Estudo de ciclos limites em uma classe de equações diferenciais descontínuas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise da efetividade de polimerização, adaptação marginal e interna de restaurações Classe II de resinas compostas de inserção em bloco utilizando diferentes matrizes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Usinagem do alumínio da classe 6005 com uso de ferramenta cerâmica

The machining process is so much important in the economic world. Many machining parameters have been studied to maximize results, in terms of cost and lifetime. (decrease of cutting tool wear, improved surface finish, among others). The objective of this study is to evaluate the wear of a ceramic tool in the machining of the aluminum alloy 6005 A. The analysis of the wear of the cutting tools is very important due to its big impact on the final finishing of the piece as a whole. The evaluation took place in two stages, first it was done a detailed study of the literature of the whole machining process, where the study of the formation and swarf classification were among the most important steps in this phase. The second step consisted in the machining of the piece of aluminum 6005 A with a ceramic cutting tool constituded of aluminum oxide and magnesium oxide with silicon carbide impregnation. The swarf generated in this process was then photographed with a Zeiss optical microscope and analyzed for its size and shape. Through this comparison it was concluded that the swarf are generated shear swarfs, shaped like a tangled, fragmented and arcs connected, thus classifying the material as medium difficulty machining. Through the image analysis tool it was concluded that the parameter of lower wear was the: Vc = 500m / min, f = 0.10mm / rev and ap = 0.5mm

Torneamento da liga de alumínio da classe 6005 utilizando ferramenta cerâmica

Machining processes are one of the most important manufacturing processes in the modern world. In these processes, there are many elements which will influence in the final result of the machined part. Among them, the tools are the principal factor of the rising cost, because its global influence on the process. In aeronautical industries, this can be more evidenced due the need to machining several alloys, between them, aluminum alloys. These alloys have to demonstrate a specific surface finishing to be used in aircraft's fuselage. This kind of industry is one of the segments which is still rising in Brazil, and they are looking viable alternatives in the manufacturing processes of materials, due the need to produce more and more parts and equipment, with costs increasingly reduced. The purpose of this project is the development of a ceramic with differentiated properties. The ceramics were developed using a pre-sintering at 1200 °C, with posterior sintering at 1600°C, and subjected to dry turning process on aluminum alloy 6005. The characterizations showed that ceramics presented with toughness on the center of 1700 MPa and on the surface of 1950 MPa, density 98,5 ±0,14. g/cm³. Ceramics were grinded and faceted, according to ISO standard 1832, and subjected to turning tests in a ROMI lathe brand, model GL240M, using cutting speeds of 500, 800 and 1000 m/min with different feed rates. The machining results showed low occurrence of flank wear to all cutting speeds, and better surface finishing average values of Ra = 0,4935 μm and Rt = 8,112 μm. In general, it could be seen that the tool presents important potential to machining 6005 alloy, and that the use of correct parameters can decrease and/or eliminate subsequent processes, providing important reductions in costs related to the machining processes

Avaliação imediata e após 6 meses da resistência de união a dentina de restaurações de resina composta classe I in vivo e in vitro

Pós-graduação em Odontologia Restauradora - ICT

Usinagem do alumínio da classe 6005 com uso de ferramenta cerâmica

The machining process is so much important in the economic world. Many machining parameters have been studied to maximize results, in terms of cost and lifetime. (decrease of cutting tool wear, improved surface finish, among others). The objective of this study is to evaluate the wear of a ceramic tool in the machining of the aluminum alloy 6005 A. The analysis of the wear of the cutting tools is very important due to its big impact on the final finishing of the piece as a whole. The evaluation took place in two stages, first it was done a detailed study of the literature of the whole machining process, where the study of the formation and swarf classification were among the most important steps in this phase. The second step consisted in the machining of the piece of aluminum 6005 A with a ceramic cutting tool constituded of aluminum oxide and magnesium oxide with silicon carbide impregnation. The swarf generated in this process was then photographed with a Zeiss optical microscope and analyzed for its size and shape. Through this comparison it was concluded that the swarf are generated shear swarfs, shaped like a tangled, fragmented and arcs connected, thus classifying the material as medium difficulty machining. Through the image analysis tool it was concluded that the parameter of lower wear was the: Vc = 500m / min, f = 0.10mm / rev and ap = 0.5mm

Torneamento da liga de alumínio da classe 6005 utilizando ferramenta cerâmica

Machining processes are one of the most important manufacturing processes in the modern world. In these processes, there are many elements which will influence in the final result of the machined part. Among them, the tools are the principal factor of the rising cost, because its global influence on the process. In aeronautical industries, this can be more evidenced due the need to machining several alloys, between them, aluminum alloys. These alloys have to demonstrate a specific surface finishing to be used in aircraft's fuselage. This kind of industry is one of the segments which is still rising in Brazil, and they are looking viable alternatives in the manufacturing processes of materials, due the need to produce more and more parts and equipment, with costs increasingly reduced. The purpose of this project is the development of a ceramic with differentiated properties. The ceramics were developed using a pre-sintering at 1200 °C, with posterior sintering at 1600°C, and subjected to dry turning process on aluminum alloy 6005. The characterizations showed that ceramics presented with toughness on the center of 1700 MPa and on the surface of 1950 MPa, density 98,5 ±0,14. g/cm³. Ceramics were grinded and faceted, according to ISO standard 1832, and subjected to turning tests in a ROMI lathe brand, model GL240M, using cutting speeds of 500, 800 and 1000 m/min with different feed rates. The machining results showed low occurrence of flank wear to all cutting speeds, and better surface finishing average values of Ra = 0,4935 μm and Rt = 8,112 μm. In general, it could be seen that the tool presents important potential to machining 6005 alloy, and that the use of correct parameters can decrease and/or eliminate subsequent processes, providing important reductions in costs related to the machining processes

Avaliação imediata e após 6 meses da resistência de união a dentina de restaurações de resina composta classe I in vivo e in vitro

Pós-graduação em Odontologia Restauradora - ICT

Estabilidade em longo prazo do tratamento da má oclusão de classe II, divisão 1, com a utilização de um aparelho funcional propulsor mandibular fixo: relato de caso

O tratamento da má oclusão de Classe II sem extrações dentárias vem ganhando popularidade na comunidade ortodôntica já há três décadas. Aparelhos funcionais fixos vêm sendo utilizados por profissionais, de maneira crescente, para promover compensações dentoalveolares e corrigir a má oclusão de Classe II. Os efeitos mais significativos são observados em pacientes com padrão de crescimento horizontal. Um caso clínico será relatado com o uso do aparelho fixo Twin Force Bite Corrector em uma paciente do sexo feminino, para a correção da Classe II. Esse dispositivo de ancoragem fixa dispensa o uso de aparelhos funcionais removíveis e não necessita da cooperação do paciente.

Temposfuturos - Vidas secas, de Graciliano Ramos

Vidas secas (1938) é o último romance de Graciliano Ramos, escrito depois da experiência do autor nos cárceres do Estado Novo, experiência por ele mesmo julgada essencial para a elaboração do livro. O artigo começa pela discussão acerca do sentido das exigências éticas e estéticas do romancista. Procura descrever a organização do romance a partir da combinação de contos, originalmente autônomos. Examina em seguida o episódio "Baleia", onde se discute o problema da domesticação e da educação. Termina com a análise da tensão entre a fala da utopia e o realismo crítico.

O mundo coberto de penas Família e utopia em Vidas secas

O texto analisa a trama dos sonhos, dos desejos e da realidade de uma família de retirantes nordestinos que, tratados como bichos, sonham um dia fazer valer sua condição de homens. Embora atravessada pela dúvida e pela incerteza impostas pelos obstáculos de uma realidade desumana, a narrativa fala também da persistência de sonhos e desejos que não deixa morrer a esperança utópica dos personagens e do próprio autor, ainda que vaga, do advento de um mundo humanizado.

Classe hospitalar: a articulação da saúde e educação como expressão da política de humanização do SUS

A saúde é determinada por condições sociais, econômicas, educacionais, políticas e ambientais, extrapolando, portanto, a dimensão exclusivamente biológica. O presente trabalho tenta estabelecer uma reflexão interpretativa sobre os princípios do SUS e mostrar a interface deles com a proposta da classe hospitalar, uma modalidade de educação especial que estimula a construção de conhecimentos, a capacitação e o ensino de algumas habilidades, contribuindo para o desenvolvimento infantil. Tratase de um exercício de argumentação para o entendimento do papel da classe hospitalar na realização da atenção integral à saúde no Brasil. O desenvolvimento de atividades pedagógico-educacionais em hospitais permite oferecer às crianças e adolescentes hospitalizados a continuidade do seu aprendizado.