Materials Physics
Mostrando 25-36 de 76 artigos, teses e dissertações.
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25. Estudo sistemático do freamento de íons pesados em sólidos no regime de baixas velocidades / Systematic study of heavy ions stopping in solids at the low velocity regime
The energy loss of ions in materials is an important issue not only because of its direct applications on material analysis techniques, but also for the understanding of the interactions. Accurate knowledge of heavy ion stopping power at low energies is necessary in materials science as well as in basic physics, e. g. in the Doppler Shift Attenuation Method
Publicado em: 2009
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26. DEVELOPING A VERSATILE MONOCHROMATIZATION SYSTEM FOR X-RAYS / DESENVOLVIMENTO DE UM SISTEMA DE MONOCROMATIZAÇÃO VERSÁTIL PARA RAIOS-X
The investigation of the dynamics of the interaction of high-energy X-rays and molecules of biological interest requires the energy of the X-rays to be well defined, so that one can establish the dependence of the molecular ionization and fragmentation patterns as functions of the incident beam energy. For this purpose, a versatile system for the monochromat
Publicado em: 2009
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27. CARACTERIZAÇÃO DE DEFEITOS MECÂNICOS PRODUZIDOS POR NANOINDENTAÇÃO NO INP / CHARACTERIZATION OF MECHANICAL DEFECTS PRODUCED BY NANOINDENTATION IN INP
In this thesis, the mechanical deformation mechanism of semiconductors III-V was studied, especially for InP. Defects were produced by indentations using an atomic force microscope and a Triboscope nanoindenter. The AFM tip torsion during indentation difficult the control and the reproducibility of AFM nanoindentation experiments. Nevertheless, the tip torsi
Publicado em: 2009
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28. Purificação de silicio metalurgico por fusão zonal horizontal em forno de feixe de eletrons / Purification of metallurgical silicon by horizontal zone melting in an electron beam furnace
The search for renewable energy sources has caused a boom in the production of solar cells in this decade, which rose from 0.3 GW in 2002 to 6.0 GW in 2008, totaling 37 billion dollars in 2008. The production of Electronic Grade Silicon (SiGE) increased 127% from 2007 to 2008, and approximately 90% of solar cells produced nowadays use SiGE, which is responsi
Publicado em: 2009
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29. Trends in academic research on the science education in elementary school (1972-2005) / Tendencias da pesquisa academica sobre o ensino de ciencias nas series iniciais da escolarização (1972-2005)
Considering the incipient spread of researches on the Science education in Brazil and its recognized potential for the improvement of the school teaching, in special in elementary school, the inquiry describes and analyses the tendencies of the theories and dissertations directed to the Science education in elementary school in the period from 1972 to 2005.
Publicado em: 2009
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30. Radioatividade de rochas provenientes das formações geológicas pertencentes à bacia hidrográfica do Rio Tibagi
This work is a study of the 40K and the 238U and 232Th series radioactivity in rocks measured with high resolution gamma ray spectrometry. The rocks were taken from the geologic formations in the region of the Tibagi river hydrographic basin. The course of this river cuts through the Paleozoic and Mesozoic stratigraphic sequences of the Paraná sedimentary b
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/08/2008
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31. Construcción y caracterización de un tubo Ranque-Hilsch
The phenomenon of temperature distribution in a rotating gas flow is known as the Ranque-Hilsch effect. The Ranque-Hilsch tube (R-H ) is a system that in absence of movable parts separates an air flow in two portions, cold and hot ones. In this work a R-H tube is constructed using low cost pieces. We showed that effect is dependent of some of its parameters
Revista Brasileira de Ensino de Física. Publicado em: 2008-12
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32. Estudio experimental de láminas de vidrio en voladizo
The beams deflection is an important subject in physics and engineering courses to study the elastic properties of a great variety of industrial materials . In this work the experimental deflection of thin glass sheets in cantilever is presented. The deflection test is realized putting weights on the free extreme of glass sheets, in order to determine the de
Revista Brasileira de Ensino de Física. Publicado em: 2008
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33. Estudo dos mecanismos responsáveis pela passivação de metais: cobre / Study of the respnsible mechanisms for the metal´s passivation: cooper
è estuda a cinética de oxidação de filmes finos de cobre e os mecanismos envolvidos em sua passivação através de; implamtação iônica, formação de ligas e utilização de uma camada protetora.
Publicado em: 2008
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34. Caracterização fisico-química de adobe estabilizado com amido de mandioca
Due to the high habitational Brazilian shortage, traditional technologies of earth construction and constructive elements production have been rescue, having the soil as a principal raw material. Between these traditional technologies, there are the adobes, which consist of soil blocks with regional variable size. The soil material is removed, humidified, tr
Publicado em: 2008
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35. Formulação e caracterização de matérias-primas para revestimento cerâmico Semi-Poroso com adição de chamote de telhas / Formulation and characterization of raw materials for Semiporous ceramic coating and roofing tile Chamote
The ceramics industry in Piauí is nowadays with 55 industries where 11 are in Teresina which is the mainstream of the state, producing 55 million shingles; in which 10 % is of this production is wasted being sometimes thrown on the margins of rivers, roads and highways provoking an environmental degradation. The main goal of this work is to verify the poten
Publicado em: 2008
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36. Análise sub-ppm de flúor em água pela técnica PIGE / SUB-PPM analysis of fluorine in water by the Pige technique
This work presents a new method for the analysis of fluorine in water, at the tenth of ppm concentration level, based on the PIGE (Particle-Induced Gamma-ray Emission) technique. It is shown that determination of concentrations of this order of magnitude by PIGE requires the use of a preconcentration method. Some attempts of preconcentration of fluorine by a
Publicado em: 2008