863 resultados para Substituição tecnológica
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciência da Informação, Programa de Pós-Graduação em Ciência da Informação, 2016.
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A utilização da pólvora negra em Portugal está documentada desde o reinado de D. Fernando, conhecendo-se referências a polvoristas a partir de meados do século XV. De entre as primitivas oficinas da pólvora referenciadas no século XVI, destaca-se a de Barcarena. Com a expansão ultramarina, aumentou a importância desta unidade, o que não obstou a que novas fábricas se fossem instalando em estabelecimentos ultramarinos portugueses, principalmente na índia e no Brasil. Apresenta-se a evolução tecnológica da Fábrica da Pólvora de Barcarena, com especial realce para a monumental fábrica construída por António Cremer (1729) e para as inovações nela introduzidas por Bartolomeu da Costa, nos finais do século XVIII. Referem-se também as posteriores ampliações recebidas pela Fábrica e a utilização de novas formas de energia, a do vapor de água e a energia eléctrica, esta produzida em duas centrais Diesel-eléctricas e numa central hidroeléctrica, instaladas entre 1924 e 1929. Em 1988 encerrou a Fábrica e em 1998 foi criado o Museu da Pólvora Negra de Barcarena, cuja concepção e constituição são sumariamente apresentadas.
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En esta ponencia se proponen algunas ideas para la investigación del impacto, en la vida cotidiana, de la innovación tecnológica y cómo ésta lleva a las personas a una resignificación de la realidad. Se presentan seis dimensiones que son afectadas directa o indirectamente por esta innovación, a saber: la dimensión de las labores domésticas, la laboral, la de la educación formal, el cambio cultural, la ideológica y el proceso de inclusión/ exclusión.
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Español
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Español
Preparação de óxidos mistos de níquel e zinco nanoparticulados a partir de combustíveis alternativos
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The field of "Materials Chemistry" has been developing in recent years and there has been a great increase of interest in the synthesis and chemical and physical properties of new inorganic solids. New routes of synthesis and synthesis modified has been developed with the aim not only to optimize the processes in laboratory scale, but also on an industrial scale, and make them acceptable by current environmental legislation. The phenomenology of current solid state chemistry properties coupled with the high temperature superconductivity, ferromagnetism, porosity molecular and colors are evidence affected by the synthesis method, which in turn can influence the technological application of these materials. From this understanding, mixed oxides of nickel and zinc nanoparticulate were synthesized by microwave-assisted combustion route using three specific types of organic fuels employing the weight ratios 1:1/2 and 1:1 of cation metallic/fuel, in order to investigate the influence of such proportions to obtain the solids. The new fuels were chosen to replace, for example, urea or glycine that are the fuels most commonly preferred in this kind of synthesis. The powders without heat treatment were studied by Thermogravimetric analysis (TGA), X-Ray Diffraction (XRD) and then calcined at 900°C. After heat treatment, the samples were characterized by analysis of X Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The modified synthesis route porposed was effective for obtaining powders. Both the alternative fuels chosen as the different weight ratios employed, influenced in the morphology and obtaining oxides
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El objetivo general de esta investigación consiste en sacar a la luz un conjunto de documentos, los documentos de patentes presentadas en España, sobre un tema concreto, la bicicleta y el ciclismo, y durante un periodo determinado, 1826-1929, presentes en la Oficina Española de Patentes y Marcas (OEPM), organizando esta documentación para su posterior utilización por la comunidad científica. Para ello se han identificado y sistematizado las patentes referidas a la bicicleta, presentadas entre 1826 y 1929, realizando tablas de frecuencia que permitan extraer datos de su incidencia en la invención en el periodo considerado. Ello ha permitido conocer una serie de datos de los inventores, que, en definitiva son los creadores del desarrollo tecnológico en este campo, extrayendo, ordenando y categorizando la información sobre lugar de origen, tipo de inventor (empresa o particular), sexo, práctica de colaboración y profesión. Finalmente se ha estudiado el tipo de inventos, mostrando los sectores en los que se producen las invenciones, identificando si se han puesto en práctica, y determinando aspectos tales como su carácter de invención incremental, su posible consideración como invento raro y curioso, y su coexistencia con una marca registrada. El trabajo se inicia con la introducción seguida de un apartado en el que se presenta el marco teórico en el que se desarrolla la investigación, en una doble vía: en primer lugar el contexto de los documentos de patente, su relación con la innovación y su utilidad como fuentes de información, y en segundo lugar el marco de la invención en el ciclismo, presentando las fases esenciales de la evolución de la bicicleta (capítulo 2). En el marco metodológico (capítulo 3) se explican fuentes y metodología, presentando a continuación el diseño de la investigación, que se resume como sigue: 1- Determinación del universo de datos, 2- Consulta en el Archivo Histórico de la OEPM, 3- Diseño y creación de la base de datos propia, 4- Consulta de los expedientes y toma de imágenes, 5- Tratamiento y análisis de los datos, 6- Búsqueda de información en fuentes para patentes extranjeras, y 7- Consulta a la base de datos de Marcas de la OEPM. El capítulo 4 está dedicado a la investigación propiamente dicha, estructurado en tres grandes bloques. El primero recoge las cuantificaciones tabuladas del total de patentes y el análisis de determinados aspectos generales como la cronología de la invención y diversas comparaciones con resultados obtenidos en otros trabajos. El segundo bloque está centrado en los estudios de solicitantes de patentes, protagonistas de las invenciones. De ellos se contemplan una serie de datos extraídos de los expedientes, y posteriormente tabulados y cuantificados: su procedencia geográfica, su adscripción como empresas o solicitantes particulares, y sus datos de colaboración, finalizando el bloque con un apartado que dedicamos a la innovación femenina, que consideramos una línea de investigación interés. El tercer bloque, el más amplio de todos, está dedicado a la descripción y análisis de los datos referidos a los propios inventos, puesto que es la aplicación de los inventos lo que marca el desarrollo tecnológico de la máquina bicicleta, y su consiguiente evolución histórica y social. Se estructura asimismo en varias secciones. La primera es la más amplia, donde se muestran y explican los datos que tienen que ver con la adscripción de los inventos a sectores temáticos, es decir, que desarrolla las funciones o componentes de la bicicleta que han sido objeto de invención. Los apartados siguientes muestran datos y consideraciones sobre las patentes puestas en práctica, las invenciones incrementales, los inventos curiosos, y las patentes con posible marca registrada de su nombre. Finalmente, las conclusiones del estudio, el establecimiento de posibles líneas abiertas de investigación, la relación de fuentes consultadas y los anexos cerrarán la exposición de esta tesis. ABSTRACT The main goal of this research thesis is to shed light on a specific documentary record: patents presented in Spain, regarding a specific theme: bicycles and cycling, within a given period: 1826-1929. This record is organized for the ulterior use by the scientific community. In order to carry out this goal, the mentioned patents have been identified and systematized, and analyzed for frequency in order to infer the incidence of its invention in the period under consideration. This has brought to light some information on the inventors which are, after all, the creators in the technological development of that field. Their bibliographical information: origin, type of inventor (company or individual), gender, collaboration behavior and profession. Finally, the type of inventions has been studied, showing the sectors in which inventions are produced, whether these were transferred to practice, and other key information like the incremental nature of their invention, their possible consideration as ‘rare or curious invention’, and their coexistence with a registered trademark. This thesis is organized with an initial introduction, after which a section outlines the theoretical framework for the research along two axes: first the context of the patent documents, their relation with innovation and their usefulness as information sources; second, the invention of cycling and the development phases of bicycles. In the methodological section the sources and methodology are explained and reasoned, followed by the research design: 1-determination of the data universe, 2-consultation at the historical archive of the OEPM (National Patent Office), 3-design and creation of a database, 3-analysis of the files and image catchment, 5-treatment and analysis of data, 6-browsing of source information for foreign patents, and 7-consultation of the trademark information at the OEPM. Chapter 4 is dedicated to research itself, in three main sections. The first one has the quantification of the patent total in tables and the analysis of specific overall chronological aspects of the invention, and some comparisons with the results obtained in other research. The second section is centered on the studies of patent requests and inventors. Some data extracted from the files has been systematized: geographical origin, adscriptions as companies or individuals, and their collaboration data, ending with a sub-section on women’s invention, which we consider an interesting research line. The third section, the biggest one of them all, is dedicated to the description and analysis of the data referred to the inventions themselves, because it is the application of the inventions which constitutes the technological development of the bicycle, and therefore its historical and social evolution. It is also structured in various sub-sections. The first one is the longest one, with information regarding the thematic typology of the inventions: functions and bicycle components which are innovated. The other ensuing subsections study patents which were actually incorporated and used, incremental inventions, curious inventions and patents with possible associated trademarks. Finally, the study conclusions, the establishment of lines of potential further research, the references used, and the annexes which culminate the thesis exposition.
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Over recent years the structural ceramics industry in Brazil has found a very favorable market for growth. However, difficulties related to productivity and product quality are partially inhibiting this possible growth. An alternative for trying to solve these problems and, thus, provide the pottery industry the feasibility of full development, is the substitution of firewood used in the burning process by natural gas. In order to contribute to this process of technological innovation, this paper studies the effect of co-use of ceramic phyllite and kaolin waste on the properties of a clay matrix, verifying the possible benefits that these raw materials can give to the final product, as well as the possibility of such materials to reduce the heat load necessary to obtain products with equal or superior quality. The study was divided into two steps: characterization of materials and study of formulations. Two clays, a phyllite and a residue of kaolin were characterized by the following techniques: laser granulometry, plasticity index by Atterberg limits, X-ray fluorescence, X-ray diffraction, mineralogical composition by Rietveld, thermogravimetric and differential thermal analysis. To study the formulations, specifically for evaluation of technological properties of the parts, was performed an experimental model that combined planning involving a mixture of three components (standard mass x phyllite x kaolin waste) and a 23 factorial design with central point associated with thermal processing parameters. The experiment was performed with restricted strip-plot randomization. In total, 13 compositional points were investigated within the following constraints: phyllite ≤ 20% by weight, kaolin waste ≤ 40% by weight, and standard mass ≥ 60% by weight. The thermal parameters were used at the following levels: 750 and 950 °C to the firing temperature, 5 and 15 °C/min at the heating rate, 15 and 45min to the baseline. The results showed that the introduction of phyllite and/or kaolin waste in ceramic body produced a number of benefits in properties of the final product, such as: decreased absorption of water, apparent porosity and linear retraction at burn; besides the increase in apparent specific mass and mechanical properties of parts. The best results were obtained in the compositional points where the sum of the levels of kaolin waste and phyllite was maximal (40% by weight), as well as conditions which were used in firing temperatures of 950 °C. Regarding the prospect of savings in heat energy required to form the desired microstructure, the phyllite and the residue of kaolin, for having small particle sizes and constitutions mineralogical phases with the presence of fluxes, contributed to the optimization of the firing cycle.
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Doutoramento em Finanças
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Al analizar la problemática del desarrollo, hay coincidencia de que el estilo de desarrollo que se viene aplicando en las últimas décadas en los países subdesarrollados, no lleva a la sostenibilidad, pues no logra la satisfacción de las necesidades de amplios sectores de la población que viven en situación de pobreza, y porque se viene generando un cada vez más evidente daño ambiental.También podría afirmarse que hay algún consenso en la afirmación de que los países en desarrollo difícilmente lograrán el desarrollo sostenible sin un crecimiento sostenido de la actividad económica.Sin embargo, no se puede afirmar que por sí mismo el crecimiento económico pueda llevar a la satisfacción de necesidades presentes y futuras y al mejoramiento de la calidad ambiental. Así, el crecimiento podría considerarse como un requisito necesario, pero nunca como un mecanismo suficiente para la sostenibilidad.
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95 p.
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Os betões atuais são materiais com custos extremamente competitivos devido ao baixo custo do cimento Portland. Contudo, os elevados níveis de emissões de C02 gerados na sua produção provocam o aumento do custo final do produto, tanto económico como ambiental. Devido a esta situação algumas adições têm sido estudadas como alternativas para substituir parcialmente os conteúdos de cimento no fabrico de betão. Uma vez que existem grandes quantidades de pó de mármore inutilizadas na região de Évora decidiu-se avaliar o seu comportamento. O pó de mármore foi adicionado em certas percentagens de forma a reduzir os conteúdos de cimento, permitindo avaliar se este iria manter e/ou melhorar as características de resistência à compressão e trabalhabilidade do betão. Além de avaliado o comportamento desta adição, o mesmo foi também comparado com a adição de filer calcário nas mesmas percentagens. Os resultados obtidos demonstraram a exequibilidade da utilização de ambas as adições. ABSTRACT: Concretes currently used in construction are materials with very competitive costs due to the low cost of Portland cement. However, high levels of C02 emissions generated in its production cause an increase of the final cost of the product, both economically and environmentally. Due to this situation, some additions have been studied as alternatives to replace partially cement contents in concrete production. Since there are large quantities of marble dust in the region of Évora, it was decided to evaluate his behavior. The marble dust was added in known percentages so the cement contents could be reduced, allowing evaluating if it will maintain and/or improve the characteristics of the compressive strength and workability of the concrete. ln addition to evaluating the behavior of marble dust, this addition was also compared with the addition of limestone filler in the same percentages. The results demonstrated the feasibility of using both additions.
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The sharp consumption of natural resources by the construction industry has motivated numerous studies concerning the application of waste to replace partially or fully, some materials, such as aggregates, thereby reducing the environmental impact caused by the extraction of sand and crushing process. The application of stone dust from crushing process arising as an aggregate for the production of Portland cement concrete is a viable alternative in view of the high cost of natural sands, in addition to the environmental damage which causes its operation to the environment. The stone dust has reduced cost compared to natural sand because it is produced in the beds of their own quarries, which are usually located close to major urban centers. This study examined the feasibility of using stone dust from the crushing of rock gneisses in the state of Bahia, replacing natural quartz sand. In the development of scientific study was conducted to characterize physical and chemical raw materials applied and molded cylindrical specimens , using as reference values Fck 20, Fck 25 and Fck 30 MPa ( resistance characteristic of the concrete after 28 days) in following compositions stone powder: 10%, 30%, 50 %, 100% and 100% with additive. The specimens were cured and subjected to the tests of compressive strength and water absorption, then the samples were subjected to the tests of X-ray diffraction and scanning electron microscopy. The results obtained showed that the composition with 10% stone powder showed the best results regarding the physical and mechanical tests performed, confirming the reduction in compressive strength and increased water uptake increased as the content of the powder stone in the concrete composition
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2007