANUEL FERNANDO 2, DUCUARA JORGE 3,
1 Universidad de Sucre, 2 Universidad de Córdoba, 3 Universidad de Sucre,
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Email: jaducuarah@gmail.com
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Abstract: Introduction: The main constituents of cashew nut shell oil (CNSL) are phenolic compounds with long-chain substitution at the meta position. These compounds give most of the reactions of phenol and can be the basis for producing a series of polymeric substances of utility in industrial applications. CNSL, which has a considerable cost-benefit ratio, can be a substitute for phenol in many applications. The use of CNSL instead of phenol is an excellent example of preserving a synthetically derived substance and using an economical agricultural product. Cardol is a relatively less explored component of CNSL that chemically offers resorcinol substituted with a 15-carbon chain and predominantly contains a mixture of one, two, and three double bonds. Methodology: Biofilms based on starch (1.0 g), GLY (1.0 g), PEG (1.0 g), and GLU (1.0), as well as cardol, were synthesized in different concentrations, and the biofilms were characterized by FTIR. The electrochemical properties were studied by cyclic voltammetry, with a potentiostat/galvanostat Gamry 1010E. Cyclic voltammetry was recorded at 10, 50, 100, 200, 400, 600, 800, and 1000 mV s-1 scanning speed. Biodegradability tests were performed using simulated soil prepared with 23% silty silt, 23% organic matter (cow feces), 23% sand and 31% distilled water. The experiments were developed in triplicate. Results and discussion: The biofilms composed of starch/cardol presented a brown color and better consistencies than those synthesized based on starch. The FTIR spectra of the biopolymer composite film revealed the presence of the OH group at 3600-3700 cm-1, this is present in cardol and starch. At 3000 cm-1 aromatic hydrogens (Ar-H) are shown, the bands at 2922- 2800 cm-1 are associated with the aliphatic C-H bond present in cardol, at 1608 cm-1 the C = C aliphatic bond is shown, and at 1452 cm-1 showed the presence of the C=C aromatic bond of the benzene ring. The oxidation-reduction processes peaks observed in the composite biopolymer films can be assigned to the redox processes of the starch and cardol glucose units present in the biopolymer matrix. Voltammetric sweep at different speeds showed a diffusion-controlled process, such that the electrochemical response depends on the movement of charges within the polymer matrix. The biodegradability test showed that the biofilms composed of starch/cardol degraded slower, this occurs due to the presence of phenolic compounds because they are assimilated by microorganisms and is an additional process in the degradation of the material. Conclusions: A new bioactive biopolymer compound, with a biological and biodegradable base, was synthesized from cassava starch and cardol extracted from cashew shell liquid. The effect of the amount of cardol and the pH of synthesis was studied. The study concluded that the biopolymer was stable to manual traction and the presence of cardol, as well as to the use of basic pH for its synthesis. Acknowledgments: The authors acknowledge Minciencias (Ministerio de Ciencia, Tecnología e Innovación, Ministry of Science, Technology, and Innovation) for funding through project BPIN 2020000100027 with resources from the SGR (Sistema General de Regalías, Royalties General System). Likewise, the University of Sucre is acknowledged for the financial support provided through the Call for Strengthening Research Groups of the University of Sucre 2018-2019; approved by resolution No.16 of 2020 of the Academic Council.
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Topic: NM - New Materials
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CAPTURE OF ARSENIC ON GRAPHENE-LIKE HEXAGONAL ZINC OXIDE MONOLAYER SURFACES WITH AND WITHOUT GRAPHENE SUBSTRATE
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ESPITIA-RICO MIGUEL J. 1, ORTEGA LÓPEZ CÉSAR 2, BERRIO GUSTAVO 3,
1 Facultad de Ciencias Matemáticas y Naturales, Universidad Distrital Francisco José Caldas, 2 Universidad De Córdoba , 3 Universidad de Córdoba ,
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Email: gberrioc@gmail.com
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Abstract: This study focuses on the adsorption of an arsenic atom on the graphene-like hexagonal zinc oxide monolayer with and without graphene substrate. The calculations are based on the density functional theory (DFT) within the Generalized Gradient Approximation of Perdew-Burke-Ernzerhof (GGA-PBE) with pseudo-potentials and a plane wave basis, as seen in the Quantum-Espresso package. The monolayer and interface are modeled using the supercell scheme, or periodic slab. Regarding the interface, a graphene-like hexagonal g-ZnO monolayer is coupled to a graphene monolayer with a mismatch below 3%. In this case, graphene is only used as a substrate for the ZnO monolayer. To meet the coupling conditions, the reconstruction g-ZnO 2x2 / graphene √7 x√7 is chosen. The study of the most favorable adsorption model in the monolayer involved considering special sites H (located at the center of an hexagon of the g-ZnO monolayer), TO (located just above an O atom and without a C atom underneath), TZn (located just above a Zn atom and without a C atom underneath), TO-C (located just above an O atom and having a C atom underneath), and TZn-C (located just above a Zn atom and having a C atom underneath). Regarding the monolayer, it is determined that the most energetically favorable structure is the As-H model, or arsenic ad-atom model, located in the H site, with an adsorption energy of -1.84520 eV. Regarding the interface, the most favorable structure is the As-To model, or arsenic ad-atom model, located in the To site, with an adsorption energy of 2.29936 eV. It is concluded that the graphene substrate is useful for capturing heavy and toxic arsenic atoms.
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Topic: NM - New Materials
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CAPTURE OF CADMIUM USING THE T-MNO2 / GRAPHENE INTERFACE
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DITA CASIANO JULIET VANESSA 1, ORTEGA LÓPEZ CÉSAR 2, MORINSON NEGRETE JUAN DAVID 3,
1 Universidad de Córdoba, 2 Universidad De Córdoba , 3 Universidad de Córdoba,
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Email: juanmorinson@correo.unicordoba.edu.co
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Abstract: This work discusses the study of the adsorption of a cadmium atom on the theory (DFT) within the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) with ultrasoft pseudopotentials and a basis of plane waves. The interface is modeled using the periodic slab scheme. A T-MnO2 monolayer is coupled to a graphene monolayer with a mismatch below 3%. In this case, graphene is only used as a substrate for the T-MnO2 monolayer. To satisfy the coupling conditions, the T-MnO2-3x3/graphene - 2√3 x2√3 reconstruction is chosen. The study of the most convenient adsorption model involved considering special sites TM1 (located just above a Mn atom, which is exactly above a C atom), TM2 (located just above a Mn atom, which is exactly above the center of the graphene hexagon), TO1 (located just above an O atom, belonging to the lower plane), and TO2 (located just above an O atom, belonging to the upper plane).
The most favorable structure in terms of energy corresponds to the Cd-TO1 model or the ad-atom cadmium model located in the TO1 site, with an adsorption energy of -0.6 eV. This adsorption site is also the most energetically favorable for the adsorption of a mercury atom on the T-MnO2/graphene heterostructure, with an adsorption energy of -0.4 eV. [https://doi.org/10.1016/j.cocom.2022.e00704].
The obtained adsorption energy has a more negative value than the one stated for mercury, yet the obtained absolute value is higher than the one stated for mercury (about 1.66 times higher), which makes the results of this paper more optimal in terms of energy. However, both results reveal that the T-MnO2 / graphene interface could be used as part of a device to capture heavy toxic metals such as mercury and cadmium.
Lastly, the length of the cadmium - heterostructure bond is approximately 1.96 Å, while the length of the mercury - heterostructure bond is approximately 2.68 Å. The obtained adsorption energy and bond length lead to conclude that the results of this work are closer to a chemical adsorption compared to the mercury - heterostructure counterpart.
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Topic: NM - New Materials
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CHARACTERIZATION OF STRUCTURAL PROPIERTIES AND OF THE SURFACE ON THE ELECTRONICS OF TITANIUM DIOXIDES WITH CERIUM IMPURITY.
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CASIANO JIMÉNEZ GLADYS ROCÍO 1, ALCALÁ VARILLA LUIS ARTURO 2, PÁJARO POLO LORENA 3,
1 Universidad de Córdoba, 2 Universidad de Córdoba - Colombia, 3 Universidad de Córdoba,
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Email: lpajaropolo@correo.unicordoba.edu.co
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Abstract: In the present work, the structural and electronic properties of titanium dioxide (TiO2) surfaces are established, with the addition of cerium (Ce) impurities. For this, first principles simulations are carried out within the framework of the density functional theory (DFT) applying the pseudopotential method, implemented in the Quantum ESPRESSO computational package. For the electron–electron interaction, the Generalized Gradient Approximation (GGA) is used in the Perdew-Burke-Ernzerhof (PBE) parameterization and, in addition, the Hubbard (U) correction for atoms was taken into account titanium. Initially, the structural parameters were optimized; in this instance, the ground state energy of the clean surface and the doped surface are determined. From calculations of the density of states (DOS), it is inferred that the clean surface presents a semiconductor character, while, by introducing a cerium atom on the surface of the titanium dioxide, this reduces the energy band, providing better use of the visible spectrum. The Ce impurity on the TiO2 surface could favor a greater photocatalytic activity in the degradation of contaminants and increase the oxidative capacity of titanium dioxide.
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Topic: NM - New Materials
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CYCLIC USE OF A PUMICE-BASED GEOPOLYMER FOR THE REMOVAL OF CADMIUM PRESENT IN INDUSTRIAL EFFLUENTS
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MONTAÑO ANGARITA ANGELA MARCELA 1, GONZALEZ CUERVO CLAUDIA PAULINA 2, RUEDA DUARTE LISI MILDRED 3, GUTIERREZ GALLEGO JOSE CARLOS 4,
1 Universidad Industrial de Santander, 2 Universidad Pontifica Bolivariana, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander,
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Email: jcgutier@uis.edu.co
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Abstract: The increase in population, urbanization, technological advances and industrial production, have generated continuous degradation of the environment derived from discharges and production of waste and by-products, such as tanneries, electroplating, metal finishes, among other; releasing wastewater with heavy metals into natural sources. These pollutants are harmful to living beings due to their persistence, prevalence, and toxicity. Consequently, new materials called geopolymers have been used, which act as adsorbents due to their high efficiency in the removal of contaminants and easy synthesis, however, the possibility of reusing them to extend their useful life has not been widely studied, Because of that, various technologies have been implemented to regenerate the material and thus reuse it, such as thermal and chemical treatment, through the use of acids and high temperatures. In the present work, the cyclical use of a pumice-based geopolymeric material was evaluated, which was previously contaminated with a cadmium sulfate solution and subsequently subjected to chemical treatment with a hydrochloric acid solution to eliminate the heavy metal present. The geopolymer was synthesized following the methodology defined in previous works by the authors, after this, it was characterized by X-ray diffraction, to see the change in the structure of the precursor with respect to the synthesized material, verifying the formation of silicate networks; scanning electron microscopy where the difference in morphology between the pumice stone and the geopolymer was observed, finding for the first characteristic homogeneous surfaces and for the geopolymer agglomerates with heterogeneous surfaces. For the sorption tests, the dose of geopolymer used was 0.2 grams in contact with 25 mL of 2 ppm cadmium sulfate solution for 3 hours. For the desorption stage, 0.05 grams of contaminated geopolymer were used in contact with 25 mL of a 0.05 M solution of hydrochloric acid for 2 hours. Finally, the sorption and desorption percentages were determined in the aqueous phase using the atomic absorption technique, these measurements showed that the material presents up to four cyclical uses, maintaining adsorption percentages between 90% and 97% and desorption between 70% and 85%. demonstrating that the material is suitable for adsorption-desorption processes of pollutants present in water.
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Topic: NM - New Materials
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DIOXIDES TRANSITION METAL MONOLAYERS: AB INITIO STUDY
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ESPITIA-RICO MIGUEL J. 1, ORTEGA LÓPEZ CÉSAR 2, HUMANEZ TOBAR ÁNGEL 3,
1 Facultad de Ciencias Matemáticas y Naturales, Universidad Distrital Francisco José Caldas, 2 Universidad De Córdoba , 3 Universidad de Córdoba ,
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Email: angelhumaneztobar@gmail.com
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Abstract: In this work, we present the results based on density functional theory study of the two-dimensional ternary alloys of transition-metal dioxides TMxV1-xO2 (TM=Cr, Mo and W for x = 0.0, 0.25, 0.50, 0.75, 1.0) in the hexagonal structure 1H. The structural and electronic properties as well as energy stability were calculated with Quantum ESPRESSO computational code using the Generalized Gradient Approximation with Perdew−Burke−Ernzerhof formulation. For x = 0 and x = 1 it was found that the lattice constants values and formations energies of VO2, CrO2, MoO2 and WO2 monolayers are in excellent agreement with the values reported by other authors, which guarantees the reliability of our calculations. It was found that the formations energies of all two-dimensional ternary alloys are negative, therefore the monolayers are stable energetically. In additionally, band structures and density of states studies show that Cr0.25V0.75O2 monolayer has a half-metallic behavior with a magnetic moment of 1.00 µB/cell. while the Mo0.25V0.75O2 and W0.25V0.75O2 monolayers exhibit a metallic behavior with magnetic moments of 0.40 µB/cell and 1.06 µB/cell, respectively. The Cr0.50V0.50O2, Cr0.75V0.25O2, Mo0.50V0.50O2, Mo0.75V0.25O2, W0.50V0.50O2 and W0.75V0.25O2 has a metallic character with no magnetic properties. These two-dimensional ternary alloys of transition-metal dioxides are candidates for applications in different technological fields, for example in spintronic and spin injector.
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Topic: NM - New Materials
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EFFECT OF MINOR ADDITION OF MARBLE DUST ON THE COMPRESSIVE STRENGTH OF CONCRETE COMPOSITES
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GARCIA NEGRETE CARLOS 1, BELTRÁN GUZMÁN DANIELA 2, PEÑATE VÁSQUEZ LUISA 3, LÓPEZ FIGUEROA JESÚS 4, MONTIEL CARDOZO WILLIAM 5, PARRA-JIMENEZ KORLLVARY 6,
1 Universidad del Sinú, 2 Universidad del Sinú, 3 Universidad del Sinú, 4 Universidad del Sinú, 5 Universidad del Sinú, 6 UNIVERSIDAD DEL SINU - ELIAS BECHARA ZAINUM,
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Email: korllvaryparra@unisinu.edu.co
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Abstract: Marble dust, a material with a content rich in CaCO3, use to be produced during the processing of naturally available marble worldwide. Thus, large amount of marble dust becomes waste in many factories around the world. If this waste is discarded and accumulated, there is a potential risk of contamination for the environment. Therefore, the search for applications for waste marble dust (WMD) is of great interest. In this work, the WMD sample was collected from a factory located in the city of Montería (Colombia) and then tested as additive in the preparation of concrete composites. An economic concrete design was proposed, with a strength of 3000 PSI, that is for general use. Once the results of the mix design were obtained, these were taken as the basis for the preparation of concrete composites with 0 %, 3 %, 7 % and 10 % of WMD respect to cement content. The samples prepared were tested in compression after varied curing times. It was found that the compressive strength of composites with both 3 % and 7 % of WMD was better than the corresponding one for the sample without WMD addition. This improvement in the compressive strength was consistently observed after both 14 and 28 days of curing. After 14 days of curing, the compressive strength increased slightly from 23.08 (± 1.34) Mpa to 25.36 (± 0.11) Mpa and 25.59 (± 0.24) for composites with 3 % and 7 % of WMD respectively. Similarly, after 28 of curing, the compressive strengths were 25.76 (± 0.47) Mpa, 28.89 (± 1.40) Mpa and 27.70 (± 0.18) Mpa for samples with 0 %, 3 % and 7 % of WMD respectively. However, the increases in the WMD content from 0 % to 10 % did not produced an improvement in the compressive strength, showing that there is a limit for the beneficial addition of WMD in the concrete composites. It can be concluded that the minor addition of WDM (3 % and 7 %) in concrete composites represents an application with the potential for reducing the accumulation of waste in marble factories.
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Topic: NM - New Materials
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EFFECT OF THE FE3+ ION SUBSTITUTION IN THE B-SITE ON ELECTRIC AND MAGNETIC PROPERTIES OF THE NOVEL PEROVSKITE SR0.33SM0.67TI0.33MN0.67O3 CERAMICS
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ROA-ROJAS JAIRO 1, SAAVEDRA GAONA INDRY MILENA 2, PARRA VARGAS CARLOS ARTURO 3, CUERVO FARFÁN JAVIER ALONSO 4, CUBILLOS CADENA JOSE MAURICIO 5,
1 Universidad Nacional de Colombia - Bogotá, 2 Grupo Física de Materiales, 3 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 4 Universidad Pedagógica y tecnológica de Colombia-Tunja, 5 GISABA, Escuela de Ingeniería Ambiental, Facultad de Ingeniería, Universidad Pedagógica y Tecnológica de Colombia,
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Email: jose.cubillos@uptc.edu.co
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Abstract: Partial substitution of 39% in B-site cationic with Fe3+ ions in the new perovskite-type Sr0.33Sm0.67Ti0.33Mn0.67O3 ceramic synthesized by the conventional solid-state reaction method, increased the sintering temperature and the unit cell volume of its orthorhombic structure (space group Pnma # 62) by 0.4%. This induced a reduction in grain size and electrical transport according to V-I measurements, where semiconductivity behavior was evidenced, with resistivity values in the linear regime for the ceramic without substitution of 51.72 ohm·cm and after the substitution of 26912.93 ohm·cm, finding variations in the thermistor-type behavior of the material. In addition, as observed in the magnetization curves as a function of the applied field and susceptibility as a function of temperature, caused a change from ferromagnetic to ferrimagnetic order with temperatures of Tc=81.32 K and Tc= 65.32 K, respectively.
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Topic: NM - New Materials
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EFFECTS OF THE SUBSTITUTION OF TRANSITION METAL ATOMS ON THE ELECTRONIC PROPERTIES OF G-ZNO MONOLAYER.
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BERRIO GUSTAVO 1, OSORIO GUILLEN JORGE M. 2, ORTEGA LÓPEZ CÉSAR 3,
1 Universidad de Córdoba , 2 Instituto de Física, Universidad de Antioquia, 3 Universidad De Córdoba ,
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Email: cesarorlo@gmail.com
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Abstract: This work describes the study of the structural and electronic properties of a g-ZnO monolayer with and without substitution of zinc (Zn) atoms by chrome (Cr) and manganese (Mn) atoms. The calculations are based on the density functional theory (DFT) within the Generalized Gradient Approximation of Perdew-Burke-Ernzerhof (GGA-PBE) and GGA+U, along with ultrasoft pseudopotentials and a basis of plane waves. The interface is modeled using the periodic slab scheme. In this case, a graphene-like hexagonal zinc oxide monolayer (g-ZnO-4x4) is used. The monolayer contains an empty region of 20 Å, to guarantee the periodicity of the system. The thermodynamical stability of the g-ZnO-4x4 monolayer with and without impurities is determined through the formation energy.
To determine the electronic properties, the density of states (DOS), bands, and Bader or Löwdin charges are computed. The results for DOS and band structures reveal that the pristine monolayers are semiconductors and non-magnetic, while the monolayers with chrome impurities are metallic and those with manganese impurities are semi-metallic. The impurities of chrome atoms give a ferromagnetic nature to the monolayer, while the manganese impurities give a ferromagnetic or anti-ferromagnetic nature, depending on the monolayer configuration.
Lastly, the Bader or Löwdin charges are calculated for the g-ZnO-4x4 monolayer with and without chrome and manganese impurities for the purpose of establishing the charge transfer.
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Topic: NM - New Materials
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ELECTRIC-FIELD DIPOLE ENGINEERING AT THE NANOSCALE
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TIDROW STEVEN 1,
1 Alfred University,
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Email: tidrow@alfred.edu
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Abstract: Efficient energy conversion and high energy density storage materials that support high power rates and trillions of cycles, made of environmentally friendly materials, are needed to overcome environmental sustainability issues. The construct of electric-field dipole engineering at the nanoscale (E-DENS) affords special opportunity for material science and engineering not contemplated within semiconductor physics. E-DENS provides the opportunity for scientific investigation of local through macroscale electric-fields and an engineering opportunity to systematically control essential intrinsic material properties: resistivity, breakdown field strength, relative permittivity and loss tangent that control the efficiency of energy conversion, length of time and amount of energy density that can be stored. Semiconductor physics can be modified to understand the results of E-DENS, local reverse biased p-n junction effects at the nanoscale that increase resistivity and breakdown field strength, which control the length of time dielectric energy can be stored and the maximum energy that can be stored for a given relative permittivity material. The relative permittivity can be designed using the Mossotti – Lorenz – Lorentz – Clausius relation. The resistivity and electric-field breakdown strength of the material can be designed using appropriate dipole pairs. Data are presented that demonstrate the unique potential of E-DENS as both a scientific and engineering tool. Currently, at low concentration of substituents (<2 at%), resistivity has been shown to increase resistivity by up to ten-million times, breakdown field strength by more than an order of magnitude, and diffuseness of relative permittivity controlled from ferroelectric to diffuse phase transition to relaxor-like properties; yet, the materials are not strict relaxors.
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Topic: NM - New Materials
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ELECTRONIC AND MAGNETIC PROPERTIES OF W-BN DOPED WITH V
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CASIANO JIMÉNEZ GLADYS ROCÍO 1, DÍAZ-FORERO JONH H. 2, ESPITIA-RICO MIGUEL J. 3,
1 Universidad de Córdoba, 2 Facultad de Ciencias Matemáticas y Naturales, Universidad Distrital Francisco José de Caldas, 3 Facultad de Ciencias Matemáticas y Naturales, Universidad Distrital Francisco José Caldas,
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Email: mespitiar@udistrital.edu.co
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Abstract: We present the results of first-principles calculations carried out to investigate the structural properties and electronic structure of BN in the wurtzite structure doped with V atoms and with 6.25% and 12.5% concentrations. The calculation were performed using the pseudopotential method and the generalized gradient approximation (GGA) in framework of the density functional theory such as implemented in the Quantum ESPRESSO computational package.
The calculated lattice parameters of w-BN are in good agreement with previous theoretical results. The analyze of band structure and the density of states reveals that B_0.9375 V_0.0625 N and B_0.875 V_0.125 N compounds have a half-metallic-ferromagnetic behavior being the spins up states metallic and spins states down semiconducting. We found the magnetic moment of 2.0 μ_β µ and 4.0 μ_β per cell, respectively. These magnetic properties come from of the hybridization of V-3d, B-2p and N-2p.
These magnetic properties indicate that V-doped w-BN compound can potentially be used in diluted magnetic semiconductors or as spin injectors.
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Topic: NM - New Materials
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ENERGETICS IN THE GROWTH OF A GRAPHENE-LIKE HEXAGONAL ZINC OXIDE MONOLAYER ON GRAPHENE SUBSTRATE
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BERRIO GUSTAVO 1, PENICHE-BLANQUICETT FRANKLIN 2, ORTEGA LÓPEZ CÉSAR 3,
1 Universidad de Córdoba , 2 Grupo Avanzado de Materiales y Sistemas Complejos GAMASCO, Universidad de Córdoba, 3 Universidad De Córdoba ,
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Email: cesarorlo@gmail.com
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Abstract: It is hard to determine the energetics involved in the interfaces of bidimensional materials only through experimental research. Fortunately, theoretical calculations can be used to study and assess thermodynamical stability, structural stability of stacking patterns, interfacial bond strength and stability of interfacial geometry using energy formation, binding energy, adhesion work and interfacial energy, respectively.
This work discusses the study of energetics involved in the growth of a graphene-like hexagonal zinc oxide monolayer on graphene substrate (g-ZnO / graphene). The calculations are based on density functional theory (DFT) within the Generalized Gradient Approximation of Perdew-Burke-Ernzerhof (GGA-PBE) along with ultrasoft pseudopotentials and a plane wave basis as seen in the Quantum-ESPRESSO package. The interface is modeled using the supercell scheme or periodic slab. A g-ZnO monolayer is coupled to a graphene monolayer with a mismatch below 3%. In this case, the graphene is only used as a substrate for the ZnO monolayer. To meet the coupling condition, the reconstructions g-ZnO 2x2 / graphene √7 x√7 y g-ZnO 3x3 / graphene 4x4 are chosen.
The formation energy values, binding energy, adhesion energy, and interfacial energy are computed for both reconstructions of the g-ZnO/graphene interface, finding that both reconstructions are energetic and thermodynamically stable. Hence, graphene is a proper substrate for the g-ZnO monolayer.
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Topic: NM - New Materials
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EVALUATION OF THE EFFECT OF A THERMOSETTING COATING OF POLYURETHANE RESIN AND GRAPHENE OXIDE ON PHYSICOCHEMICAL AND MECHANICAL PROPERTIES OF CEMENTITIOUS MATRICES
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DÍAZ RAMÍREZ GERMAN A. 1, MEJÍA OSPINO ENRIQUE 2, GUTIÉRREZ NIÑO NELSON 3, SAAVEDRA SAENZ JUAN MANUEL 4, CRUZ RICARDO 5, FORERO CASTRO DIANA PATRICIA 6, BALLESTEROS RUEDA LUZ MARINA 7,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Industrial University of Santander, 5 Universidad Industrial de Santander, 6 Universidad Industrial de Santander, 7 universidad Industrial de Santander,
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Email: luzmabal@uis.edu.co
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Abstract: Concrete structures are structural elements made of cement, aggregates (sand, gravel, crushed stone), and admixtures. Among the best-known are reinforced concrete structures, which contain steel bars as reinforcement. As a consequence of the agents to which the structures are exposed, corrosion is generated in the concrete bars, which over time, causes fissures and cracks. The prevention of these signs of deterioration can be addressed through coatings, which according to their nature, provide new properties or improve the existing ones. The present research aims to evaluate the effect of a polyurethane resin and graphene oxide (PUOG) coating on a cementitious matrix's physicochemical and mechanical properties. The methodology used comprised two phases: the first consisted of establishing a protocol for applying the resin on the cementitious matrix by comparing three application methods. In the second stage, the influence of the coating on the interfacial adhesion and permeability properties of the matrix was estimated by means of sessile drop, pull-off, and degradation tests (by immersion in aggressive environments). The evaluation of each test was performed on cylindrical concrete coupons of 5.08 cm in diameter and 3.81 cm high, which were manually coated. This procedure was performed by depositing different amounts of coating as layers using a fully coated sponge. The contact angle tests for the coated concrete element showed that the use of PUOG resin gives a hydrophobic character to the system after 3 layers of coating, as for the measurements taken for the systems with two layers, a significant change was evidenced with respect to the system without layers, this last mentioned system absorbs the water drop in greater quantity and in less time, that is why the angle from which the drop falls is variable. The mechanical failure (obtained by pull-off tests) showed that the system initiates its breaking point or detachment inside the concrete coupon and not at the resin/concrete interface, which evidences the adhesion potential of the coating. The concrete/resin system was subjected to acidic environments to observe its effect on the deterioration time in which it was observed that the amount of material that detaches from the uncoated system when in contact with an acid solution for 30min and 1h is significant approximately 11 gr, the opposite case happens with the 2 and 3 layer systems, these two loose weight, although they do not exceed 4 gr per system. The applicability of polyurethane resin and graphene oxide on cementitious structures shows they have great potential to improve cementitious structures' chemical and mechanical properties.
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Topic: NM - New Materials
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EXPERIMENTAL DETERMINATION OF THE EFFECTIVE THERMAL CONDUCTIVITY WITH DIRECT TEMPERATURE MEASUREMENT TECHNIQUE FOR BP6 K
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AVELLA RICHARD 1, FERNANDEZ ALEJANDRA MARIA 2, MESTRA JUAN CARLOS 3,
1 fundación universitaria los libertadores, 2 Fundación Universitaria los libertadores, 3 Fundacion universitaria los libertadores,
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Email: jcmestrao@libertadores.edu.co
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Abstract: In this study, we experimentally determined the thermal conductivity for different BPGK 10 films, doped with different percentages of clay using the direct temperature measurement technique. We found that the thermal delay time is a function of the power supplied to the samples. It was also found that increasing the percentage of clay increases the thermal conductivity of the films, causing a decrease in thermal resistance and therefore an increase in heat flow through the sample. Finally, the results obtained from this characterization indicate that BPGK 10 films can find applications as coatings in heat exchangers, electronic and aerospace components.
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Topic: NM - New Materials
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INFLUENCE OF THE SYNTHESIS PATHWAY UPON THE THERMOLUMINESCENT RESPONSE OF GADOLINIUM ALUMINATE MATRIX PHOSPHORS
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ZARATE-MEDINA JUAN 1, ALONSO SOTOLONGO ALEJANDRO 2, RIVERA MONTALVO TEODORO 3,
1 UNIVERSIDAD MICHOACAN DE SAN NICOLAS DE HIDALGO, 2 Universidad Michoacana de San Nicolas de Hidalgo, 3 Instituto Politécnico Nacional, CICATA-Legaria,
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Email: riveramt@hotmail.com
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Abstract: The phosphors that present of a glow curve with a peak much more intense than the others, a sensitization to low doses and a linear relationship between the thermoluminescent response and the dose, are demanded in the dosimetry market. The gadolinium aluminate has been successfully used as host of phosphors with luminescent properties. Principally, the luminescent response of the said matrix has been improved by doping with rare earths ions. The thermoluminescent signal depends on the synthesis route, since the crystal defect density is closely connected to the pathway that the material went through to be produced. Thus, as part of the optimization process to sensitize a phosphor, it is necessary to choose the synthesis route that enhances the efficiency of its thermoluminescent mechanisms. The research herein was focused on synthetizing phosphors with stoichiometries GdAlO3 and Gd0.98Dy0.02AlO3 by three routes and determine the most recommendable to improve their thermoluminescent response. The synthesis methods were the reverse coprecipitation, where was changed the source of the Al3+ ions to determine how influential the raw material was, and the third was modified citrate precursor method. The phosphors yielded by reverse coprecipitation method showed the most sensitive thermoluminescent signals, mainly, the Dy3+ ion activated phosphor produced the most intense signal that could be related to the most suitable density and distribution of crystal defects.
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Topic: NM - New Materials
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LOW COST GEOPOLYMERS PREPARED FROM PUMICE STONE AND THE INFLUENCE OF THE ALKALINE ACTIVATOR IN THE SORPTION OF METHYLENE BLUE
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BARÓN GUALDRÓN GISELLE CAROLINA 1, MONTAÑO ANGARITA ANGELA MARCELA 2, GONZALEZ CUERVO CLAUDIA PAULINA 3, JEREZ SANTAMARIA DANIELA ALEXANDRA 4, GUTIERREZ GALLEGO JOSE CARLOS 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Pontifica Bolivariana, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Santander,
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Email: jcgutier@uis.edu.co
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Abstract: The need to find new sorbent materials that are sustainable, efficient and economically viable has drawn the attention of researchers towards geopolymers. Particularly, there is a great interest in finding precursors that provide better properties to the product and likewise, establish the most convenient synthesis parameters for their application as sorbents. Therefore, in this investigation the removal efficiency of methylene blue (AM) from synthetic aqueous solutions was determined using synthesized geopolymers based on pumice stone (PP) substituted with 10 and 15% alumina, conditions established from the results. of XRF of the PP. Alkaline activator solutions composed of sodium silicate and sodium hydroxide in a range of concentrations were used and from the AM removal tests the materials with the best performance in the removal process were determined, these being the ones synthesized with 9M concentration. These materials and their precursor were characterized by XRD, SEM-EDS, and FTIR and physisorption analysis. From XRD, the appearance of new crystalline phases and the increase of some amorphous areas after the geopolymerization process were observed. In turn, using SEM-EDS, morphological differences were established between the precursor, which presented a smooth surface, and the geopolymers, in which rough surfaces appeared, which were associated with the incorporation of aluminum in the three-dimensional structure formed, which also it was observed by changes in the bands of the FTIR spectra. Physisorption analyzes revealed the mesoporous structure of the material. Finally, the best conditions of the removal process corresponding to a pH of 10 of the AM solution, 0.2 g sorbent dose, 15 ppm initial sorbate concentration and 3h contact time were established; observing a great influence of electrostatic interactions and phenomena such as material saturation in the removal process. The isotherms exhibited the presence of physisorption phenomena, although the kinetic models suggested that chemisorption limited the rate of the process. The results obtained show the usefulness of the material in the removal of methylene blue with removal efficiencies of up to 89.2%.
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Topic: NM - New Materials
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MAGNETIC MICROSPHERES OBTAINED FROM RAW IRON ROLLING SCALE
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RIVERA FIGUEROA EDISON 1, MUÑOZ-MENESES RODRIGO ARBEY 2, MARIN-MERCADO LORENA 3, TABARES GIRALDO JESÚS A. 4, DIOSA JESÚS E. 5, MOSQUERA-VARGAS EDGAR 6,
1 Grupo de Transiciones de Fase y Materiales Funcionales (GTFMF), Universidad del Valle - Grupo Producción e Innovación (Pi), Fundación Universitaria de Popayán, 2 Facultad GAMA, Universidad de Brasília, 3 Grupo de Películas Delgadas (GPD), Centro de Excelencia en Nuevos Materiales (CENM), Departamento de Física, Universidad del Valle, 4 Grupo de Metalúrgica Física y Teoría de Transiciones de Fase (GMTF), Centro de Excelencia en Nuevos Materiales (CENM), Departamento de Física,Universidad del Valle, 5 Grupo de Transiciones de Fase y Materiales Funcionales (GTFMF), Centro de Excelencia en Nuevos Materiales (CENM), Departamento de Física, Universidad del Valle, 6 Grupo de Transiciones de Fase y Materiales Funcionales (GTFMF), Centro de Excelencia en Nuevos Materiales (CENM), Departamento de Física, Universidad del Valle,
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Email: edgar.mosquera@correounivalle.edu.co
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Abstract: Mill scale (calamine) is a layer of oxides that forms on the surface of steel during the hot-rolled process. In addition to metal oxides and water, they usually contain other impurities such as industrial greases and oils. On average, between 35 and 40 kg of calamine are produced for every ton of rolled steel. Despite being a very interesting industrial by-product due to its high concentration of iron (~72% by weight), its reuse in new production processes is low, with most of the calamine ending up in landfills, posing a serious environmental risk due to the leaching of heavy metals into the soil.
In this research, samples of mill scale provided by two Colombian steel companies were used, one of them contaminated with greases and oils, which required pre-treatment with organic solvents for cleaning. Subsequently, the materials were pulverized in a low-energy ball milling, sieved, and fluidized in a flame reactor from the propane/oxygen combustion. The obtained microparticles (with sizes between 10 – 90 µm) and the precursor material were characterized by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Mössbauer spectroscopy (MS), and scanning electron microscopy (SEM). From the XRD and MS analysis, the wustite, hematite, and magnetite phases were determined from the precursor material. After flame fluidization, XRD, MS, and SEM showed that the starting acicular particles transform into microspheres, being the magnetite phase as the majority crystalline phase. FTIR measurements corroborates the presence of metal-oxide bonds associated with iron oxides. SQUID measurements were performed to determine the magnetic properties of the samples. SQUID showed that the saturation magnetization and coercivity were between 84–94 emu/g and 22–23 Oe, respectively. Thus, this work presents an alternative for the recovery of this by-product, being attractive in different industrial environments, in a fast and economic route.
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Topic: NM - New Materials
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NANOSTRUCTURES AND NANOCOMPOSITES OF POLYMERIC MATRIX FOR WASTE REUSE AND ENVIRONMENTAL REMEDIATION
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PARIS ELAINE CRISTINA 1,
1 Embrapa,
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Email: elaine.paris@embrapa.br
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Abstract: Nanomaterials have been applied in various areas of society. There is a growing demand for developing systems with superior performance and lower costs. Materials obtained from the recovery of mineral and agricultural waste have been gaining more space due to the environmental impact minimization and the obtaining of second-generation products. In both cases, it is possible to perform reuse, separation and obtaining new compounds with active properties from an appropriate chemical treatment associated with different processing. In turn, synthetic nanomaterials obtained by commercial sources require precursor sources that allow structural and morphological control, and reproducibility, resulting in a wide range of research to obtain more efficient technologies and reduced cost. Recoverable and reusable nanomaterials for water and air decontaminating by adsorptive and photocatalytic processes, which have a high surface area, are promising for environmental remediation. Furthermore, nanostructures can be inserted into polymeric systems, allowing their use as nanocomposite films and fibers with unique properties that favor easy recovery in application processes and their use in antimicrobial and ultraviolet-visible protection membranes, mechanical reinforcement, and in the release of agro-industrial nutrients. Nanoparticles can be used to deliver mineral nutrients to the soil. The effectiveness of the process may be associated with conditioning methods of these nanoparticles in biodegradable polymers to adjust the nutrient delivered. The development of films for sustainable packaging, optical protectors, or bactericides can be obtained through components from natural and biodegradable and/or waste sources to obtain nanostructures that favor reinforcement conditions for these nanocomposites, resulting in resistant products with added value. Thus, the present work seeks to elucidate ways to obtain and apply nanocomposites that improve their properties by adding synthetic or waste treatment nanostructures. Therefore, understanding the possibilities of reusing waste enables a gain with inestimable value since it makes it favorable to obtain environmentally friendly materials as an alternative to the circular economy.
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Topic: NM - New Materials
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NEXT GENERATION MATERIALS FOR ELECTRONIC APPLICATIONS
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FERNANDEZ ZAPICO GUILLERMO 1,
1 Triboblend,
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Email: guillermo.fernandez.zapico@gmail.com
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Abstract: Recently, the quantity of data generated has increased exponentially creating the necessity of more efficiency and fast data treatment.
The Moore law indicates that the number of transistors on the chip is duplicated every two years, which allows faster computing performance (current transistor are as small as 2nm).
However, in the last years, it seems that the Moore law is “dying”, creating the necessity of investigating new alternatives which allow better and faster performance without decreasing the transistor size. Among this alternatives, we can find advanced materials.
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Topic: NM - New Materials
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OPTIMIZATION OF THE BIOCHAR GENERATION PROCESS FROM COCONUT ENDOCARP (COCUS NUCIFERA) AS A POTENTIAL SOURCE FOR THE SYNTHESIS OF GRAPHENE MATERIALS
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ARRIETA ALMARIO ALVARO 1, VEGA VEGA YAIR ALFONSO 2, VANEGAS VITOLA CARLOS FERNANDO 3,
1 Universidad de Sucre, 2 Universidad de Sucre, 3 Universidad de Sucre,
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Email: carlos.vanegas@unisucrevirtual.edu.co
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Abstract: In this study, an optimization of the biochar generation process was carried out by standardizing the predictor variables of temperature and heating time of the coconut endocarp for the extraction of vegetable graphite, seeking to maximize the performance and quality parameters. Coconut shells were collected to be crushed until fragments of approximately 1 cm were obtained, then samples of approximately 40 g were taken. that underwent heating in an oven at different temperatures (300, 400, 600, 800 and 1000 °C) and times (3, 5, 7, and 10 h). All trials had a warm-up time of 30 min. Then, each sample was weighed to calculate the yield percentage (%R) of the obtained graphite. Now, the samples that presented a %R equal or greater than 50 % were macerated and sieved in a 160 µm sieve, in order to apply Fourier transform infrared (FTIR) and Raman spectroscopy for their respective characterization. Finally, a response surface analysis and its optimization were applied to the results, using the Minitab v.19.1 software. The obtained carbon was used to synthesize graphene oxide by controlled calcination. Results and discussion: The results indicate that at temperatures less than or equal to 300 °C, some components of the coconut endocarp such as lignin, cellulose and hemicellulose, calcination was incomplete. At temperatures above 300 °C, if such a process could be evidenced. However, the analysis of the response surface showed that both temperature and time have a certain influence on the quality and performance parameters, since these variables decrease the organization degree between the bonds of the carbon atoms present in the material vegetable graphite obtained. The obtained product was used for the synthesis of graphene oxide, which was characterized by FTIR and Raman spectroscopy. From IR spectroscopy, the presence of functional groups associated with graphene oxide is evidenced, likewise, the Raman spectrum showed the characteristic peaks of said product. Conclusion: The variables temperature and time delay resulting in theyield and quality for synthesis of vegetable graphite based on agro-industrial residues fromcoconut endocarp. Furthermore, response surface analysis reveals that the optimal temperature and time to extract this material is 632 °C and 3 h, respectively. Finally, the obtained graphite was able to synthesize graphene oxide through a second calcination. Acknowledgments: The authors acknowledge Minciencias (Ministry of Science, Technology and Innovation) for financing the project BPIN 2021000100052 with resources from the SGR - General Royalty System, the University of Cordoba and the University of Sucre for financial support provided through the Call for Strengthening Research Groups of the University of Sucre 2018-2019; approved by resolution No.16 of 2020 of the Academic Council.
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Topic: NM - New Materials
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OPTIMIZATION OF THE SYNTHETIC METHOD FOR OBTAINING GEOPOLYMERS
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MONTAÑO ANGARITA ANGELA MARCELA 1, GONZALEZ CUERVO CLAUDIA PAULINA 2, RUEDA DUARTE LISI MILDRED 3, CHAVARRO AVELLANEDA ANGÉLICA MARÍA 4, URBINA JUAN MANUEL 5,
1 Universidad Industrial de Santander, 2 Universidad Pontifica Bolivariana, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Santander,
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Email: giselle.baron@correo.uis.edu.co
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Abstract: Due to the total CO2 emissions of cement manufacturing industries worldwide, they represent 5-7% of greenhouse gas emissions due to the calcination of limestone, combustión, and transport and manufacturing operations of ordinary Portland cement. Taking into account that the socio-economic development and the exponential increase of the population have significantly increased demand for cement, as an essential material for construction, and with it, the increase in CO2 concentrations in the atmosphere, inorganic polymers have emerged as a viable alternative to be implemented as cementitious materials since they can provide performance comparable to traditional cement with an added value and that these reduce greenhouse gas emissions, specifically CO2 emissions generated by the cement and concrete industries by almost 80%. However, not all geopolymers have viable properties to be implemented as alternative cement. The properties of the inorganic polymer depend on the raw material; the design of the synthesis process is key for the optimization of the properties and consequent final application of the geopolymeric material. It is for this reason that the present study consists of the optimization of the method for obtaining cementitious geopolymers by implementing the industrial calamine residue produced in the Industrias metálicas asociadas IMAL S.A. Bogotá, Colombia. In this company, calamine is generated during the thermal treatment of steel. In this research, the effect of four different parameters of synthesis on the geopolymer mechanical properties was evaluated; for the solid phase, the behavior of the mechanical strength according to the solid/liquid, calamine: sand ratio was studied. In the liquid phase, the Na2SiO3:NaOH ratio and initial concentration of NaOH present in the alkaline solution were evaluated. Results obtained showed that calamine is a functional raw material to produce cementitious inorganic polymers through the geopolymerization technique. Geopolymeric material formed exhibits a maximum value of mechanical resistance equal to 18.04 MPa under the optimum conditions here stablished: solid/liquid ratio: 3.5 g/mL, Na2SiO3:NaOH 9:1, calamine: sand 10:0 and [NaOH]= 10 M.
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Topic: NM - New Materials
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RESEARCH OF PHYSICOMECHANICAL PROPERTIES OF NATURAL FABRICS COATED ON THERMOSETTING COMPOUNDS OF GRAPHENE OXIDE AND POLYURETHANE RESIN FOR REINFORCEMENT OF TRC (TEXTILE REINFORCED CONCRETE) COMPOSITES
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DÍAZ RAMÍREZ GERMAN A. 1, MEJÍA OSPINO ENRIQUE 2, GUTIÉRREZ NIÑO NELSON 3, CRUZ RICARDO 4, SANCHEZ SANTANA VALENTINA 5, ROJAS HERRERA DANIEL ANDRÉS 6, BALLESTEROS RUEDA LUZ MARINA 7,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Santander, 6 Universidad Industrial de Santander, 7 universidad Industrial de Santander,
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Email: luzmabal@uis.edu.co
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Abstract: Concrete is a conglomerate mixture composed of cement and aggregates with the ability to harden when dries and, due to its mechanical capabilities, is widely used in construction. It is usually reinforced with corrugated steel to improve its deformation capacity; however, its usage can become expensive in certain applications. the present research work evaluates the mechanical properties of an alternative support material for precast concrete, composed of fique covered with polyurethane resin and graphene oxide (PUOG), was carried out with the objective of determining the contribution of the material to the enhancement of the mechanical characteristics of precast concrete.
The methodology carried out consisted of four phases, the first phase consisted of the application of the PUOG coating on the fique fabric by the usage of a paint roller and the recording of our procedure, the second phase was the characterization of the reinforcement via the tensile test of the material to determine what amount of coating applied, called "layers", of the 3 levels chosen provides better tensile strength, the characterization by gravimetry of the amount of PUOG applied and FTIR spectroscopy of the characteristic vibration of the graphene oxide coating and its variation between each layer of coating. In the third phase, tensile tests were carried out on the reinforcing compound of fique fabric - concrete, to determine the tensile strength provided to the concrete by comparing four samples with reinforcement of non-coated fique fabric and coated fique fabric with the PUOG coating. In the fourth phase, the analysis of resistance to interfacial shear strength was done via pull-out extraction tests and the later characterization of the fractures of the pull-out tests by the usage of SEM microscopy, in this phase were also used 4 samples of non-coated fique fabric and fique fabric with PUOG coating.
Considering the results obtained in phase 1 and 2, the behavior of the fabric with two layers of coating achieved greater surface coverage and tensile strength than the non-coated fique fabrics, due to the results, it was determined to use fabric with two layers of coating for the realization of phase 3 and 4.
the results obtained in phase 3 (compound tensile tests) were carried out using fique fabric reinforcements with two layers of coating, achieving a maximum force of 3601 N and an average force of 2986 N were obtained, comparing with the results obtained with non-coated fique tissues, there was an increase of 26.89%. The extraction tests (Pull-out) carried out in phase 4, showed a maximum interfacial shear strength of 0.939 MPa with the two-layer coated fique fabric reinforcement.
From the results obtained, it was concluded that the application requires a sufficient coating to properly cover the fabric, and it provides improvements to the tensile strength and interfacial shear strength of the fabric-cement interface. This research will open doors to new alternatives when the production of graphene oxide in industrial quantities is improved and optimized, and an effective application method of the resin is designed for an industrial scale.
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Topic: NM - New Materials
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RICE HUSK AS A SUSTAINABLE SOURCE FOR THE SYNTHESIS OF GRAPHENE OXIDE
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ARRIETA ALMARIO ALVARO 1, VEGA VEGA YAIR ALFONSO 2, MORALES ESCOBAR DAYANA PAOLA 3,
1 Universidad de Sucre, 2 Universidad de Sucre, 3 Universidad de Sucre,
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Email: paolaescobar21@hotmail.com
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Abstract: The purpose of this work was to synthesize graphene oxide from CA, in turn optimizing the variables temperature and time, to maximize the yield and quality of the carbon. Methods: Rice husks from the region were collected, washed with water, and subsequently dried at 60 ºC for 24 h. Then, an experimental design was carried out to find both the temperature and the optimal heating time of the CA in the oven, in which approximately 20 g of CA were weighed and heated in a muffle at different temperatures (300, 400, and 500 °C) and times (0.5, 1.0, 2.0 and 3.0 h). Once the different tests were carried out, each one of the samples was weighed to calculate the yield percentage (%R) of the graphite obtained. The samples that presented a %R equal to or greater than 50 % were macerated and sieved in a 160 µm sieve to then characterize the obtained graphite by Fourier transform infrared spectroscopy (FTIR). Finally, the results were statistically analyzed with the Minitab v.19.1 software to set the optimum values for temperature and time. Now, with the graphite obtained, graphene oxide was synthesized using the modified Hummers method, using sodium nitrate (NaNO3), sulfuric acid (H2SO4), and potassium permanganate (KMnO4) as the main reagents of the process. Finally, graphene oxide was characterized by Fourier transform infrared spectroscopy. Results and discussion: The optimization indicated that the best performance and quality of the graphite is obtained at a temperature of 300 °C for 0.5 h, since as the temperature and time increase, there is a greater mass loss due to thermal decomposition. Likewise, the internal part of the husk experiences a higher temperature compared to other parts of it, preventing the organic component from being completely calcined. At the lowest temperatures and times, darker shades were observed, that is, it is richer in carbon. However, as the temperature and time increased, a white hue was observed due to the presence of ash, indicating the increase of silica in the sample. The FTIR spectrum showed a characteristic peak between 1100 and 1000 cm-1 corresponding to the vibration of the Si-O-Si bonds, confirming that CA ash was obtained. Regarding the synthesis of graphene oxide, the added KMnO4 reacted with H2SO4 forming Mn2O7, which is a highly selective oxidizing agent on double-bonded aromatic compounds, and which has important implications in the structure of graphite and in the mechanisms reaction during oxidation and obtaining graphene oxide. For the characterization of the latter, IR spectroscopy was used, which evidenced the presence of functional groups associated with graphene oxide. Conclusions: The parameters that determine the characteristics of the carbonaceous material in the combustion of AC are temperature and time, obtaining the maximum performance and quality at 300 °C and 0.5 h. Therefore, it was possible to obtain graphene oxide from rice husk residues using the modified Hummers method. Acknowledgments: The authors acknowledge the Ministerio de Ciencia, Tecnología e Innovación (Minciencias) for financing the project identified with BPIN 2020000100027 with resources from the SGR - General Royalty System and the Universidad de Sucre for the financial support provided through the Call for Strengthening Research Groups of the Universidad de Sucre 2018-2019; approved by resolution No.16 of 2020 of the Academic Council.
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Topic: NM - New Materials
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STRUCTURAL, COMPOSITIONAL, MORPHOLOGICAL, OPTICAL AND MAGNETIC RESPONSE OF THE CALATIFEO6 DOUBLE PEROVSKITE
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AVELLANEDA MARTÍNEZ JESÚS DAVID 1, IBAÑEZ SOTELO JOAN SEBASTIAN 2, VELASQUEZ MOYA XIMENA AUDREY 3, PARRA VARGAS CARLOS ARTURO 4, LANDINEZ TELLEZ? ?DAVID ARSENIO 5, ROA-ROJAS JAIRO 6,
1 Universidad Nacional de Colombia, 2 Universidad Nacional de Colombia, 3 Universidad Nacional de Colombia, 4 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 5 Universidad Nacional de Colombia, 6 Universidad Nacional de Colombia - Bogotá,
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Email: jroar@unal.edu.co
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Abstract: The arrival of the transistor as the basis for modern electronics and computation brought to light the potential of solid-state physics to be a big contributor to the improvement and development of new and better technologies. The Perovskite structure ({ABX}_3), given its naturally big spectrum of properties and the straightforwardness of its production, lies among the structures most studied by current material scientists. To increase the range of applicability of this family, the term “complex perovskite” was coined to include structures like the double perovskite ({AA\prime B B\prime X}_3) or more intricate materials. Considering this, device engineering and material architecture constitute an important part of the study of exotic properties and development of new technologies, such as exploiting electronic or nuclear spins as information carriers (spintronics). By designing materials that possess both semiconducting and magnetic properties the sizes of current technology could be reduced considerably. In this work we discuss the synthesis, characterization, and the study of morphological, magnetic and optical of the double perovskite {CaLaTiFeO}_6. The sample was synthesized by a regular solid-state reaction method using the high purity precursor oxide {CaCO}_3, {La}_2O_3, {Fe}_2O_3 and {Ti}_2O_3. Diffractograms for different temperatures during the synthesis process and for the final sample were obtained using a PANalytical X'pert-Pro diffractometer with a copper cathode. A Rietveld Refinement using the GSAS-II software was performed on the final diffractogram, which revealed the structure to be monoclinic in nature with space group {P\ 1\ 2}_1/n\ 1 along with the structure parameters and atomic positions of the material. Use of the micrographs obtained by a TESCAN VEGA scanning electron microscope allowed us to calculate the grain size for each sintering step, where the formation and growth of the grains could be seen clearly. Along with this, the superficial composition of the material was studied with energy dispersive x-ray spectroscopy (EDS). The Reflectance and Absorbance data obtained by the Cary 5000 UV-Vis-NIR spectrophotometer, along with the Kumar method, that our sample possessed an indirect gap of energy slightly higher than that of Germanium. Measurements with a Quantum Design vibrating sample magnetometer (50 K < T < 350 and applied field up to 30 kOe) showed that the material was slightly ferromagnetic at room temperature and possibly presented a high Curie temperature.
Corresponding author: jibanezs@unal.edu.co, jdavellanedam@unal.edu.co
This work was partially supported by DIEB (División de Investigación y Extensión Sede Bogotá – Universidad Nacional de Colombia).
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Topic: NM - New Materials
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STRUCTURAL, COMPOSITIONAL, MORPHOLOGIC AND MAGNETIC FEATURES OF THE RCA2SBFE2O9 TRIPLE PEROVSKITE
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RUEDA CADAVID DIEGO ALEJANDRO 1, HERNÁNDEZ ANDRÉS 2, PARRA VARGAS CARLOS ARTURO 3, SAAVEDRA GAONA INDRY MILENA 4, LANDINEZ TELLEZ? ?DAVID ARSENIO 5, ROA-ROJAS JAIRO 6,
1 Universidad Nacional de Colombia, 2 Universidad Nacional de Colombia, 3 Grupo Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia, 4 Grupo Física de Materiales, 5 Universidad Nacional de Colombia, 6 Universidad Nacional de Colombia - Bogotá,
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Email: jroar@unal.edu.co
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Abstract:
AA'2MM'2O9 triple perovskites allow the A- and M-site cations to be varied, tripling the elemental cell in a structure in which physical properties can be tuned by the inclusion of various elements from the periodic table. When the A and A' sites are occupied by rare earth and alkaline earth cations, while M and M' by magnetic transition metals, it is possible to produce new materials with strong ferromagnetic properties at temperatures close to 300 K, making technological applications at high temperatures feasible. In this work, we report the synthesis and characterization of the triple perovskite material RCa2SbFe2O9 (La, Sm, Eu, Gd, Dy) not yet reported in the literature. Samples were produced by the solid-state reaction method from high purity precursor powders of La2O3, CaCO3, Sb2O3 and Fe3O4, which were mixed in stoichiometric proportions, according to the proposed chemical formula RCa2SbFe2O9. The crystallographic characterization was performed by X-ray diffraction (XRD) experiments using a PanAlytical X'Pert PRO-MPD equipment, which uses CuKα=1.540598 Å radiation. Measurements were performed in the 2 range between 10° and 90°, with a speed of 0.02 o/s. The analysis of the XRD patterns was performed by Rietveld refinement through the GSAS code that allows to establish the crystallographic parameters, structural distortions, and microstructural defects. The surface and fracture morphology were studied by scanning electron microscopy (SEM) by a VEGA3 TESCAN equipment and the composition was analyzed by energy dispersive spectrometry (EDS). SEM micrographs evidence a strongly granular morphology and EDS spectra show that the chemical composition of the samples agrees well with the nominal values of the stoichiometric formula. Measurements of magnetization as a function of temperature and as a function of applied field were performed using a PPMS VersaLab Quantum Design SQUID, on curves of magnetic susceptibility as a function of temperature, following the ZFC (Zero Field Cooling) and FC (Field Cooled) procedures, as well as magnetization as a function of applied field. The results suggest the occurrence of magnetic ordering at temperatures close to 300 K and strong magnetic anisotropy components at low temperatures, due to the distorting effects of the crystalline structure.
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Topic: NM - New Materials
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STUDY OF DODECYLAMINE FUNCTIONALIZED GRAPHENE OXIDE AS A MOLECULAR SURFACTANT IN WATER/OIL SYSTEMS
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CEPEDA MARÍN GLADYS ROCÍO 1, CABANZO HERNÁNDEZ RAFAEL 2, MEJÍA OSPINO ENRIQUE 3, ARENAS BRAYAN 4,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander,
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Email: brayan.arenas@correo.uis.edu.co
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Abstract: Graphene oxide (GO) is a derivative of graphene obtained from the oxidation and chemical exfoliation of graphite. Its lamellar structure is mainly conformed by carbons that change from sp2 hybridization (typical of graphene) to sp3 by covalent bonding with oxygen atoms coming from carbonyl, carboxyl, hydroxyl, and epoxide functional groups formed during the oxidation process (Dimiev & Tour, 2014). The presence of these functional groups randomly distributed in the basal plane and at the edges of GO gives it a hydrophilic character that favors its dispersion in polar solvents, however, GO is an amphiphilic material because it retains in its basal plane pristine graphene domains that are hydrophobic. Despite the amphiphilicity, the diffusion of GO sheets to the interface is slow and the surface/interfacial activity is low (Valtierrez-gaytan et al., 2017), however, this can be adjusted by modifying the oxidation degree, the sheet size, the pH and the salinity of the medium or by covalent functionalization with different molecules through oxygenated functional groups (He et al., 2013; Kim et al., 2010; Yang et al., 2018).
Recently, studies have been published on the chemical functionalization of GO with alkylamines by amidation reactions with carboxylic acids at the edge of the sheets and nucleophilic substitution reactions with epoxides on the basal plane. Lin et al. and Shanmugharaj et al. obtained superhydrophobic GO surfaces with improved thermal stability after functionalization with octadecylamine and hexylamine(Lin et al., 2010; Shanmugharaj et al., 2013). Fei et al. evaluated the emulsifying properties of hexylamine, dodecylamine and octadecylamine functionalized GO by measurements of contact angle, emulsion volume, and average droplet diameter. They showed that these properties depended on the amphiphilicity of GO, since the wettability to oil increased with increasing alkyl chain length and the functionalized GOs formed water in oil Pickering emulsions stable over a wide pH range (Fei et al., 2016). Yang et al. studied the interfacial behavior of GO selectively functionalized with octylamine at a water/oil interface. They found that basal plane functionalization of GO has a greater effect on interfacial tension reduction compared to GO, edge-functionalized GO, and a traditional ionic surfactant (Yang et al., 2018).
The interfacial properties of GO are fundamental to its application in many fields of science and engineering and are inevitably affected by functionalization. So far, there has been little research on these properties in dodecylamine functionalized GO. Therefore, in this work GO was synthesized by the modified Hummers method and functionalized with dodecylamine (GODDA) by amidation and nucleophilic substitution reactions. The obtained materials were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Raman and Thermogravimetric Analysis (TGA). The dispersibility of GO and GODDA was evaluated in water and toluene by bottle test. The wettability of the materials was determined by measuring the material/water contact angle by the sessile drop method and the interfacial tension in toluene/material/water systems by the pendant drop method. The emulsifying properties in these systems were established and their colloidal stability in Pickering emulsions was evaluated by bottle test and Zeta potential at different pH.
FTIR and Raman spectroscopies confirmed the synthesis and covalent functionalization of GO by amidation and nucleophilic substitution reactions. TGA analysis revealed that GODDA has a higher thermal stability. Bottle tests and contact angle measurements showed that GO functionalization increases its hydrophobic character and therefore its dispersibility in toluene. Interfacial tension and Zeta potential measurements showed that GODDA can act as a molecular surfactant at the water/toluene interface reducing the interfacial tension and forming stable Pickering emulsions at pH 2, 7 and 10.
References
Dimiev, A. M., & Tour, J. M. (2014). Mechanism of graphene oxide formation. ACS Nano, 8(3), 3060–3068.
Fei, X., Xia, L., Chen, M., Wei, W., Luo, J., & Liu, X. (2016). Preparation and application of water-in-Oil emulsions stabilized by modified graphene oxide. Materials, 9(9).
He, Y., Wu, F., Sun, X., Li, R., Guo, Y., Li, C., Zhang, L., Xing, F., Wang, W., & Gao, J. (2013). Factors that affect pickering emulsions stabilized by graphene oxide. ACS Applied Materials and Interfaces, 5(11), 4843–4855.
Kim, J., Cote, L. J., Kim, F., Yuan, W., Shull, K. R., & Huang, J. (2010). Graphene oxide sheets at interfaces. Journal of the American Chemical Society, 132(23), 8180–8186.
Lin, Z., Liu, Y., & Wong, C. P. (2010). Facile fabrication of superhydrophobic octadecylamine-functionalized graphite oxide film. Langmuir, 26(20), 16110–16114.
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Topic: NM - New Materials
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STUDY OF THE BIDIMENSIONAL HETEROSTRUCTURE OF GRAPHENE/G-ALN IN THE FRAMEWORK OF DFT
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MURILLO GARCIA JEAN FRED 1, VARGAS OVIEDO ANA ELENA 2, ORTEGA LÓPEZ CÉSAR 3, BERRIO GUSTAVO 4,
1 UNIVERSIDAD DE CORDOBA, 2 UNIVERSIDAD DE CORDOBA, 3 Universidad De Córdoba , 4 Universidad de Córdoba ,
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Email: gberrioc@gmail.com
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Abstract: By means of a first principles study, in the framework of Density Functional Theory (DFT), using the Generalized Gradient Approximation (GGA), implemented in Quantum Espresso (QE) computational package, a graphene/g-AlN lateral heterostructure with different concentrations has been studied. The atomic configurational transition from graphene to g-AlN, through changes in the concentrations of the graphene-like AlN compound, has resulted in changes in the semiconducting character of the material. The substitution of one hexagon of carbon atoms for another of AlN changed the semimetallicity of graphene to a semiconductor with an energy gap of 1.38 eV. As the AlN concentration increased, the changes in semiconducting behavior ranged around 0.5 eV. No surface warping was observed in the monolayer, as well as no magnetism in the material.
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Topic: NM - New Materials
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TWO-DIMENSIONAL ALLOTROPIC STRUCTURES OF III-V BINARY COMPOUNDS. CALCULATION OF FIRST PRINCIPLES.
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MURILLO GARCIA JEAN FRED 1, ORTEGA LÓPEZ CÉSAR 2, VARGAS OVIEDO ANA ELENA 3, BERRIO GUSTAVO 4,
1 UNIVERSIDAD DE CORDOBA, 2 Universidad De Córdoba , 3 UNIVERSIDAD DE CORDOBA, 4 Universidad de Córdoba ,
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Email: gberrioc@gmail.com
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Abstract: By means of a first-principles study, in the framework of Density Functional Theory (DFT), using the Generalized Gradient Approximation (GGA), implemented in the Quantum Espresso (QE) computational package, some two-dimensional allotropies of binary MN compounds of group III-V (M=B, Al, Ga) have been characterized. The different 2D-arrays of AlN exhibit, in their lowest energy state, a semiconducting behavior, with a bandgap between 2 and 2.9 eV, approximately, without geometrical deformation in the direction perpendicular to the monolayer. In the various 2D geometries for BN, the lower energy states have been characterized at pressures below 0.33 kbar, with a convergence threshold of 10-3 a.u. Asymmetric deformations have been observed in the plane of the BN monolayer, with no prevalence of geometrical deformation in the perpendicular direction. Structural stability at minimum pressures of 0.22 kbar has also been obtained in the two-dimensional GaN structures, with no observance of surface warping.
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Topic: OPC - Online Process Control
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APPLICATION OF LIQUID POLYSTYRENE PRODUCTS AS A VISCOSITY REDUCER FOR HEAVY COLOMBIAN CRUDE OILS
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VACA ARÉVALO ANDERSON 1, ARIZA LEÓN EMILIANO 2, LEÓN BERMÚDEZ ADAN YOVANI 3,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: adanleon@uis.edu.co
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Abstract: Heavy and extra-heavy crude oils are of great interest to the petroleum industry, since they are the most abundant fossil fuels at present in comparison with the production of light crude oils. Therefore, due to the difficult process of extraction and transportation of these crude oils, the petroleum industry has seen the need to develop new studies and technologies that facilitate extraction and, at the same time, reduce operating costs. On the other hand, the increase of plastic waste such as polystyrene has been affecting ecosystems, so there is a need to find a solution, and one of them is the transformation into liquid products through the pyrolysis process. In this research, low density expanded polystyrene (LDPE) was subjected to thermal cracking conditions at 430 °C, 400 psi in a nitrogen atmosphere for 40 minutes of reaction. Then, the polystyrene liquid products were applied as a viscosity reducing agent in 3 Colombian heavy crude oils, which presented viscosities in the range of 500 to 16000 cp (@ 30 °C). Meanwhile, the addition of polystyrene liquids with dosages between 0.5 to 7 % in volume, allowed viscosity reductions in the range of 3 to 65 %. However, the results showed greater viscosity reductions in the heavier crude oils. Characterization of the liquid products by infrared spectroscopy (FTIR-ATR) indicated that the polystyrene was transformed into simple aromatic structures with short alkyl chains. This indicates that the dosage of these simple aromatic structures has favorable interactions with the heavy crude oil constituents. Therefore, the thermal treatment of expanded polystyrene and the application of its liquid products are an alternative for the permanent improvement of the properties of heavy crude oils.
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Topic: PAT - Plasma Applications and Technologies
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HIGH TEMPERATURE INFILTRATION BEHAVIOR AND REACTION CHARACTERISTICS OF COLIMA VOLCANIC ASHES ON GADOLINIUM ZIRCONATE COATINGS DEPOSITED BY ATMOSPHERIC PLASMA SPRAYING
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ZARATE-MEDINA JUAN 1, BEDOYA TRUJILLO IVAN FELIPE 2, PÉREZ BEDOLLA JHON SEBASTIAN 3, RIVERA GIL MARCO ANTONIO 4, MUÑOZ-SALDAÑA JUAN 5,
1 UNIVERSIDAD MICHOACAN DE SAN NICOLAS DE HIDALGO, 2 Centro de Investigación y de Estudios Avanzados del IPN, 3 Cinvestav, 4 Institute for Plastics and Advanced Materials, Advanced Technology Center, 5 Centro de Investigación y de Estudios Avanzados del IPN,
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Email: jmunoz@cinvestav.mx
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Abstract: Thermal barrier coatings are severely affected by the infiltration of Si-rich molten airborne particles. In this work, the reaction products of infiltration experiments performed on free-standing gadolinium zirconate (Gd2Zr2O7, GZO) coatings deposited by atmospheric plasma spraying with molten ashes from the active Colima volcano at 1250 oC for 1, 5, and 10 h are presented and discussed. For coatings manufacture, commercial GZO powders, with an average particle size of 83 µm, were sprayed under the following conditions: stand a distance of 75 mm, 0.75 m/s in velocity, feeding rate of 30 g/min, 80 SCFH of hydrogen and 15 SCFH of argon as primary and secondary carrier gas flows, respectively. Characterization of the reaction products between the molten ash with GZO coatings was performed by scanning electron microscopy, chemical composition with EDS, grazing X-ray diffraction on grinded samples at different depths, as well as micro-Raman spectroscopy. Raman spectroscopy revealed that the bands for apatite and cubic zirconia, respectively, are present over the reaction layer, indicating that these phases recrystallize together. GZO coatings exposed to Colima volcanic ashes during 1, 5, and 10 h presented an infiltration depth of around 26.28, 30.23, and 37.90 µm, respectively. Phases were identified to comprehend the infiltration kinetic on these rare-earth zirconate-based coatings.
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Topic: PAT - Plasma Applications and Technologies
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METAL HYDRIDE FILMS PRODUCED BY HYDROGEN TRANSPORT IN A HOLLOW CATHODE
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MUHL STEPHEN 1, PEREZ ARGELIA 2,
1 Instituto de IInvestigaciones en Materiales, Universidad Nacional Autonoma de Mexico, 2 Unidad de Investigación y Desarrollo Tecnológico (UIDT-CCADET), Hospital General de México,
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Email: ekargy@hotmail.com
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Abstract: The fabrication of thin films of polycrystalline silicon using a reversible chemical reaction was described about 30 years ago by the group of Stan Vepřek of the University of Zurich. They reported that pieces of silicon exposed to a low-pressure high-density hydrogen plasma promotied the formation of volatile silicon hydride, this could then be transported within the reactor to a hot substrate where the decomposition of the hydride resulted in the deposition of silicon thin films. Similarly, hydrogen plasmas have also been used for chemical etching of various materials and, for example, in the case of the deposition of diamond films the preferential etching of sp2 bonded carbon is considered to be of fundamental importance for the formation of diamond-like carbon. In this paper we describe the chemical etching of molybdenum and tantalum by atomic hydrogen generated in a RF or pulsed DC plasma-activated in a hollow cathode. The water- cooled cylindrical cathode was lined with the appropriate metal.
The metal hydride vapour generate in the plasma flowed to quartz substrates which were maintained at temperatures greater than 300 oC. Under these conditions the metal hydride was thermal decomposed and a thin film was deposited. A special substrate heater was constructed such that the four quartz substrates used could be simultaneously exposed to the metal hydride vapour, but with each substrate at a different temperature; each approximately 20oC less than the neighbouring one. In this way, depositions under identical conditions could be carried out, but at four different temperatures. We report the deposition rate as a function of the substrate temperature and the plasma power and type applied to the hollow cathode, as well as some of the characteristics of the deposited films.
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Topic: RE - Renewable Energy
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APPLICATION OF DIFFERENTS RANS K-W MODELS IN THE SOLUTION OF TUBULENT FLOW PROBLEMS.
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BARRERA DIAZ CARLOS DANIEL 1, FUENTES DIAZ DAVID ALFREDO 2, JARAMILLO IBARRA JULIÁN ERNESTO 3, MARTÍNEZ MANUEL DEL JESÚS 4,
1 UNIVERSIDAD INDUSTRIAL DE SANTANDER , 2 Universidad Industrial de Santander, 3 UNIVERSIDAD INDUSTRIAL DE SANTANDER, 4 Universidad industrial de Santander,
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Email: mjmartin@uis.edu.co
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Abstract: The purpose of this study is to validate the development of algorithms for solving turbulent flow problems in incompressible Newtonian fluids without thermal effects through the C++ programming language and the implementation of the finite volume method. The RANS equations were applied together with the transport equations of k and ω, and the Boussinesq approximation for the modeling of the Reynolds stresses and the production of k, in addition, the solution for the coupling between velocity and pressure was achieved from the SIMPLE algorithm. The numerical results obtained from the studied turbulence models (k-ω: 1988,1998,2006; k-ω: SST,SST 2003 y k-ω: BSL), were compared against the problems described in the literature of: Plane turbulent channel flow (PTCF) for Reynolds of 395 and 590 based on friction velocity [Moser, R., et al, 1998]; Zero pressure gradient flat plate (ZPGFP) for Reynolds of 5x10^6 based on plate length [Wieghardt, 1951]; Backward facing step (BFS) for Reynolds of 36000 based on the step height [Driver et al, 1985] y Lid-driven cavity (LDC) for Reynolds of 10000 based on cavity length [Ghia, U., et al, 1982], where the average error percentages obtained in the velocity, turbulent kinetic energy and friction coefficient profiles were calculated and compared given the case studied. Finally, a simulation for the PTCF problem for a Reynolds of 1000 based on friction velocity was performed.
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Topic: RE - Renewable Energy
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ECONOMIC AND ENERGY ANALYSIS OF THE USE OF MUNICIPAL SOLID WASTE FOR ENERGY GENERATION AT THE UNIVERSIDAD INDUSTRIAL DE SANTANDER.
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ORTIZ OCHOA FABIO 1, RUEDA ORDOÑEZ YESID JAVIER 2,
1 Universidad Industrial de Santander , 2 Universidad Industrial de Santander ,
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Email: yjruedao@uis.edu.co
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Abstract: The disposal of waste in sanitary landfills and in the open sky is generating serious problems at the national level, the accumulation limit of the main municipal garbage dumps has collapsed, and for this reason, high-impact environmental crises have been generated, in addition to health and economic crises, The main capital cities have had to restructure their collection and disposal system due to the provisional closures, in some cases permanent, of the garbage dumps, but in most cases the solution is the same, to enable another disposal site to begin the accumulation of waste and repeat the bad process that has been carried out.
The methods currently used in the attempt to obtain energy from this waste focus solely on the release of methane, generated through natural biodigestion, in some cases with chemical disintegration procedures, processes that accelerate its decomposition, but with the limitation that It is only carried out in plants suitable for this purpose, and with the same need for considerable spaces for installations. In municipal landfills, the adjustments made to contain contamination by liquid decomposition are artificial pools that in some cases prevent leachate from reaching the bedrock and filtering into the groundwater channels (aquifers), in most cases they are provisional solutions and with a very short duration in time, which is why it does not represent stability for the project, a significant measure in matters of contamination, and a guarantee of safety in matters of public health. Therefore, it is necessary to transform this waste into new products as part of a sustainable circular economy for the country. One of the proposed solutions is the conversion of this matter into energy, which is aligned with the emblematic mission of making an energy transition towards non-fossil fuels. Therefore, this work addresses the thermo-economic analysis of the use of RSU for power generation.
This work proposes the production of char pellets from torrefied MSW. An energy balance is carried out to estimate the dimensions and capacity of the collection and transformation plant based on the availability of waste. The MSW processing into char-like pellets was performed using a muffle furnace (Terrigeno, model D8) and a pelletizer (Oil division Colombia, model 125). First, the sample of 9±1 g was introduced in open Petri plates. Then, to evaporate the moisture, the sample was heated from 26±2 to 106 °C at a heating rate of 10 °C/min, and left for 40 min at the drying temperature. Afterward, for torrefaction, the Petri plates were closed and sealed to avoid oxidation and obtain a quasi-inert atmosphere, and the temperature was increased to 270 °C and left 50 min as residence time. Also, in this stage, the remaining moisture was removed, increased energy density, and obtained the highest possible calorific value from the charcoal present in the MSW. Thus, charcoal pellets from MSW are presented as an important alternative to taking into account energy generation.
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Topic: RE - Renewable Energy
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EXPERIMENTAL THERMAL FATIGUE ANALYSIS OF 316L STAINLESS STEEL FOR APPLICATION IN HIGH TEMPERATURE CONCENTRATED SOLAR POWER (CSP) PLANTS
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ARIAS SABOGAL BRAYAN DANIEL 1, FLÓREZ MERA JUAN PABLO 2, NIETO GARZÓN NURY AUDREY 3,
1 Universidad de Pamplona, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander,
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Email: naniegub@correo.uis.edu.co
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Abstract: Renewable energies contribute to the reduction the greenhouse gases, showing as an important solution in the energy transition. In this context, central tower Concentrated Solar Power (CSP) systems are a promising alternative technology. Currently, two-phase sodium thermosiphons are being studied, aiming their use in the central receiver of a solar power tower due to their high performance as heat exchangers at high temperatures. Sodium is the working fluid of the thermosiphon, so it is important to avoid cracks in its structure. The 316L stainless steel is a material that can be used in the structure of the thermosiphon. An experimental analysis of thermal fatigue of 316L steel was carried out in order to evaluate the possible changes in the 316L steel microstructure when it is submitted to the repetitive temperature changes that occur at the central receiver due to the variable solar radiation throughout the day. An induction furnace was built to thermal fatigue 316L stainless steel samples. The induction furnace allowed that the temperature of steel samples to be quickly raised to 700 °C. Subsequently, the samples were cooled in the environment up to 500 °C. These heating and cooling processes were successively repeated for 500 cycles. Hardness and metallographic tests were performed on a 316L stainless steel sample without thermal fatigue and on three 316L stainless steel samples thermally fatigued. The results of hardness and microstructure were compared and significant changes were not observed. It is suggested further studies of thermal fatigue with a range of higher temperatures and a greater number of cycles.
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Topic: RE - Renewable Energy
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FLAT THERMOSYPHON WELDED BY EPOXY RESIN FOR THERMAL CONTROL OF PHOTOVOLTAIC PANELS
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SANCHEZ ACEVEDO HELLER GUILLERMO 1, FLÓREZ MERA JUAN PABLO 2,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander,
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Email: jpflorez@uis.edu.co
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Abstract: Current processes of transition from fossil energy mix to renewable sources have brought the development of efficient devices. Photovoltaic panels are an important technology in the use of solar energy. Control of the operating temperature is one of the aspects that arouse interest in this technology. Technological solutions that allow thermal control through the rejection or use of absorbed thermal energy are currently being investigated. Flat thermosyphons are one of the solutions used for this purpose. Thermosiphons are devices that use the phase change of a working fluid to transport thermal energy with low-temperature gradients. Thermosiphons are originally formed by a hollow tube closed at both ends. The bottom section absorbs the heat and produces the evaporation of the working fluid. The generated steam flows through the internal section of the tube to the upper region where the heat is rejected, producing the condensation of the fluid again. The condensate returns to the bottom region by the action of gravity. Recent developments and applications of additive manufacturing technologies have allowed the manufacture of flat geometry thermosiphons through the joining of metal sheets by diffusion welding. However, specialized equipment and exhaustive cleaning and preparation processes do not favor its economic viability in applications such as photovoltaic panels. Other forms of union that allow the operation of thermosiphons are necessary. In this work, a flat thermosiphon using an epoxy resin for joining metal sheets is built. Performance tests of the thermosiphon built using this method are conducted on an experimental bench. Several experimental operating conditions are reproduced in order to simulate the variable thermal loads and to evaluate the sealing capacity and mechanical and thermal resistance of the epoxy resin.
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Topic: RE - Renewable Energy
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HYDROGEN PRODUCTION THROUGH THE ELECTROLYSIS PROCESS OF PRODUCTION WATERS FROM THE LA CIRA INFANTAS OIL FIELD.
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LEÓN BERMÚDEZ ADAN YOVANI 1, JIMÉNEZ CABALLERO MICHELL ANDREY 2, PEÑA BALLESTEROS DARIO YESID 3, GUERRA LOPEZ JULIO CESAR 4, GARCÍA MÁRQUEZ ROBINSON GARCÍA MÁRQUEZ 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, UIS, 4 UNIVERSIDAD INDUSTRIAL DE SANTANDER, 5 UNIVERSIDAD INDUSTRIAL DE SANTANDER,
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Email: Robeengarcia@gmail.com
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Abstract: The purpose of this research was to evaluate the generation of hydrogen on a laboratory scale from the electrolysis of production waters from “La Cira Infantas” field for its potential use in the industry. It is important to highlight that the parameter of the water-oil production ratio (WOR) in this field is around 14; thus, it is necessary to apply efficient practices with the environment.
Electrolysis tests were performed using an EC570-90 power supply and graphite electrodes. Initially, a mixed 2x3x3 experimental design was generated taking salinity concentration levels (2000 and 20000 mg/Lt), 3 amperage variations (100-150-200 mA), and 3 pH variations (4-7-10). The volume of hydrogen produced for each of the tests was measured for 15 minutes.
The data obtained was recorded in the Statgraphics 18 software, therefore, the statistical parameters showed that the most important and influential variable in the proposed design was the intensity of the current, followed to a lesser extent by salt concentration. It was evidenced that the pH had an insignificant effect on the process. The results demonstrated that the use of production waters for the generation of hydrogen by electrolysis can be scaled in different production waters. Likewise, the implementation of electrolysis with alternative technologies can be considered as a sustainable energy vector, which can complement the energy required in the extraction stages and different surface activities for the oil industry.
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Topic: RE - Renewable Energy
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MODELING, SIMULATION AND ANALYSIS OF THE MECHANICAL BEHAVIOR OF THE BLADE OF A VERTICAL AXIS WIND TURBINE IN THE CHICAMOCHA CANYON IN SANTANDER.
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BAYONA NIXON 1, CHACÓN VELASCO JORGE LUIS 2, ROSERO ARIZA JUAN DIEGO 3, GONZALES SILVA GERMAN 4,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander , 3 Universidad Industrial de Santander , 4 Universidad Industrial de Santander,
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Email: german.gonzalez@correo.uis.edu.co
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Abstract: In recent decades, the interest in energy harnessing and the correct use of resources in a clean and environmentally friendly way has expanded due to the global increase in energy demand. This has led to the search for the development of energy capturing machines with better design characteristics. To achieve this, it is necessary to study several materials that are easy to recycle and have low environmental impact, possessing the necessary characteristics for application in the study area. Currently, H-type Darrieus vertical axis wind turbines use synthetic or composite materials for the manufacture of their blades, which generate solid waste that is difficult to dispose of at the end of their life cycle. In this research, the use of an easily recyclable composite material called Nylon X was proposed as a solution. Nylon X is a thermoplastic polymer belonging to the family of reinforced polyamides with carbon fiber filaments. When it loses its properties, it can be reused for the manufacture of the same blades. Using the finite element method, a CDF analysis was performed with the DUE06W200 aerodynamic profile, which according to consulted references, presents better performance in the selected study area. To do this, a blade of these wind turbines was modeled, simulating under the specific conditions of the Chicamocha Canyon. The results showed that the total deformations with the proposed material under the study conditions were minimal and that Nylon X material along with the design presents good conditions of structural resistance for the use of low-power wind energy generation in the Chicamocha Canyon in Santander.
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Topic: RE - Renewable Energy
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PHYSICAL-CHEMICAL AND MICROBIAL PARAMETERS RELATIONSHIP OF DOMESTIC WASTEWATER TREATED BY UASB REACTOR IN BIOGAS GENERATION PROCESS
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MARTINEZ AMARIZ ALEJANDRO DAVID 1, MANTILLA MORENO ANA 2,
1 Universidad de Santander, 2 Universidad de Santander,
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Email: anamariammoreno@gmail.co
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Abstract: Biogas is a biofuel little used in Latin America, especially in Colombia. Its generation through anaerobic processes is an environmental alternative not only as a biofuel, but also because using methane contributes to reducing greenhouse gas emissions. This work analyzes the relationship between physical-chemical and microbiological parameters that influence the generation of methane in anaerobic treatment processes such as Up flow Anaerobic Sludge Blanket (UASB) of Municipal Wastewater. Thus, the operation of UASB reactors in the metropolitan area of Bucaramanga is initially exposed, based on a bibliometric analysis on the subject. Second, the physical-chemical-microbiological characterization is presented, carried out during the first semester of 2021, of municipal wastewater samples, taken from a Wastewater Treatment Plant in Floridablanca, Colombia. Among the results obtained from the analysis, the determination of total and fecal coliforms, microbial consortiums in the anaerobic digestion process, together with the averages of pH, Temperature, Alkalinity, sediment solids with an average removal of chemical oxygen demand (COD) of 60 %. Finally, it concludes with the comparison and relational analysis of the values obtained in the characterization with those found in the current literature until July 2021.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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BIBLIOMETRIC STUDY OF THE APPLICATION OF INDUSTRY 4.0 IN PROCESS CONTROL THROUGH SCOPUS AND WEB OF SCIENCE DATABASES (2013 – 2022)
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CRUZADO YESQUÉN KATHIA YOMARA 1, ALVIZ MEZA ANIBAL 2, VASQUEZ CORONADO MANUEL HUMBERTO 3, TORRES SALAZAR EDWIN ALDAIR 4, CASTAÑEDA HIPOLITO MARILYN LORENA 5, GASTIABURÚ MORALES SILVIA YVONE 6, ALVAREZ VASQUEZ HALYN 7,
1 Universidad Señor de Sipán, 2 Universidad Señor de Sipán, 3 Universidad Señor de Sipán, 4 Universidad Señor de Sipán, 5 Uniersidad Señor de Sipán, 6 Universidad Señor de Sipán, 7 Universidad Señor de Sipán,
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Email: avasquezh@uss.edu.pe
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Abstract: Industries interested in offering their products or services to the consumer and supplier are always focused on quality and productivity expectations, respectively. Quality and productivity are as much value as the integrity of the processes. This integrity is typically recognized as process control, which refers to analyzing, monitoring, supervising, and performing activities such as planning, mapping, and automatization. On the other hand, industry 4.0 has emerged as a series of technological tools that can be incorporated into several industrial facilities. This research aims to carry out a bibliometric analysis of the application of industry 4.0 in process control from 1972 – 2022 through Scopus and Web of Science databases. The studied data were extracted from the citation, bibliographic, abstract, and keyword information released by the collected articles. These data were processed in RStudio and VOSviewer. As a result, it was observed that the delivery of articles is under exponential growth. In addition, it was found that the most cited articles are related to the detection of anomalies in process control by using deep and automatic learning as the preferred technology to improve decision–making.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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BIBLIOMETRIC STUDY ON THE IMPACT OF INDUSTRY 4.0 ON BUSINESS MANAGEMENT IN THE DECADE (2013-2022)
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CRUZADO YESQUÉN KATHIA YOMARA 1, ALVIZ MEZA ANIBAL 2, VASQUEZ CORONADO MANUEL HUMBERTO 3, TORRES SALAZAR EDWIN ALDAIR 4, CASTAÑEDA HIPOLITO MARILYN LORENA 5, GASTIABURÚ MORALES SILVIA YVONE 6, ALVAREZ VASQUEZ HALYN 7, SAAVEDRA RUÍZ ERINSON JOSÉ 8,
1 Universidad Señor de Sipán, 2 Universidad Señor de Sipán, 3 Universidad Señor de Sipán, 4 Universidad Señor de Sipán, 5 Uniersidad Señor de Sipán, 6 Universidad Señor de Sipán, 7 Universidad Señor de Sipán, 8 Universidad Señor de Sipán,
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Email: sruizerinsonjos@crece.edu.pe
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Abstract: Sustainability and competitiveness in the business world demand constant innovation, linked to the introduction of emerging technologies that enable efficient management in the manufacturing industry. Industry 4.0 has had a significant impact on all business fields since its areas of application include human resources, customer relationship management, marketing, finance, and production departments. Applying these tools allows the interrelation of operational areas, aiming to increase productivity. Therefore, through this research, it is intended to perform a descriptive bibliometric analysis, regarding the impact of Industry 4.0 on business management during the last decade (2013-2022). Articles indexed in the Scopus and Web of Science databases were analyzed based on the data extracted from their indicators of citation, bibliography, abstract, and keywords. This data was analyzed in the RStudio and VOSviewer. As a result, we found that the production of articles on the studied subject in recent years has grown exponentially in both databases. The principal technologies included in the manufacturing process were linked with artificial intelligence and big data. The most cited articles indicate that intelligent manufacturing is becoming highly relevant in process optimization. This bibliometric analysis suggests that the insertion of Industry 4.0 in organizations has a positive impact on decision-making, improving the direction of business management.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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DEVELOP OF A COOLING SYSTEM USING SOLAR ENERGY FOR THE ARTISANAL FISHING INDUSTRY
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GARCIA RICARDO 1, GARCIA SHIRLEY 2, ESPELETA ALVARO 3, PIMIENTA LINA 4, NARVAEZ FRANCISCO 5,
1 Universidad Francisco de Paula Santander Ocaña, 2 Universidad del Magdalena, 3 Universidad del Magdalena, 4 Universidad del Magdalena, 5 Universidad del Magdalena,
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Email: fnarvaez@unimagdalena.edu.co
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Abstract: Fishing activities require optimal fish conservation conditions in order to reduce their deterioration in such a way that their quality is maintained within the supply chain. The present work intends to guarantee the conservation of the catch obtained in tasks aboard artisanal parguera boats in the Taganga area in the city of Santa Marta, through the calculation and design of a prototype of an autonomous cold conservation system, using renewable energies. The field activity of the model boat was carried out at the Universidad del Magdalena. In this way, a refrigeration system capable of achieving a drop in seawater temperature between 0 and -1.5 °C was built. PID controller was produced in order to monitor the refrigeration system remotely. The total estimated load for the hold of the vessel used for cooling seawater is 0.86 TR and, with an economic analysis of the costs of equipment and assembly of the project, the estimated value is $20,440,460 COP and its impact on the price of the product is estimated at $228.54/Kg COP.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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EXPERIMENTAL EVALUATION OF CUTTING FORCES FOR TIRE RECYCLING TOOLS.
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CARDENAS FLECHAS LEYDI JULIETA 1, TERÁN LLORENTE LEONEL ALVEYRO 2, RUIZ PINEDA LUIS FERNANDO 3, HINCAPIÉ LADINO DUBERNEY 4,
1 Fundación Universidad de América , 2 Fundación Universidad de América , 3 Fundación Universidad de América, 4 Fundación Universidad de América ,
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Email: duberney.hincapie@profesores.uamerica.edu.co
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Abstract: The management of used tires and their waste is a problem that must be addressed in a comprehensive and sustainable manner, considering all aspects related to their design, manufacturing, and final use. In turn, transportation and cutting are key issues in the tire recycling process, seeking to minimize the amount of waste generated and establish new uses for recovered materials. Therefore, in this study, the shear stresses and shear forces for a blade profile commonly used in the processing of this type of materials were experimentally evaluated. These data will be used for the validation of numerical models used in the determination of the most suitable blade profile.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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HYBRID KINEMATIC SIMULATION OF HUMAN GAIT PATTERN FOR DIFFERENT VELOCITIES
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IZQUIERDO CÓRDOBA LUIS 1, AMAYA HURTADO DARÍO 2, ROSÁRIO JOÃO MAURÍCIO 3,
1 Fundación Universidad de América, 2 Universidad Militar Nueva Granada, 3 Universidade Estadual de Campinas,
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Email: rosario@fem.unicamp.br
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Abstract: The purpose is to propose a hybrid kinematic model of a serial biped robotic mechanism that can simulate human gait in the sagittal plane while considering four different velocity patterns. To achieve this, we conduct a thorough biomechanical analysis of human gait movements. Specifically, we consider the lower limbs as kinematic chains that are composed of joints and rigid links. To obtain the necessary data for our analysis, we employ a sophisticated tracking system that records the angular trajectories and XY positions of the hip, knee, and ankle joints. This procedure was carried out at the Laboratory of Instrumentation for Biomechanics at the Faculty of Physical Education at the UNICAMP. We collected data for four different walking speeds, which enables us to simulate the effects of age or pathological disturbance on gait. By using this dataset, we can accurately generate the velocity patterns required for our hybrid kinematic model.
We use an iterative numerical method to simulate the hybrid kinematic model and solve the inverse kinematic problem, which generates the desired trajectories in joint space. Additionally, we incorporate a Finite State Machine (FSM) to describe the variable event-based gait model. One of the initial steps in gait modeling is identifying the main events that occur during the gait cycle, such as heel strike and toe-off, which serve as key reference points for subsequent analysis. To detect these events, we use various data sources, including kinetic and/or kinematic data, which provide information on the forces and movements acting on the body during gait. The simulation is performed in Matlab/Simulink using the Stateflow library, where the Gait desired velocity is the event that determines the switching between FSMs for each velocity pattern.
Continuous dynamics play a crucial role in gait modeling, as they describe the temporal evolution of physical variables, such as joint angles and ground reaction forces, throughout the gait cycle. On the other hand, event dynamics typically govern abrupt changes in the behavior of the system, such as the initiation of the swing phase or a change in walking speed. Based on the hybrid dynamic modeling, it is possible to design a control architecture for a lower limb exoskeleton during a gait cycle, structured as a hierarchical system. The decision layer, located at the uppermost level, includes a discrete event controller, which in this case corresponds to a finite state machine. The lower layer comprises a continuous joint-level controller, which can be implemented as a PID controller to accurately track the reference angular trajectory in the respective degree of freedom of the lower limb. This proposed architecture allows for effective control of the exoskeleton's motion, providing precise and reliable assistance during gait rehabilitation.
Our results demonstrate that hybrid modeling provides significant advantages in modeling robotic systems, such as exoskeletons or biped robots. It allows for the consideration of discontinuities and the ability to adapt the gait pattern in real-time with variable velocity. In future work, this approach will help us incorporate advanced machine learning algorithms to further enhance the exoskeleton's performance and adaptability to varying patient needs.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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NUMERICAL ANALYSIS OF SHARPENING PROFILES FOR TIRE RECYCLING CUTTING TOOLS
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CARDENAS FLECHAS LEYDI JULIETA 1, HINCAPIÉ LADINO DUBERNEY 2, RUIZ PINEDA LUIS FERNANDO 3, TERÁN LLORENTE LEONEL ALVEYRO 4,
1 Fundación Universidad de América , 2 Fundación Universidad de América , 3 Fundación Universidad de América, 4 Fundación Universidad de América ,
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Email: leonel.teran@profesores.uamerica.edu.co
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Abstract: Recycling end-of-life tires (ELTs) is a major challenge in waste management, as tires are not biodegradable and, if not adequately treated, can cause problems for human health and the environment. The transfer of ELTs from waste collection points to recycling facilities is one of the main problems in the recycling process, since as an entire piece, they occupy a large volume, representing high costs and delays in transportation. Therefore, a possible solution is to carry out a pre-cutting process at the collection points to reduce the volume and facilitate transportation. Cutting processes play an essential role, so the devices used in this operation must be efficient to maintain the minimum energy consumption. In this study, several blade profiles are numerically evaluated to find the most efficient one regarding the required cutting force of the tire tread. Then, the cutting edge of the best profile is analyzed to estimate its wear rate based on a simple fatigue failure criterion, to recommend the frequency of blade sharpening.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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STRENGTHENING OF THE PRODUCTIVE CHAIN OF SACHA INCHI IN THE ANCESTRAL KITE KIWE COMMUNITY: ANALYSIS OF PLANTING AND TRANSFORMATION INTO DERIVED PRODUCTS.
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FERNANDEZ INGRID MILENA 1,
1 Fundación Universitaria de Popayan ,
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Email: ingrid.fernandez@docente.fup.edu.co
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Abstract: Sacha Inchi (Plukenetia volubilis) is an oilseed plant with great agro-industrial potential, which has been widely used as food by communities in the Latin American Amazon. Its cultivation has expanded in recent years due to its nutritional value and potential in the food and cosmetics market, due to its high concentration of proteins, vitamins, antioxidants and omegas 3, 6 and 9. The Kite Kiwe ancestral community located in the municipality of Timbío in the department of Cauca (Colombia), currently processes this seed in an artisan way under their cultural traditions. Thus, the objective of this work was focused on determining the parameters for the standardization of Sacha Inchi planting and harvesting in this region and establishing the transformation route of the raw material into oil, as well as identifying the possible uses of the derived products.
A bibliographical review was carried out on the methods of harvesting and harvesting Sacha Inchi, the specific parameters were defined in each stage, analyzing the methods used by different farmers, articulating it to the process carried out in the community, the steps for oil extraction were found. of the seed according to different methods and possible derived products will be used.
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Topic: SETISI - Science, Engineering, Technology, and Innovation for Social Inclusion
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WATER DESALINATION PLANT AS AN EMERGENCY ALTERNATIVE IN EDUCATIONAL INSTITUTIONS OF LA GUAJIRA, COLOMBIA
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RIOS DIAZ YENNIFER YULIANA 1, GARNICA A. VALENTINA 2, DÍAZ MÁRQUEZ M. SANTIAGO 3, PRIOLÓ J. PABLO 4, CARRILLO CABALLERO GAYLORD 5,
1 Universidad Industrial de Santander, 2 Universidad Tecnológica de Bolívar, 3 Universidad Tecnológica de Bolívar, 4 Universidad Tecnológica de Bolívar, 5 Universidad Tecnológica de Bolívar,
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Email: gcarricaballero3@hotmail.com
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Abstract: The supply of potable water is a global challenge, especially in coastal regions such as the Atlantic coast of Colombia, La Guajira, and Magdalena, where water scarcity is a constant problem affecting children and young people, limiting schools in the region from providing basic hygiene and food services, causing infections and, in most cases, absence of students in educational institutions.
To address the problem of water scarcity in Colombia's coastal regions, local governments have adopted strategies such as water rationing and new technologies to take advantage of nearby water resources. However, many technologies are costly and challenging to implement, requiring more efficient and cost-effective alternative solutions.
In this regard, this project proposes the development of a water desalination plant that functions as an emergency alternative for obtaining potable water from seawater. Solar distillation technology presents an effective solution to this problem of desalinating water, as it uses the energy from the sun to evaporate water and separate it from its salts and other contaminants. The proposed solar desalination system consists of a parabolic dish solar concentrator built with mirrors and an aluminum receiver, a reactor where heat transfer occurs. Water vapor is obtained thanks to the temperature increase on the surface by solar radiation.
This system aims to produce a maximum of 1000 liters of water for common uses per day, making it an efficient and cost-effective alternative for educational institutions with fewer students and difficulties in the water supply.
This solar distillation technology is selected because the area where the project is developed, in this case, La Guajira, has a great energy potential in using solar radiation as a constant and accessible renewable energy source of 4.5 Kilowatts per square meter on average per day. The solar distillation process is safe and easy to use, making it suitable for supplying potable water in remote regions or emergencies.
The solar desalination system has three subsystems that contribute to process efficiency:
A heat exchanger system that accelerates the cooling process of the already distilled water vapor to obtain a greater liquid flow
A fluid distribution system
A level control system that ensures the proper water level in the reactor to optimize distilled water production
A modular approach is used to construct the solar desalination system prototype, as it facilitates manufacturing and transport. Additionally, the prototype uses materials resistant to corrosion and weathering to ensure the system's durability in the marine environment. The structure of the parabolic disc concentrator is a galvanized 14-gauge wire mesh on which mirrors are used to reflect the sun's rays onto the copper receiver.
To ensure remote monitoring and operation of the system, field, and control devices are employed to measure variables correctly and adjust flow and pressure values at different points in the system. This strategy allows for early detection of failures and preventive system maintenance.
Once the prototype is built and tested, its efficiency, performance, and operating costs are evaluated to optimize the system's design and prepare its implementation on a large scale in the Colombian Caribbean region. Then, the system's scalability is sought by using the relationship between the solar collector's surface, the amount of water that can be desalinated per day, and the relationship between the cost of materials and the system's production capacity.
It is expected that the large-scale implementation of a solar desalination system will significantly improve access to potable water in the Colombian Caribbean region, especially in areas where water supply is limited or nonexistent. Furthermore, this renewable and sustainable technology can help reduce dependence on non-renewable energy sources such as fossil fuels and promote the development of clean and environmentally-friendly technologies.
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Topic: SI - Structural Integrity
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EVALUATION OF EQUIVALENT STRESS INTENSITY FACTOR MODELS UNDER MIXED MODE FRACTURE IN LOW CARBON STEEL
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GÓMEZ GAMBOA ESTEFANÍA 1, DIAZ JORGE G 2, MANTILLA VILLALOBOS JAIRO ANDRÉS 3, BOHORQUEZ BECERRA OSCAR RODOLFO 4, MARTÍNEZ MANUEL DEL JESÚS 5,
1 Universidad Industrial de Santander , 2 UIS, 3 Universidad industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad industrial de Santander,
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Email: mjmartin@uis.edu.co
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Abstract: This study aims to determine the equivalent stress intensity factor (SIF) model that best fits the experimental behavior of low carbon steel under mixed mode fracture I and II. The SIF models of Tanaka, Asaro, Pook, and Richard were evaluated. The theoretical values used for comparison correspond to experimental results in a modified C(T) geometry by machining a hole in the region near the crack, subjected to fatigue loads with a load ratio of R = 0.1. The SIF of six experimental points was compared with the values computed through the models. To analyze the prediction in the estimated number of cycles, the Paris, Paris-Erdogan, and modified Forman-Newman crack growth models were used with each equivalent SIF. It is concluded that the modified Forman-Newman model has the best prediction since the error between the calculated and experimentally recorded number of cycles is the lowest. Additionally, it was observed that Richard's equivalent SIF implies a conservative approach in the element's life, with increasing errors from -1.69% at the start of growth up to 71% at the end of the calculation.
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Topic: SI - Structural Integrity
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EVALUATION OF NOPAL ON CORROSION PHENOMENA IN STRUCTURAL STEELS BY ELECTROCHEMICAL EVALUATIONS.
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LARA CUSBA MICHAEL GEOVANY 1, HERNÁNDEZ CARRILLO CARLOS GABRIEL 2, TORRES GÓMEZ ROBINSON DE JESÚS 3, MUJICA RONCERY LAIS 4, PINEDA TRIANA YANETH 5,
1 Universidad Pedagógica y Tecnológica de Colombia , 2 Universidad Pedagógica y Tecnológica de Colombia , 3 Universidad Pedagógica y Tecnológica de Colombia , 4 Universidad Pedagógica y Tecnológica de Colombia, 5 Universidad Pedagógica y Tecnológica de Colombia,
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Email: Yaneth.pineda@uptc.edu.co
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Abstract: Inhibitors as corrosion mechanisms have allowed to increase the integrity and durability of structural elements. When applied, they generate a slowing down of the corrosion rate. However, it is required the constitution of materials that support and contribute to the reduction of raw materials, including steel, due to the increase generated by the globalization and development of the demand of societies. This is why the present research evaluated Nopal (opuntia ficus indica) as a natural corrosion inhibitor. The particulate material was added in different concentrations (0.0%, 0.1%, 0.5%, 1.0% and 2.0%) by weight in aqueous solution, attacking commercial samples of AISI 1020 steel, then electrochemical measurements of linear polarization resistance (LPR), Tafel polarization curves and half-cell potential were carried out. The results showed that Nopal in concentrations of 1% and 2% reduces the amount of mass, along with the intensity and speed of corrosion up to 30% and 40% respectively, so that the nopal has a remarkable inhibitory power of corrosion, which allows improving the durability in structural steels.
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Topic: SI - Structural Integrity
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INFLUENCE OF NOPAL (OPUNTIA FICUS-INDICA) ON HYDRATION PHENOMENA AND SETTING TIMES OF COLOMBIAN COMMERCIAL CEMENT.
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HERNÁNDEZ CARRILLO CARLOS GABRIEL 1, GUTIERREZ JUNCO OSCAR JAVIER 2, PINEDA TRIANA YANETH 3,
1 Universidad Pedagógica y Tecnológica de Colombia , 2 Universidad Pdagógica y Tecnológica de Colombia, 3 Universidad Pedagógica y Tecnológica de Colombia,
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Email: yaneth.pineda@uptc.edu.co
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Abstract: El cemento hidráulico es un conglomerante inorgánico de origen calcáreo, utilizado para la construcción de obras de ingeniería civil. Asimismo, es considerado el material manufacturado de mayor producción en el mundo. Sus propiedades se conciben en función de sus componentes, los cuales brindan características mecánicas adecuadas para la construcción. Sin embargo, pese a la contribución de estos materiales al desarrollo humano en la modernidad, su producción consume grandes cantidades de materias primas vírgenes, recursos energéticos y genera gases de efecto invernadero. Por consiguiente, se emplean elementos cuya inclusión modifica sus propiedades fisicoquímicas para diversas aplicaciones. No obstante, se desconoce las ventajas en costos, producción e impacto ambiental sostenible de esto materiales. Por lo anterior, la presente investigación evaluó el efecto del Nopal pulverizado como aditivo en mezcla de cemento comerciale de uso general, caracterizado y controlado mediante caracterización micro estructural por Difracción de rayos X y composición química. Posteriormente su efecto en los procesos de hidratación en mezclas con relación agua/cemento de 0,27, mediante un calorímetro semi-adiabático, al adicionar Nopal en proporciones del 1%, 2%, 5%, un aditivo comercial y su comparación con una muestra de control (0% de Nopal), previamente caracterizada la especie vegetal y controlada su composición y estructura. Los resultados exponen cambios en el calor de hidratación y efectos retardante en los procesos exotérmicos tradicionales al adicionar Nopal en los cementos en cantidades de 1% que producen un efecto similar el aditivo retardante comercial sin cambios en la resistencia mecánica. Estos fenómenos físico químicos se han relacionado con los cambios en las fases cristalinas resultantes de la composición del cemento, lo que permitió formular un análisis cuantitativo de los resultados obtenidos. Igualmente, estos permiten proyectar nuevas investigaciones relacionadas con establecer los cambios a tiempos posteriores a los tiempos de fraguado evaluados, junto con la determinación del Nopal como propuesta de aditivo comercial.
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Topic: SM - Surface Modification (Ion Implantation, Ion Nitriding, Magnetron Sputtering, Cathodic Arc, Sol-Gel, Thermal Spray)
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BACTERICIDAL SURFACE TREATMENTS FOR DENTAL IMPLANTS BASED ON SILVER AND COPPER ION CO-IMPLANTATION
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CARO PRADOS JAIME 1, BONET MONTSERRAT RAÜL 2, ORRIT-PRAT JORDI 3, MUÑOZ VILLANUEVA JOAN 4,
1 FUNDACIÓ EURECAT, 2 FUNDACIÓ EURECAT, 3 FUNDACIO EURECAT, 4 MICRODENT IMPLANT SYSTEM S.L.,
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Email: joan@microdentsystem.com
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Abstract: In the field of dental implantology, the widespread use of dental implants has been one of the most important changes and advances in dental practice in recent years. However, in spite of the predictability of dental implant treatments, which show success rates of around 90% after 10 years of insertion, there are still important problems to overcome, with a group of pathologies that cause the loss of peri-implant bone and, finally, the loss of the implant. In particular, infection caused by bacterial colonization (peri-implantitis) is one of the main causes of implant failure. Among the different approaches proposed to solve this problem, the surface treatment of implants by incorporating bactericidal metal ions (Cu, Ag, Zn) has been studied. Silver is by far the most effective biocidal metal element, acting on a broad spectrum of bacteria (both gram-negative and gram-positive), showing a low tendency to develop bacterial resistance, and inhibiting polymicrobial colonization. Its bactericidal efficacy has been demonstrated against pathogens commonly found in peri-implantitis: S. mutans, S. aureus, S. oralis, P. gingivalis and A. actinomycetemcomitans. Moreover, since ancient times, copper ion has been recognized as a potent bactericidal agent agaisnt a wide range of bacteria, fungi and viruses.
On the basis of the foregoing, in this work, bactericidal surface treatments on titanium grade 4 have been developed by means of silver and copper ion co-implantation using a Metal Vapor Vacuum Arc (MEVVA) ion source. Morphology, structure and silver/copper concentration depth profile were characterized by SEM and XPS as a function of ion implantation voltage and dose. Mechanical properties were analyzed by means of nanoindentation. Cytotoxicity was studied using mammal fibroblasts BALB/3T3. The antibacterial activity against S. aureus and E. coli, and the resistance to the formation of a biofilm composed of the bacteria F. nucleatum, P. gingivalis and A. actimomycetemcomitans was analyzed.
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Topic: SM - Surface Modification (Ion Implantation, Ion Nitriding, Magnetron Sputtering, Cathodic Arc, Sol-Gel, Thermal Spray)
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EMERGING BISMUTH-BASED PHOTOCATALYSTS AND THEIR THERMAL SPRAY PROCESSING FOR HETEROJUNCTION COUPLING IN A TOP-DOWN APPROACH
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MUÑOZ-SALDAÑA JUAN 1, GUTIÉRREZ PÉREZ AIXA IBETH 2, ROSALES ANDRADE IVAN DANIEL 3, AYALA AYALA MARÍA TERESA 4, PÉREZ BEDOLLA JHON SEBASTIAN 5, BENITEZ CASTRO ANGELICA MARÍA 6,
1 Centro de Investigación y de Estudios Avanzados del IPN, 2 Cinvestav, 3 Cinvestav, 4 Cinvestav, 5 Cinvestav, 6 Cinvestav,
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Email: angelica.benitez@cinvestav.mx
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Abstract: Photocatalysis has become important in the development of sustainable technologies for environmental remediation and energy conversion. The design of a photocatalyst that can efficiently utilize visible light without the drawback of increased recombination is a critical challenge. Bismuth-based compounds have recently been recognized as the basis for multifunctional ceramics with applications in environmental remediation, alternative clean piezoelectric power, smart materials and biomedicine. Particularly, visible light photoactive (NaxK1-x)1/2Bi1/2TiO3 (NKBT) heterojunctions have demonstrated their applicability in environmental remediation. In this work, piezoelectric powders of Bismuth-based perovskite (NaxK1-x)1/2Bi1/2TiO3 (NKBT100x), where x = 1, 0.8 and 0.6, were synthesized by ball milling and solid-state reaction. The results of physical, chemical and photocatalytic properties of NBT and NKBT 60 based powders/coatings are reported. In experiments spraying powders in a mixture of NKBT 60 and Bismuth (Bi) metal powders in a 50/50 vol:vol ratio and, collected in a staged powder reactor, their structural, microstructural and optical characteristics were obtained, as well as their effect on the photocatalytic activity in two model reactions: photodegradation of rhodamine B (irradiation and photooxidation of methanol in formaldehyde, both under sunlight). According to the structural and chemical analysis, flame spraying is an advantageous method that allows growing NBKT - bismuth titanates - titanium oxides (anatase and/or rutile) - bet-Bi2O3 - Bi heterojunctions from NBKT/Bi mixtures in a top-down approach. Variations in phase content in the heterojunction can be adjusted by collecting the powders at different stages of the powder reactor. Further characterizations showed that the obtained powders exhibit raspberry-like morphology and nanostructured active surfaces as well as reduced visible light forbidden band energies. The multiphase heterojunction powder of beta -Bi2O3 - NKBT40 - Bi4Ti3O12 - Bi12TiO20 - anatase - Bi presented the highest photocatalytic performance. The reaction rate constant, kRhB and kMetOH were calculated to be 33.45 x 10-3 min-1 and 0.25 x 10-6 min-1, respectively, making this material more photoactive than those used commercially and suitable for these reactions. NBT microspheres were also deposited by oxyacetylene flame spraying. The physicochemical properties were analyzed as a function of the spray parameters: fuel/oxygen ratio (F/O), standoff distance (SOD) and total gas flow (TF). A flame with reducing characteristics promotes the formation of TiO2 (anatase and rutile) and Bi4Ti3O12, while an oxidizing flame results in coatings rich in NBT and Bi4Ti3O12. The SOD mainly influences the degree of crystallinity, which is higher at shorter distances. Optical properties estimated by UV-VIS diffuse reflectance confirmed an increase in light absorption after the FS process, with an Eg redshift from 3.32 eV of the NBT powder to 2.63-2.96 eV of the coatings. These values are F/O dependent, with a significant narrowing of Eg under reducing conditions. Photoelectrochemical measurements revealed that faster electron uptake is obtained due to the transformations occurring throughout the FS process, while retaining almost 70% and 88% of the photocurrent density (jph) at UV and visible light, respectively. These results suggest the great potential of the FS methodology to produce multiphase photocatalytic coatings by tuning the processing parameters.
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Topic: SM - Surface Modification (Ion Implantation, Ion Nitriding, Magnetron Sputtering, Cathodic Arc, Sol-Gel, Thermal Spray)
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MICROSTRUCTURE AND MECHANICAL PROPERTIES OF OXYNITRIDED TI-6AL-4V WATER COLLECTED IN-FLIGHT PARTICLES FROM TWIN WIRE ARC SPRAYING
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MUÑOZ-SALDAÑA JUAN 1, NANGO BLANCO MAURICIO 2, SÁNCHEZ TOVAR JOSÉ GUADALUPE 3,
1 Centro de Investigación y de Estudios Avanzados del IPN, 2 CINVESTAV, 3 Centro de Investigación y de Estudios Avanzados del IPN,
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Email: jose.sanchezt@cinvestav.mx
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Abstract: The mechanism of solidification and the reaction of Ti-6Al-4V particles in flight with the surrounding atmosphere and during the formation of coatings deposited by twin wire arc spraying (TWAS) is complex, and there are no previous reports in the literature. This work studies the microstructure, chemical composition, and mechanical properties of Ti-6Al-4V in-flight particles melted and atomized by TWAS using nitrogen as a carrier gas. The particles were collected in water at two stand-off distances (SOD) (25 and 125 mm). XRD identified phases, and their chemical compositions were quantified by WDS analysis. Mechanical properties (hardness, H, and reduced elastic modulus, Er) were determined by nanoindentation using a sphere-conical diamond tip. The in-flight particles show the presence of a-Ti, b-Ti, TiN, and TiO2 phases. SEM observed an equiaxial and columnar dendritic microstructure on the surface and cross-section of the particles for both SOD and mainly two phases were quantified: (Ti,V,Al)Ox and (Ti,V)Nx corresponding to the dendritic and interdendritic regions, respectively. The average values (H, Er) in the (Ti,V,Al)Ox and (Ti, V)Nx phases were (21.2, 250), (15.9, 208) GPa and (21.6, 249), (18.4, 206) GPa for 25 and 125 mm, respectively; which are significantly higher than that of the raw material (4.9, 210) GPa. The increase in hardness at higher SOD is due to higher nitriding by increasing the residence time of the particles as these interact with the carrier gas during their flight. TWAS is a technique with high potential for developing oxynitrided coatings with improved mechanical properties for various applications.
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Topic: SM - Surface Modification (Ion Implantation, Ion Nitriding, Magnetron Sputtering, Cathodic Arc, Sol-Gel, Thermal Spray)
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PLASMA-ASSISTED NITRIDING OF M2 STEEL BY THE AEGD TECHNIQUE AND CHARACTERIZATION OF BASE AND NITRIDED MATERIAL FOR DIFFERENT TIMES OF THE NITRIDING PROCESS
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MARTINEZ GARCIA SEBASTIAN 1, GONZALEZ CARMONA JUAN MANUEL 2, RUDEN MUÑOZ ALEXANDER 3,
1 Universidad Tecnologica de Pereira, 2 Centro de Ingeniería y Desarrollo Industrial , 3 Universidad Tecnologica de Pereira,
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Email: arudenm@utp.edu.co
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Abstract: M2 steel as a material used in different applications in industrial fields, since it presents interesting mechanical properties in terms of its surface hardness, resistance to fatigue and corrosion, which can be improved through surface treatments such as nitriding, for that matter. punctually, the study of its mechanical properties after its plasma nitriding assisted by the AEGD technique is proposed, where in turn it is intended to establish the change in its mechanical properties, particularly the surface hardness, by making variations in the duration of the nitriding process. . In addition to the above, during the development, it is intended to evaluate the influence of the parameters associated with the plasma during the nitriding process, through non-invasive techniques such as Optical Emission Spectroscopy (OES) and with the implementation of a probe of langmuir. In turn, different characterization techniques will be implemented such as X-ray Diffraction (XRD, Scanning Electron Microscopy (SEM), Energy Dispersed Spectroscopy (EDS), Static Scratch, tribology, the above in order to determine additional variations in the M2 steel.
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Topic: SM - Surface Modification (Ion Implantation, Ion Nitriding, Magnetron Sputtering, Cathodic Arc, Sol-Gel, Thermal Spray)
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STUDY OF THE ADVANCES AND APLICATIONS OF CONVENTIONAL FLAME SPRAY IN THE LAST DECADE
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ALVAREZ FLOREZ DARWIN REYNALDO 1, BECERRA ABRIL GERARDO 2, GIANNINI DELGADO RENATO 3, RAMOS HINOJOSA RODRIGO 4,
1 Universidad catolica de santa maria, 2 universidad catolica de santa maria, 3 Universidad Catolica de Santa Maria , 4 Universidad Católica de Santa María,
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Email: 71225922@ucsm.edu.pe
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Abstract: Despite technological advances in the area of thermal spraying concerning new coating techniques, conventional spraying through flame is still widely used in the industry this because sometimes it is usually the best option to coat surfaces, either because it has the least cost of implementation in equipment, because it is the most commercial or because of the mechanical benefits that it has as an advantage due to its relatively low working temperatures. In this work, you can see this technique's current applications in the mining industry and biomedical, among others. As well as technical studies that deal with this technique on issues of mechanical properties or microstructural properties product of flame spraying, and it is evident that, despite the new spraying techniques, the flame spraying technique through oxy-combustion justifies its current use in the industry, evidenced by more than 80 articles published in recent years.
We can relate the interest in applying CFS compared to other techniques due to the ease of the process. Since it is the least complicated of all the processes, it is also a more accessible technique due to the equipment that the technique requires, which are usually less expensive. Compared to other thermal spray techniques. Recent studies that focus on improving the spraying process of this technique suggest that we are reaching "perfection", which is logical given the time it has been in service in the industry.
Regarding properties that can be achieved with conventional thermal spraying by flame in applications where corrosion-resistant coatings are required, and materials such as tungsten carbide, chromium, and aluminum compounds are used. Porosity is an important characteristic in the conventional thermal flame spraying process, as it can affect thermal conductivity, corrosion resistance, and hardness. In coatings that seek to minimize residual stresses, several factors, such as impact velocity, preheat temperature, and materials' behavior, must be considered, and appropriate annealing must be performed to minimize energy differences. According to studies, conventional thermal flame spraying is, on average, 60-70% more corrosion-resistant in anticorrosive applications.
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Topic: TFN - Thin Films and Nanomaterials
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COMPOSITE MAGNETIC SKYRMION SYSTEMS IN ASYMMETRIC BILAYERS
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PINA VELASQUEZ JUAN CARLOS 1, DE SOUZA SILVA CLÉCIO CLEMENTE 2,
1 UNIVERSIDADE FEDERAL DE PERNAMBUCO, 2 UNIVERSIDADE FEDERAL DE PERNAMBUCO,
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Email: clecio.cssilva@ufpe.br
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Abstract: Skyrmions are topologically protected nanoscopic magnetic textures appearing in chiral magnetic materials under appropriate conditions. Their small size and the fact that they can be driven by very small spin-polarized currents, thus inducing low dissipation, make them promising candidates for future applications in high density magnetic storage and spintronics. However, once in motion, skyrmions are also subjected to a Magnus force, which produces a lateral motion forcing the skyrmion to eventually annihilate at the wall of, e.g., a racetrack, thus never reaching the intended destiny. This oblique motion, known as the skyrmion Hall effect (SHE), has a characteristic Hall angle, which depends on microscopic parameters of the system, and a Hall sign, which depends on the topological charge of the skyrmion. Recently, it has been shown that the SHE can be eliminated in a bilayer system comprising two ferromagnetic layers coupled antiferromagnetically. In such system, identical skyrmions, but with opposite topological charge, can be created in each layer. These skyrmions attract each other and form a pair with null total topological charge, which potentially eliminates the unwanted SHE. However, the success of this idea in promoting fully longitudinal motion of skyrmions relies on a highly symmetrical configuration of the magnetic parameters of both layers. In the present work, we perform a comprehensive theoretical investigation of coupled skyrmion pairs in non-symmetric bilayers. We introduce asymmetry in the Dzyaloshinskii-Moriya interaction (DMI) coefficients in the top and bottom layers and calculate, using micromagnetic simulations and semi-analytic methods, how the skyrmion-skyrmion coupling energy and the skyrmion radii evolve with increasing asymmetry. We also investigate the evolution of the Hall angle of the coupled pair as a function of the antiferromagnetic coupling between the top and bottom layers and the ratio between their DMI coefficients.
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Topic: TFN - Thin Films and Nanomaterials
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EFFECT OF GRAPHENE OXIDE MAGNETIC NANOFLUIDS ON IMPROVED OIL RECOVERY
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GUTIÉRREZ NIÑO NELSON 1, PÉREZ RODRIGUEZ ELCY MARIANA 2, CABANZO HERNÁNDEZ RAFAEL 3, SANTOS SANTOS NICOLAS 4, MEJÍA OSPINO ENRIQUE 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 UIS, 5 Universidad Industrial de Santander,
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Email: emejia@uis.edu.co
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Abstract: Heavy and extra-heavy crude oils are unconventional hydrocarbons containing a complex mixture of organic compounds, such as saturated hydrocarbons, aromatics, resins and asphaltenes. These crudes have a higher density and viscosity than conventional crudes and their chemical composition varies depending on the place of origin. In the extraction process, the viscosity and density of heavy and extra-heavy crude oils present a significant challenge, as they can clog reservoir pores and make it difficult for oil to flow to production wells. Additionally, extracting these crudes may require the use of enhanced recovery techniques such as steam injection or hydraulic fracturing, increasing costs and environmental challenges.
In terms of transportation, heavy and extra-heavy crude oils have low fluidity and high viscosity, making them difficult to pump through pipelines and storage tanks. To improve their fluidity and facilitate transportation, these crudes may require the use of diluents or additives. In addition, the high wettability of some rock-fluid systems towards oil aggravates this situation. This phenomenon refers to the tendency of reservoir rocks to prefer oil over water. The high wettability of oil in the rocks reduces the flow of oil through the reservoir pores and pipelines, which decreases the recovery factor and increases operating costs.
Despite the challenges, heavy and extra-heavy crude oils are an important source of hydrocarbons, and their exploitation may be economically viable in certain circumstances. However, it is also important to consider the environmental and social impacts associated with its extraction and transport, and to search ways to minimize these impacts through more sustainable practices and more advanced technologies.
Considering the above, various techniques have been developed to improve the exploitation of heavy and extra-heavy crude oil. These techniques are based on the modification of the oil and/or the environment where it is found, by means of physical or chemical agents. One of the most recent and promising methods is the use of nanotechnology to create nanofluids that can improve the properties of heavy crude oil and make it easier to exploit. Nanofluids are colloidal suspensions containing nanoparticles of materials with unique magnetic, optical, rheological, or thermal properties, in a liquid medium. These nanomaterials can modify the properties of heavy crude oil and the environment in which it is found, to make it easier to extract and transport.
In this sense, in the present investigation, aqueous nanofluids were synthesized from magnetite nanoparticles supported on graphene oxide (Fe3 O4@GO), and their obtaining was determined by various characterization techniques such as DRX, SEM, FTIR DLS and UV- Vis. Subsequently, its effect on the interfacial tension of the oil was evaluated, finding a significant decrease depending on the concentration of the nanofluid. Likewise, a wettability alteration test was carried out on an outcrop rock sample with an affinity to be wetted by oil, in which it was established that, after its immersion in nanofluids with different concentrations of Fe3O4@GO for a period of three hours, there was a decrease in its wettability to oil reflected in an increase in the value of the contact angle.
The results obtained from this study indicate that the use of composite nanofluids significantly improves the reservoir conditions for crude oil exploitation, which could result into an increase in the recovery factor.
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Topic: TFN - Thin Films and Nanomaterials
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EFFECT OF ORGANIC THIN FILMS MORPHOLOGY AND LIGHT-EMITTING LAYER THICKNESS ON THE OPTO-ELECTRIC PROPERTIES IN AN OLED
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MENDEZ MERCHAN GERMAN ANIBAL 1, ARDILA VARGAS ANGEL MIGUEL 2, BURGOS CASTRO VALERIA 3,
1 Universidad Católica de Colombia, 2 Universidad Nacional de Colombia, 3 Universidad Nacional de Colombia,
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Email: vburgosc@unal.edu.co
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Abstract: Organic Light Emitting Diodes (OLEDs) are becoming the emerging technology for high-quality displays and solid-state lighting, due to various properties of organic materials that make them more appropriate in the manufacture of optoelectronic devices, such as their flexibility, color quality, and high efficiency and therefore energy saving. Using the high vacuum thermal evaporation technique, thin films of the organic semiconductor compounds NPB (used as hole transporter), CBP:Ir(ppy)2(acac) (used as phosphorescent emitter) and TPBi (used as electron transporter), were fabricated and morphologically characterized in order to determine the best preparation conditions for using these layers in the implementation of an organic light-emitting device. For this study, the deposition temperature of the different layers was varied, keeping the deposition rate constant in accordance with previous studies. The surface morphology of these samples was analyzed by atomic force microscopy (AFM), to obtain roughness values to determine the best deposit conditions. This study allowed us to define that the layers deposited at 22°C present lower roughness values, compared to those deposited at higher temperatures. Subsequently, under this parameter, green light emitting devices were fabricated with the ITO/NPB/CPB:Ir(ppy)2(acac)/TPBi/Al architecture, varying the thickness of the emitting layer at 15nm, 20nm, and 25nm. The electrical properties of the device were determined by means of the current/voltage curve and the optical ones by means of the electroluminescence spectrum. The results indicate that the device with an emitting layer thickness of 15nm is the one that presents the best-emitting properties.
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Topic: TFN - Thin Films and Nanomaterials
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NI AND ZN-DOPED YBCO NANOWIRES PRODUCED BY THE SOLUTION BLOW SPINNING TECHNIQUE.
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JUNIOR MILTON BATISTA FERREIRA 1, CHAVES DAVI ARAUJO DALBUQUERQUE 2, MOTTA MAYCON 3, ORTIZ WILSON AIRES 4, ZADOROSNY RAFAEL 5,
1 Universidade Estadual Paulista (UNESP), Faculdade de Engenharia, Ilha Solteira, São Paulo, Brazil, 2 Universidade Federal de São Carlos, UFSCar, 3 Universidade Federal de São Carlos, UFSCar, 4 Universidade Federal de São Carlos, UFSCar, 5 Universidade Estadual Paulista (UNESP), Faculdade de Engenharia, Ilha Solteira, São Paulo, Brazil,
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Email: rafael.zadorosny@unesp.br
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Abstract: To investigate the effects of magnetic (Ni) and non-magnetic (Zn) doping on the YBa2Cu3O(7-x) (Y123) superconductor, fibers of the material were produced using the Solution Blow-Spinning (SBS) technique. This technique is advantageous over other methods for producing materials on a small scale, mainly due to the high productivity rate. Therefore, the precursor solution to be fibered must have an optimal viscosity for the technique to be effective. In this sense, polyvinyl(pyrrolidone) [PVP] is a stabilizing polymer in the synthesis of metallic materials and gives the solution levels of viscosity that can be controlled by the polymer concentration in the solution or by its molar mass. Thus, YBa2Cu(3-n)Xn solutions were prepared, where X = Ni or Zn and n = 0.01; 0.02 and 0.04, using metallic acetates and solvents (methanol, propionic acid, and acetic acid). After being blown in SBS, the fibers were collected in a non-woven fabric, and thermal treatments were carried out for calcination and sintering. SEM characterizations show a decreasing average fiber diameter after the heat treatment for small than 500 nm. XRD shows that the PVP molar mass does not interfere with the material's phase formation, and all samples showed the BaCuO secondary phase. Furthermore, the doping elements were not identified in the X-ray characterization, suggesting that they may have entered the material's composition. From the Rietveld refinement, the Y123 and BaCuO phases are confirmed, and apparently, there is a change in the unit cell volume for samples with higher concentrations of dopants. However, these conclusions will be confirmed, for example, by magnetically characterizing the samples.
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Topic: TFN - Thin Films and Nanomaterials
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OBTAINING LAYERS OF TITANIUM OXIDE ON THE SURFACE OF A TITANIUM SUBSTRATE.
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BARBA ORTEGA JOSE JOSE 1, PARIS ELAINE CRISTINA 2, RINCÓN JOYA MIRYAM 3,
1 Universidad Nacional de Colombia, 2 Embrapa, 3 Universidad Nacional de Colombia,
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Email: mrinconj@unal.edu.co
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Abstract: In this study, we have focused on obtaining titanium oxide layers on the surface of a titanium substrate. TiO2 obtained through anodizing possesses several distinctive properties when compared to conventional TiO2. The use of different electrolytes and current parameters during anodization leads to the formation of porous structures, resulting in an increased surface area, making it an excellent photocatalyst. Furthermore, TiO2 obtained through anodizing exhibits unique optical properties owing to its porous structure. From a mechanical perspective, the porous structure helps to enhance the adhesion to the substrate, as well as increasing the corrosion resistance of the substrate. Overall, TiO2 obtained through anodizing is a highly promising material with a wide range of applications, such as catalysts, sensors, optoelectronic devices, and protection against corrosion.
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Topic: TFN - Thin Films and Nanomaterials
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PRODUCTION OF IRON OXIDE-BASED NANOHETEROSTRUCTURES FOR APPLICATIONS IN MAGNETIC HYPERTHERMIA THERAPY.
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CORREDOR FIGUEROA ADRIANA PATRICIA 1, MORALES ANGIE NATALY 2, OLARTE OMAR 3, GARCÍA LEONARDO 4, CADAVID DORIS 5,
1 Universidad ECCI, 2 National University of Colombia, 3 Universidad Nacional de Colombia, 4 Universidad ECCI, 5 Universidad Nacional de Colombia,
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Email: dycadavidr@unal.edu.co
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Abstract: It is estimated that in the year 2020 about 10 million people worldwide will die of cancer. It is therefore important to find alternative non-invasive treatments that can counteract this disease. Currently, magnetic hyperthermia is a promising treatment as an adjuvant to eliminate cancer cells. In fact, the possibility has been studied that the nanoparticles used in the therapy, are nanoheterostructured materials, that is, nanomaterials made up of multiple components such as gold (Au), cobalt (Co), manganese (Mn), zinc (Zn) and silver (Ag) among others, in order to obtain greater efficiency in the elimination of cancer cells. In this work, the synthesis of nanoheterostructures (NHs) based on iron oxide and metals such as Zn, Mn and Ag was carried out by the thermal decomposition method. The material characterization was carried out by X-ray diffraction (XRD), transmission electron microscopy (TEM) and magnetization measurements. Monodisperse NHs were obtained, with cubic morphology, with an average size of 30 nm, which proved to increase in temperature by more than 10°C when subjected to an alternating magnetic field.
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Topic: TFN - Thin Films and Nanomaterials
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SIMULATION OF THE ABSORBER LAYER THICKNESS VARIATION IN SNS SOLAR CELLS USING MATLAB
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RONDÓN ALMEYDA CARLOS EDUARDO 1, ROJAS RINCÓN CLARA LIZETH 2, SEPÚLVEDA ALEXANDER 3, BOTERO LONDOÑO MÓNICA ANDREA 4, MANTILLA VILLALOBOS MARÍA ALEJANDRA 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad Industrial de Santander, 4 Universidad Industrial de Santander, 5 Universidad Industrial de Santander,
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Email: marialem@uis.edu.co
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Abstract: The study of thin-film solar cells based on SnS is becoming increasingly relevant due to its advantages over similar technologies, such as its low cost, toxicity, and the fact that its constituent elements are more abundant in the earth's crust. On the other hand, Simulations allow modelling of the behaviour of solar cells to understand the processes and improve the device's efficiency. Therefore, in this work, the simulation of a heterojunction with SnS/ZnS/ZnO configuration is carried out using mathematical models that represent the physical behaviour of the solar cell. Two radiation models were evaluated, one using a theoretical equation and the other with data from the incident radiation in Bucaramanga. The simulation was performed using MATLAB. The optimal thickness of the absorbent layer was established from the results obtained for open circuit potential (Voc), short circuit current (Jcs) and fill factor.
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Topic: TFN - Thin Films and Nanomaterials
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SYNTHESIS AND CHARACTERIZATION OF MAGNETIC GRAPHENE OXIDE (GO@FE 3 O 4 ): NANOMATERIAL WITH POTENTIAL APPLICATIONS TO REDUCE THE VISCOSITY OF HEAVY OIL.
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PÉREZ RODRIGUEZ ELCY MARIANA 1, GUTIÉRREZ NIÑO NELSON 2, SANTOS SANTOS NICOLAS 3, CABANZO HERNANDEZ RAFAEL 4, MEJÍA OSPINO ENRIQUE 5,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 UIS, 4 UIS, 5 Universidad Industrial de Santander,
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Email: emejia@uis.edu.co
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Abstract: In one of its branches, nanotechnology studies the design of nanometer-sized materials
which possess chemical and physical properties different from those of macroscopic
material; when talking about magnetic particles the decrease in size brings a change in the
magnetic behavior of the material, magnetite (Fe 3 O 4 ) is currently one of the most studied
magnetic nanoparticles; this type stands out for its low cost, its low coercive field, its ease
of surface modification and its good magnetization levels (Du., Liu & Xia.,2016).
The addition of magnetite nanoparticles has been applied in many fields, including
construction with the use of magnetite as a load-bearing material increasing the weight of
concrete, in medicine creating barriers to the propagation of radioactive emissions and has
been considered in the hydrocarbon industry as an improved recovery option since
magnetic nanoparticles can selectively adsorb asphaltenes and facilitate the breakage to
single bonds (Nassar, Hassan., & Pereira-Almao., 2011) reducing the viscosity of the crude
oil which allows it to flow between the rock without resistance; however, magnetite
nanoparticles tend to form agglomerates due to strong anisotropic dipolar interactions, thus
losing their dispersibility in aqueous media, which hinders their use in this field; this is why
it becomes essential to immobilize these nanoparticles on supports to preserve their
properties (Deng., Wen & Wang., 2012). Among a large group of materials, graphene and
its derivatives are considered to have a high capacity for the immobilization of
nanoparticles since graphene oxide (GO) has a lamellar structure that grants it a large
surface area and high reactivity of its functional groups; GO-immobilized nanoparticles not
only prevent aggregation, but also preserve the properties of nanoparticles through a
synergistic effect between both components (Gómez., Cabanzo & Mejía-Ospino., 2019).
In this study, the synthesis of graphene oxide was carried out by the modified Hummers
method, then ferromagnetic nanoparticles were added by a bottom-up route, later washes
were performed to purify the material and it was freeze-dried in order to obtain a powder
for characterization. The material was spectroscopically characterized by FT-IR which is a
technique that provides structural information showing bands associated with GO and
magnetite, additionally scanning electron microscopy was performed which is a
microscopic technique that shows specific characteristics of the surface morphology and
size of the material where a change in morphology is observed due to the presence of a new
material on the surface of the GO film, this new material is magnetite evidenced by means
of a punctual EDS study and finally a thermogravimetric analysis as a complementary
technique to determine the thermal behavior of the material where a degradation peak was
obtained at 685ºC approximately, additionally, by exposing the material to a constant
magnetic field its magnetization was corroborated due to the strong attraction it
experienced towards the source of the field. Finally, this study was able to obtain a
magnetic graphene oxide nanomaterial characterized by different techniques and presents it
as a candidate for possible applications as a viscosity reducer of a heavy crude oil.
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Topic: TFN - Thin Films and Nanomaterials
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VORTEX STATE IN A TWO-BAND MESOSCOPIC SUPERCONDUCTOR/FERROMAGNETIC HYBRID SYSTEM
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PINA VELASQUEZ JUAN CARLOS 1,
1 UNIVERSIDADE FEDERAL DE PERNAMBUCO,
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Email: juan.carlos@ufpe.br
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Abstract: We consider a two-band supercondutor-ferromagnetic hybrid system by using the two-component Ginzburg-Landau model. In this system is possible to obtain diferent vortex configuration for each band, the so-called fractional vortex state. In this work we study the effect of the homogeneuous magnetic field and the permanent magnetization of the ferromagnetic on the stability of fractional vortex state and the formation of vortex-antivortex pair and found that the permanent magnetization of the ferromagnetic favors to spontaneously access some fractional vortex state. Finally, we build up a phase diagram in the magnetic field-permanent magnetization plane for fractional vortex and vortex-antivortex states.
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Topic: WCO - Wear and Corrosion/Oxidation
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CHARACTERIZACIÓN OF MATERIALS TO DEVELOP CORROSION SENSORS TO BUILDING INDUSTRY
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TORRES RAMIREZ JHON EDISSON 1,
1 CNEA,
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Email: jtorram@gmail.com
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Abstract: This research work is a first step in the development of a simple, versatile and economical sensor to be embedded in reinforced concrete structures to determine the corrosion rate of reinforcing steel. The feasibility of using galvanic couple current monitoring as a method to sense and assess the level of rebar corrosion was investigated. To this purpose, the electrochemical behavior of four candidate metals to build the sensor (SAE 1040 carbon steel, copper, AISI 304 stainless steel and titanium) embedded in mortar and exposed to different environmental conditions was characterized. Three proposed galvanic couples (carbon steel/stainless steel, carbon steel/copper and carbon steel/titanium), as well as carbon steel bars (of the same type of those used as reinforcements) were embedded in mortar specimens. The objective was to find out a correlation between the current of the galvanic couples and the real corrosion rate of the rebars in a broad range of environmental conditions. It was found that copper and titanium showed good resistance to localized corrosion, being excellent candidates to be used in highly corrosive environments, particularly in the presence of chlorides. However, from the electrochemical characterization, it became evident that the metal generating the greatest galvanic currents when coupled with the carbon steel was cooper. Furthermore, the measurement of the galvanic current showed the importance of the anodic/cathodic area ratio relationship. It was found that when the anode/cathode area ratio was 1:7, a correlation between the galvanic current of the carbon steel/copper couple and the corrosion current of the carbon steel could be established. As a conclusion, among the three galvanic couples proposed, the carbon steel/copper one seems to be the most promising one to build a sensor.
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Topic: WCO - Wear and Corrosion/Oxidation
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CHARACTERIZATION OF THERMAL FILMS FORMED BETWEEN 100°C TO 400°C ON ASTM A-213 T91 (FE-9CR-1MO) STEEL IN ATMOSPHERES: H2S-N2-O2 AND AIR.
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BEDOYA MORENO MARIA ISABEL 1, ESTUPIÑAN DURAN HUGO ARMANDO 2,
1 Universidad Nacional de Colombia, 2 Universidad Nacional de Colombia,
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Email: haestupinand@unal.edu.co
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Abstract: ASTM A-213 T91 (Fe-9Cr-1Mo) steel is known in its applications for being resistant to high temperatures and resistant to gases, highly oxidizing, carburizing and sulfiding agents. Its use in the construction of catalytic conversion units in heavy crude oil still generates uncertainty, given the high demands on the formation of highly stable protective layers in the operating temperature ranges.
Ferritic steels have been selected for use in the construction of crude refining units with thermocatalytic processes due to their adequate microstructure, their low carbon content and their balance between chromium and molybdenum content. The importance of these factors, both microstructural and compositional, which added to the enrichment of chemical elements from the gases produced from CO2 and H2S and from the heavy crude oil itself, is greatly reflected in the quality of the protective layers formed that serve as a barrier. both thermal and physicochemical in an environment of highly aggressive atmospheres.
This paper analyzes the characterization results of layers formed on an ASTM A-213 T91 (Fe-9Cr-1Mo) steel in atmospheres: H2S-N2-O2 and air between 100°C and 400°C. Atomic force microscopy techniques in mechanical and electrical modes, Confocal Raman Spectroscopy, Raman thermometry, Scanning Electron Microscopy and Energy Dispersive X-rays, were used to compare and discuss the obtained results. The characterization focused on analyzing the layers formed on this steel based on its structural stability.
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Topic: WCO - Wear and Corrosion/Oxidation
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CHEMICAL SPECIES FORMED ON THE SURFACE OF BORIDED AISI 316L UNDER WET SLIDING WEAR
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MARTINEZ TRINIDAD JOSE 1, GARCIA RICARDO 2, FLOREZ EDER 3,
1 Instituto Politécnico Nacional , 2 Universidad Francisco de Paula Santander Ocaña, 3 UFPSO,
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Email: enflorez@ufpso.edu.co
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Abstract: In this work, the evolution of the chemical species formed on the surface of the borided and non-borided AISI 316L steels during wet sliding conditions using a simulated body fluid (SBF Hanks solution) was investigated. The results revealed that the specific wear rate of the borided AISI 316L steel was ~4 times lower than that of the non-boridedAISI 316L steel under the same wet sliding conditions. Also, the corrosion and wear resistance of both steels are related to combinations of reaction productions such as B2S3,Cr2O3, and Fe2O3 during sliding wear by the formation of the passive layer, according to the results obtained by XPS.
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Topic: WCO - Wear and Corrosion/Oxidation
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COMPARATIVE ANALYSIS OF THERMAL FILMS FORMED BETWEEN 100°C TO 400°C ON ASTM A-213 T92 STEEL (FE-9CR-0.5MO) IN ATMOSPHERES: H2S-N2-O2 AND AIR.
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BEDOYA MORENO MARIA ISABEL 1, ESTUPIÑAN DURAN HUGO ARMANDO 2,
1 Universidad Nacional de Colombia, 2 Universidad Nacional de Colombia,
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Email: haestupinand@unal.edu.co
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Abstract: Steels resistant to high temperatures are being used in the construction of catalytic conversion units for heavy crude oils with highly oxidizing, sulfiding and fueling environments.
There is currently a strong debate on the selection of steels for these applications, whether with austenitic steels or ferritic steels, the latter being conveniently selected for their adequate microstructure, their low carbon content and their balance between chromium and molybdenum content. The importance of these factors, both microstructural and compositional, which added to the enrichment of chemical elements from the gases produced and from the heavy crude oil itself, is greatly reflected in the quality of the protective layers formed that serve as both a thermal and physicochemical barrier. in the face of a highly aggressive environment in these crude catalytic conversion units.
This paper discusses the characterization results of layers formed on an ASTM A-213 T92 (Fe-9Cr-0.5Mo) steel in atmospheres: H2S-N2-O2 and air between 100°C and 400°C. Atomic force microscopy techniques in mechanical and electrical modes, Confocal Raman Spectroscopy, Raman thermometry, Scanning Electron Microscopy and Energy Dispersive X-rays, were used to compare and discuss the obtained results. The comparisons focused on the relatively higher structural stability of the layers obtained by sulfidation than those obtained by oxidation.
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Topic: WCO - Wear and Corrosion/Oxidation
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IMPROVEMENT OF THE PHYSICOCHEMICAL PROPERTIES OF A COLOMBIAN HEAVY CRUDE UNDER THERMAL RECOVERY CONDITIONS WITH OIL-SOLUBLE CATALYSTS AND THEIR EFFECT ON THE CORROSION OF API P110 STEEL.
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SANABRIA BECERRA JULIAN ERNESTO 1, LEÓN BERMÚDEZ ADAN YOVANI 2, MOLINA VELASCO DANIEL 3, ARIZA LEÓN EMILIANO 4,
1 Universidad Industrial de Santander, 2 Universidad Industrial de Santander, 3 Universidad industrial de santander , 4 Universidad Industrial de Santander,
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Email: earizal@uis.edu.co
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Abstract: World oil reserves indicate that a high percentage corresponds to heavy and extra-heavy crudes. Therefore, in order to take advantage of these crudes, it is necessary to establish new studies and tools. There are numerous techniques to improve oil conditions, among which catalytic aquathermolysis as a recovery method plays an important role. In this investigation, the effect of three catalysts such as FeN, NiN and NMo with a concentration of 100 ppm in relation to the metal in a Colombian heavy crude oil of 12.8 °API and viscosity of 22000cp (@ 30°C) was evaluated. The tests were carried out in a batch reactor at 450psi (@ 25°C) and two temperatures of 220 and 270°C, during 66 hours of reaction.
The crudes improved by tests of density, viscosity, Maltene/Asphaltene content and their molecular structure by Nuclear Magnetic Resonance NMR-1H. The tests at 270°C showed an improvement in the physicochemical properties following the order of performance as NFe>NNi>NMo. The presence of iron naphthenate (FeN) reduced the viscosity of the crude by around 60% and the density of the oil was decreased by 3 °API units. On the other hand, the tests carried out at 220°C showed deterioration in the physicochemical properties of the improved crude, significantly increasing the viscosity, density and asphaltene content.
Additionally, the aquathermolysis tests without catalyst showed a corrosion rate on API P-110 steel in the gas phase in the range of 0.02662-0.0503 mm/y, and in the liquid phase between 0.002567-0.02979 mm/y. Meanwhile, the aquathermolysis test in the presence of FeN reduced the corrosion rate in the range of 34-50% and between 46-70% for the gas and liquid phase, respectively. The results show that the catalytic aquathermolysis method improves the physicochemical properties of the crude and the integrity of the API P-110 steel.
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