Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O objetivo deste trabalho foi avaliar o efeito da tÃcnica de soldagem de aÃos AISI 8630M e ASTM A182 F22 aplicados em componentes estruturais subaquÃticos do setor PetrÃleo e GÃs Natural considerando os parÃmetros operacionais, suas caracterÃsticas metalÃrgicas e suas propriedades mecÃnicas. Foram fabricadas juntas dos aÃos AISI 8630M ou ASTM A182 F22 previamente amanteigados com a liga de nÃquel Inconel 625  ou com uma liga de aÃo baixo carbono comumente utilizada na soldagem do aÃo AISI 8630M. Foram utilizadas diferentes tÃcnicas de amanteigamento com e sem o uso de tratamentos tÃrmicos de alÃvio de tensÃes (TTAT). Para algumas das juntas amanteigadas sem TTAT foram depositadas camadas de amanteigamento de acordo com os parÃmetros sugeridos pelos testes de Higuchi e Higuchi modificado previamente realizados. Foram realizados ensaios de dureza, microdureza e de fratura para caracterizaÃÃo mecÃnica das interfaces de amanteigamento e, alÃm disso, foi realizada uma intensa caracterizaÃÃo microestrutural da mesma utilizando microscopia Ãtica, microscopia eletrÃnica de varredura e anÃlises de EDS e de EBSD. O teste de Higuchi mostrou-se uma boa opÃÃo para escolha dos parÃmetros de amanteigamento dos aÃos AISI 8630M e ASTM A182 F22. As juntas amanteigadas com condiÃÃes indicadas pelo teste de Higuchi apresentaram um intenso refino de grÃo na ZAC dos aÃos baixa liga, enquanto as juntas amanteigadas com condiÃÃes reprovadas apresentaram granulaÃÃo grosseira. A interface dissimilar apresentou composiÃÃo quÃmica intermediÃria entre os aÃos utilizados e a liga de nÃquel, sendo essa interface chamada de zona de alta diluiÃÃo (ZAD). As ZAD apresentaram pontos de microdureza elevada e, mesmo nas amostras submetidas a TTAT, nÃo foi possÃvel revenir essas regiÃes. A zona afetada pelo calor (ZAC) das amostras amanteigadas com parÃmetros indicados pelo teste de Higuchi e sem TTAT apresentou valores de dureza similares aos das amostras soldadas com parÃmetros reprovados no teste de Higuchi e com TTAT. Os ensaios de fratura indicaram que, de uma forma geral, o TTAT nÃo trouxe Ãs ZAC benefÃcios significativos relacionados à tenacidade dessas regiÃes e, alÃm disso, os mesmos podem comprometer a tenacidade da interface dissimilar. A anÃlise do caminho preferencial à propagaÃÃo das trincas indicou que o uso de TTAT tende a fragilizar a interface dissimilar, acredita-se que esse efeito està associado a difusÃo de carbono e possÃvel precipitaÃÃo de carbonetos durante esse tratamento. Acredita-se que essa possÃvel precipitaÃÃo pode ser ainda mais crÃtica quando à considerada uma fonte constante de hidrogÃnio para a junta (como em uma proteÃÃo catÃdica), essa hipÃtese traz à tona um questionamento a respeito da necessidade do uso de TTAT na fabricaÃÃo desse tipo de junta. / The aim of this study was to evaluate the effect of welding technique in the AISI 8630M and ASTM A182 F22 steels applied in offshore structural components for Oil and Natural Gas sectors. Joints of AISI 8630M or ASTM A182 F22 were fabricated and previously buttered with nickel alloy Inconel 625  or an alloy of low carbon steel commonly used in welding of AISI 8630M. Different techniques of buttering were performed with and without post welding heat treatment (PWHT). For some of the joints buttered without PWHT, buttering layers were deposited in accordance with the welding parameters suggested by Higuchi and modified Higuchi tests previously performed. Mechanical tests (hardness, microhardness and fracture) were accomplished for buttering interfaces and an intense microstructural characterization (optical microscopy, scanning electron microscopy, EDS and EBSD) was realized. Higuchi test has been showed as a good option to select parameters for AISI 8630M and ASTM A182 F22 buttering. The joints that were buttered using the conditions indicated by Higuchi test showed an intense grain refinement in the HAZ of low alloy steels, while the ones that was buttered with the conditions disapproved showed a coarse granulation. The dissimilar interface showed off intermediate chemical composition between the steel and nickel alloy, and this interface was called high dilution zone (HDZ). The HDZ revealed points of high hardness and, even in samples subjected to PWHT was not possible to anneal these regions. The heat affected zone (HAZ) of the samples buttered using the parameters indicated by Higuchi (without PWHT) showed hardness values similar to those of the samples welded with parameters that failed in the Higuchi test and with PWHT. In general, fracture tests showed that the PWHT not bring significant toughnessâs benefits to the HAZ, furthermore, may impair the toughness of dissimilar interface. The analysis of the preferred path for cracks propagation showed that the use of PWHT tends to weak the dissimilar interface, possibly this effect is related to carbon diffusion and possible carbide precipitation during this treatment. It is believed that this precipitation can be even more critical when considering a constant supply of hydrogen to the board (as in a cathodic protection), this reinforces the use of buttering techniques without subsequent heat treatment in the manufacture of this type of joints.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / A soldagem de revestimentos de ligas de nÃquel à utilizada pelas indÃstrias de petrÃleo e gÃs como opÃÃo de construÃÃo e reparo de estruturas e equipamentos submetidos em ambiente de condiÃÃes severas com o intuito de apresentar desempenhos necessÃrios de resistÃncia à corrosÃo. Muitos trabalhos foram desenvolvidos com superligas de nÃquel AWS ERNiCrMo-3, AWS ERNiCrMo-4 e AWS ERNiCr-Mo14, para avaliar resistÃncias à corrosÃo e a Ãltima se mostrou bem superior, porÃm o seu custo tambÃm à bem mais elevado que as outras duas. Assim, o trabalho vem aliar a alta produtividade do processo de soldagem MIG/MAG â DA atravÃs da soldagem de revestimentos com as ligas AWS ERNiCrMo-3 e AWS ERNiCrMo-4 na intenÃÃo de se obter uma mistura que apresente tanto a composiÃÃo quÃmica prÃxima a da liga AWS ER NiCr-Mo-14 como desempenho de resistÃncia a corrosÃo, porÃm com menor custo. Estudos exploratÃrios foram realizados por meio de soldagem com simples deposiÃÃo para determinaÃÃo da faixa de velocidade de soldagem entre 50 e 100 cm/min, modo de operaÃÃo da fonte em corrente constante pulsada e gÃs de proteÃÃo ArgÃnio puro. Os revestimentos foram soldados com menor energia (7,5 kJ/cm), tecimento triangular, eletrodos posicionados um atrÃs do outro em relaÃÃo a velocidade de soldagem e sem defasagem entre as correntes. Nessa etapa variou-se Ãngulo de ataque e o percentual de sobreposiÃÃo dos cordÃes. A melhor condiÃÃo apresentada foi menor diluiÃÃo, 9,75%, e elevado reforÃo, 3,92 mm, sendo essa obtida utilizando-se a tocha inclinada de 15Â, e sobreposiÃÃes de 50%. A relativa baixa diluiÃÃo encontrada e o elevado reforÃo reduziram a necessidade de uma segunda camada, o que torna o processo uma boa opÃÃo para operaÃÃes de revestimento para indÃstria de petrÃleo e gÃs. / Weld overlayâs Nickel based alloy are used by the oil and gas industry as an option for construction and repair of structures and equipment subjected to severe environment conditions with the purpose to provide performance required like for corrosion resistance. Many works have been developed with Nickel based superalloys AWS ERNiCrMo-3, AWS ERNiCrMo-4 e AWS ERNiCrMo-14, evaluating among several characteristics the last alloy proved to be upper, but their cost is also higher than the other two. Therefore the present work intends to combine the high productivity of GMAW double wire for welding overlay applications using alloy with AWS ERNiCrMo-3, AWS ERNiCrMo-4 with the intention of obtain a mixture presenting both chemical composition similar to the AWS ER NiCrMo-14 such as corrosion resistance performance, but with less cost. Exploratory studies were performed by means of welding with simple deposition to determine the range of welding speed between 50 and 100 cm / min, the operating mode of the source constant current and pulsed pure argon shielding gas. The coatings were welded with low energy (7,56 kJ/cm), triangle weaving, electrodes positioned one behind the other in relation to the welding speed, without out of phase the currents. This step was varied angle of attack and the percentage of overlap the weld beads. The best condition was presented lower dilution, 9.75%, and a high thickness 3.92 mm and that obtained using the torch inclined at 15  and overlap of 50%. The relatively low dilution and high thickness found reduced the need for a second coating, which makes the process a good option for coating operations.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-08-14T12:53:45Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE_Versão_depósito na central.pdf: 5398168 bytes, checksum: 86dabd444bb2e345c6039ecb024634b1 (MD5) / Made available in DSpace on 2017-08-14T12:53:45Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE_Versão_depósito na central.pdf: 5398168 bytes, checksum: 86dabd444bb2e345c6039ecb024634b1 (MD5) Previous issue date: 2016-05-24 / CNPQ / Ao considerar o contexto dos estudos sobre Turismo de Base Comunitária (TBC) e a evidência da governança como um dos fatores limitantes à consolidação de experiências turísticas de base comunitária, esta tese defende que a governança condiciona a reprodução dos princípios de participação e protagonismo comunitário, centrais às discussões do TBC. Dessa maneira, o objetivo geral desta tese é propor um modelo de análise da governança do TBC (MAG do TBC). Considerando uma perspectiva metodológica qualitativa baseada na teoria adaptativa de Layder (1993; 1998), o caminho metodológico compreendeu quatro fases distintas, nas quais fazem parte: uma pesquisa bibliográfica, duas consultas a especialistas por meio de grupo de discussões e verificação empírica do modelo em uma experiência de turismo consolidada, a Associação Acolhida na Colônia, sediada no município de Santa Rosa de Lima -SC. Ademais, a verificação empírica do MAG do TBC no campo possibilitou a emergência de novos critérios que foram incorporados à versão final do modelo. Os dados oriundos destas fases do estudo foram examinados e discutidos a partir da análise do conteúdo categorial. Desse modo, propõese que a análise da governança em experiências turística de TBC consolidadas seja analisada com base em três dimensões da governança, a saber: participação, transparência e eficácia. A operacionalização da análise destas dimensões se dá por meio da sistematização de elementos constituintes e seus critérios de análise, inerentes a cada dimensão supracitada. / Considering the context of the studies about Communitarian Based Tourism (CBT) and the evidence of governance as one of the limiting factors to the consolidation of the CBT experiences, this thesis defends that the governance influences the reproducing of the principles of participation and communitarian protagonism, central to CBT discussions. This way, the general aim of this research is propose a model of governance analysis of the CBT (MAG of TCB). Considering a qualitative methodology perspective based on adaptive theory of Layder (2993; 1998), the methodological way comprehended four different phases, which are composed by: bibliographical research, two queries to specialists through discussing groups and empiric verification of the model in an experience of consolidated tourism, the Association Acolhida na Colônia, placed in the city Santa Rosa de Lima-SC. Moreover, the empiric verification of the MAG of TBC in the field enabled the emergency of new criteria that were incorporated to final version of the model. The data from these phases of the study were examined and discussed from the analysis of categorical subject. This way, it is proposed that the analysis of governance in consolidated TBC touristic experience is analyzed based in three governance dimensions: participation, transparency and efficiency. The operationalization of these dimensions analysis is given through systematization of constituting elements and its criteria of analysis, inherent to each dimension mentioned above.

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Esta tesis, tomando en consideración las fases mencionadas, pretende abordar la fase 2 “Curso de computación”, para valorar el grado en que el uso de las herramientas computacionales ha facilitado la gestión de su micronegocio a los alumnos egresados del curso.

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Cryopreservation of epididymal spermatozoa may be the only opportunity to preserve valuable genetics of males in cases of unforeseen injury or death. Stallion epididymal spermatozoa have been cryopreserved successfully and it has been demonstrated that stallion epididymal spermatozoa are fertile, and pregnancies as well as live foals have been produced. As spermatozoal quality parameters like motility, morphology and viability have a major influence on fertility and pregnancy rates, it is of great interest to describe these and investigate the influence of seminal plasma on these parameters. Fresh and post-thaw parameters (motility, morphology and viability) of stallion epididymal spermatozoa that have been and that have not been exposed to seminal plasma were evaluated, and directly compared to fresh and post-thaw parameters of ejaculated spermatozoa from the same stallions. Six sperm categories of each stallion (n= 4) were evaluated for motility, morphology and viability. These categories were fresh ejaculated spermatozoa (Fr-E), fresh epididymal spermatozoa that had been exposed to seminal plasma (Fr-SP+), fresh epididymal spermatozoa that had never been exposed to seminal plasma (Fr-SP-), frozen-thawed ejaculated spermatozoa (Cr-E), frozen-thawed epididymal spermatozoa that had been exposed to seminal plasma prior to freezing (Cr-SP+) and frozen-thawed epididymal spermatozoa that had never been exposed to seminal plasma (Cr-SP-). Results show that seminal plasma stimulates initial motility of fresh epididymal stallion spermatozoa while this difference in progressive motility is no longer present post-thaw; and that progressive motility of fresh or frozen-thawed ejaculated stallion spermatozoa is not always a good indicator for post-thaw progressive motility of epididymal spermatozoa. This study shows that seminal plasma has a positive influence on the incidence of overall sperm defects, midpiece reflexes and distal cytoplasmic droplets in frozen-thawed stallion epididymal spermatozoa while the occurance of midpiece reflexes is likely to be linked to distal cytoplasmic droplets. Furthermore, we could show that seminal plasma does not have an influence on viability of fresh and frozen-thawed morphologically normal epididymal spermatozoa. In conclusion, we recommend the retrograde flushing technique using seminal plasma as flushing medium to harvest and freeze stallion epididymal spermatozoa. AFRIKAANS : Bevriesing van epididimale spermatozoa mag die enigste geleentheid wees om waardevolle genetika van manlike diere te bewaar in die geval van onverwagse dood of besering. Epididimale spermatozoa van hingste is al suksesvol bevries, is bewys vrugbaar te wees en dragtighede sowel as lewendige vullens is deur die gebruik daarvan gelewer. Aangesien maatstawwe van spermgehalte soos beweeglikheid, morfologie en lewensvatbaarheid ‘n beduidende invloed uitoefen op vrugbaarheid en dragtigheidsyfers, is dit van groot belang om hierdie maatstawwe te omskryf en die invloed van seminale plasma daarop te ondersoek. Vars en ontdooide maatstawwe (beweeglikheid, morfologie en lewensvatbaarheid) van hings epididimale spermatozoa wat of aan seminal plasma blootgestel is of nie, is vergelyk met vars en ontdooide maatstawwe van geejakuleerde spermatozoa. Ses spermkategorieë van elke hings (n=4) is geevalueer vir beweeglikheid, morfologie en lewensvatbaarheid. Die kategorieë was vars geejakuleerde spermatozoa (Fr-E), vars epididimale spermatozoa wat blootgestel is aan seminale plasma (Fr-SP+), vars epididimale spermatozoa sonder blootstelling aan seminale plasma (Fr-SP-), ontdooide geejakuleerde spermatozoa (Cr-E), ontdooide epididimale spermatozoa blootgestel aan seminale plasma voor bevriesing (Cr-SP+) en ontdooide epididimale spermatozoa wat nooit blootgestel is aan seminale plasma nie (Cr-SP-). Uitslae toon dat seminale plasma die aanvanklike beweeglikheid van vars epididimale hings spermatozoa stimuleer, terwyl die verskil in lynbeweeglikheid nie meer teenwoordig is na ontdooiing nie; dat lynbeweeglikheid van vars epididimale spermatozoa of ontdooide geejakuleerde hings spermatozoa nie altyd ‘n goeie aanduiding is vir lynbeweeglikheid na ontdooiing nie. Hierdie studie toon dat seminale plasma ‘n positiewe invloed het op die voorkoms van algehele spermdefekte, midstukreflekse en distale sitoplasmiese druppeltjies in ontdooide hings epididimale spermatozoa terwyl die voorkoms van midstuk reflekse waarskynlik verband hou met distale sitoplasmiese druppletjies. Verder kon ons ook aantoon dat seminale plasma geen invloed het op die lewensvatbaarheid van vars en ontdooide morfologies normale epididimale spermatozoa nie. Ten slotte beveel ons aan dat retrograadse spoeling met seminale plasma as spoelmedium gebruik word wanneer hings epididimale spermatozoa versamel en bevries word. / Dissertation (MSc)--University of Pretoria, 2010. / Production Animal Studies / unrestricted