Rietveld analysis of mechanically activated BaCO(3)-TiO(2) system

BaTiO(3) powders were prepared through mechanical activation chemistry and analyzed by Rietveld refinement with X-ray diffraction data. Raw BaCO(3) and TiO(2) powders were dry milled for 5 and 20 h and then calcinated for 2 and 4 h at 800 degrees C. The milling process was found to have broken up the BaCO(3) and TiO(2) crystals into smaller crystals and formed only small amounts ( 1.5 wt%) of BaTiO(3). Subsequence calcinations for 2 and 4 h at 800 degrees C successfully produced large amounts (>97.7 wt%) of BaTiO(3) crystals. The calcination process also generated microstrains and crystallite-size anisotropy in BaTiO(3). An increase in the calcination time from 2 to 4 h increased the BaTiO(3) weight percentage and the crystal lite-shape anisotropy, but decreased the tetragonal distortion anisotropic microstrains in BaTiO(3) crystals. (C) 2008 International Centre for Diffraction Data.

Teatro e a dialética das linguagens: Cia Teatral Bumba Meu Baco

Este trabalho é centrado na análise específica das vivências teatrais do grupo “Cia. Bumba meu Baco”, projeto reconhecido pela PROEX desde 2006, do Campus da UNESP de Rio Claro. Desta forma, utiliza-se das experiências vividas pelo grupo durante todo o período de sua criação até o presente momento, para demonstrar como a linguagem teatral trata de assuntos da ciência geográfica e como ela pode chegar a gerar discussões e resultados no âmbito geográfico. Para isso, analisa-se em um primeiro momento a evolução da companhia, que ao longo dos anos pesquisou e trabalhou diferentes temas chegando ao seu trabalho mais relevante no ano de 2009, que utilizou como um dos métodos o teatro épico de Bertolt Brecht. Com o cunho político e social que possui, tal método ajudou o grupo a expandir a relação entre arte cênica e temas em geografia humana, além de gerar outros acréscimos a todos os que participaram direta e indiretamente deste processo

O uso do material manipulativo Tangram e de jogos como estratégias de motivação para a aprendizagem de frações

In this research, we analyzed the use of manipulative materials and games as motivators tools that facilitate the comprehension of fractions content when presented to a class of students from the 9th grade from a public school in Guaratinguetá-SP city. The students are 14 and 17 years old. Initially we presented the benefits that could bring manipulative materials for teaching and learning with understanding, followed by historical accounts of the Tangram material. We show the advantages of the games, when properly used in activities classroom. The game titled Dominoes fractions using the Tangram was applied in order to check if students retook properly the fractions contents. This research was motivated students to participate in math classes and this motivation may have promoted the understanding of the contents worked

Chelating agent effects in the synthesis of mesoscopic-size superconducting particles

Several routes and procedures have been used in these last years as an effort to achieve single-phase mesoscopic-size superconducting samples. In this paper, the effects of using citric acid (CA), tartaric acid (TA) and ethylenediaminetetraacetic acid (EDTA) as chelating agents and ethylene-glycol (EG) as polyhydroxy alcohol were studied in order to establish conditions to avoid the occurrence of BaCO(3) undesirable secondary phase in YBa(2)Cu(3)O(7-delta) (YBCO). Thermal evolution of intermediate compounds formed during the calcinations process by the use of different chelating agents was traced using thermogravimetric and spectroscopic methods. The obtained results indicated that the polymer breakdown of samples prepared using EDTA occurs at higher temperatures than others chelating agents and also reduces the occurrence of BaCO(3) secondary phase as studied by X-ray diffraction measurements. Furthermore, the magnetic response of the mesoscopic-size YBCO specimens obtained was verified showing that samples present different superconducting response.

Intense blue and green photoluminescence emissions at room temperature in barium zirconate powders

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Microwave-hydrothermal synthesis of barium strontium titanate nanoparticles

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

Barium titanate screen-printed thick films

Barium titanate (BT) thick films were prepared from mechanically activated powders based on BaCO(3) and TiO(2). After homogenization and milling in a high-energy vibro mill, the powders were calcined at 700 degreesC for 2 h by slow heating and cooling rates. A thick film paste was prepared by mixing BT fine powders with small amount of low temperature sintering aid and organic binder. The thick films were screen-printed on alumina substrates electroded with Ag-Pd. The BT films were sintered at 850 degreesC for 1 h. The thickness was 25-75 mum depending of number of layers. The microstructure of thick films and the compatibility between BT layers and substrate were investigated by SEM Results of dielectric property measurements are also reported. (C) 2002 Elsevier B.V. Ltd and Techna S.r.l. All rights reserved.

Screen printed barium titanate thick films prepared from mechanically activated powders

Barium titanate thick films were prepared from mechanically activated powders based on BaCO 3 and TiO 2. The thick films were screen-printed on alumina substrates electroded with Ag/Pd. The BT films were sintered at 850°C for 1 hour. The thickness was 30-75 μm depending of number of layers. The microstructure of thick films and the compatibility between BT layers and substrate was investigated by SEM. The dielectric properties were measured and the results were reported.

Usabilidade na web: o usuário como agente-facilitador no desenvolvimento de interfaces de home pages

Pós-graduação em Design - FAAC

Os títulos de crédito eletrônico e a execução da duplicata virtual

Pós-graduação em Direito - FCHS

Pavimentações do plano: um estudo com professores de matemática e arte

Pós-graduação em Educação Matemática - IGCE

Fatores de crescimento e citocinas envolvidos na angiogênese de melanoma em animais selecionados pela intensidade da resposta inflamatória aguda

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Cuidado de si e a educação matemática: perspectivas, reflexões e práticas de atores sociais (1925-1945)

Pós-graduação em Educação Matemática - IGCE

Efeitos da terapia manual de Maitland em pacientes com lombalgia crônica

Introduction: The low back pain are a problema of health. Objective: to evaluate the effects of the Maitland´s manipulation in pain, fl exibility, functional capacity and quality of life of the patients with chronic low back pain. Method: Sxteen subjects, of both genders, with the age from 23-68 years old (48.69,± 11.61 years old) were evaluated by test sit and reach (TSA), Visual Analogue Scale (VAS) and answered the questionnaires of the quality of life Medical Outcomes Study 36- Item Short-Form Health Survey (SF-36) and the Roland-Morris Disability functional incapacity (RMDQ). The treatment was carried out twice a week, totaling 10 sessions. Each session lasted 30 minutes and consisted by Maitland´s techniques, applied as the symptoms evaluated at the beginning of each session. After 10 session, the subjects were re-evaluated. The data obtained in the assessments concerning the TSA and VAS were analyzed by Student t test, the data relating to the questionnaire were analyzed using the Wilcoxon non-parametric statistics test. For the interpretation was used signifi cance level of 5% (p≤0,05). Results: A signifi cant improvement was in the intensity of pain, disability, fl exibility and quality of life. Conclusion: The Maitland´s therapy showed effective, which suggests be an appropriate strategy for intervention for patients with chronic low back pain.

Estudo exploratório sobre o desempenho em aritmética utilizando o soroban como ferramenta auxiliar

Pós-graduação em Matemática em Rede Nacional - IBILCE