Orientadores: Ana Elisabete Paganelli Guimarães de Avila Jacintho, João Alberto Venegas Requena / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T12:43:40Z (GMT). No. of bitstreams: 1 Simoes_Renato_M.pdf: 4003726 bytes, checksum: d64741e911e9a1baef5581cc04dec747 (MD5) Previous issue date: 2008 / Resumo: O emprego das estruturas mistas está cada vez mais comum, pois as mesmas apresentam vantagens construtivas em relação às estruturas convencionais de aço ou concreto. Este sistema construtivo, ainda é novidade em muitos países, porém Japão e Estados Unidos da América que já fazem uso, atualmente estão desenvolvendo novas pesquisas para o aperfeiçoamento das técnicas de projeto e construção de tal sistema. Esta pesquisa visa estudar o efeito do confinamento presente nos pilares mistos tubulares circulares preenchidos com concreto verificando, assim, como e quanto há de interação entre o tubo metálico e o concreto de preenchimento sob o efeito de força axial de compressão comparando-os assim com os métodos de dimensionamento propostos pelas normas. O projeto de revisão da NBR 8800:2003 e o Eurocode 4:1994, na consideração do efeito do confinamento apresentam um dimensionamento inseguro, entretanto a especificação americana AISC ASD:1999, que não considera o confinamento apresenta resultados mais próximos daqueles encontrados nesta pesquisa. Nas comparações dos resultados experimentais com os resultados propostos pelas normas é notável a grande importância de uma consideração mais detalhada no dimensionamento da relação diâmetro / espessura das seções mistas. Nesta pesquisa o comportamento das seções mistas foi diferente para cada relação diâmetro / espessura proposta / Abstract: Not informed. / Mestrado / Estruturas / Mestre em Engenharia Civil

A utilização do aço ASTM A 335 P91 tem sofrido um aumento considerável, especialmente em função da necessidade de materiais com maior resistência à fluência para aplicações em unidades de utilidades (geração de vapor) e de processo. Por ser um material de difícil soldabilidade, diversos problemas são enfrentados durante a construção das unidades e, posteriormente, durante manutenção, geralmente em função de problemas de soldagem oriundos da fase de fabricação e construção. As normas de projeto e construção utilizadas internacionalmente vêm sofrendo adaptações a fim de melhorar a utilização deste material, mas seus requisitos ainda apresentam importantes lacunas em relação às principais práticas recomendadas pela literatura técnica mais atual. Visando uma melhor utilização deste material, obtendo juntas soldadas com propriedades mecânicas e metalúrgicas mais consistentes, o presente trabalho foi desenvolvido avaliando-se a influência de parâmetros de soldagem energia de soldagem e temperatura de tratamento térmico pós-soldagem (TTPS) sobre as propriedades mecânicas e metalúrgicas, incluindo resistência à fluência, de juntas soldadas de aço ASTM A 335 P91. Foram testadas nove juntas soldadas, combinando três níveis de energia de soldagem com três temperaturas de TTPS. Os resultados obtidos indicam que é possível ter melhor controle sobre as propriedades deste material, desde que se opere com níveis mais restritos de energia de soldagem e maiores temperatura de TTPS, observando-se as limitações pertinentes, especialmente no que tange à temperatura crítica de transformação Ac1. / The use of ASTM A 335 P91 has been increased considerably specially because of the need for materials with higher creep resistance for power generation (nuclear and thermoelectric) and oil and gas processing applications. As this is a material with poor weldability, several issues are faced during construction of these unities, and later during maintenance usually associated with welding problems originated in the fabrication and construction phase. The design and construction codes most used worldwide are receiving important revisions targeting to enhance the use condition of this material but its requirements still show important lacks when compared to the main practices recommended by the more recent technical literature. Aiming a better usage of this material obtaining sound welded joints with more consistent metallurgical and mechanical properties, this work was developed assessing the influence of some welding parameters welding heat input and temperature of post-­weld heat treatment (PWHT) on the metallurgical and mechanical properties, including creep strength, of welded joints of ASTM A 335 P91 steel. Nine welded joints were submitted to testing, combining three different levels of welding heat input with three different PWHT temperatures. The results show that it is possible to have a better control over the properties of this material since it is used lower welding heat inputs combined to higher PWHT temperatures, taking care about the limitations regarding the critical transformation temperature Ac1.

Orientador: João Alberto Venegas Requena / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-03T17:23:22Z (GMT). No. of bitstreams: 1 Minchillo_DanielaGrintaciVasconcellos_M.pdf: 4304194 bytes, checksum: 578d9bc4e3992a6df227aa6eb834c0db (MD5) Previous issue date: 2003 / Resumo: Neste trabalho, são apresentadas análises de ligações metálicas tubulares de placas de bases para pilares de perfis de seção circular através de modelagem pelo método dos elementos finitos. O Método dos Elementos Finitos é uma técnica que permite uma modelagem eficaz para a simulação do comportamento real das ligações em estudo. Para esta análise, foi utilizado o programa computacional ANSYS. Foram analisadas diferentes situações de carregamento na conexão pilar-placa de base, bem como vários tipos de enrijecedores e as respectivas distribuições de tensões obtidas para cada caso. O estudo foi desenvolvido de forma comparativa entre a modelagem computacional e as expressões analíticas encontradas em normas internacionais, destacando: AISC-Hollow Structural Sections (Connections Manual), AISC-LRFD (1996)-(Load and Resistance Factor Design) e o EUROCODE3 (1992). São apresentados exemplos numéricos, evidenciando as diferenças encontradas no estudo / Abstract: In this work finite element analysis of steel column base plate conections joining circular hollow sections are presented. The finite element method is a technique that allows investigating the real behavior of the studied connection. For this analysis, the computer program ANSYS was used. Different load situations had been analyzed in the base-plate connection, as well as various types of stiffeners and the respective distributions of tensions for each case. Different load situations had been analyzed in the base-plate connection, as well as various types of stiffeners and the respective distributions of tensions for each case. The study was developed in a comparative way between the computer modeling and the analytic expressions found in international codes, highlighting: AISC-Hollow Structural Sections (Connections Manual), AISC-LRFD (Load and Resistance Factor Design) and Eurocode3. Numeric examples are presented and compared to evidence the differences among the codes and procedures used in this study / Mestrado / Estruturas / Mestre em Engenharia Civil

[pt] O presente estudo faz parte de um projeto relacionado ao estudo de aplicação de tubos de aço API 5L Grau X80 fabricados no Brasil e destinados para a montagem de tubulações para o transporte de gás. Objetiva-se avaliar os parâmetros de soldagem empregados na execução da soldagem circunferencial combinando os processos de eletrodo revestido, para a execução do passe de raiz e passe quente, e arame tubular autoprotegido para a execução dos passes de enchimento e acabamento. Os resultados obtidos indicam que embora o material utilizado, tanto metal de solda como metal de base estejam atendendo aos requisitos básicos de tenacidade e resistência, em acordo com as normas, a qualificação do procedimento é dependente do desempenho dos soldadores. Existe portanto, a necessidade de habilitação técnica mais ampla quanto a formação de profissionais nesta área, excedendo assim o escopo do presente estudo cujo objetivo foi estudar e caracterizar a solda circunferencial. As propriedades mecânicas foram avaliadas mediante ensaios de dureza, tração, dobramento, ensaios nick-break e tenacidade mediante ensaios de impacto Charpy. A caracterização da junta soldada foi realizada, utilizando-se microscopia ótica e microscopia eletrônica de varredura. Embora o procedimento empregado não tenha sido qualificado pela norma API 1104, em função da execução do procedimento, os valores de resistência mecânica obtidos foram aceitáveis e a caracterização microestrutural e mecânica da junta comprova a não ocorrência de microestruturas frágeis, seja no metal de solda ou na ZTA. / [en] The current work is part of a larger project to study the application of API 5L X80 steel tubes, produced in Brazil, in gas pipeline fabrication. The objective of this work is to evaluate the effects of the process parameters used when performing a circumferential welding technique which combines the utilization of coated electrodes for the root and hot passes, while exploiting self-shielded flux cored arc welding for the filling and finishing passes. The results obtained indicate that, though the material studied, both filler metal and the base alloy, meet the basic toughness and strength specifications of the relevant standards, the final overall quality of the joint is very dependent on the skill of the welders. Although there is a necessity to guarantee an adequate level of training for these professionals for such tasks, that would be beyond the scope of then present work, as it aims to emphasize the characterization of the circumferential weld itself. The mechanical properties were evaluated using hardness measurements, bend testing, nick-break tests and toughness was evaluated by Charpy notchimpact tests. The metallographic characterization of the girth weld joint was undertaken by means of optical and scanning electron microscopy. Though the specific methodology applied has not been qualified by the API 1104 Standard, as such, the strength values obtained were of acceptable levels and an analysis of the joint`s microstructure and overall mechanical properties confirm that no typical fragile structures or phases were present either in the weld metal or the heat affected zone.

En transplantation d’organe solide, les Inhibiteurs de la Calcineurine (ICN), Cyclosporine A et Tacrolimus, ont permis un amélioration significative de la survie à court terme du greffon en prévenant le rejet d’allogreffe. Cette évolution positive est contrebalancée par une néphrotoxicité susceptible de contribuer au développement complexe et multifactoriel de la dysfonction chronique du greffon, facteur pronostique majeur d’une insuffisance rénale terminale. L’objectif principal de ce travail a été de combiner deux approches expérimentales complémentaires, afin de mettre en lumière des aspects inédits de la physiopathologie des ICN. La première approche repose sur l’application de la technique de protéomique quantitative« shotgun » iTRAQ (« isobaric Tags for Relative & Absolute Quantitation ») à l’analyse non ciblée du protéome de cellules tubulaires proximales. La seconde approche applique de manière ciblée les outils classiques de biologie moléculaire à l’étude du cytosquelette d’Actine de cellules tubulaires proximales. La combinaison de ces deux stratégies complémentaires a permis de mettre en lumière un rôle inédit du cytosquelette d’Actine dans les effets physiopathologiques de la Cyclosporine A en apportant des éléments en faveur d’un mécanisme reposant sur une régulation originale de la dynamique intracellulaire de l’Actine. / In solid organ transplantation, Calcineurin Inhibitors, Cyclosporin A and Tacrolimus, prevent allograft rejection and ensure short-term allograft survival. However, CNI elicit nephrotoxic side effects whose mechanisms remain widely unsolved and are thought to participate to the multifactorial development of chronic kidney disease, leading to renal failure. The aim of thiswork was to combine targeted and untargeted experimental strategies to better understand CNI-induced physiopathological mechanisms.The first approach was based on the untargeted monitoring of the proximal tubular proteome by the quantitative shotgun proteomic technique, iTRAQ (« isobaric Tags for Relative & Absolute Quantitation »). The second approach consisted in the study of the Actin cytoskeleton of proximal tubular cells by classical molecular biology techniques. In the light of results from both approaches, this work reported that the Actin cytoskeleton of proximal tubular cells may play a part in the pathophysiology of CsA thanks to a mechanism based on an original regulation of the intracellular dynamics of Actin.

La myopathie à agrégats tubulaire (MTA) est une maladie rare caractérisée par la présence, dans la biopsie musculaire, d’« agrégats tubulaires ». Nous avons retrouvé 15 cas de MTA parmi 13987 biopsies musculaires réalisées dans les 35 dernières années dans notre service. Parmi ces cas, se trouvait une famille de trois patients qui ne pouvaient être inclus dans aucun groupe clinique connu de myopathie à agrégats tubulaires, car ils étaient asymptomatiques avec une hyperCKémie isolée et un test de contracture positif.Nos travaux ont mis en évidence des mutations hétérozygotes du gène STIM1. Ces mutations localisées dans la partie du gène qui code le domaine intraluminal EF-hand, entrainent une activation constitutive de STIM1 avec exacerbation du mécanisme SOCE et en conséquence l’augmentation de l’influx de Ca2+, démontré dans des myoblastes transfectés. Nous avons également mis en évidence la mutation p.Arg304Trp du gène STIM1, comme cause du syndrome de Stormorken. Cela augmente le spectre phénotypique des mutations de ce gène.Nos résultats de l’analyse protéomique montrent que la protéostase dans la MTA est dérégulée, car le profil du protéome est différent chez les patients et dans les agrégats tubulaires microdisséqués par laser, en comparaison a des contrôles. Les protéines enrichies s’avèrent appartenir à des voies biologiques impliquées dans l’homéostase ionique, les systèmes de membranes de la triade et de l’exosome et dans le métabolisme mitochondrial.Nos travaux ouvrent des perspectives pour mieux comprendre la physiopathologie de la myopathie à agrégats tubulaires et ainsi pouvoir proposer des solutions thérapeutiques efficaces. / Myopathy with tubular aggregates (MTA) is a rare disease characterized by the presence of tubular aggregates in muscle biopsy. We found 15 cases of MAT in our registry including 13987 muscle biopsies performed over 35 years. Among them, there was a family of three patients that did not fit any of the previously described clinical groups of MTA, since they were asymptomatic with isolated hyperCKemia and positive contracture test. Our works revealed heterozygous mutations in the gene STIM1. These mutations localized in the gene portion that codes for the intraluminal EF-hand domain, leads to a constitutive activation of STIM1 with SOCE mecanism enhancement and consequent increase of the Ca2+ entry which was demonstrated using transfected myoblasts. We also revealed the mutation p.Arg304Trp in the coding sequencing of the CC1 domain of STIM1, as the cause of Stormorken syndrome. This fact increases the phenotypical spectra of the mutations for this gene.The results of our proteomic analysis show that the proteostasis in MTA is disturbed, because the proteome profile is different in total muscle of the patients and in their tubular aggregates when compared to controls. The enriched proteins belong to the biological pathways linked to ionic homeostasis, membrane systems of the triads and the exosome, and to the mitochondrial metabolism.Our works bring perspectives for the continuation of our studies, in order to better understand the physiopathology of the myopathy with tubular aggregates and propose efficacious therapeutic solutions.

No description available.

This thesis deals with the design of the tubular frame for the Formula Student car competition. The first part is a brief introduction to the competition and used variants of frames. The main part starts with a list of restrictions by the rules and other necessary installation components. The central part is devoted to the draft modifications and their assessment in terms of torsional stiffness by FEM analysis. The final section presents the resulting frame design with respect to the required properties. The work is concluded final evaluation.

Cell migration is essential for homeostasis and the development of metastases. We hypothesize that cell migration is regulated by mitochondria and endoplasmic reticulum morphology. Using live cell microscopy, we found that mitochondria specifically migrate into the biochemically dense leading edge of the cell interacting with focal adhesions as well. At the leading edge the mitochondria are visibly shorter and less tubular than the perinuclear area. This is related to the elevated levels of fission events per minute in the leading edge and elevated levels of fusion events per minute in the trailing edge. We observe that mitochondria migrate along microtubules and simultaneously interact with the ER. When the ER is sheet-like the mitochondria are longer and tubular and when the ER is tubular the mitochondria are shorter and punctate. This change in ER and mitochondria morphology changes the cell’s ability to migrate. CLIMP63 cells have more sporadic turns, take longer to make turns, have shorter distances travelled and shorter displacements. To determine whether mitochondria dynamics play a role we examined these cell migration parameters in the presence of OPA1 and Drp1. This allowed us to conclude that the ER morphology is responsible for the distance and displacement the cell travels while the mitochondria is responsible for the angles the cell turns. When the ER is sheet-like the cells will be travel shorter total distances and displacements and when the cell has longer mitochondria it will be sporadic turns and take longer to make these turns.

>Magister Scientiae - MSc / Over the past 5 years, South Africa has been experiencing a severe drought. This has caused industrial and agricultural processes, to compete for a limited supply of water. Since the economy relies mostly on agricultural activities, water consumption by industrial processes is taking its toll. One of these processes is the introduction of wet flue gas desulphurization (FGD) treatment at Eskom coal fired power stations. This dissertation explores the possibility of using membrane technology as a means of water recovery after the coal combustion flue gas has been treated with wet FGD. A lab-scale permeance testing system was specially built and modified to have complete thermal control of the environment inside the system. The permeance testing system produced a gas, similar to that of a wet FGD treated flue gas, which was then tested. A tubular lab-scale membrane module was designed and produced for the permeance testing system. The permeance figures of both Nitrogen gas and water vapour were determined for the membrane used in module production. These figures coincided with figures provided by the supplier, which warranted successful permeance testing. After success of the lab-scale testing, the data was used to design and develop a pilot-scale membrane module. This module was designed to meet pre-determined requirements as set forth by the project team. Producing lab-scale membrane modules helped identify and address possible problems in pilot-scale module design. This lead to the successful design and construction of a pilot-scale membrane module that could be used to recover the water that is needed to run the wet FGD process.