932 resultados para Feições estruturais


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This paper studies the frame deformations on a formula SAE vehicle in steady-state cornering and its influence on the lateral load transfers and, consequently, on the tires normal loads due to the applied lateral load. For a vehicle with a perfect rigid frame, the vehicle mass, the position of the center of gravity and the suspensions are the only factors responsible for the load distribution between the tires. When the frame deformations are no longer negligible, the frame deformations affect the loaddistribution between the tires. The frame flexibility turns it able to behave as an additional set of springs to the suspension system, thus changing the behavior of the set. This paper describes howit happens and suggests ways to minimize this phenomenon

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The study of physical and mechanical properties of wood is essential for its structural use and it is of great importance to the construction industry. Thus, this study aimed to determine the physical and mechanical properties of the wood Amaru - a hybrid of Eucalyptus, developed by Plantar Projects and Forest Products Ltda. In order to determine the properties of Amaru, round samples were used, which were provided to the Laboratory of Wood and Wooden Structures of the School of Engineering of São Carlos, University of São Paulo - LaMEM / EESC / USP. For the characterization of the physical properties, the apparent specific gravity and moisture content of the samples were determined. To the mechanical characterization, the following properties were evaluated: strength and stiffness in compression, strength and stiffness in bending, shear and tension. The procedures of the tests performed in this study were done according to the recommendations of the Brazilian Wood Standard ABNT NBR 7190:1997. The specimen used were confectioned in actual dimensions, according to as those used in the construction system proposed by Plantar. The results obtained from the tests performed showed that the mechanical properties approached the values proposed by the Wood Standard NBR 7190. The visual grading was important to provide a primary idea about the failure modes to be obtained from the tests performed. The bending test showed the modulus of elasticity (MOE) and Modulus of Rupture (MOR), which resulted in 15822 MPa and 101,7 MPa, respectively. The compression test resulted in values Ec0,m and fc0, 15698 MPa and 50,7 MPa. The tensile strength (ft0) of this hybrid was calculated and its value obtained was 60,8 MPa. The shear strength (fv0) was 8,2 MPa. The results obtained from the tests are the basis for engineers and architects to design structures using wood species Amaru

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Any failure process that may occur in a part probably is located where the stress exceeded the level of resistance. When a part or component has a sharp change in geometry, such as slots, holes, grooves, bumps or other irregularities, there is an increased concentration of stress at a specific location of the part. The objective of this study is to determine the maximum stresses in structural parts and components using the equations of elasticity theory in conjunction with the stress concentration factor experiment and compare them with results obtained by finite element method

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Com base nas coletas realizadas em quatro parcelas de um hectare (Designadas pelas letras B, C, D e E localizadas no Núcleo Picinguaba, município de Ubatuba, São Paulo, foi levantada uma base de dados florísticos e fitossociológicos para a família Myrtaceae. Todas as parcelas situam-se em área de ocorrência de Floresta Ombrófila Densa e estão inseridas no Projeto Temático “Composição florística, estrutura e funcionamento da Floresta Ombrófila Densa dos Núcleos Picinguaba e Santa Virgínia do Parque Estadual da Serra do Mar” do Programa BIOTA-FAPESP. O estudo teve como objetivo investigar a influência de Myrtaceae na constituição estrutural e diversidade do componente arbóreo no trecho florestal amostrado. No total foram amostradas 66 espécies para a família, distribuídas em 9 gêneros, sendo que Eugenia foi o gênero de maior riqueza. A parcela B foi a que mais apresentou espécies de Myrtaceae. Dos 4750 indivíduos contemplados, Myrtaceae contribuiu com 861, sendo precedida apenas por Rubiaceae com 922 indivíduos; A parcela E concentrou o maior número deles (223); Da área basal total 106,17 m², Myrtaceae contribui com 16,16 m². Apareceu com frequência absoluta entre 85% e 90% nas quatro parcelas, totalizando 87,5% nos 4 ha. Apresentou diâmetro e altura média de 12,73 cm e 8,17m respectivamente. Foi a família mais importante em todas parcelas (VI), apresentando valor de importância de 15,24% quando calculado para a somatória das quatro parcelas. O índice de Shannon calculado para parcela B, C, D, E e total foi 4,12 nats/ind; 3,98 nats/ind; 4,00 nats/ind; 4,06 nats/ind; 4,23 nats/ind respectivamente. A equabilidade foi 0,82; 082; 0,79; 0,82; 0,76 respectivamente. Para as espécies de Myrtaceae, Marlierea obscura destacou-se em primeiro lugar quanto ao número de indivíduos (83), frequência absoluta (18,5%), dominância absoluta (0,46), sendo assim... (Resumo completo, clicar acesso eletrônico abaixo)

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The study area is includes in the geological context of Arenópolis Magmatic Arc, a region where there are neoproterozoic associations of granodioritic and tonalitic composiotion. (Ortogneisses of the western Goiás) and sequences metavolcanic-sedimentary (Jaupaci Metavolcanic-sedimentary Sequence ). In the mapped area, both units are covered by a cover-laterite. The Ortogneisses from Goiás West consist of a source granodioritic gneisses, corresponding to the Biotite granodiorite gneisse, and also by tonalitic gneiss composition corresponding to Metatonalit. The Jaupaci Metavolcanic-sedimentary Sequence is formed by Chlorite Schist (Metabasalt), Biotite Schist (Metadacite) and Sericite Schist (Metarhyolite), and even intrusions Sin/Tardi e Post Tectonic, granite to diorite composition (Diorites), and alson tonalitic (Bacilandia Tonalite). Post tectonic intrusions are observed, wich were Hornblend Diorite Porphyry and Lamprophyres, Structural analysis allowed the identification of three deformational events, Dn-1, Dn and Post-Dn. The first event is associated with a bygone foliation, lineation which generates an intersectional event, generating the foliation Sn, this being the most important structure in the study area, generating even the type mineral lineation and stretch. The last deformational event is characterized by folds on different scales, affecting the Sn foliation. The rocks of the region have features s active hydrothermal and regional metamorphism, and are composed os assembly indicative of mineralogical facies metamorphism Green Schist, in chlotite zone, with evidence of retro metamorphism. Locally there are sulfides as pyrite, arsenopyrit and pyrhotite, and te mineralization is associated with the arsenopyrite

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The automobile industry is increasingly interested in reducing vehicle weight for greater speed, lower fuel consumption and emissions, through innovation of materials and processes. One way to do this is to seek the replacement of conventional processes by the use of structural adhesives. Structural adhesives are highly resistant materials, which can replace rivets, bolts and welds allowing the substrate / adhesive assemble is stronger than the substrate itself. One of the major advantages of gluing with respect to welding is its esthetic appearance, since it does not leave marks. For this reason, parts to be soldered require a minimum thickness so that the marks do not appear, since the pieces from gluing have no restriction as to the thickness. By replacing the vibration welding process for gluing process of the instrument panel parts of an automobile, one obtains a reduction of the thickness of the parts and therefore it decreases the weight of the car. This work aims to study the various structural adhesives that already exist on the market to be applied on the instrument panel. The mechanical test performed to measure the maximum adhesive strength was the Lap Shear Test at 23°C (room temperature), -35°C and 85°C. The types of adhesives used were the hot-melt and the bi-component. By the results obtained, it is in favor using the bi-component for application to the union of instrument panel parts

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The need for development of new materials is a natural process in the companies’ technological point of view, seeking improvements in materials and processes. Specifically, among the materials, ceramic exhibit valuable properties, especially the covalent ceramics which have excellent properties for applications which requires the abrasion resistance, hardness, high temperatures, resistence, etc. being a material that has applications in several areas. Most studies are related to improvement of properties, specially fracture toughness that allows the expansion of its application. Among the most promising ceramic materials are silicon nitride (Si3N4) which has excellent properties. The goal of this work was the development and caracterization of Si3N4-based ceramics, doped with yttrium oxide (Y2O3), rar earth concentrate (CTR2O3) and cerium oxide (CeO2) in the same proportion for the evaluation of properties. The powders' mixtures were homogenized, dried and compressed under pressure uniaxial and isostatic. Sintering was carried out in 1850 ⁰C under pressure of 0,1MPa N2 for 1 h with a heating rate of 25 ⁰C / min and cooling in the furnace inertia. The characterizations were performed using Archimedes principle to relative density, weight loss by measuring before and after sintering, phase analysis by X-ray diffraction, microstructure by scanning electron microscope (SEM), hardness and fracture toughness by the method Vickers indentation. The results obtained showed relative density of 97-98%, Vickers hardness 17 to 19 GPa, fracture toughness 5.6 to 6.8 MPa.m1/2, with phases varying from α-SiAlON and β-Si3N4 depending the types of additives used. The results are promising for tribological applications and can be defined according to the types of additives to be used

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

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O uso contínuo de antifúngicos tópicos e sistêmicos no tratamento convencional de candidose oral tem resultado no aparecimento de Candida albicans resistente. Por este motivo, novas tecnologias para o desenvolvimento de drogas, como os biofármacos, constituem uma estratégia, além de inovadora devido a seu mecanismo de ação, também promissora no campo da biotecnologia. Verificou-se que esta nova tecnologia possui potencial efeito em diminuir a resistência de microrganismos, especialmente do agente etiológico da candidose bucal. A Candida albicans, agente patológico de origem fúngica, expressa diversos fatores de virulência sendo comumente encontrada na pele, cavidade oral, esôfago, trato gastrointestinal e órgão reprodutor feminino podendo acometer pessoas de idades variadas, imunologicamente comprometidas, ou que utilizam próteses dentárias. Nesse sentido, peptídeos com efeito antifúngico, produzidos por plantas, animais e microrganismos estão sendo utilizados como modelos para o desenvolvimento de novas drogas com aplicações em saúde. A Histatina 5 é um peptídeo encontrado na saliva humana com forte propriedade fungicida in vitro. Este peptídeo é extremamente rico nos aminoácidos histidina e lisina e, em pH fisiológico, possui potencial de inibição da formação do biofilme de Candida albicans, podendo ser aplicado portanto, no tratamento da candidose oral. Nesse contexto, o presente estudo consiste na obtenção de análogos da Histatina-5 com modificações em sua estrutura molecular, com o objetivo de otimizar o seu potencial terapêutico já verificado nos peptídeos da família das Histatinas. A Histatina 5SC possui o aminoácido serina C-terminal substituído pela cisteína, o qual é constituído pelo grupo sulfidrila em sua cadeia lateral, para a formação de dímeros. Os peptídeos foram desenvolvidos sinteticamente pelo método de Síntese Orgânica em Fase Sólida, utilizando-se a estratégia Fmoc e...

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In the early 1990 Gary Gereffi and Miguel Korzeniewicz published the book Commodity Chains and Global Capitalism. In the two decades prior to the publication, industrialization worldwide, had undergone significant changes, made more segmented and dispersed in certain regions. In the book, the authors produce a new set of categories to analyze the new standards for establishment and operation of global value chains, their organization, the new geography of manufacturing and the role of the countries in this scenario. Today, in the middle of the second decade of this century, world trade has expanded and multiplied continuously throughout this period, encouraged by reducing barriers and national borders promoted by 'peddlers' of this new era. The purpose of this study is to show that retailers are establishing purchasing offices in producing countries - or in nearby regions - to directly hire outsourced production

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Pós-graduação em Engenharia Mecânica - FEIS

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA