786 resultados para Catalisadores heterogêneos


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In this work, ceramic powders belonging to the system Nd2-xSrxNiO4 (x = 0, 0.4, 0.8, 1.2 and 1.6) were synthesized for their use as catalysts to syngas production partial. It was used a synthesis route, relatively new, which makes use of gelatin as organic precursor. The powders were analyzed at several temperatures in order to obtain the perovskite phase and characterized by several techniques such as thermal analysis, X-rays diffraction, Rietveld refinement method, specific surface area, scanning electron microscopy, energy dispersive spectroscopy of X-rays and temperature programmed reduction. The results obtained using these techniques confirmed the feasibility of the synthesis method employed to obtain nanosized particles. The powders were tested in differential catalytic conditions for dry reforming of methane (DRM) and partial oxidation of methane (POM), then, some systems were chosen for catalytic integrals test for (POM) indicating that the system Nd2-xSrxNiO4 for x = 0, 0.4 and 1.2 calcined at 900 °C exhibit catalytic activity on the investigated experimental conditions in this work without showing signs of deactivation

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La presente tesis doctoral se centra en el estudio y clasificación de los recursos empleados en el diseño con tipografía en el medio cinematográfico. Se consideran estas unidades desde el punto de vista estético/formal, sin olvidar su aporte narrativo, por su condición de elemento significativo de lectura autónoma y/o a la vez integrado en la estructura diegética de la obra cinematográfica. Esa integración, basada en la coherencia de estilo gráfico global, se estima que vertebra la concreción de la identidad visual de la obra para ayudar a convertir el producto en marca comercial. Por otro lado, se ilustra la influencia recíproca que se establece entre los diseños de secuencias de título de crédito principales, sobreimpresiones con tipografía, teasers y pósters con lo desarrollado en géneros mixtos tan heterogéneos como el spot publicitario, el vídeo musical y, sobre todo, el vídeo arte y el cine experimental. La estética de todos estos formatos va estrechamente ligada a la incorporación de nuevas técnicas de producción para estos diseños. De ahí la necesidad de clasificar esas técnicas y su aplicación a la composición con tipografía. El proyecto se articula en distintos capítulos que abordan todos y cada uno de los aspectos relacionados con la tipografía en cine: carteles cinematográficos, secuencias de créditos principales y el uso expresivo de sobreimpresiones con tipografía en el contexto argumental. Se ha estimado conveniente solo citar tangencialmente el diseño tipográfico más estrechamente ligado con la ejecución física de la dirección artística del film, ya sea en letreros de decorados o piezas de atrezzo recreadas. El cuerpo de estudio incluye principalmente, no por casualidad, una mayor proporción de filmes norteamericanos. El sector cinematográfico en los EE.UU. además de su mayor volumen de producción, ha sido el primero en ver en el diseño una herramienta eficaz e imprescindible para vender sus productos. Su concepto de industria va parejo a la necesidad de generar la idea de marca en sus productos. Con todo esto, se ha ofrecido un recorrido por las distintas formas de presentar estas informaciones, mediante una clasificación original que ayuda a un mejor acercamiento a las obras y, asimismo, plantear un amplio muestrario que ayude a diseñadores y realizadores a abordar sus trabajos aprovechando al máximo las posibilidades expresivas de estos recursos. Aunque ya existen numerosas publicaciones sobre carteles cinematográficos, ordenados por épocas, géneros e incluso autores, estas siempre se centran en el contenido fotográfico o ilustración, relegando la componente tipográfica a un limbo incomprensible. La pormenorizada estructuración de recursos compositivos con tipografía desarrollada es totalmente inédita. En cuanto a la atención al específico empleo de tipografía en la propia película, tipos en movimiento, en los últimos diez años se ha comprobado un creciente interés por las secuencias de títulos de crédito gracias a diferentes publicaciones de desigual calibre. Entre las principales fuentes cabe destacar: BASS, J., KIRKHAM, P., Saul Bass, a life in film & design, Laurence King Publishing, Londres 2011 BELLANTONI, J., WOOLMAN, M., Tipos en movimiento, Index Books, Barcelona 2000 BETANCOURT, M., The history of motion graphics, from avant-garde to industry in the United States, Wildside Press, Savannah 2013 CODRINGTON, A., Kyle Cooper, Laurence King Publishing, Londres 2003 HERVAS IVARS, C., El diseño gráfico en televisión: técnica, lenguaje y arte, Cátedra, Madrid 2002 HORAK, J., Saul Bass, Anatomy of film design, University Press of Kentucky, Kentucky 2014 SOLANA, G., BONEU, A., Uncredited, Diseño gráfico y títulos de crédito, Index Book S.L., Barcelona 2007

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O presente relatório descreve a prática profissional desenvolvida no Centro de Apoio ao Desenvolvimento Infantil (CADIn), no âmbito do Ramo de Aprofundamento de Competências Profissionais (RACP), enquadrado no 2º Ano do 2º Ciclo de Reabilitação Psicomotora, correspondente ao ano letivo 2014/2015. O trabalho desenvolvido no CADIn foi realizado, principalmente, junto de crianças e jovens com Dificuldades de Aprendizagem Específicas (DAE). As DAE, de origem neurobiológica e intrínsecas ao indivíduo, caracterizam-se por um conjunto de traços heterogéneos que se manifestam na aquisição e uso das competências auditivas, da fala, da leitura, da escrita, do raciocínio e/ou matemáticas. Podem coexistir com outras perturbações, como é o caso da Perturbação de Hiperatividade e Défice de Atenção (PHDA). A heterogeneidade dos perfis de aprendizagem de crianças com DAE torna o processo de intervenção um desafio permanente. Neste sentido, a intervenção psicomotora surge como uma resposta que permite o desenvolvimento holístico do indivíduo, viabilizando a apropriação dos processos simbólicos. O relatório está organizado em Enquadramento da Prática Profissional, que inclui o Enquadramento Teórico e o Enquadramento Institucional, e Realização da Prática Profissional, onde são abordados dois estudos de caso, de uma forma mais detalhada.

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Dissertação de Mestrado, Engenharia Informática, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, Programa de Pós-Graduação em Química, 2011.

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Tese de Doutoramento, Ciências do Mar da Terra e do Ambiente, Ramo: Ciências e Tecnologias do Ambiente, Especialidade em Biotecnologia, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016

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Efforts in research and development of new technologies to reduce emission levels of pollutant gases in the atmosphere has intensified in the last decades. In this context, it can be highlighted the modern systems of electronic engine management, new automotive catalysts and the use of renewable fuels which contributes to reduce the environmental impact. The purpose of this study was a comparative analysis of gas emissions from a automotive vehicle, operating with different fuels: natural gas, AEHC or gasoline. To execute the experimental tests, a flex vehicle was installed on a chassis dynamometer equipped with a gas analyzer and other complementary accessories according to the standard guidelines of emission and security procedures. Tests were performed according to NBR 6601 and NBR 7024, which define the urban and road driving cycle, respectively. Besides the analysis of exhaust gases in the discharge tube, before and after the catalyst, using the suction probe of the gas analyzer to simulate the vehicle in urban and road traffic, were performed tests of fuel characterization. Final results were conclusive in indicating leaded gasoline as the fuel which most contributed with pollutant emissions in atmosphere and the usual gasoline being the fuel which less contributed with pollutant emissions in atmosphere

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Biodiesel is an alternative fuel, renewable, biodegradable and nontoxic. The transesterification of vegetable oils or animal fat with alcohol is most common form of production of this fuel. The procedure for production of biodiesel occurs most commonly through the transesterification reaction in which catalysts are used to accelerate and increase their income and may be basic, acid or enzyme. The use of homogeneous catalysis requires specific conditions and purification steps of the reaction products (alkyl ester and glycerol) and removal of the catalyst at the end of the reaction. As an alternative to improve the yield of the transesterification reaction, minimize the cost of production is that many studies are being conducted with the application of heterogeneous catalysis. The use of nano-structured materials as catalysts in the production of biodiesel is a biofuel alternative for a similar to mineral diesel. Although slower, can esterify transesterified triglycerides and free fatty acids and suffer little influence of water, which may be present in the raw material. This study aimed at the synthesis, characterization and application of nano-structured materials as catalysts in the transesterification reaction of soybean oil to produce biodiesel by ethylic route. The type material containing SBA-15 mesoporous lanthanum embedded within rightly Si / La = 50 was used catalyst. Solid samples were characterized by X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, nitrogen adsorption and desorption. For the transesterification process, we used a molar ratio of 20:1 alcohol and oil with 0.250 g of catalyst at 60°C and times of 6 hours of reaction. It was determined the content of ethyl esters by H-NMR analysis and gas chromatography. It was found that the variable of conversion obtained was 80%, showing a good catalytic activity LaSBA-15 in the transesterification of vegetable oils via ethylic route

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The fast pyrolysis of lignocellulosic biomass is a thermochemical conversion process for production energy which have been very atratactive due to energetic use of its products: gas (CO, CO2, H2, CH4, etc.), liquid (bio-oil) and charcoal. The bio-oil is the main product of fast pyrolysis, and its final composition and characteristics is intrinsically related to quality of biomass (ash disposal, moisture, content of cellulose, hemicellulose and lignin) and efficiency removal of oxygen compounds that cause undesirable features such as increased viscosity, instability, corrosiveness and low calorific value. The oxygenates are originated in the conventional process of biomass pyrolysis, where the use of solid catalysts allows minimization of these products by improving the bio-oil quality. The present study aims to evaluate the products of catalytic pyrolysis of elephant grass (Pennisetum purpureum Schum) using solid catalysts as tungsten oxides, supported or not in mesoporous materials like MCM-41, derived silica from rice husk ash, aimed to reduce oxygenates produced in pyrolysis. The biomasss treatment by washing with heated water (CEL) or washing with acid solution (CELix) and application of tungsten catalysts on vapors from the pyrolysis process was designed to improve the pyrolysis products quality. Conventional and catalytic pyrolysis of biomass was performed in a micro-pyrolyzer, Py-5200, coupled to GC/MS. The synthesized catalysts were characterized by X ray diffraction, infrared spectroscopy, X ray fluorescence, temperature programmed reduction and thermogravimetric analysis. Kinetic studies applying the Flynn and Wall model were performed in order to evaluate the apparent activation energy of holoceluloce thermal decomposition on samples elephant grass (CE, CEL and CELix). The results show the effectiveness of the treatment process, reducing the ash content, and were also observed decrease in the apparent activation energy of these samples. The catalytic pyrolysis process converted most of the oxygenate componds in aromatics such as benzene, toluene, ethylbenzene, etc

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Aiming to reduce and reuse waste oil from oily sludge generated in large volumes by the oil industry, types of nanostructured materials Al-MCM-41 and Al-SBA-15, with ratios of Si / Al = 50, were synthesized , and calcined solids used as catalysts in the degradation of oily sludge thermocatalytic oil from oilfield Canto do Amaro, in the state of Rio Grande do Norte. Samples of nanostructured materials were characterized by thermogravimetric analysis (TG / DTG), X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectroscopy in the infrared Fourier transform (FT-IR) and adsorption nitrogen (BET). The characterization showed that the synthesized materials resulted in a catalyst nanostructure, and ordered pore diameter and surface area according to existing literature. The oily sludge sample was characterized by determining the API gravity and sulfur content and SARA analysis (saturates, aromatics, resins and asphaltenes). The results showed a material equivalent to the average oil with API gravity of 26.1, a low sulfur content and considerable amount of resins and asphaltenes, presented above in the literature. The thermal and catalytic degradation of the oily sludge oil was performed from room temperature to 870 ° C in the ratios of heating of 5, 10 and 20 ° C min-1. The curves generated by TG / DTG showed a more accelerated degradation of oily sludge when it introduced the nanostructured materials. These results were confirmed by activation energy calculated by the method of Flynn-Wall, in the presence of catalysts reduced energy, in particular in the range of cracking, showing the process efficiency, mainly for extraction of lightweight materials of composition of oily sludge, such as diesel and gasoline

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Tese (doutorado)—Universidade de Brasília, Departamento de Economia, Brasília, 2016.

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The oily sludge is a complex mix of hydrocarbons, organic impurities, inorganic and water. One of the major problems currently found in petroleum industry is management (packaging, storage, transport and fate) of waste. The nanomaterials (catalysts) mesoporous and microporous are considered promising for refining and adsorbents process for environment protection. The aim of this work was to study the oily sludge from primary processing (raw and treated) and vacuum residue, with application of thermal analyses technique (pyrolysis), thermal and catalytic pyrolysis with nanomaterials, aiming at production petroleum derived. The sludge and vacuum residue were analyzed using a soxhlet extraction system, elemental analysis, thin layer chromatography, thermogravimetry and pyrolysis coupled in gas chromatography/mass spectrometry (Py GC MS). The catalysts AlMCM-41, AlSBA-15.1 e AlSBA-15.2 were synthesized with molar ratio silicon aluminum of 50 (Si/Al = 50), using tetraethylorthosilicante as source of silicon and pseudobuhemita (AlOOH) as source of aluminum. The analyzes of the catalysts indicate that materials showed hexagonal structure and surface area (783,6 m2/g for AlMCM-41, 600 m2/g for AlSBA-15.1, 377 m2/g for AlSBA-15.2). The extracted oily sludge showed a range 65 to 95% for organic components (oil), 5 to 35% for inorganic components (salts and oxides) and compositions different of derivatives. The AlSBA-15 catalysts showed better performance in analyzes for production petroleum derived, 20% increase in production of kerosene and light gas oil. The energy potential of sludge was high and it can be used as fuel in other cargo processed in refinery

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El proyecto se desarrolla desde un planteamiento metodológico que se basa en las aulas inversas o "FLIPPED CLASSROOM", Aprender haciendo, aprendizaje significativo y aprendizaje colaborativo. Para ello se realiza el análisis de estilos de aprendizaje, se realizan sesiones formativas sobre el uso de la Pizarra Digital Interactiva como recurso tecnológico. La propuesta de enseñanza-aprendizaje, se desarrolla a través de la virtualización en el Campus Virtual de la asignatura. Las clases se organizan para el trabajo colaborativo, aplicando dinámicas de grupo que permiten facilitar los procesos de conocimiento entre los alumnos, para pasar a la formación de grupos heterogéneos, a través de la técnica del sociograma. Se Proponen tareas que se realizan en el aula, en trabajo colaborativo. Los alumnos trabajan la información con anterioridad, en casa, revisando la documentación del campus. El aprendizaje colaborativo a través del Campus supone desarrollar competencias en TIC y permite la construcción de aprendizajes significativos.

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O presente relatório de mestrado em Educação Pré-Escolar e Ensino do 1.º Ciclo do Ensino Básico integra duas partes distintas, designadamente a dimensão reflexiva e a dimensão investigativa. Na dimensão reflexiva apresentam-se reflexões críticas e fundamentadas a respeito do percurso e do trabalho desenvolvido nos diferentes contextos de Prática Pedagógica. Nesta parte procurou-se relatar aprendizagens realizadas pela mestranda a partir da sua intervenção nos diversos contextos. Para além disso, são também parte integrante desta dimensão o ser educador e professor, e um assunto significativo ocorrente da Prática Pedagógica, nomeadamente o interesse da observação. Na dimensão investigativa apresenta-se um estudo de caso que se centra em questões da temática da diferenciação pedagógica/pedagogia diferenciada com crianças integradas em grupos heterogéneos a nível de aprendizagem e desenvolvimento, incidindo sobre a implementação de estratégias diferenciadas nos primeiros anos de vida. Sendo a temática do estudo a diferenciação pedagógica/pedagogia diferenciada formulou-se a seguinte questão de partida: “Como utilizar estratégias de diferenciação pedagógica para a construção de salas inclusivas?”. A implementação das estratégias diferenciadoras revelaram a existência de um crescente grau de autonomia e de responsabilidade patente no desenvolvimento do trabalho, de organização do espaço, dos materiais e do tempo; uma maior motivação dos alunos. A realização deste estudo permitiu responder de forma mais consciente e organizada às necessidades de cada aluno respeitando as suas dificuldades e ritmos de aprendizagens diferenciados.