Now showing items 1-20 of 39

Aplicación de FeO, ZnO y CuO como pigmentos en compuestos cerámicos

ROA BOHÓRQUEZ, KAROL LIZETH; PAREDES ROA, RICARDO ALFONSO; LARA GONZÁLEZ, LUIS ÁNGEL; Peña Rodriguez, Gabriel (Informador TécnicoBogota , Colombia, 2019-04-12)

Entre los problemas más relevantes de la industria alfarera de Boyacá, Colombia, se encuentra la ausencia de una gama de tonalidades uniformes de sus productos finales. El color, por tratarse de una propiedad física ...
Application of maturity method to estimate compressive strength of mass concrete

Gamba Gomez, Osmar Albert; Pineda Triana, Yaneth; Peña Rodriguez, Gabriel (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

The correlation between the maturity index and the compressive strength of concrete is validated for mixtures with strengths of 2000, 2500, 3000 and 3500 PSI, which are the most used in the civil engineering field. Temperature ...
Arduino data-logger and artificial neural network to data analysis

Hector Jaime, Dulce-Moreno; Contreras Contreras, G F; Ardila Melo, R (Journal of Physics: Conference SeriesBogota , Colombia, 2019-11-29)

This work takes thermodynamic modelling through computer science for incubation process at domestic birds, that has presented energy consumption significantly high than energy used in processes. Thus, a data analysis was ...
Characterization of commercial luminescent powders

Peña Rodriguez, Gabriel; Paredes Roa, Ricardo Alfonso; Roa Bohorquez, Karol Lizeth; Castro, H F (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

Luminescent powders have attracted the attention of scientists, boosting properties as specific as mechanoluminescence, thermoluminescence, and photoluminescence among other characteristics. The uses of these properties ...
Coating of tricalcium phosphates by flame spray

Ferrer, Martha; García-Páez, Ismael H.; Rodríguez, Luis Francisco (Journal of Physics: Conference Series, 2019-11-29)

The metal alloys used for prostheses with high mechanical requirements are bioinerts, it means they have low integration with bone tissue, therefore, bioactive coatings are used in order to improve this integration. ...
Design and characterization of a magneto-dielectric composite in high frequency with aligned magnetite powders

Peña Rodriguez, Gabriel; Mancipe, D L; Pineda Triana, Yaneth; LARA GONZÁLEZ, LUIS ÁNGEL; Moreno, J J (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

A magneto-dielectric material composed of a polyester resin-based microstrip (P115A), copper sheets and magnetite powders was designed in concentrations of 10, 20 and 30% Wt and with filters of 200, 325 and 500. The particles ...
Design and manufacture of the cooling system of JUPITER reactor

Hector Jaime, Dulce-Moreno; Gélvez Arocha, O A; Dugar-Zhabo, V D; Rodríguez-Villamiza, C D; V-Niño, E D (Journal of Physics: Conference SeriesBogota , Colombia, 2019-02-25)

The experimental investigations carried out in the Plasma laboratory of the Universidad Industrial de Santander, on superficial modification of metallic materials by hybrid discharges of high-voltage and electric arc at ...
Design and simulation of a mechanical system for the machining of parts and printing in 3D (x, y, z)

Miranda Molina, Luis Antonio; Quinayas Ortiz, Asdrúbal Maximino; Peña Rodriguez, Gabriel (Revista UIS Ingenierías, 2020-07-30)

The design and simulation of a multifunctional system for the machining of mechanical parts and printing in 3D (x, y, z) using CAD software Solid works, was used to determine the static behavior of the system with the ...
Determination of correlation of compressive strength with maturity of concrete mixed with accelerator

Peña Rodriguez, Gabriel; Medrano Lindarte, Carmen Teresa; García-Páez, Ismael H. (Journal of Physics: Conference SeriesLondres, Reino Unido, 2019-11-29)

The compressive strength of concrete mixtures with accelerator additives designed for structural elements with strength of 5000 psi was correlated with the maturity index of concrete at an early age. The design of the ...
Efecto de la concentración de magnetita en la estructura, propiedades eléctricas y magnéticas de un material compuesto a base de resina de poliéster

Peña Rodriguez, Gabriel; Rivera-Suárez, Paola A.; González-Gómez, César H.; Parra-Vargas, Carlos A.; Garzón-Posada, Andrés O.; Landínez-Téllez, David A.; Roa-Rojas, Jairo (TecnoLógicasBogota , Colombia, 2018-01-15)

Se reporta el efecto de la concentración de polvos de magnetita (Fe3O4) sobre las propiedades eléctricas y magnéticas de un material compuesto a base de resina de poliéster termoestable. Las muestras se elaboraron mediante ...
Effect of concentration of starch in the properties morphological and structural of porous ceramic based on expansive clays

Peña Rodriguez, Gabriel; Dulce Moreno, Hector Jaime; Ferrer Pacheco, Martha Yasmid; Suarez, M; Bermudez, D (Journal of Physics: Conference SeriesLondres, Reino Unido, 2020-03-06)

In this article is used the sacrificial material method to generate different porosities between 44.42% and 69.14% in ceramics based on expansive clays from San Jose de Cúcuta metropolitan area, Colombia, to analyze the ...
Effect of surface roughness on nitriding processes by dielectric barrier discharges of carbon steel

Hector Jaime, Dulce-Moreno; Peña Rodriguez, Gabriel; Quiñonez-Delgado, Y P; Arriaga-Hurtado, L G (Journal of Physics: Conference SeriesBogota , Colombia, 2017-12-29)

Changes in the behaviour of steels to carbon, for three different finishes, surfaces were determined to be nitride by atmospheric pressure dielectric barrier discharge. The surfaces were characterized both morphologically ...
Effective thermal properties and proximate analysis of coke-coal fines mixtures

Soto Rivero, M F; Quintero Garzón, A C; Peña Rodríguez, G; Miranda Molina, L A; Sepulveda Solano, G (Reino Unido, 2021-06-04)

We report the effective thermal properties at room temperature and proximate analysis of three mixtures of coke and carbon fines formed by uniaxial pressing at 30 MPa. Using differential scanning calorimetry and ...
Effective thermal properties of a magnetite-polyester composite conformed in the presence of a constant magnetic field

LARA GONZÁLEZ, LUIS ÁNGEL; Peña Rodriguez, Gabriel; Pineda Triana, Yaneth (AIMS Materials ScienceWashintong D.C , Estados Unidos, 2019-07-02)

In this study, we report the thermophysical properties (at room temperature) and the morphology of a composite with a polyester resin matrix and magnetite filler powders (Fe3O4), conformed in three configurations: randomly ...
Elaboración y caracterización de recubimientps de polvos de ZnSCu y resinas de poliester sobre sustratos cerámicos de arcilla roja, para el diseño de fachadas y revestimientos arquitectónicos fosforescentes

Ferrer, Martha; Rodríguez Vega, Luisa Fernanda; Peña Rodriguez, Gabriel (Bistua Revista De La Facultad De Ciencias BasicasBogota , Colombia, 2018)

En este estudio se elaboran y caracterizan recubrimientos de polvos ZnSCu y resinas de poliéster termoestables sobre sustratos cerámicos de arcilla roja, para el diseño de fachadas y revestimientos arquitectónicos ...
Elaborar y caracterizar pastas cementantes fosforescentes a base de geopolímeros dopados con aluminatos de estroncio para aplicaciones ambientales

Peña Rodriguez, Gabriel (Universidad Francisco de Paula SantanderCúcuta, Norte de Santander, 2021-08-25)

Dentro de las técnicas de tratamiento de aguas y aires, existe la fotocatálisis o fotoelectrocatalisis, donde el principio físico es la interacción de la radiación con la materia, utilizándose la radiación UV proveniente ...
Electrochemical characterization of the steel wire used as reinforcement in the conductors transmission networks electricity nitride by ion implantation

Hector Jaime, Dulce-Moreno; Aperador Chaparro, William Arnulfo; Castro Maldonado, J J (Journal of Physics: Conference SeriesBogota , Colombia, 2016-02-12)

The power company feature infrastructure, which are generally shaped so the transmission and distribution lines, here is why it is necessary to characterize the process of electrochemical corrosion of these components. In ...
Electrochemical synthesis of titanium dioxide nanostructures and its application in the in dye photocatalytic removal

RIVERA BERMUDEZ, INGRID PAOLA; Alarcón Rodríguez1, V; Peña Rodríguez, G (Reino Unido, 2021-06-04)

By electrochemical anodization to titanium sheets, titanium dioxide nanostructures were sintered for 10 V and 20 V and times of 3 hours and 5 hours. For the electrolytic solution, 0.3 g of ammonium fluoride, 97 mL of ...
ForistomApp a Web application for scientific and technological information management of Forsitom foundation

Hector Jaime, Dulce-Moreno; Saavedra-Duarte, L A; Angarita-Jerardino, A; Ruiz, P A; Vera-Rivera, F. H.; V-Niño, E D (Journal of Physics: Conference SeriesBogota , Colombia, 2017-12-29)

Information and Communication Technologies (ICT) are essential in the transfer of knowledge, and the Web tools, as part of ICT, are important for institutions seeking greater visibility of the products developed by their ...
Manufacture of oxy-acetylene thermally sprayed coating on refractory subtrates from unconventional feedstock material

Cadavid, Edwin; Vargas, Fabio; LÓPEZ GÓMEZ, MARIA ESPERANZA; Mesa, Carlos; Vargas, Fabio; LATORRE, GUILLERMO; Peña Rodriguez, Gabriel (DYNABogota , Colombia, 2018-04-01)

A chromite mineral and two industrial residues produced in the petrochemical and thermoelectric industries, were selected, characterized, processed and deposited on refractory bricks. By means of X-ray fluorescence and ...

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Aplicación de FeO, ZnO y CuO como pigmentos en compuestos cerámicos
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ROA BOHÓRQUEZ, KAROL LIZETH | 2019-04-12

Entre los problemas más relevantes de la industria alfarera de Boyacá, Colombia, se encuentra la ausencia de una gama de tonalidades uniformes de sus productos finales. El color, por tratarse de una propiedad física fácilmente observable, se convierte en un criterio distintivo para clientes potenciales que buscan un producto diferenciador y a la vanguardia dentro de un medio en constante cambio. Por tal razón, el presente trabajo propuso un compuesto cerámico elaborado a partir de arcillas montmorillonitas y óxidos metálicos tales como FeO, CuO y ZnO. Las arcillas se caracterizaron por Fluorescencia de Rayos X (FRX) y de acuerdo a la composición química de cada arcilla, se determinaron las concentraciones de los óxidos metálicos como agentes colorantes, los cuales variaron de 1 a 8 % (en peso). Los prototipos cerámicos se conformaron por el método de prensado uniaxial a una presión de compactación constante de 15 MPa, posteriormente se sinterizaron a 950 °C durante 2 h. Mediante histogramas RGB se realizaron los análisis de color de los especímenes, los resultados mostraron cambios significativos en la pigmentación del compuesto cerámico reportando tono rojo, café y blanco. Lo anterior, hace viable la utilización de estos óxidos como pigmentos termoestables en la elaboración de productos cerámicos tales como: tejas, tabletas y baldosas, entre otros diseños cerámicos que hoy en día solo se pueden encontrar en tiendas de cerámica avanzada.

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Application of maturity method to estimate compressive strength of mass concrete
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Gamba Gomez, Osmar Albert | 2019-11-29

The correlation between the maturity index and the compressive strength of concrete is validated for mixtures with strengths of 2000, 2500, 3000 and 3500 PSI, which are the most used in the civil engineering field. Temperature probes DS18B20 connected by the 1-Wire protocol to the Raspberry Pi 3 card were used to census the data and calculate the maturity index. The concrete mixtures presented A/C ratios of 0.820, 0.748, 0.680 and 0.623, which are consistent with those used in the construction industry. Compressive strength tests were performed every 24 hours during a 28-day test scenario in order to understand the behavior of concrete throughout the curing process. From the values of mechanical resistance to compression obtained in the control ages of 7 and 14 days it is inferred that the concrete has a normal hardening, likewise when comparing the experimental results of the resistance to compression, with those found using the method of maturity, it was possible to identify that at early ages (less than 10 days) they present uncertainties greater than 10% while at ages greater than 10 days of curing this error does not exceed 5%. In general, it was evidenced that the assembly carried out with the Raspberry pi 3 card and DS18B20 probes reliably allowed the monitoring, recording and storage of temperature and time data during the entire curing process.

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Arduino data-logger and artificial neural network to data analysis
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Hector Jaime, Dulce-Moreno | 2019-11-29

This work takes thermodynamic modelling through computer science for incubation process at domestic birds, that has presented energy consumption significantly high than energy used in processes. Thus, a data analysis was applied upon variables of temperature and relative humidity for heating zones, trying to know how much energy supplied by source was used, as well as, voltage and current variables are measured in the same moment that temperature and relative humidity are acquired. Then, data analysis was done using artificial neural networks models with samples obtained from sensors, where real process is highly time- variant, fixing environment conditions at the moment required. Therefore, with this system has been obtained an air flow of 3.4375 10−2 m3/J using a anemometer respect to electrical energy supplied by fans, giving 9.4818 W of average power using ceramics resistances, and testing an adaptive controller where its variables are fitted using equations obtained from data analysis. In contrast, colombian farmers have decreased economic conditions to maintain them productions due to free trade agreements implemented lastly, indeed this system was developed using open- source software and hardware to avoid costs in acquisition by licensing politicians or periodic subscription to a specific product developed by companies.

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Characterization of commercial luminescent powders
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Peña Rodriguez, Gabriel | 2019-11-29

Luminescent powders have attracted the attention of scientists, boosting properties as specific as mechanoluminescence, thermoluminescence, and photoluminescence among other characteristics. The uses of these properties have grown exponentially from recreational uses in luminescent paints, toys, plasticines, and other industry-specific uses, such as crack sensors, flaw detectors, and radiation meters in medicine. These uses have grown proportionately with their more economical and efficient manufacturing methods and processes, generating more economical fluorescent pigments. This paper characterizes and compares a low-cost luminescent pigment with those reported by different authors, its chemical composition was characterized by X-ray energy dispersion spectrometry, X-ray fluorescence, and Raman spectroscopy. Its morphology was analyzed by scanning electron microscopy, and its particle size with a laser meter its structural condition with X-ray diffraction, the powder obtained was presented as a strontium alumínate doped with divalent europium and trivalent dysprosium (Al2O4: Eu2+, Dy3+) one of the most efficient powders around persistence and luminance intensity at present. The structure of the strontium aluminate was determined by the main peaks of the diffractogram showing a monoclinic system. The elemental composition helped to determine the doping of the strontium aluminate corroborating them with the obtained with Raman spectroscopy and the scanning electron microscopy images.

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Coating of tricalcium phosphates by flame spray
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Ferrer, Martha | 2019-11-29

The metal alloys used for prostheses with high mechanical requirements are bioinerts, it means they have low integration with bone tissue, therefore, bioactive coatings are used in order to improve this integration. Hydroxyapatite is one of the most studied materials for this application with good results, however, sometimes there are problems due to wear or tear of the coating leading prostheses loss. Tricalcium phosphate, Ca3(PO4)2, in its different phases shows osteoconductivity and higher solubility than hydroxyapatite, however, few studies have been carried out to determine its behavior as a coating for this type of applications. In this work, a study of the behavior of tricalcium phosphate as a coating on Ti6Al4V substrates obtained by flame spraying was carried out. As raw material were used tricalcium phosphate powders obtained by precipitation from calcium nitrate and ammonium phosphate dihydrogen solution, and subsequent calcination at 1,100°C. The Ca/P molar ratio obtained is 1.48 and the only present crystalline phase is beta -tricalcium phosphate. The coatings obtained have alpha tricalcium phosphate as only crystalline phase, they have compact morphology with low porosity and good wettability with the substrate, which is an index of good adhesion and good mechanical behavior. The transformation from beta- to alpha- tricalcium phosphate is product of the high temperatures used in the process, which are higher than 1,125°C where this transformation occurs.

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Design and characterization of a magneto-dielectric composite in high frequency with aligned magnetite powders
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Peña Rodriguez, Gabriel | 2019-11-29

A magneto-dielectric material composed of a polyester resin-based microstrip (P115A), copper sheets and magnetite powders was designed in concentrations of 10, 20 and 30% Wt and with filters of 200, 325 and 500. The particles were aligned vertically and horizontally during the curing process using 300 mT magnetic fields. From a complete factorial design of 33, 27 microstrip-type circuits of 4 mm width, 70 mm length and 0.93 mm thickness were manufactured, characterized by scanning electron microscopy and vector network analysis. The cross-matrix analysis determined an optimal circuit response from the magneto-dielectric material with a concentration of 20% magnetite and an average particle size of 21.48 μm in horizontal alignment to the applied magnetic field and to the transmission line, obtaining a relative dielectric constant of Er 3.88 with a low dielectric loss of 0.054, within an operating range of 150 KHz to 4 GHz.

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Design and manufacture of the cooling system of JUPITER reactor
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Hector Jaime, Dulce-Moreno | 2019-02-25

The experimental investigations carried out in the Plasma laboratory of the Universidad Industrial de Santander, on superficial modification of metallic materials by hybrid discharges of high-voltage and electric arc at low pressures are carried out in the joint universal plasma and ion technologies experimental reactor. The cooling system of the reactor is by water, which means that it is directly connected to the water supply line of the building, which creates a dependence on the system. Additionally, the water supply line is often filled with particles that accumulate in the cooling system, disfavoring the transfer of energy between the water, the vacuum system and the cathode, which can lead to overheating of the reactor and melt the elements that make up the electric power system. In accordance with the above, the present research work consists of designing, building and implementing an efficient cooling system totally independent from the water supply line of the building, which allows to recirculate and minimize water consumption in order to take care of the natural resource.

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Design and simulation of a mechanical system for the machining of parts and printing in 3D (x, y, z)
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Miranda Molina, Luis Antonio | 2020-07-30

The design and simulation of a multifunctional system for the machining of mechanical parts and printing in 3D (x, y, z) using CAD software Solid works, was used to determine the static behavior of the system with the analysis of tension, deformation, displacement, safety factor, buckling, fatigue and frequency. For the above, it was determined that the lateral base supports a tension of 3.5x108 Pa, causing a displacement of 25 mm and an equivalent unit strain (ESTRN) of 0.0012. And the base guiding a cumulative damage of 300% of deterioration that reduces its useful life to a range between 1x106 and 1x1065 utility cycles and a safety factor (F S) between 104.632 to 7869.86. On the other hand, the transverse base has a maximum cumulative damage percentage of 4.10535 and a life cycle range ranging from 24358.5 to 1x106 with a minimum SF of 5974

LEER
Determination of correlation of compressive strength with maturity of concrete mixed with accelerator
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Peña Rodriguez, Gabriel | 2019-11-29

The compressive strength of concrete mixtures with accelerator additives designed for structural elements with strength of 5000 psi was correlated with the maturity index of concrete at an early age. The design of the mixture was made by adding the quantity of additives according to the specifications of the supplier. The maturity index was calculated using the thermal profile of the concrete dependent of the setting time, which was obtained through an automated adiabatic system. The number of thermal sensors required for temperature measurement dependent of setting time (1, 3, 7, 14 and 28 days) was determined by a factorial experimental design of two factors. The correlation coefficient was 0.96, so the logarithmic model adequately explains the variability of the compressive strength. The equation obtained was validated by means of the values of resistance to compression measured by the standard method for each age of the concrete; all values are within the calibration range of the resistances estimated by the maturity method.

LEER
Efecto de la concentración de magnetita en la estructura, propiedades eléctricas y magnéticas de un material compuesto a base de resina de poliéster
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Peña Rodriguez, Gabriel | 2018-01-15

Se reporta el efecto de la concentración de polvos de magnetita (Fe3O4) sobre las propiedades eléctricas y magnéticas de un material compuesto a base de resina de poliéster termoestable. Las muestras se elaboraron mediante el método de colado manual en concentraciones de: 60-40, 70-30, 80-20, 90-10 y 100-0 (% en peso), donde la fase mayoritaria es la resina y la minoritaria los óxidos de Fe3O4. La estructura cristalina se estudió usando la técnica de difracción de rayos X y la caracterización superficial tuvo lugar a través de la técnica de microscopía electrónica de barrido. Se midió la respuesta eléctrica por medio de curvas de polarización eléctrica en función del campo eléctrico y de resistividad eléctrica volumétrica a través de un electrómetro. La respuesta magnética se determinó mediante curvas de magnetización en función de la intensidad de campo magnético aplicado y en función de la temperatura. El análisis estructural indica que el porcentaje de cristalinidad aumenta a medida que se adiciona la concentración de Fe3O4 a las muestras. La caracterización eléctrica del material evidencia que la resistividad volumétrica disminuye con el incremento de magnetita, mostrando una transición aislante-conductor, con valores de la constante dieléctrica cada vez mayores. La caracterización magnética evidencia un aumento lineal de la magnetización de saturación y del momento magnético en función de la cantidad de magnetita adicionada a la matriz polimérica, mientras que la coercitividad evidencia comportamientos de materiales magnéticos blandos tanto en T˃TV como en T<TV, donde TV representa la temperatura de Verwey

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Effect of concentration of starch in the properties morphological and structural of porous ceramic based on expansive clays
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Peña Rodriguez, Gabriel | 2020-03-06

In this article is used the sacrificial material method to generate different porosities between 44.42% and 69.14% in ceramics based on expansive clays from San Jose de Cúcuta metropolitan area, Colombia, to analyze the effect of concentration of starch (porogenic agent) in the morphological and structural properties using calcium carbonate as a stabilizer. The porous ceramics was characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. Finally, the images were analyzed with the software Image J, Image Tool and Origin. The results showed that the weight concentration of starch has a relationship with the average pore size, the number of pores and the porous area of the samples where the percentage of porous area and the average pore size of the mixtures increases as starch is added due to the decay of the sacrificial material. The number of pores of the mixtures decreased by increasing the weight concentration of the starch due to the agglomeration of the starch.

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Effect of surface roughness on nitriding processes by dielectric barrier discharges of carbon steel
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Hector Jaime, Dulce-Moreno | 2017-12-29

Changes in the behaviour of steels to carbon, for three different finishes, surfaces were determined to be nitride by atmospheric pressure dielectric barrier discharge. The surfaces were characterized both morphologically and structurally before and after the treatment. The techniques used were: measurement of roughness and electrochemical testing (Tafel). Results show changes differential depending on the type of finish, but in any case, an improvement of corrosion resistance.

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Effective thermal properties and proximate analysis of coke-coal fines mixtures
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Soto Rivero, M F | 2021-06-04

We report the effective thermal properties at room temperature and proximate analysis of three mixtures of coke and carbon fines formed by uniaxial pressing at 30 MPa. Using differential scanning calorimetry and thermogravimetry, the thermal behavior of the carbon samples was determined. The KD2 Pro® system was used to measure the effective thermal properties, while the proximate analysis was carried out applying the ASTM D 3172-89 standard. It was found for coke fines that in the range between 40.00 °C and 293.94 °C there is a loss in weight of 3.2%, which corresponds to the degradation of low molecular weight volatiles, another degradation was also observed between 90.07 °C and 336.21 °C, and the maximum devolatilization temperature was 579 °C, finally from 700 °C the melting process begins, which corresponds to the formation of coke. It was also observed that the thermal conductivity increases with increasing coke concentration in the sample, and that the mixture with the highest thermal diffusivity was the one formed with 80% coke fines and 20% carbon fines. According to the thermal properties of the samples can be to be used efficiently as fuel.

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Effective thermal properties of a magnetite-polyester composite conformed in the presence of a constant magnetic field
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LARA GONZÁLEZ, LUIS ÁNGEL | 2019-07-02

In this study, we report the thermophysical properties (at room temperature) and the morphology of a composite with a polyester resin matrix and magnetite filler powders (Fe3O4), conformed in three configurations: randomly dispersed particles, particles oriented parallel to a constant 300 mT magnetic field, and particles oriented perpendicular to a constant 300 mT magnetic field. Samples were formed by hand lay-up with weight percentages of 10, 20 and 30%, where the highest concentration corresponds to the resin. The thermophysical properties were determined using the KD2 Pro® system, which uses the physical principle of linear transient heat flow, for which the dual sensor SH-1 was used. The morphology and microanalysis were studied using a scanning electron microscope (SEM, FEI Quanta 650 FEG). It was observed from the morphology that the magnetite particles are oriented in the direction of the magnetic field lines during the process of resin curing. It was also perceived that the values of the thermophysical properties found experimentally are within the limits (upper and lower) of Hashin and Shtrikman and that those values increase when the magnetite concentration increases in the sample. No significant difference was observed in the thermal properties because of the magnetic field applied.

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Elaboración y caracterización de recubimientps de polvos de ZnSCu y resinas de poliester sobre sustratos cerámicos de arcilla roja, para el diseño de fachadas y revestimientos arquitectónicos fosforescentes
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Ferrer, Martha | 2018

En este estudio se elaboran y caracterizan recubrimientos de polvos ZnSCu y resinas de poliéster termoestables sobre sustratos cerámicos de arcilla roja, para el diseño de fachadas y revestimientos arquitectónicos fosforescentes. Los recubrimientos se conforman a partir de mezclas de polvos, resina y catalizador en diferentes porcentajes. Se estudia sus propiedades en función de la concentración del polvo agregado a la mezcla. La información comparativa de las diferentes concentraciones de polvo fosforescente y resina de poliéster permiten determinar no solo su caracterización, sino también la toma de decisiones en el diseño y aplicación en futuras propuestas arquitectónicas, relacionadas con fachadas o revestimientos que absorban luz ultravioleta o solar durante el día y su fosforescencia durante la noche.

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Elaborar y caracterizar pastas cementantes fosforescentes a base de geopolímeros dopados con aluminatos de estroncio para aplicaciones ambientales
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Peña Rodriguez, Gabriel | 2021-08-25

Dentro de las técnicas de tratamiento de aguas y aires, existe la fotocatálisis o fotoelectrocatalisis, donde el principio físico es la interacción de la radiación con la materia, utilizándose la radiación UV proveniente del sol. Por lo anterior, se pretende elaborar y caracterizar morfológica, estructural, térmica, mecánica y ópticamente muestras de una pasta cementante fosforescente a base de geopolímeros dopadas con aluminatos de estroncio, para concentraciones en peso del 10, 20 y 30%. La pasta cementante se elaborará agregando caolín y solución salina de silicato de sodio con hidróxido de sodio, para lo cual se agitará mediante agitador de cabezal a 800 rpm. Una vez obtenida la pasta cementante se agregarán las concentraciones definidas de los polvos comerciales de aluminato de estroncio, y se elaborarán las probetas para su respectiva caracterización. Lo anterior se realizará por triplicado con el objeto de disminuir las incertidumbres en las medidas experimentales. La caracterización estructural se realizará mediante difracción de rayos X (DRX), la morfología y microanálisis usando microscopia electrónica de barrido (EDS-MEB), las térmicas a temperatura ambiente mediante flujo transitorio plano de calor, y las ópticas mediante la irradiación con lámpara UV de 15W acoplada a una cámara web de alta definición, la cual registrara el tiempo de emisión de la fosforescencia de la muestra para un tiempo definido de irradiación, en función de la concentración del aluminato de estroncio. Lo anterior permitirá definir las mejores condiciones, para que la pasta pueda ser utilizada en revestimientos o tanques para el tratamiento de aguas o gases mediante fotocatálisis o fotoelctrocátalisis, ya que dicho proceso puede ser dado en doble vía, primero con la interacción directa de la radiación sobre el semiconductor (aluminato de estroncio), y posteriormente en ausencia de la radiación debido a la fosforescencia emitida; otra de las aplicaciones de la pasta fosforescente es de auto-iluminación donde absorberá radiación durante el día y la emitirá en la oscuridad, sirviendo como demarcación o señalización, en construcciones civiles o vías

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Electrochemical characterization of the steel wire used as reinforcement in the conductors transmission networks electricity nitride by ion implantation
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Hector Jaime, Dulce-Moreno | 2016-02-12

The power company feature infrastructure, which are generally shaped so the transmission and distribution lines, here is why it is necessary to characterize the process of electrochemical corrosion of these components. In this case the steel wire coated with zinc or aluminium, as it is undergoes the rigor of corrosive environments. Given the geographical diversity and different climatic environments, atmospheric corrosion carried affecting service life of structures. For example in very humid environments such as coasts and high altitudes, wetting time (TOW), parameter that meets the conditions of temperature and relative humidity, it affects large proportion, accelerating the corrosion of ferrous materials. Given the importance of establishing mechanisms that lessen the impact on degradation in transmission and distribution lines of both the reliability and the availability of the same. This paper presents the implementation in nitride steels as an alternative or complement to zinc coating.

LEER
Electrochemical synthesis of titanium dioxide nanostructures and its application in the in dye photocatalytic removal
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RIVERA BERMUDEZ, INGRID PAOLA | 2021-06-04

By electrochemical anodization to titanium sheets, titanium dioxide nanostructures were sintered for 10 V and 20 V and times of 3 hours and 5 hours. For the electrolytic solution, 0.3 g of ammonium fluoride, 97 mL of ethylene glycol and 3 mL of distilled water were used. The sheets (51 mm × 21 mm × 0.4 mm) were treated using abrasive paper and cleaned with a 1:1 solution of ethanol water by means of ultrasound and dried using hot air. A stirring frequency of 300 rpm was used during anodizing. For the sintering of the titanium dioxide anatase phase, heat treatment was applied at 550 °C for 3 hours by means of an electric muffle, with heating speed of 10 °C/min. The crystallinity index, and the quantification of the sintered phases was carried out by means of X-ray diffraction, while the nanoporosities and their distribution were carried out using imageJ software to the images taken by means of scanning electron microscopy. For the photocatalytic treatment of the methylene blue dye in water, the titanium dioxide nanostructures that reported the highest anatase phase were used, where ultraviolet C radiation from a led lamp was applied for 4 direct hours. The efficiency in the removal of the dye was studied by UV-Vis spectrophotometry, finding the highest degradation of the dye for the wavelength of 644 nm.

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ForistomApp a Web application for scientific and technological information management of Forsitom foundation
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Hector Jaime, Dulce-Moreno | 2017-12-29

Information and Communication Technologies (ICT) are essential in the transfer of knowledge, and the Web tools, as part of ICT, are important for institutions seeking greater visibility of the products developed by their researchers. For this reason, we implemented an application that allows the information management of the FORISTOM Foundation (Foundation of Researchers in Science and Technology of Materials). The application shows a detailed description, not only of all its members also of all the scientific production that they carry out, such as technological developments, research projects, articles, presentations, among others. This application can be implemented by other entities committed to the scientific dissemination and transfer of technology and knowledge.

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$Portada Manufacture of oxy-acetylene thermally sprayed coating on refractory subtrates from unconventional feedstock material$

Manufacture of oxy-acetylene thermally sprayed coating on refractory subtrates from unconventional feedstock material
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Cadavid, Edwin | 2018-04-01

A chromite mineral and two industrial residues produced in the petrochemical and thermoelectric industries, were selected, characterized, processed and deposited on refractory bricks. By means of X-ray fluorescence and X-ray diffraction the chemical composition and crystallographic phases of raw materials were analyzed, morphology and particle size was determinate using Scanning Electron Microscopy. The materials were deposit by oxyacetylene thermal spray on silica-alumina refractory bricks and high alumina low cement concrete, commercial references ER-40 and CBC-50 from ERECOS S.A.S.. The parameters used for the coating deposition were optimized based on preliminary test and simulations using the Jets&powders software. The chromite mineral coating displayed greater structure homogeneity than the other two coatings; the last ones presented partially melted particles and high porosity. However, based on the chemical composition, the response to adhesion test and the crystallographic phases present in the coatings, all of them are potential candidates to be used as protective barriers against corrosive effects on refractories.

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