695 resultados para Celulas solares


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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In this work were studied associations of ZnO with the natural products caffeic and feluric acids. Two preparation methods were used, that is, the sol-gel and a reflux procedure. In the sol-gel method, ZnO is produced by the basics hydrolysis of precursors in the presence of the organic filters (caffeic and feluric acids), which results in 30 nm (or less) ZnO particles with the organic filters (in dissociated form) bonded to the surface of ZnO. In the reflux method, a dispersion of ZnO in a water/ethanol mixture was kept under reflux (50oC/4h) in the presence of the organic acids. The ZnO particles used in the reflux method have a higher diameter than sol-gel ZnO particles, but the prepared associated product ZnO/Organic acids were similar. Despite of the difference in relation to crystallinity between the products, the preparation methods resulted in analogous associations with respect to the interaction of the organic filters with the ZnO surface. The caffeic/ZnO associations presented low photostability, which lead to the degradation of the organic filter. The other associations (feluric acid/ZnO) presented satisfactory results. The FT-IR spectroscopy confirmed the formation of the association, and the nature of the bond formed compared with the Zn-O bond in Zn2+/Felutic acid complexes. The isolated organic and inorganic filters, along with the associations were analyzed by diffuse reflectance spectroscopy and Uv-vis spectroscopy. The absorption edges and the critical wavelengths were analyzed and the effects of Zn-O bonds in feluric acid/ZnO associations described as a function of the relative position of the π/π* system of the organic filter. Finally the performance of the hybrid filters were investigated in terms of the absorption of UVA and UVB radiations, with the UVA/UVB ratio, an efficiency parameter largely used in the description of solar filters, sunscreen and suncare products

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Through the data acquisition system of the instrument Brazilian Solar Spectroscope (BSS) at INPE, solar observations in the decimetric radio wave band (1000-2500 MHz) are regularly made. This data is showed as dynamic spectra using the software BSSView created for this purpose. The process of data acquisition can be influenced by various sources, dificulting the resulting dynamic spectrum analysis. The objective of this work is to create a computational routine that eliminates dynamic components of the spectrum attributed to interfering signals and integrate it into BSSView. It was done a preliminary study on the programming language Interactive Data Language (IDL), in which the BSSView was developed, and the Fourier transform, that is required for the application of the filter

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One of society concerns are preserving the environment and the growing energy demand. These two issues are in conflict since most of the energy used today in some way harms the environment. Then is essential to develop and implement ways to clean and renewable energy. In this way, solar energy stands out as a source of clean energy, renewable, abundant and acessible. Solar energy can be harnessed by photovoltaic cells or by solar collectors. The aim of this article is analysethe yield of the solar heather assembled with hydraulic conductive and plastic bottles using three different materials for hydraulic conductors, in order to compare these efficiences and analyze material which has the best cost-benefit in this type of application. The materials analyzed in this study were copper, aluminum and PVC. For this analysis were assembled three alike solar heaters using each one of these materials, and were done several series of measurements of the temperature water output to each heat with flow between 10 and 30 liters per hour. With these data we can analyze the yield and the performance of copper, aluminum and PVC in this application. So we can conclude that aluminum has a higher efficiency, followed by PVC, and the copper had the lowest efficiency. This behavior kept for all values of flow rates examined

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Este trabalho apresenta o uso de energia solar, para o aquecimento de água, através da análise de aquecedores solares industrial e os construídos com garrafas PET com canos condutores de água de cobre, alumínio e PVC, instalados no Centro de Energias Renováveis - CER, do Campus de Engenharia Guaratinguetá. A análise foi realizada com a ajuda de sensores Termopar, software - Contemp View Simple, para obtenção de dados, software Teamviewer para acesso remoto. Sendo feitas as medições concluiu-se qual é o aquecedor mais eficiente a ser utilizado, sempre tendo como objetivo o aproveitamento da energia renovável usando a radiação solar

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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In order to diversify the global and national energy matrix and reduce harmful impacts on the environment caused by the emission of polluting gases into the atmosphere, the use of clean and renewable energy sources is presented as a good alternative. This work discusses the use of photovoltaic solar energy, a source that presents such characteristics. The photovoltaic system under study is the type distributed connected to the grid, in the residential segment. It is informed of its use in the global and national levels. They are also present their characteristics, electrical and electronic circuits that make up the equipment required for its operation and the design of a system to be installed in a residence

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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In order to diversify the global and national energy matrix and reduce harmful impacts on the environment caused by the emission of polluting gases into the atmosphere, the use of clean and renewable energy sources is presented as a good alternative. This work discusses the use of photovoltaic solar energy, a source that presents such characteristics. The photovoltaic system under study is the type distributed connected to the grid, in the residential segment. It is informed of its use in the global and national levels. They are also present their characteristics, electrical and electronic circuits that make up the equipment required for its operation and the design of a system to be installed in a residence

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Fil: Gambetta Chuk, Aída Nadí.

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A partir de los nuevos paradigmas que conocemos como Novelas Históricas Posmodernas, el escritor mexicano retoma esa extensa línea temática que se origina en el acontecimiento histórico que convulsionó, a principios del siglo XX, la extensa geografía mexicana. El objetivo de este trabajo es abarcar el estudio de las tres novelas de Solares que se ocupan de textualizar episodios de la Revolución: Madero, el otro, de 1989, La noche de Ángeles, de 1991, Columbus, 1996. La elección de las figuras manifiesta la intención de devolverles su verdadera voz desde esa mirada que sólo permite la ficción, en tanto los hechos contados surgieron “más de lo simbólicamente verdadero que de lo históricamente exacto". La atención estará en destacar la presencia de voces que, desde una particular focalización, se ocuparán de insertar en el discurso modalizaciones diversas. Estas voces habrán de problematizar, con mayor o menor intensidad según los diversos registros, impugnando, cuestionando o rescatando ciertos actos oscuros del pasado, llevados a cabo por quienes protagonizaron la gesta revolucionaria. El tono apelativo característico explicita, por otra parte, el lugar desde el cual la historia debe ser leída.

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El objetivo de este artículo fue encontrar un sinergismo entre los máximos de actividad solar y las lluvias caídas en Azul, Pcia. de Buenos Aires (36°45' S; 59°57' O y altitud: 137 m s. n. m.), empleándose una serie de precipitaciones anuales desde 1913 hasta 2012. Los resultados mostraron que los últimos cuatro máximos de actividad solar se relacionan con los años de mayores precipitaciones. Las precipitaciones anuales para dichos años, presentaron un promedio de 1317 mm (2,4 desvíos estándar sobre la media) que resultó significativamente diferente a la media de los últimos cien años (855,7 mm ±191,1 mm). Se encontró una relación positiva entre los años de máxima actividad solar y la aparición de eventos extremos en las precipitaciones, que generan excesos hídricos e inundaciones en el sector rural y urbano de Azul.

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A partir de la tesis de que la literatura es el resultado de una construcción social de la realidad y de que lejos de buscar representar una realidad externa a su textualidad construye la propia, quisiera insistir en un asunto que si bien parte de esta visión, tiene otros fines que no se conforman con la descripción de las estructuras formales ni con el análisis de la participación del lector o la reconstrucción del contexto, sea de la obra en cuanto objeto cultural, sea del contexto de la historia contada en el mundo narrado. Para tal efecto, tendré como corpus la obra de tres autores (Tomás Segovia, Ignacio Solares y Enrique Serna), cuya escritura presenta un conjunto de características particulares de ciertas formas discursivas que bien podríamos reunir en torno al fenómeno de la transfiguración narrativa, al cual concibo, en principio, como un proceso de hibridación discursiva originado por el fenómeno de tensión y disolución narrativa al que le acompaña la existencia de un pensamiento teórico-literario encarnado en los pliegues del texto. El problema de la transfiguración narrativa es una suerte de vestíbulo que, considero, permite al lector ubicarse en punto que hace las veces de surtidor de perspectivas: obliga a un reconocimiento de la ausencia-presencia de las estrategias y figuras que intervienen como determinantes en las configuraciones narrativas, y sobre este análisis de la composición y estructura, reclama la incorporación de los otros elementos del texto que escapan al lente narratológico pero que, evidentemente, van expandiéndolo hacia otras esferas que exigen rebasar los lindes textuales.