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Dise?o y construcción de un go-kart híbrido pila de combustible PEM / batería recargable
SUáREZ-ALCáNTARA, Karina;RODRíGUEZ-CASTELLANOS, Andrés;SOLORZA-FERIA, Omar;
Revista internacional de contaminación ambiental , 2008,
Abstract: an hybrid polymer electrolyte membrane fuel cell, pemfc-rechargeable battery go-kart has been designed and manufactured using autocad software for the design and a cnc mechanical machine for the manufacture of components of the fuel cell. the membrane-electrode assemblies, meas, were integrated with a gore-select membrane and carbon cloth with pt (20 wt % /c) 0.5 mg/cm2 anode and cathode electrode catalysts loading. high density graphite collector plates with 5mm thickness were used as collector plates. the estimated weigh of the go-kart with a driver is about 120 kg. the demand of the motor of the go-kart is 20 v and 5 a (100w), supplied by an hybrid system integrated by three 30watts pemfc. the commercially available pb/acid rechargeable battery supplies energy for peripheral equipment.
Solar-Hydrogen-Fuel Cell Prototype as a Source of Renewable Energy Generation
Andrés Rodríguez-Castellanos,Ernesto López-Torres,Omar Solorza-Feria
Revista de la Sociedad Química de México , 2007,
Abstract: Se presenta un peque o prototipo para la utilización de una fuente de energía renovable. Un modulo fotovoltaico fue utilizado para la electrólisis del agua donde el hidrógeno producido fue suministrado a una celda de combustible regenerativa para la producción de electricidad. El módulo fotovoltaico suministra corriente directa, CD, a un electrolizador para producir 56 cm3/min de hidrógeno el cual es alimentado a una celda de combustible para producir electricidad. El prototipo fue dise ado y construido para mostrar el escenario futuro de una energía renovable. Para la electrólisis del agua se utilizaron polvos electrocatalizadores de RuCoOx y Pt nanométrico como ánodo y cátodo, respectivamente, integrados a una membrana polimérica. El catalizador anódico fue preparado por pirólisis a la temperatura de 550 °C. Se prepararon ensambles membranaelectrocatalizador, MEAs, los cuales fueron estudiados galvanostáticamente y bajo iluminación en módulo fotovoltaico. Se obtuvo un alto desempe o electroquímico del electrolizador con 0.25 A cm-2 a 1.87 V para cada ensamble, a la temperatura de 30 °C y presión atmosférica de 585 mmHg. Un prototipo con arreglos de celda de combustible fue dise ado y construido utilizando 10 MEAs conteniendo 0.4 mg/cm2 de Pt al 20 % peso como ánodo y cátodo y así generar energía eléctrica para hacer funcionar una TV portátil de 3.5 watts.
DISE O Y CONSTRUCCIóN DE UN GO-KART HíBRIDO PILA DE COMBUSTIBLE PEM / BATERíA RECARGABLE
Karina SUáREZ-ALCáNTARA,Andrés RODRíGUEZ-CASTELLANOS,Omar SOLORZA-FERIA
Revista internacional de contaminación ambiental , 2008,
Abstract: En este trabajo se presenta el dise o y la construcción de un go-kart híbrido pila de combustible con membrana de conducción protónica tipo PEM (Proton Exchange Membrane, por sus siglas en inglés) y pila recargable. El dise o de los colectores de corriente de la pila se realizó utilizando el programa AutoCAD y la construcción mediante una fresadora con control numérico, CNC. Los ensambles membrana-electrocatalizador de la pila están formados por membranas Gore-Select y por electrodos de Pt soportado en tela de carbón al 20 %peso/C con carga de 0.5 mg /cm2, en ánodo y cátodo. Los platos colectores de corriente fueron manufacturados en grafito de alta densidad con espesor de 5 mm. La caracterización de la pila de combustible se realizó mediante ensayos de polarización potenciostática. El peso total del go-kart y una persona a bordo es de 120 kg. La potencia del go-kart es generada por un motor de corriente directa de 20 V y 5 A (100 Watts). Para tal efecto, se construyeron tres pilas de combustible de 30 W cada una, con un respaldo de baterías recargables comerciales de Pb/ácido para energizar equipos periféricos.
Electrochemical Behavior of Ni-Mo Electrocatalyst for Water Electrolysis
Fernández-Valverde, Suilma Marisela;Ordo?ez-Regil, Eduardo;Caba?as-Moreno, Gerardo;Solorza-Feria, Omar;
Journal of the Mexican Chemical Society , 2010,
Abstract: nickel-molybdenum based electrolcatalysts were synthesized in organic media for the hydrogen evolution reaction (her) and oxygen evolution reaction (oer) in alkaline media. the strutture, morphology, and chemical composition of the catalysts were evaluated by xrd, sem and aas. results revealed nanocristalline powder materials with ni0.006mo, ni0.1mo, and nimo compositions. the best performance for her, was obtained on ni0.1mo electrode, whereas nimo was for the oer. results suggest that the material with 1: 1 stoichiometric ratio could be considered as a promising electrocatalyst for oer. this nanotrystalline powder is formed by ni2mo3o8 and a crystalline structure attributed to the possible formation of a nimo cluster, becomes nimoo4 after thermal treatment at 1073k in air. the nimo 1:1 cluster catalyst presented electrochemical stability during the oer.
Biochemical evaluation of protein fractions from physic nut (Jatropha curcas L.)
Peralta-Flores, L.,Gallegos-Tintoré, S.,Solorza-Feria, J.,Dávila-Ortíz, G.
Grasas y Aceites , 2012, DOI: 10.3989/gya.072511
Abstract: J. curcas seed proteins were fractioned according to the Osborne method and some biochemical properties were determined for these fractions. Glutelins (378 g kg–1 protein) and globulins (201 g kg–1 protein) were the main components. Albumins and prolamins were the minor components. Protein digestibility was highest in glutelins and globulins with values of 81 and 80% respectively. Electrophoresis analysis showed that globulins and glutelins exhibited similar polypeptide profiles. Electrophoresis patterns suggested that there could be a structural relationship among 2S, 7S and 11S storage proteins from plant sources. According to the FAO WHO reference, the protein fractions had acceptable levels of most of the essential amino acids, but its globulins and glutelins were low in lysine and tryptophan. Las proteínas de semillas de J. curcas L. se fraccionaron empleando el método de Osborne y posteriormente se determinaron algunas de sus propiedades bioquímicas y nutricionales. Las fracciones mayoritarias resultaron ser glutelinas (378 g kg–1 de proteína) y globulinas (201 g kg–1 de proteína) mientras que las albúminas y prolaminas fueron las fracciones minoritarias. La digestibilidad de la proteína resultó ser más alta en las glutelinas y globulinas, con valores de 81 y 80% respectivamente. El análisis por electroforesis mostró que las globulinas y glutelinas presentaron perfiles similares, los resultados sugieren que podría existir una relación con proteínas de almacenamiento 2S, 7S y 11S de origen vegetal. Asimismo, de acuerdo con la FAO/WHO, las fracciones proteínicas tuvieron niveles aceptables para la mayoría de los aminoácidos esenciales, sin embargo, las globulinas y glutelinas fueron deficientes en Lys y Trp.
Electrochemical Behavior of Ni-Mo Electrocatalyst for Water Electrolysis
Suilma Marisela Fernández-Valverde,Eduardo Ordo?ez-Regil,Gerardo Caba?as-Moreno,Omar Solorza-Feria
Revista de la Sociedad Química de México , 2010,
Abstract: Electrocatalizadores base níquel-molibdeno fueron sintetizados en medio orgánico para la reacción de evolución de hidrógeno (HER) y reacción de evolución de oxígeno (OER) en medio alcalino. La estructura, morfología y composición química de los catalizadores fueron evaluados por XRD, SEM y AAS. Los resultados obtenidos mostraron polvos de materiales nanocristalinos con composición química de Ni0.006Mo, Ni0.1Mo y NiMo. El mejor desempe o para la HER fue en electrodos de Ni0.1Mo, y para la OER en NiMo, sugiriendo que el NiMo puede ser considerado como el mas prometedor para OER. El NiMo está compuesto de Ni2Mo3O8 y un cluster de NiMo que se transforma en NiMoO4 después de un tratamiento térmico a 1073K en aire. El catalizador NiMo 1:1 mostró estabilidad electroquímica durante la OER.
Efecto del tiempo de reacción en la acetilación del almidón de plátano
Guerra-DellaValle, D.;Bello-Pérez, L. A.;González-Soto, R. A.;Solorza-Feria, J.;Arámbula-Villa, G.;
Revista mexicana de ingeniería química , 2008,
Abstract: plantain starch was acetylated at different times; the degree of substitution, reaction rate constant, morphology, x-ray diffraction pattern and thermal characteristics were evaluated. the degree of substitution (ds) rose with the reaction time and consequently the reaction efficiency increased. the reaction rate constant was higher in plantain (0.67 h-1) starch than in maize starch (0.23 h-1). fourier transform infrared spectroscopy confirmed the introduction of acetyl groups in the starch molecule and the signal characteristic of this group (1226 cm-1) was higher at longer reaction times. the starch granule surface, observed by scanning electron microscopy, showed more changes when the reaction time increased and those were minimal in plantain starch. this pattern agreed with the higher crystallinity peaks measured by x-ray diffraction in plantain starch and an amorphous pattern obtained in acetylated maize starch. peak temperature (74.8 °c for native plantain starch and 71 °c for its acetylated counterpart) and enthalpy of gelatinization (12.89 j/g for native plantain starch and 7.44 j/g for its acetylated counterpart) decreased in the acetylated starches and the effect was higher at longer reaction times. it is possible to determine a reaction time in order to obtain an acetylated plantain starch with specific ds and physicochemical and functional properties.
Mechanically milled RuxFey Electrocatalyst for Oxygen Reduction in acid media
P. Sotelo-Mazón, R.G. González-Huerta, J. G. Caba?as-Moreno, O. Solorza-Feria
International Journal of Electrochemical Science , 2007,
Abstract: Electrocatalytic oxygen reduction reaction (ORR) on RuxFey fine particles prepared by mechanical milling was investigated in a sulfuric acid electrolyte. The activity of the catalysts with Vulcan carbon powder dispersed into a Nafion film coated on a glassy carbon (ink-type electrode) was studied by using the rotating disk electrode technique, RDE. Polarization measurements showed that the ORR occurs through a first order reaction with respect to oxygen with a mechanism involving four electrons transfer to water formation. A Tafel slope of ca. 0.120 V dec-1, and an exchange current density of 5.08 x 10-5 mA cm-2 was deduced from the mass transfer corrected polarization curves. The kinetic parameters were compared with commercial electrocatalysts and are in agreement with previous results for other types of Ru-based electrocatalysts, prepared in organic solvents.
Properties of Edible Films Based on Oxidized Starch and Zein
Elizabeth Argüello-García,Javier Solorza-Feria,J. Rodolfo Rendón-Villalobos,Francisco Rodríguez-González,Alfredo Jiménez-Pérez,Emmanuel Flores-Huicochea
International Journal of Polymer Science , 2014, DOI: 10.1155/2014/292404
Abstract: The objective of this work was to investigate the effect of zein and film formulation on mechanical and structural properties of native (FNS), and oxidized with 2.5% (FOSA) and 3.5% (FOSB) banana starch. The oxidized starch showed differences from native starch due to the oxidation process, showing a decrease in lipids, proteins, and amylose. The increase of the sodium hypochlorite increased the content of carbonyl and carboxyl groups in the ranges 0.015–0.028% and 0.022–0.031%, respectively. The film obtained from FOSB displayed the highest tensile strength (5.05?MPa) and satisfactory elongation value (27.1%). The zein addition caused a decrease in these mechanical properties, as well as a significant decrease in water vapour permeability (WVP). However, films from FOSA and FOSB showed higher permeability than that of the native starch. The addition of glycerol and the level of oxidation increased the films moisture. Micrographs showed that, during the oxidation process, impurities were largely eliminated from the starch granule, noting more homogeneous structures both in granules and films. 1. Introduction There is currently a revival of worldwide interest in the use of biopolymers for applications in which synthetic polymers have traditionally been the materials of choice. Materials of interest include different synthetic or biosynthetic polymers [1, 2], as well as plant based polymers such as polysaccharides, starch, and cellulose, which represent the most characteristic family of these natural polymers [3–6]. In the polymer field, interest in starch, a well-known hydrocolloid biopolymer, has been recently renewed due to its abundance, low-cost, biodegradability, and the possibility of processing, using conventional polymer processing equipment [7–9]. Starch is produced from various sources in the form of granules and is mainly isolated from cereal grains such as maize, wheat, rice, and sorghum although tubers such as potato, cassava, sweet potato, and sago are also used, and it can be found in leaves legume seeds and fruits as well. It is composed of amylose, a linear polymer (poly-α-1,4-D-glucopyranoside), which is distributed mostly in the starch granule amorphous domains (lamella), with small amounts in the semicrystalline granule ring and amylopectin (poly-α-1,4-D-glucopyranoside and α-1,6-D-glucopyranoside), a branched polymer that gives place to the crystalline lamella [10, 11]. The relative amounts and molar masses of amylose and amylopectin vary with the starch source, yielding materials of different mechanical properties and
EVALUACIóN DE LA REGENERACION DE Acacia decurrens, Acacia melanoxylon Y Ulex europaeus EN áREAS EN PROCESO DE RESTAURACIóN ECOLóGICA
SOLORZA BEJARANO,JAIRO HERNáN;
Luna Azul , 2012,
Abstract: regeneration of acacia decurrens, acacia melanoxylon and ulex europaeus in an area subject to the process of ecological restoration was evaluated. in areas with acacia decurrens and acacia melanoxylon arboreal individuals expression of seed banks with periodic accumulation of fallen leaves that stop or divert the succession process is present. in open areas ulex europaeus regeneration occurs quickly occupying areas without vegetation. the plantation of native shrubby or arboreal species, along with periodic monitoring of the regeneration and fallen leaves formation of alien species, facilitate the activation of secondary succesion mechanisms, increasing the richness, diversity and evenness of species in the ecosystem.
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