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New approach to hybrid multiplexer using composite right-left handed lines

TEJINDER KAUR KATARIA ALONSO CORONA CHAVEZ Tatsuo Itoh (2011)

In this letter, a new approach to hybrid multiplexer is proposed which is based on the frequency dispersive characteristic of the Composite Right Left Handed (CRLH) lines, which in conjunction with dual band filters permit one single module to handle two frequencies. This allows size reduction since only half as many modules are required for multiband systems. Simulated and measurement responses are presented showing good agreement.

Article

Composite right left handed (CRLH) lines Defected ground surface Filters Multiplexer CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

Dual-Band Multi-Pole Directional Filter for Microwave Multiplexing Applications

Humberto Lobato Morales ALONSO CORONA CHAVEZ Tatsuo Itoh JOSE LUIS OLVERA CERVANTES (2011)

A novel microstrip directional filter for multiplexing applications is presented. This device uses composite right-left-handed transmission lines and resonators to achieve dual-band frequency response. In addition, by cascading two or more stages using dual frequency immitance inverters, multi-pole configurations can be obtained. Simulation and experimental results are presented with good agreement.

Article

Composite right-left-handed (CRLH) lines Directional filters Microwave filters Slow-Wave (SW) resonators CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

Diseño para minorías: problemas de lateralidad en la manipulación de objetos diestros por usuarios zurdos

Irma Alejandra Zafra Ballinas (2002)

179 páginas. Maestría en Diseño.

Investigación que se enfoca al estudio de la conducta corporal humana con relación a la manipulación de objetos. De manera más específica este comportamiento será analizado por medio de los movimientos de manos, haciendo hincapié en la observación del uso de los objetos diferenciando a zurdos y diestros. Se considera también la posibilidad de análisis que se puede tener por el comportamiento interrelacionado con la vista y las manos.

Master thesis

Left- and right-handedness. Destreza manual Zurdos y diestros Diseño de producto GN233 HUMANIDADES Y CIENCIAS DE LA CONDUCTA PSICOLOGÍA PSICOLOGÍA SOCIAL COMPORTAMIENTO DEL CONSUMIDOR

Synthesis and magnetoelectric characterization of cobalt ferrite—barium titanate composites using a new pulsed magnetic field method

MARIA EUGENIA BOTELLO ZUBIATE DARIO BUENO BAQUES LUIS EDMUNDO FUENTES COBAS JOSE ANDRES MATUTES AQUINO (2006)

BaTiO3-CoFe2O4 composites synthesized by the ceramic method showed a magnetoelectric effect. The CoFe2O4 powders were synthesized by coprecipitation and mixed with Aldrich reactive quality BaTiO3 powders with particle size <2 μm. The coupling of the magnetostrictive and the piezoelectric phases via elastic deformations of the properly polarized composites produced a magnetoelectric effect. The starting powders and the composites were characterized by thermal analysis, x-ray diffraction with Reitveld refinements, scanning electron microscopy and particle size distribution using light scattering. The magnetoelectric coefficient, α = dE/dH, was measured using the dynamic method, and a new pulsed magnetic field method developed in our laboratory.

Article

Cobalt Derrite magnetoelectric composite magnetic pulsed fields CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA OTRAS ESPECIALIDADES FÍSICAS OTRAS

Fabricación de álabes de un rotor de eje vertical para un generador

JORGE ESTEBAN GUERRA BRAVO ELIAS RIGOBERTO LEDESMA OROZCO (2015)

En este proyecto se muestra el proceso de fabricación de uno deloscuatro álabes de unmetro de alturaque se adaptarán a un rotor de eje vertical para un generador eólico, se utilizó un composite fibrosoel cual se conforma por un refuerzo y una matriz para el refuerzose optó por utilizar fibra de vidrio por su precio y sus propiedades adecuadas para el proceso, como matriz se utilizó resina epoxica. El proceso de fabricación utilizado VARTM (Vacuum assisted resin transfer molding)o proceso de moldeo por transferencia de resina asistido de vacío, se utilizó por ser un método efectivo y preciso ya que el álabe requiere de un acabado uniformetanto como superficies lisasy este proceso es ideal para la fabricación del álabe.Los resultados fueronpróximos a los quese esperaron, la superficie del álabe uniforme y con rugosidad mínimay la forma estructural propuesta, el proceso fue eficientey puede mejorarse para los álabes que se fabricarán posteriormente

In this project is shown the manufacturing process of one of the four blades of a meter in height to adapt to a vertical axis rotor for a wind generator, was used a fiber composite which is formed by a reinforcement and a matrix was used as strengthening and chose to used fiberglass for its price and suitable for the process, the epoxy resin matrix was used by its properties. The manufacturing process used VARTM (Vacuum assisted resin transfer molding) was used by be an effective and accurate method since the blade requires an even finish and this process is ideal for blade manufacture. The results were close to those expected, the blade surface with uniform roughness was minimal, and the way structural was the proposal, the process is efficient and can be improved for the blades which is subsequently manufactured

Article

INGENIERÍA Y TECNOLOGÍA Composite Resina Vacío

Facile synthesis and characterization of MnxZn1-xFe2O4/activated carbon composites for biomedical applications

Jorge Carlos Ríos Hurtado JOSE RENE RANGEL MENDEZ ELIA MARTHA MUZQUIZ RAMOS (2016)

"The synthesis of MnxZn1-xFe2O4 ferrites (x = 0.4, 0.5 and 0.6) by means of the co-precipitation method is reported. Furthermore, a composite of Mn0.4Zn0.6Fe2O4/activated carbon was prepared with the mechanosynthesis method. The magnetic, structural, morphological and chemical properties were analyzed by means of VSM, XRD, SEM, FTIR and Boehm's titration. The heating capacity was evaluated under a magnetic field using solid-state induction heating equipment, in addition a hemolysis test was performed using human red blood cells. With regard to the synthesis of manganese-zinc ferrite, the results indicated that Mn0.4Zn0.6Fe2O4 ferrite showed higher saturation magnetization (64.48 emu/g) than the other ferrite obtained, with superparamagnetic behavior. The Mn0.4Zn0.6Fe2O4/activated carbon composite was able to heat in concentrations of 10 mg/ml under a magnetic field (10.2 kAm-1 and frequency 200 kHz), increasing the temperature up to 42.5 °C. The hemolysis test indicated that the presence of activated carbon reduces the hemolytic behavior of the ferrite. Thanks to its heating capacity and non-hemolytic activity, theMn0.4Zn0.6Fe2O4/activated carbon composite is a potential candidate for use in biomedical applications."

Article

Mn-Zn ferrite Superparamagnetic Activated carbon Composite Hemolysis INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS CIENCIAS TECNOLÓGICAS

Malachite green dye behaviors in the presence of biosorbents from maize (Zea mays L.), their Fe-Cu nanoparticles composites and Fe-Cu nanoparticles

EYMAR JIMENA LARA VASQUEZ Marcos José Solache Ríos Edith Eriela Gutiérrez Segura (2016)

The sorption behaviors of biosorbent based on maize (Zea mays, ZM) cane (bagasse and stalk), their composites (ZM/Fe-Cu nanoparticles) and Fe-Cu nanoparticles for malachite green from aqueous solutions were investigated in this work. Adsorbents were characterized using BET, infrared spectroscopy, X-ray diffraction, SEM-EDS, and Fe-Cu nanoparticles were characterized by TEM. The study of the sorption kinetics indicates that the adsorption on malachite green by stalk and their composite follows second-order kinetics and nanoparticles and bagasse and their composite follow the pseudo-second order model. The malachite green adsorption by ZM/Fe-Cu composites were faster than natural materials and only showed two phases in the intraparticle diffusion model, probably due to the minor internal diffusion resistance. The adsorption isotherms experimental data were analyzed by the Langmuir, Freundlich and Langmuir–Freundlich models and the equilibrium data was well described by the Langmuir–Freundlich isotherm model. The adsorption was more favorable at basic pH. The OH-groups were proportional to dye adsorption capacities. Results showed that composites (ZM/Fe-Cu nanoparticles) and Fe-Cu nanoparticles possessed good adsorption abilities to malachite green.

Project 3688/2014/CIB UAEM

Article

Fe-Cu nanoparticles Composite Maize Malachite green Adsorption BIOLOGÍA Y QUÍMICA

LA SOLUCIÓN DE CONFLICTOS EN EL DERECHO INTERNACIONAL, BASE DEL SISTEMA DE JUSTICIA PENAL Y DE LOS DERECHOS HUMANOS EN MÉXICO

GUADALUPE VAUTRAVERS TOSCA (2015)

A nivel internacional, desde el año de 1899 se procuraba conciliar y mediar, hasta resolver los conflictos por medio del arbitraje, para evitar las guerras y desde hace 34 años el gobierno de México ratificó los más importantes instrumentos internacionales en materia de Derechos Humanos, por lo que las reformas al Sistema Jurídico Mexicano han llegado muy tarde y confiamos en que sean debidamente respetadas y aplicadas.

Article

CIENCIAS SOCIALES International right Human rights Conflict Resolution Accusatorial system Mexico Tabasco

Degradación fotocatalítica de colorantes usando nanopartículas de titania soportadas en materiales metal-orgánicos basados en hierro

DIANA CAROLINA GARCIA MARTINEZ (2018)

117 páginas. Maestría en Ciencias e Ingeniería de Materiales.

Consejo Nacional de Ciencia y Tecnología (México).

Los colorantes cuando son descargados a los ríos y mares a través de las aguas residuales que produce la industria textil principalmente, representan un enorme daño al ecosistema, dado que por sí solos no son capaces de degradarse. Es necesario el desarrollo de nuevos métodos que permitan eliminar los colorantes de manera efectiva como la degradación fotocatalítica, utilizando fotocatalizadores y luz solar. Los materiales denominados redes metal-orgánicas (MOFs por sus siglas en inglés) los cuales son una nueva clase de materiales cristalinos formados por la unión de clústeres metálicos a través de ligandos orgánicos, son una buena alternativa como fotocatalizadores ya que presentan diferentes propiedades como: elevada versatilidad estructural y de composición, altas superficies específicas y volúmenes de poro, diferentes tamaños de poro, centros metálicos expuestos y flexibilidad de la estructura. En el presente trabajo se sintetizaron cinco diferentes MOFs: (MIL-53 (Fe), MIL-100 (Fe), MIL-101 (Fe), 235 (Fe) y Fe-BTC) por el método hidrotermal/solvotermal y mecanoquímico. Se sintetizaron nanopartículas de óxido de titanio (TiO2) a partir del método de sonoquímica que fueron usadas para ser incorporadas en las MOFs con el objetivo de incrementar sus propiedades fotocatalíticas en la reacción de degradación de colorantes. Los materiales sintetizados se caracterizaron utilizando diferentes técnicas analíticas tales como: difracción de Rayos -X, espectroscopia UV-Vis, Raman e IRTF y microscopia electrónica de barrido. Los materiales compositos fueron utilizados en la degradación del colorante Negro Reactivo 5, Orange II e Índigo Carmín, mostrando excelentes resultados al lograr degradar la mayor cantidad de los colorantes. A pesar de que todos los materiales presentaron excelente actividad fotocatálitica, las MOF MIL-100 (Fe) presentaron el mayor porcentaje de degradación y mayor velocidad de degradación en menor tiempo.

Master thesis

Water--Purification--Photocatalysis. Composite materials. Nanostructured materials. Agua -- Purificación -- Fotocatálisis. Materiales nanoestructurados. TD468 INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS INGENIERÍA Y TECNOLOGÍA DEL MEDIO AMBIENTE TECNOLOGÍA DE AGUAS RESIDUALES

Chitosan–Starch–Keratin composites: Improving thermo-mechanical and degradation properties through chemical modification

CYNTHIA GRACIELA FLORES HERNANDEZ ARTURO COLIN CRUZ CARLOS VELASCO SANTOS Víctor Manuel Castaño Meneses IMELDA OLIVAS ARMENDARIZ Ana Laura Martínez Hernández (2017)

The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable features

Chitosan–starch polymers are reinforced with different keratin materials obtained from chicken feather. Keratin materials are treated with sodium hydroxide; the modified surfaces are rougher in comparison with untreated surfaces, observed by Scanning Electron Microscopy. The results obtained by Differential Scanning Calorimetry show an increase in the endothermic peak related to water evaporation of the films from 92 °C (matrix) up to 102–114 °C (reinforced composites). Glass transition temperature increases from 126 °C in the polymer matrix up to 170–200 °C for the composites. Additionally, the storage modulus in the composites is enhanced up to 1614 % for the composites with modified ground quill, 2522 % for composites with modified long fiber and 3206 % for the composites with modified short fiber. The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable features

Universidad Autónoma del Estado de México Tecnológico Nacional de México, Instituto Tecnológico de Querétaro Universidad Nacional Autónoma de México Tecnológico Nacional de México, Instituto Tecnológico de Celaya Universidad Autónoma de Cd. Juárez

Article

Chemical modification Keratin Chicken feather Sodium hydroxide Biopolymer composite BIOLOGÍA Y QUÍMICA