Estudo da fragilização ao revenido em aço liga de 2,25CR-1MO através do ensaio de indentificação instrumentada

2,25Cr-1Mo alloy steels are widely used in petrochemical plant equipments working in high temperature conditions because of their good mechanical proprieties in these conditions. Although, when exposed for a long time at high temperature, in the rage of 343 °C to 593 °C, may present the temper embrittlement phenomenon. The component named stripper of assembly converter of fluid catalytic cracking unit (UFCC) of studied plant is manufactured using this material, which is subject to temper embrittlement. The phenomenon of temper embrittlement refers to progressive lose of toughness, making the material brittle. With embrittlement, equipaments manufactured with this material are under risks to suffer brittle fracture in the cool down and start-up situations of them, which can cause catastrophic failures. By this reason, this research studies presence of temper ebrittlement phenomenon on this material. To verify the toughness of the material is conventionally used charpy V-notch test. However, this test requires the removing of samples of the material to make specimens. This fact becomes critical when talk about structural components of an equipment. So, this research also studies a non-destructive test that can be executes in-situ, known as instrumented indentation, as an alternative detection of the phenomenon at the component stripper, by comparative of the mechanical proprieties obtained by conventional tests in similar samples

Influência de protetores físicos coloridos nas trocas gasosas de Canafístula (Peltophorum dubium (Spreng.) Taub.)

The aim of this experiment was to study the influence of transparent, blue and red tree shelters on gas exchanges of canafístula’s (Peltophorum dubium (Spreng.) Taub.) seedlings. This study was carried out in Department of Botany, Institute of Biosciences, U ESP, Botucatu, São Paulo State, Brazil. The experiment design was randomized blocks, with 5 replications, each one containing 6 units of each treatment (nonsheltered, transparent tree shelters, blue tree shelters and red tree shelters). The evaluations of gas exchanges were made through an infrared gas analyzer. It follows that the tree shelters use may limit the photosynthesis, increase the transpiration and stomatal opening, besides reducing the water use efficiency. The colored tree shelters use created unfavorable conditions for the development, reducing the photosynthesis, because they reflected the blue and red wavelengths, allowing only the passage of the other components of the white light or of the photosynthetically active radiation

Determinação experimental da tenacidade à fratura em baixas temperaturas de tubos de aço API 5L X70

Because of the great metallurgical advances, the welded tubes by HF / ERW (High Frequency / Electrical Resistance Welding) have played a more active role in the oil and gas, gradually replacing tubes produced by other processes (UOE, SAW, and others) to deep water applications, in high and extremely low temperatures, highpressure conditions and in highly corrosive environments. However, studies have revealed that defects in the welded joints are in one of main causes of failures in pipelines. Associated with damage external and the stringent requirements of this sector, the welded joints become particularly critical for his toughness and the determination of this particular property is fundamental. This study aims to evaluate the toughness of the HF / ERW pipes in HSLA steel API X70 class, used in pipelines transport systems of gas and oil from data obtained with CTOD tests (Crack Tip Opening Displacement). The main objectives of this project are: mechanical and microstructural characterization of steels API X70 manufactured in Brazil; and evaluation of the toughness of weld process by HF / ERW steel API X70 national. After having the tests done, mechanical, chemical and metallurgical, we have the conclusion that those pipe are in agreement to API 5L 42ª edition for X70MO and the toughness behaves like the expected

Busca de parceiros físicos das proteínas ADAM23 e MX1, utilizando o sistema de duplo híbrido em Saccharomyces cerevisae

A metilação de ilhas CpG em regiões regulatórias de vários genes tem sido descrita como um processo importante no silenciamento de genes supressores de tumor e diretamente envolvida no processo de carcinogênese de uma série de tumores. O estudo desses genes afetados pela metilação em tumores visa identificar possíveis marcadores moleculares para o diagnóstico, prognóstico e tratamento de tumores, além de possibilitar a descoberta de fatores importantes no processo biológico do câncer. Os genes MX1 e ADAM23 foram identificados como diferencialmente metilados em linhagens celulares provenientes de carcinoma de cabeça e pescoço. Neste sentido, ao estudar o perfil diferencial de metilação de genes em carcinomas de células escamosas de cabeça e pescoço, o gene MX1 foi identificado como diferencialmente expresso. Dessa forma, para elucidar a função destes genes no controle da carcinogênese, o presente estudo buscou identificar ligantes celulares das proteínas MX1 e ADAM23 por meio de rastreamentos de duplo-híbrido, usando bibliotecas de cDNA de cérebro fetal humano. Os rastreamentos com a proteína ADAM23 não geraram resultados positivos por isso não são aqui discutidos. Foi realizado rastreamento com a proteína MX1, que resultou em aproximadamente 1,0x106 transformantes, dos quais 74 foram confirmados pelo ensaio de duplo-híbrido e codificam para 9 ligantes já conhecidos e 21novos ligantes prováveis de MX1. Entre esses novos ligantes prováveis estão proteínas que já haviam sido descritas como ligantes de MX1, incluindo a própria proteína MX1, o que valida os resultados obtidos com este rastreamento. Além disso, grande parte dos ligantes identificados são fatores envolvidos no processo de SUMOilação de proteínas, na formação de corpúsculos nucleares denominados PML-NB e uma série de proteínas relacionadas ao controle da transcrição e apoptose... (Resumo completo, clicar acesso eletrônico abaixo)

Ensaios não destrutivos: metrologia e calibração

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

Diagnóstico ambiental no período frio e seco do Córrego Bandeirantes, município de Rio Claro, SP: parâmetros físicos, químicos e físico-químicos

The present study was concerned with checking the water quality, the recovery of the riparian vegetation and vegetation around the springhead of stream Bandeirantes, such as the inadequate disposal of waste along this stream, which is located in Rio Claro, SP, in the period from March to July of 2010. Aiming to propose mitigation measures to reverse the degradation processes and develop activities to help a better awareness of the population directly related to this water resource. The water quality was analyzed by performing monthly sampling in three different points along the stream. The first point of sampling is in the spring of the stream, the second at the region called estradão and the third near its mouth, when it flows into the Ribeirão Claro, a tributary of the right bank of the Corumbataí river. It was calculated from the Water Quality Index (WQI) developed by Cetesb. The results were compared with current law. The riparian vegetation, which is responsible for the protection of rivers and streams, was observed and examined during the field work. The results indicated the stream as class 2 and the WQI has been classified, in the most of the analysis, such as a water of good quality. However, some parameters showed a worrying situation and highlighted the current situation, with waste deposits, furniture and animal waste into the pit of the stream studied

Análise microestrutural de tubos API P110, para prospecção de petróleo e gás, soldados pelo processo HF/ERW

On the grounds of the great advances achieved over recent years, the process HF/ERW (High-Frequency/Electric Resistance Welding)welded pipe have played an active role in the oil and gas industry for deep water applications, at high and extremely low temperatures, under high pressure and in highly corrosive environments, gradually replacing manufactured pipes by other processes. However, studies have shown that defects in the welded joints are a the leading causes of pipelines failures, which has required the determination of toughness values in this region, in compliance with the strict recommendations of the codes and standards with manufacturers and construction companies, on the oil and gas sector. As part of the validation process required toughness values, this research project focuses on a microstructural analysis in HF / ERW tubes microalloyed, steel grade API 5CT P110, designed to explore oil and gas in deep waters, the subject of strategic relevance to the country because of the recent discoveries in the Santos mega fields: Tupi and Libra (pre-salt). In this scientific work will be presented and discussed the results of mechanical tensile and Charpy, a few CTOD tests curves (showing the trend of toughness values to be obtained), and the microstructures of the base material obtained by optical microscopy, with special emphasis on the formation of nonmetallic inclusions in the welded joint

Caracterização de compósitos produzidos por VARTM para aplicações aeronáuticas

In recent years the aeronautic industries has increased investment in areas of technological research aiming at materials that offer better performance, safety, weight reduction and fuel consumption. For this reason the most studied materials are polymeric materials, due to their higher mechanical strength and higher stiffness. This work evaluated characteristics of two composite laminates produced from the same process, but they differed only in regions where the resin was injected and the vacuum position. The composite laminates were SC-79 resin reinforced with glass fiber fabric (plain weave) processed via VARTM. For this reason the material was subjected to mechanical tests such as: tensile, and fatigue following standards ASTM D 3039 and ASTM D 3479, respectively. The latter was observed the S-N curve. It was performed the ultrassonic C-scan analysis to check impregnation of the fiber. Considering that the process was the same for the two laminates, with small variations in the injection and in vacum ports, it was expected to find similar characteristics

Análise das propriedades da madeira de estrutura de telhado após a ocorrência de um incêndio

The present study evaluated the mechanical properties of pieces of wood coming from the roof structure of a residence subject fire in the rural area of Itapeva/SP. The structure was built 25 years ago using wooden beams of the species Guarucaia (Peltophorum vogelianum), where the specimens were removed. The research methodology included qualitative evaluation of the samples, estimating the layer pyrolysis and carbonization of the wood, measuring of density and mechanical tests of compression parallel to grain, tension parallel to grain and shear. The mechanical properties of wood were analytically correlated with the layers carbonization and pyrolysis that are influenced by the temperature and time of fire; these values were estimated at 1000 °C and two hours for the case in question. The results indicate that the strength properties of degraded wood are different from a healthy wood. The level of thermodegradation, in general, can be measured by density, result in weight loss due to decomposition of the wooden components.

Estudo e aplicação da técnica de vibroacustografia em ensaios não destrutivos

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

Busca de parceiros físicos da proteína CRABP2, utilizando o sistema de duplo-híbrido em Saccharomyces cerevisae

A metilação de ilhas CpG em regiões regulatórias de vários genes tem sido descrita como um processo importante no silenciamento de genes supressores de tumor e diretamente envolvida no processo de carcinogênese de uma série de tumores. O estudo desses genes afetados pela metilação em tumores visa à procura de marcadores moleculares para o diagnóstico, prognóstico e tratamento de tumores, e também a caracterização do seu papel no processo biológico do câncer. O nosso grupo de pesquisa participou de um Projeto Temático que visa a identificação de genes metilados em tumores de cabeça e pescoço (processo 03/09497-3) e foi então proposta a utilização do sistema de duplo-híbrido de levedura como ferramenta no início da análise funcional destes genes. Dessa maneira, utilizando como isca o gene CRABP2 identificado como diferencialmente metilado em câncer de cabeça e pescoço, foi realizado o rastreamento de duplo-híbrido para a identificação de interações físicas proteína-proteína. Foram rastreados aproximadamente 2,1x105 transformantes neste sistema, dos quais 550 foram inicialmente positivos para His+. Desses, 182 transformantes confirmaram a marca His+ e foram testados para -galactosidase. Em seguida, 19 foram selecionados para passar pela etapa do “plasmid linkage”. Após esse teste, 9 clones confirmaram a ligação dos marcadores His+ e β-gal+ com a presença do plasmídeo LEU2 . Assim, após o sequenciamento dos insertos contidos nos clones identificados, ciclina D3 (CCND3), alfa-macroglobulina 2 (A2M) (2 clones), canal aniônico dependente de voltagem 2 (VDAC2), tubulina alfa 1 (TUBA1), tubulina alfa 2 (TUBA2), tubulina beta (TUBB), fator de ligação ao “enhancer” do gene interleucina 2 (ILF2) e desoxi-hipusina sintase (DHPS) emergiram como ligantes de CRABP2

Comissionamento de turbinas hidráulicas: ensaios de faixa operativa, índex, test e rejeição de carga

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

A organização dos espaços físicos das instituições regulares de ensino e suas contribuições no aprendizado das crianças portadoras de necessidades especiais

O presente trabalho tem como proposta discutir a respeito da organização dos espaços públicos destinados às pessoas portadoras de necessidades especiais. Procura analisar como a questão da acessibilidade vem sendo tratada, nas escolas e no meio urbano, além de identificar, no município de Rio Claro quais as adaptações/adequações foram realizadas recentemente, no sentido de garantir maior acessibilidade aos seus munícipes. O objetivo é o de analisar como se dá a adequação desses espaços e sua contribuição para a vida das pessoas. Constitui-se em pesquisa qualitativa de referencial bibliográfico pautada no levantamento de autores que problematizem a questão do espaço físico, e suas relações com a inclusão, a deficiência e a acessibilidade. Contando ainda com pesquisa de campo e registro fotográfico das adequações no Centro Comercial da cidade de Rio Claro

Estudo dos parâmetros físicos na fluidização em um leito gás sólido

Through measurements of basic parameters for determining the fluidization regime, as particle size, minimum fluidization velocity, bed porosity, etc., This paper analyze the mass distribution of the phases of the bed to be discussed in relation to: the flow gas physical properties of the solid particles and the forces acting on the solid particles circulating within the bed, as the weight force, buoyancy and drag forces (Stokes' Law). Due to the weight force is constant, open up the discussion about which of the other two forces, buoyancy and drag force, influencing the behavior of the bed. We used the photographic method to realize the statistical analyzes. Therefore, we can conclude what changes can be made more convenient in fluidizing the bed to obtain the highest efficiency for a good mixing used in industrial processes

Análise estatística da vida em fadiga de compósitos estruturais pela distribuição de Weibull

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)