239 resultados para Ensaios mecânicos


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To perform the quality control of various industries like: petrochemical, nuclear, aerospace, steel, shipbuilding, pulp and paper, and inspection of welded products, castings, forgings, rolled products, among others, used the method of Non-Destructive Testing (NDT). The method is based on the physical properties of the material, so selecting a procedure more appropriate. The company Inter-Metro Serviços Especiais Ltda., with its cutting-edge laboratory, dedicated to the implementation of calibration services and measurement equipment for industrial, medical, occupational safety and Non-Destructive Testing (NDT). It has a trained team, providing guidance and providing support for improving procedures for testing and measuring

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A presença de falhas, trincas, furos e fadigas causam perturbações nos modos vibracionais (normais) de uma estrutura, por exemplo, tubos, gasodutos e peças metálicas. Uma vez conhecido o espectro de freqüência de uma estrutura instalada em condições normais (sem falhas), é possível acompanhar através, de ensaios não destrutivos uma alteração no espectro de freqüência que pode estar associado a alguma falha mecânica na estrutura.O presente trabalho busca encontrar um padrão nos sinais de resposta dos materiais analisados pela técnica de Vibroacustografia, antes e depois das deformidades causadas. Tentando viabilizar a técnica para a utilização em Ensaios Não Destrutivos (END). E futuramente, para as amostras biológicas, espera-se estender os conhecimentos obtidos dos ensaios anteriores para detecção e prevenção de possíveis fraturas do tecido ósseo

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With growing electricty demand, the importance of generation through hydropower, a renewable energy source, it’s of great importance. This demand derives from the country’s growth, as well as events that will occur in the coming years. The commission has a crucial role before the entry into operation of hydroelectric plant, sice, ensures a good operation of hydraulic and electrical systems, as well as the safety of the installation. This paper is a case study, commissioning in a PCH in especially the most important tests, such as range operation, índex tes and load rejection. In these trials we can get a Idea of the actual behavior of the unit, as well as future operation maneuvers, and evidence of real efficiency

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This work is the production of two types of particle boards reconstructed MDP (Medium Density Particleboard), the first with the addition, in the inner layer of particles of impregnated paper, the ratios of 0%, 1%, 5% and 20 %. In the second type of panel MDP was inserted with blades of bamboo species Dendrocalumus giganteus as coatings and structural reinforcement. The MDP panel, used as a basis for both cases has the composition of three layers, two external particles with smaller particle size and an inner layer composed of particles of larger particle sizes. Assays were performed based on physical and mechanical NBR 14.810/2006 for the determination of the board density, thickness swelling, water absorption, moisture content, bending, tension parallel and perpendicular, and testing of particle sizes of the particles did not exists in standard references. The results were analyzed and compared the results of the commercial boards made from 100% eucalyptus, based on the limits specified by the ABNT NBR 14.810/2006. The values of the tests showed similar results indicating normative specifications in a positive way, the possibility of production of MDP with the use of waste paper impregnated. As for the panel with bamboo blades, the tests showed a mechanical performance far superior to MDP market, explaining the study and possible implementation of the bamboo for use where the MDP will suffer greater mechanical stress, such as doors, tops and benches tables

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Nowadays technological trend is based on finding materials that could support low weight with satisfactory mechanical properties and for this reason composite material became a very attractive topic in research projects all over the world. Due to its heterogenic properties, this type of material shows scatter in mechanical test results, especially in cyclic loading. Therefore it is important to predict its fatigue strength behaviour by statistic analysis, once fatigue causes approximately 90% of the failure in structural components. The present work aimed to investigate the fatigue behaviour of the Twill/Cycom 890 composite, which is carbon fiber reinforced with polymeric resin as matrix and manufactured via RTM process (Resin Transfer Molding). All samples were tested in different tensile level in triplicate in order to associate these values. The statistical analysis was conducted with Two-Parameter Weibull Distribution and then evaluated the fatigue life results for the composite. Weibull graphics were used to determine the scale and shape parameters. The S-N curve for the Twill/Cycom composite was drawn and indicated the number of cycles to occur the first damages in this material. The probability of failure was associated with material reliability, as shown in graphics for the different tensile levels and fatigue life. In addition, the laminate was evaluated by ultrasonic inspection showing a regular impregnation. The fractographic analysis conducted by SEM showed failure mechanisms for polymeric composites associated to cyclic loadings ... (Complete abstract click electronic access below)

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There are many approaches and techniques about Administration and Management of Projects in order to provide greater agility, efficiency and transparency during the development process of new products. Simultaneously, a pursuit for a management approach more flexible in its planning and strategic changes during the development campaign, such as, comprehend the project's unpredictability level and deal it by monitoring and estimates tools. These features tend to accentuate itself in manufacturers of complex products, as aircraft and other aerospace technologies. By these conditions thus research aims to describe a case when the Agile Management Processing of Project Development Scrum was used in the Test area of an aircraft manufacturer. Focused on the Scrum implementation over the area, its adaptation, evolution and achievements the research proposes to analyze the improvements, indicate the obstacles and discuss solutions, contributing then to the theoretical basis of the considered theme and futures updates applicable to the area. The research is classified as qualitative; furthermore the information and data analyzed were obtained by interviews with professionals and observations of the processes from the major aircraft manufacturer

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The growth of urban population associated with the shortage of supply of public infrastructure such as hospitals, kindergartens, schools, among others, has reinforced the need to develop alternative methods that simplify the construction processes and allows for a reduction in these costs works. The conventional processes have increasingly been shown ineffective to solve the problem of demand for different types of urban and rural buildings. Given this fact, industrial construction processes can gain space and have proven to be highly interesting to solve the above problems, in particular, considering the cost-effective and time. Therefore, this study aimed to determine the influence of moisture on the strength of metal plate connections connectors (printed plate with teeth). For the sizing of the links between structural lumber using metal connectors with teeth prints; controlled process variables (drying of the wood and the different moisture contents), and finally found results and compare them with different literatures order to obtain a qualitative efficiency of the process. Some specimens had very low expectations, can be explained by the presence of bone marrow, and pre-existing cracks. Thus, the results were discarded for further analysis and more accurate results

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A psoríase é uma doença inflamatória relativamente comum da pele e das articulações, podendo se tornar crônica. Nos últimos anos, a expansão do arsenal terapêutico para o paciente com psoríase tem permitido aos médicos combaterem, de forma mais agressiva, a patogênese da doença. Um fármaco utilizado para o tratamento é o metotrexato, que, apesar de ser bastante eficaz, possui potencial para a toxicidade sistêmica, como toxicidade hematológica, hepática e pulmonar. Sendo assim, muita atenção tem sido dada ao desenvolvimento de novos veículos com o objetivo não só de aumentar a eficácia terapêutica de substâncias ativas, como também de permitir a redução da sua dose total necessária, minimizando os efeitos colaterais tóxicos. Os cristais-líquidos são sistemas promissores para aplicação tópica, pois promovem liberação controlada de fármacos, contribuindo para amenizar efeitos adversos, por exemplo, do metotrexato. Uma vez que há possibilidade de as substâncias incorporadas em formulações tópicas serem absorvidas pela pele e mucosas, existe a necessidade de garantir que as formulações sejam seguras. Este trabalho teve o objetivo de avaliar a bioadesão e a citotoxicidade in vitro de três sistemas líquido-cristalinos contendo metotrexato para o tratamento da psoríase. Resultados de bioadesão revelaram que as três formulações analisadas apresentaram forças bioadesivas próximas, sendo o sistema A mais bioadesivo. Com relação a estudos de reologia, houve comportamento de fluido não-newtoniano, pseudoplástico e tixotrópico. Além disso, a adição de metotrexato à formulação A, aumentou a viscosidade do sistema. Ensaios de citotoxicidade sugerem a possibilidade de liberação prolongada de metotrexato, contribuindo para o aumento da viabilidade celular

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This study is about a heating line that uses thermal oil. It is located in a facility that produces interlayers used in cars windshields. A plastic resin is melted and is sent to a matrix called DIE where the interlayers are produced. The DIE needs to receive heat from the circulation of thermal oil in four different regions of its interior, to ensure the correct thickness of the interlayer. The thermal energy is provided by electric heaters and the flow of thermal oil is impelled by four mechanically sealed centrifugal pumps (one per region). The key point of this study is the fact that these four pumps of the system have reported successive failures in the mechanical seals. Apparently, a poorly designed project has burdened the system intermittently. The pumps operation condition is located in a region of low efficiency, according to the characteristic curves. This fact is the source of the noticeable reduced time between failures. Changes in the configuration of the facility and in the number of pumps will be proposed, aiming to achieve higher operational efficiency. The proposals will be mathematically analyzed according to the Hydraulic Institute criteria. At the same time, we will also keep focus on an in-depth study of a heating system structure, starting with a detailed approach for each component and discussion about its real need and economic viability. At the end of this paper it is shown that the gain in efficiency achieved with the new proposed configuration reflects not only in the reduction of maintenance costs, but also a potential improvement in energy efficiency. It is shown that these two aspects are closely related and together form the basis for the design of a reliable and efficient pumping system

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Coleus blumei Benth (Lamiaceae), popularly known in Brazil as heart-hurt or coleus-of-Java is an ornamental plant widely used due to the color of its leaves. Several species of the genus Coleus present compounds with antioxidant, antimicrobial and allopathic activities due to the presence of chemicals such coleonol, forskolin and rosmarinic acid. Therefore, this study aimed to carry out phytochemical study and biological tests to evaluate the antibacterial, antioxidant and allopathic activities of the 70% ethanol extract and its fractions ethyl acetate, dichloromethane and end aqueous fraction leaf of Coleus blumei Benth. The plant extract was prepared by turbolisis from the powder of dried leaves, as a solvent for extraction using 70% ethanol. The ethanol extract was fractionated with solvents dichloromethane and ethyl acetate. The phytochemical study identified the presence of saponins, free anthraquinones, flavonoids and anthocyanidins. In evaluating the antibacterial dichloromethane fraction showed activity against all microorganisms tested both in agar diffusion test and microdilution test. The 70% ethanol extract showed activity against the micro-organisms S. aureus and S. epidermidis in agar diffusion test and against all microorganisms tested in microdilution test. The ethyl acetate fraction showed activity against the micro-organism S. aureus in the agar diffusion test and against all microorganisms tested in microdilution test. The end aqueous fraction showed no activity against any micro-organism tested. In the test of evaluation activity allopathic dichloromethane fraction showed greater inhibition of seed germination and growth of tomato (Lycopersicon esculentum Mill), followed by 70% ethanolic extract, the ethyl acetate fraction and the end aqueous fraction. In testing the antioxidant activity with DPPH ethyl acetate fraction showed higher antioxidant activity followed... (Complete abstract click electronic access below)

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Hybrid composites combining metal plates and laminates with continuous fiber reinforced polymer, called fiber-metal (CHMF), have been particularly attractive for aerospace applications, due mainly to their high mechanical strength and stiffness associated with low density. These laminates (CHMF) consist of a sandwich structure consisting of layers of polymer composites and metal plates, stacked alternately. This setting allows you to combine the best mechanical performance of polymer composites reinforced with long fibers, to the high toughness of metals. Environmental effects should always be considered in the design of structural components, because these materials in applications are submitted to the effects of moisture in the atmosphere, the large cyclical variations of temperature around 82 ° C to -56 ° C, and high effort mechanical. The specimens of fibermetal composite were prepared at EMBRAER with titanium plates and laminates of carbon fiber/epoxy resin. This study aims to evaluate the effect of different environmental conditions (water immersion, hygrothermal chamber and thermal shock) of laminate hybrid titanium/carbon fiber/epoxy resin. The effects of conditioning were evaluated by interlaminar shear tests - ILSS, tensile, and vibration free

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Bamboo has one of the highest growth rates among plants, however, its lignifications (which confers resistance) takes around a few years and, therefore, certain physical characteristics and mechanical, that depend on this process will only be acquired between the three to six years old. In addition, bamboo also has significant density variations in different parts of the stem, both in the radial direction as the axial. In particular the radial direction, where the density found in the inner and outer (near the bark) of a single stem can range on average from 0.5 to 0.9 g/cm3. Thus, the application of bamboo as a floor, there to examine whether both sides of the bamboo (internal and external), provide resistance properties required for that purpose. In this study sought to characterize and quantify the influence of the concentration of fiber bundles in the inner and outer sides of rules or bamboo strips of bamboo flooring through testing service. Analyses performed were based on ASTM D 2394- 83 for wooden floors and derivatives. This was necessary because of the absence of a specific prohibition of the use and testing of floors made of bamboo and its products. The data were analyzed by ball indentation test shooting, test for resistance to abrasion, indentation test for stress / load treadmill test and by indentation loads applied to small areas - test the jump. The results of the tests were extremely friendly bamboo, even this presents considerable differences between the resistances obtained from assay of the cover of the inner and outer face, being comparable with those of many commonly used to manufacture wood flooring. This comparison was made possible by information from technical trials of several floors made with wood

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O Brasil é um país dotado de Biodiversidade incomparável da qual advém inúmeras plantas medicinais que são frequentemente utilizadas de acordo com conhecimento empírico da população em geral. Considerando a importância de investigar os efeitos farmacológicos e toxicológicos de espécies vegetais utilizadas com fins terapêuticos, foi objetivo do presente trabalho avaliar a atividade mutagênica dos extratos metanólicos e hexânicos de Pouteria ramiflora e Pouteria torta, pois seus dados farmacológicos descritos na literatura são bastante restritos, destacando-se as atividades antimicrobiana, citotóxica e imunomoduladora. Como ferramenta foram escolhidos os testes de Ames e do Micronúcleo, pois ambos são preconizados pela ANVISA em testes de toxicidade de fitoterápicos. No Teste de Ames foram utilizadas as linhagens TA100, TA98, TA97a e TA102 de Salmonella typhimurium em presença e ausência de metabolização e no ensaio do micronúcleo foi utilizado o sangue periférico de camundongos Swiss tratados in vivo. Os resultados constataram que os extratos de ambas as espécies provocaram desvios da normalidade, ou seja, o Teste de Ames detectou aumento no número de revertentes por placa e o Teste do micronúcleo mostrou aumento significativo no número de células micronucleadas. Esses resultados demonstraram claramente que as duas espécies de Pouteria estudadas apresentaram potencial mutagênico e, portanto, o uso popular dessas plantas deve ser feito com cautela

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O presente trabalho teve como objetivo estudar a biodegradação de efluente oleosos em ambiente terrestre. Foram avaliados os potenciais degradação dos seguintes óleos: óleo lubrificante automotivo usado, óleo vegetal novo e usado, e biodiesel. Os ensaios realizados objetivaram, pelo método de respirometria, quantificar e comparar as porcentagens de biodegradação medida através da formação do CO2 da respirometria bacteriana entre amostras de solos contaminados por diferentes tipos de óleo. Além destes ensaios, foram realizados testes colorimétricos que, indicarão, pela mudança de cor do indicador, quais os óleos levam mais tempo para serem completamente degradados. Dessa maneira, foi possível verificar a degradabilidade relativa dos óleos, e contribuir para futuras pesquisas envolvendo a poluição de ambientes com efluentes oleosos. Os dados coletados permitiram verificar a toxicidade e biodegradabilidade relativa dos óleos, de modo que os ensaios contendo biodiesel e óleo vegetal novo tiveram menor índice de biodegradação, quando comparado ao óleo automotivo usado.