1000 resultados para FÍSICA DO ESTADO SÓLIDO


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Solid-state compounds of general formula LnL3.nH2O, in wich Ln represents lanthanum, lanthanides and yttrium, L is ketoprofen, and n = 0,5 (Pr, Sm, Tb), 1 (La, Eu, Dy, Ho, Er, Tm, Lu) e 1,5 (Ce, Nd, Gd, Yb, Y) were synthesized. Simultaneous thermogravimetry-differential analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and EDTA complexometry were employed to characterize these compounds. The TG-DTA and DSC curves provided information concerning the thermal behaviour and thermal decomposition of synthesized compounds. The experimental and theoretical infrared spectroscopic data suggested that ketoprofen acts as a bidentate ligand towards trivalent lanthanides and yttrium (III)

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In this study, the drug indomethacin, a non-steroidal anti-inflammatory indoleacetic acid derivative and the complex of indomethacin and lanthanum (III) in solid form were synthesized and characterized by Thermogravimetry (TGA), Differential Thermal Analysis (DTA), Differential Scanning Calorimetry (DSC) and powder X-ray diffractometry (XRD), infrared vibrational spectroscopy by diffuse reflectance (FTIR) and complexometric titration with EDTA. With the TG curves it was possible to determine the stoichiometry of the complex as La(Ind)3·3.5H2O where Ind is the drug indomethacin. The result of thermal analyzes provided information on the thermal stability, enthalpy of dehydration and thermal behavior of the compounds. The infrared spectrum and with the aid of theoretical calculations suggests that the indomethacin is coordinated by the carboxylate group in the bidentate mode

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This Final Paper had as it main goal to make a thermoanalytical study of lighter trivalent lanthanides (Lanthanum, Cerium, Praseodymium, Neodymium, Samarium and Europium) with the Ibuprofen ligand (nonsteroidal anti-inflammatory) that have a general formula LnL3.nH2O, on solid state, where Ln are the Lanthanides, L is the Ibuprofen ligand and n = number of water molecules of hydration that went from 1,0 to all the compounds. In order to characterize this compounds, it has been used the thermoanalytical techniques TG-DTA (thermogravimetry - Diferential Thermal Analysis) and DSC (Diferential Scanning Calorimetry), Fourier transformed infrared spectroscopy (FTIR) and complexometric titration with EDTA. Through the TG-DTA technique, it has been possible to set the thermal stability of the compounds, the number of thermal decomposition steps and temperatures that ocurred that also provided stoichiometry to the synthesized compounds. The DSC technique has shown the enthalpy of dehydration of the samarium and europium compounds, it was not possible to see it in the other compounds due to a endothermic peak on the DSC curve not being formed. In the case of neodymium, a thermal event ocurred, in which it could be a oxidative decarboxylation right after the dehydration. The infrared was utilised to study the carboxilate groups streches, and so, suggest a ligand metals compound coordination, that to this present paper has been a bidentade bridged coordenation. At last, the complexometric tritation was used to very the ammount of metal present in each compound, and so, verify if the proposed stoichiometry was according to the theory

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The study of ceramic materials is constantly evolving, especially in research related to advanced ceramics. Once these have many applications, this paper relates to synthesis by solid state reaction of calcium copper titanate (CCTO) ceramic material means doping with strontium. The powders were characterized using thermal analysis techniques such as TG (thermogravimetry), DTA (differencial thermal analysis), dilatometry, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The compositions have submitted weight loss at around 6% with respect to carbonates used, and was attributed a temperature of 950° C to perform the calcination according to thermogravimetric analysis. After the process of calcination and milling, the particles presented approximately spherical shapes and high percentages of substitution Ca2+ with Sr2+ was evident by the presence of necks between to particles due to the milling calcination. Analyses with Energy Dispersive Spectroscopy (EDS) showed stoichiometries in different samples very similar to the theoretical stoichiometry

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O atual cenário do ensino da Educação Física no Brasil caracteriza-se como um complexo campo de conflitos, no qual emergem e embrenham-se diferentes proposições teórico-metodológicas, originadas desde meados da década de 1980 no processo histórico de emancipação, superação e ressignificação da Educação Física. Tais concepções, em contraposição ao criticado e tradicional ensino técnico-esportivista, propõe que na escola os conteúdos abordados deveriam propiciar a apropriação crítica e autônoma das diversas manifestações da Cultura de Movimento. Sendo assim, cabe analisar como os professores, autores e não meros aplicadores, lidam com mudanças curriculares. É primordial analisar criticamente as práticas pedagógicas dos professores que vivenciam e implementam tais mudanças curriculares. O objetivo desta pesquisa foi investigar como se caracteriza a relação saberes docentes-ensino de lutas entre professores da rede pública estadual de São Paulo, no cenário de implementação do currículo oficial de Educação Física. Foi realizado um estudo de natureza qualitativa; os dados foram coletados por meio de entrevistas semi-estruturadas com professores e professoras atuantes na rede pública. Os resultados evidenciaram que o déficit na formação inicial dos professores, contribuiu para o trato pedagógico superficial do conteúdo lutas em suas aulas. Com isso, dificultando o desenvolvimento do conhecimento pedagógico do conteúdo dos docentes, que atribuem sua principal fonte de conhecimentos sobre o tema a recortes oriundos da influência midiática e da proposição de atividades a partir do Currículo de Educação Física do Estado de São Paulo. Percebemos aqui, a importância da construção do conhecimento pedagógico do conteúdo, para o desenvolvimento da base de conhecimentos do educador. Acreditamos, conforme Shulman, que é de suma importância que o professor/a domine uma base de...

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Athletics in most of its history, turned to competition, giving it little pedagogical knowledge, prevailing knowledge grounded in records, indexes and competitions. Thus, although it is considered a classic content of Physical Education, this modality is still not widespread in schools. The present study aimed to investigate possible progress in the teaching and learning of athletics in the State Schools of Bauru from the implementation of the Curriculum of the State of São Paulo for Teaching Physical Education. We attempted to checking the perspective of teachers and students, the changes in teaching and learning as well as difficulties encountered from the deployment. To that end, we conducted survey of the theoretical and practical alternatives developed by Physical Education teachers, about athletics theme, since the implementation of the Curriculum of the State of São Paulo for the Teaching of Physical Education in 2008, in seven (7) state schools in Bauru-Sao Paulo, randomly chosen, prioritizing different regions of the county. There was the purpose of investigating, through questionnaires, interviews (applied to teachers and students), what progress has been achieved with regard to the approach of collegiate athletics in the teaching/learning process, if there are difficulties, what are these and how they could be addressed in order to improve teaching and learning in school athletics. The collected data were analyzed comparatively, before and after implementation of the Curriculum of the State of São Paulo for Physical Education, gathering and specifying negative and/or positive aspects raised by teachers and students. It was concluded that the students' knowledge of the sport has increased, but the practice of sport is still far from being normal to them, doing so is necessary to include content from the earliest school years. Teachers attribute the greatest difficulties to lack of infrastructure and materials suitable for this...

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Amilases e proteases constituem um dos principais grupos de enzimas industriais pelo seu amplo espectro de aplicações biotecnológicas. Elas podem ser obtidas a partir de fontes microbianas e com altos rendimentos por processos de fermentação em estado sólido (FES). Conhecer as características bioquímicas das enzimas é fundamental para adequação aos processos industriais. O objetivo do trabalho foi determinar a melhor temperatura para atividade das enzimas amilase e protease de Rhizopus oligosporus obtidas por fermentação em estado sólido utilizando farelo de trigo como substrato. Os melhores valores para atividade amilolítica e proteolítica foram obtidos nas temperaturas de 55 - 65 °C e de 50 - 60 °C, respectivamente. Estes resultados sugerem que as enzimas estudadas podem ser utilizadas em processos que empregam elevadas temperaturas.

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