Made available in DSpace on 2014-10-09T12:41:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:34Z (GMT). No. of bitstreams: 0 / O objetivo deste trabalho foi desenvolver um software, de fácil operação e eficiente, para determinar a difusividade térmica de biomateriais. A necessidade de se conhecer a difusividade térmica de materiais como, por exemplo, esmalte e dentina, é essencial para o estabelecimento de protocolos de utilização clínica laser, para evitar danos colaterais ao paciente. O software desenvolvido, denominado CZ ThermaDiff, baseia-se no processamento de imagens térmicas adquiridas por uma câmera termográfica no infravermelho (ThermaCam SC3000, FLIR System, EUA). Foi desenvolvido em ambiente LabView, o que permitiu criar um painel de controle de fácil operação, contendo apenas duas funções básicas (Start e Stop). O software arquiva os dados em formato de tabela contendo todas as medidas de difusividade térmica, suas médias para intervalos de 10 °C e suas respectivas temperaturas, para uma amostra. Foi observado, tanto para o esmalte quanto para a dentina, que os valores de difusividade não são constantes e aumentavam em função da temperatura. Os valores encontrados foram aplicados a um modelo de transferência de calor, simulando um dente molar humano com as seguintes estruturas: esmalte, dentina e polpa. O modelo baseia-se no método de resistores térmicos, sendo que para a polpa foi utilizado o modelo de difusão de calor, considerando a circulação sanguínea. Os valores de temperatura obtidos neste modelo teórico, utilizando difusividades dependentes da temperatura foram maiores que as obtidas com um valor constante de difusividade, medido à temperatura ambiente. Este fato realça a importância da mensuração da difusividade em função da temperatura e da interface desenvolvida neste trabalho. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-09-23T14:38:49Z No. of bitstreams: 2 Dissertação - Patricia da Silva Pimenta - 2016.pdf: 2330303 bytes, checksum: 4da8aefb2ebbff252aebb46b4e2ececd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-26T11:55:48Z (GMT) No. of bitstreams: 2 Dissertação - Patricia da Silva Pimenta - 2016.pdf: 2330303 bytes, checksum: 4da8aefb2ebbff252aebb46b4e2ececd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-26T11:55:48Z (GMT). No. of bitstreams: 2 Dissertação - Patricia da Silva Pimenta - 2016.pdf: 2330303 bytes, checksum: 4da8aefb2ebbff252aebb46b4e2ececd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-08-26 / The increase in livestock production demand has required that animals are increasingly adverse weather conditions more suited to express the maximum of genetics, nutrition and management received. So, identify, and evaluate mensure animals more adapted breeds is an aspect to be explored. The Senepol breed was formed by British breeds (Red Poll) and African (N'Dama) to obtain a suitable animal. This study aimed to measure the climate and physiological variables to determine the index of tolerance Steers heat of Senepol race. The animals were submitted to thermolytic capacity test checking the most suitable hot weather. The experiment was conducted in Genetic Alge plantation in Nerópolis - GO, during the summer months. 17 steers average age of 12 months analyzed the sun and the shade durnte 3 nonconsecutive days of spring and summer were used. completely randomized design and and analyzed by Tukey's test at 5% and the average for simple correlation was used. The meteorological variables indicated that the animals could present stress by ITU bands that recorded values between 78 and 80 and the shade 99 and 106 to the sun. However, the physiological conditions results showed no significant differences (P> 0.05). Significant differences (P> 0.05) between the means of the animals were observed when the animals in the shade and then returned to the sun. The animals showed significant results (P> 0.05) to return to thermal comfort when, after sun returned to the shadow as verified by TSC with averages of 37ºC in the shade and the sun 39ºC. In addition, correlations between means showed that when the animal featured most TSC and ICT also had higher TR and FR. In most ICT average was 10.17 and 9.7 indicating the lowest adapted to heat. It was concluded from this work that the Senepol breed showed good tolerance to heat and can be a tool for selecting programs as well as in industrial intersections prove adapted to the climatic conditions in Goiás. / aumento na demanda da produção pecuária tem exigido que os animais sejam cada vez mais adaptados as condições adversas do clima para expressar o máximo da genética, nutrição e manejo recebidos. Assim, identificar, mensurar e avaliar animais de raças mais adaptadas é uma vertente a ser explorada. A raça Senepolfoi formada pelas raças britânicas (Red Poll) e africana (N´Dama) com a obtenção de um animal adaptado. Esse trabalho objetivou-se mensurar as variáveis climáticas e fisiológicas para determinar o índice de tolerância ao calor de Novilhos da raça Senepol. Os animais foram submetidos ao teste de capacidade termolítica verificando os mais adaptados ao clima quente. O experimento foi realizado na fazenda Alge Genética no município de Nerópolis – GO, durante meses de verão. Foram utilizados 17 novilhos de idade média de 12 meses analisados ao sol e à sombra durnte 3 dias não consecutivos de primavera e verão. Foi utilizado delineamento inteiramente casualisado e e os dados analisados pelo teste de Tukey a 5% e as médias por correlação simples. As variáveis meteorológicas indicaram que os animais poderiam apresentar estresse pelas faixas de ITU que registraram valores entre 78 e 80 a sombra e 99 e 106 ao sol. No entanto, as condições fisiológicas não apresentaram resultados com diferenças significativas (P>0,05). As diferenças significativas (P>0,05) entre as médias dos animais foram constatadas quando os animais à sombra e depois de retornaram ao Sol. Os animais apresentaram resultados significativos (P>0,05) de retorno ao conforto térmico quando, depois do Sol retornaram à sombra como foi verificado pela TSC com médias à sombra de 37ºC e ao sol de 39ºC. Além disso, as correlações entre as médias mostraram que quando o animal apresetava maior TSC e TIC também apresentava maior TR e FR. No ICT a maior média foi 10,17 e o menor 9,7 indicando adaptação ao calor. Concluiu-se com esse trabalho que a raça Senepol apresentou boa tolerância ao calor e pode ser uma ferramenta para os programas de seleção bem como nos cruzamentos industriais por se mostrarem adaptados as condições climáticas em Goiás.

Les matériaux composites sont largement utilisés dans l'industrie en raison de leur bonne tenue mécanique et de leur faible densité. La diversité des domaines d’application des matériaux composites donne lieu à une grande variété de modes de sollicitation et d’endommagement. De ce fait, l’évaluation de leurs propriétés et le contrôle de leur état présentent un grand intérêt industriel. Dans ce travail, une nouvelle méthode d’évaluation et de contrôle non destructif dite par sonothermographie est explorée. Cette méthode est basée sur l'analyse du champ thermique induit par des ondes ultrasonores de puissance dans les matériaux absorbants tels que les composites. Deux applications complémentaires sont étudiées, d’une part l’évaluation des propriétés thermiques du matériau et d’autre part le contrôle non destructif de structures par thermographie infrarouge. Dans ce cadre, le problème direct de la sonothermographie est résolu numériquement à partir d’un modèle par éléments finis. Ce modèle permet de simuler le champ thermique induit par la propagation d’ondes ultrasonores dans un matériau absorbant dont les propriétés sont connues. Les simulations réalisées permettent de montrer l’applicabilité de la sonothermographie à la détection de défauts. Une nouvelle approche de caractérisation thermique est également développée. Cette approche basée sur la formulation faible de l’équation de conduction de la chaleur permet une estimation robuste de la diffusivité thermique du matériau à partir du champ thermique induit par les ondes ultrasonores de puissance. Des résultats expérimentaux sont présentés pour le cas de plaques minces. / The composite materials are widely used in industry because of their high mechanical resistance and low density. The diversity of composite materials application fields gives rise to a large variety of solicitation and damage conditions. For this reason, the evaluation of their properties and their health monitoring are of great industrial interest. In this work, a new method of evaluation and non-destructive testing named sonothermography is explored. This method is based on the analysis of thermal fields induced by ultrasonic waves in absorbent materials such as composites. Two additional applications are studied: the evaluation of the thermal properties of the material and the non-destructive testing of structures by infrared thermography. In this framework, the direct problem of sonothermography is solved numerically using a model based on the finite element method. This model allows to simulate the thermal field induced by the propagation of ultrasonic waves in absorbent material whose properties are known. The simulations carried out show the applicability of the sonothermography for the detection of defects. An innovative approach for thermal characterization is also developed. This approach based on the weak formulation of the heat conduction equation allows a robust estimate of the thermal diffusivity of the material from the thermal field induced by ultrasonic waves. Experimental results are presented for thin plates.

Dans le domaine du Génie Civil, de nombreuses méthodes d’auscultation sont développées. Elles visent à aider à l’évaluation de l’état des ouvrages d’art en donnant des informations sur la structure interne ou sur l’état des matériaux. Les techniques basées sur la thermographie infrarouge sont prometteuses, elles présentent l’intérêt d’être à grand rendement et de se traduire par l’observation d’images (thermogrammes) qui semblent plus accessibles. La thèse consiste au développement d’une méthode de thermographie infrarouge active en basant sur un système d’excitation micro-ondes conçu et réalisé pour cette étude.La source micro-ondes a été réalisée sur la base d’un magnétron commercial de 800 W à 2.45 GHz associé à une antenne cornet pyramidal pour guider les ondes vers des éléments à chauffer. Par rapport aux sources utilisées classiquement en thermographie infrarouge active, les ondes électromagnétiques de type micro-ondes se propagent dans le volume d’un élément en béton. Les ondes subissent des réflexions et des effets de diffraction lorsque impactent des parties métalliques. Des phénomènes d’interférence peuvent apparaître en surface et par effet radiothermique générer des gradients de température observables par thermographie infrarouge. Ces effets se produisent de façon instantanée. En prenant en compte de toutes les consignes de sécurité, des essais avec ce nouveau système d’excitation ont été effectués dans une enceinte de protection haute fréquence. Cette nouvelle méthode a été appliquée à la détection de défauts (absence de colle) dans le cas d’un renforcement composite (CFRP), d’une pièce métallique derrière une plaque de bois d’un centimètre d’épaisseur, et plus particulièrement des armatures verticales / In the field of Civil Engineering, many inspection methods have been developed. They are intended to evaluate the condition of structures by providing information about the internal structure or status of the materials. Techniques based on infrared thermography are promising as they have the advantage of giving high performances and results by the thermograms observation that seems more accessible. The objective of the thesis is to develop a new active infrared thermography method based on a microwave excitation system designed and built for this study.The microwave source was set up based on a commercial magnetron 800 W at2.45 GHz associated to a pyramidal horn antenna for guiding microwave radiation to the heated elements. Compared to other sources traditionally used in active infrared thermography, the microwaves can propagate into the volume of a concrete element. The waves undergo the reflection and the diffraction effects while they impact any metal parts. The interference phenomena can appear on the surface and generate, by the radiothermal effect, the temperature gradients observed by infrared thermography. These effects occur instantaneously. Considering all the safety, the tests with the new excitation system were carried out in a high frequency protection cell. This new method has been applied to the defect detection (adhesive absence) in the case of a composite reinforcement (CFRP), a metal element behind a wooden plate of one centimeter of thickness, and more particularly the vertical reinforcement bars in a reinforced concrete wall.

Le but de cette étude est de proposer un modèle combiné au transfert de chaleur dans la veine et des tissus de la peau humaine. Il permet de mieux comprendre le comportement thermomécanique de la peau et de son environnement direct lorsqu'ils sont exposés à de fortes variations thermiques. Le travail est basé sur des études expérimentales et numériques. La première étape expérimentale consiste à placer une barre d'acier cylindrique refroidie ou réchauffée sur la peau d'un avant-bras humain et en mesurant l'évolution de température en utilisant une caméra infrarouge. L'influence de la circulation sanguine dans les veines sur la diffusion de la chaleur est très nettement.La deuxième étape expérimentale consiste à mesurer les propriétés géométriques des veines et la vitesse du sang en utilisant une sonde d'écho-Doppler. Ces mesures expérimentales fournissent un modèle numérique de la peau et de son environnement direct. Le modèle tridimensionnel multicouche utilise l'équation biothermique de Pennes pour modéliser les tissus et celle de la chaleur dans un fluide pour modéliser le sang. Les propriétés des matériaux sont tirées de la littérature et validées par notre expérimentation. Le modèle numérique permet de retrouver les mesures expérimentales, mais aussi d'accéder à la température et à la vitesse du sang dans les veines. Enfin, un modèle numérique d'endommagement thermique, couplé au modèle multicouche de la peau, a été développé dans cette étude. Il permet de simuler l'endommagement suite à une brûlure de la peau et de tester l'efficacité de différents traitements visant à limiter les lésions. / The aim of this study is to propose a combined model of heat transfer in the vein and tissue of human skin. It allows to better understand the thermomechanical behavior of the skin and its direct environment when exposed to strong thermal variations. The work is based on experimental and numerical investigations. The first experimental step consists in placing a cooled or a heated cylindrical steel bar on the skin of a human forearm and measuring the temperature change using an infrared camera. Blood circulation in the veins was seen to clearly influence heat diffusion. The second experimental step consists in measuring geometrical properties of the veins and blood velocity using an echo-Doppler probe. These experimental measurements provide a numerical model of the skin and its direct vicinity. The three-dimensional multilayer model uses Pennes equation to model biological tissue and the convective heat transport equation, to model blood. The properties of the biological materials obtained from the literature are validated by our experimentation. The numerical model is able to simulate the experimental observations, but also to estimate blood temperature and velocity in the veins. Finally, a numerical model of thermal damage, coupled with the multilayer model of skin, was developed in this study. It simulates the damage due to burning of the skin and to test the efficacy of different treatments to limit the damage.

Submitted by Adriana Martinez (amartinez@unoeste.br) on 2017-09-05T12:53:44Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Luci.pdf: 503217 bytes, checksum: bcb750cc3835332fed12d8730ecb4254 (MD5) / Made available in DSpace on 2017-09-05T12:53:44Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Luci.pdf: 503217 bytes, checksum: bcb750cc3835332fed12d8730ecb4254 (MD5) Previous issue date: 2017-06-22 / This work aims to study the effects of omega 3 and / or vitamin B12 administration on sperm and histomorphometric parameters of the reproductive organs of Wistar rats and their correlation with the temperature of these regions. Sixteen rats were divided into four groups (n = 4 per group) who received daily injections for 30 days, being: Control Group - saline solution; Group Omega three- fish oil (Equaliv®) 1g / kg; Group B12 - vitamin B12 (Monovin B12 ®) 3μg; And Group Omega + B12 - fish oil 1g / kg and vitamin B12 3μg. Analyzed sperm morphology and the histomorphometries were evaluated by the Motic Images Plus® version 2.0 program. On a daily basis, thermographic images of areas of the body (FLIR E40®, Sweden) were analyzed and analyzed by the Flir Tools 2.1® program. Data were submitted to analysis of variance and Tukey test at 5%. Omega 3 reduced the seminiferous epithelium and B12 minimized this deleterious effect (P ≤ 0.05). The surface temperature of the scrotum was higher in group B12 (P ≤0.05). There was a high positive correlation between scrotum surface temperature and distal cytoplasmic droplet percentage (P = 0.678). / Este trabalho tem como objetivo estudar os efeitos da administração do ômega três e/ou vitamina B12 sobre parâmetros espermáticos e histomorfométricos dos órgãos reprodutivos de ratos Wistar e sua correlação com a temperatura dessas regiões. Utilizou-se 16 ratos, divididos em quatro grupos (n=4 por grupo) que receberam injeções diárias por 30 dias, sendo: Grupo Controle – solução salina; Grupo Ômega três– óleo de peixe (Equaliv®) 1g/kg; Grupo B12 – vitamina B12 (Monovin B12®) 3µg; e Grupo Ômega + B12 – óleo de peixe 1g/kg e vitamina B12 3µg. Analisados morfologia espermática e as histomorfometrias foram avaliados pelo programa Motic Images Plus® versão 2.0. Diariamente, foram obtidas imagens termográficas de áreas do corpo (FLIR E40®, Suécia) e analisadas pelo programa Flir Tools 2.1®. Os dados foram submetidos à análise de variância e teste de Tukey a 5%. O ômega 3 reduziu o epitélio seminífero e a B12 minimizou esse efeito deletério (P ≤ 0,05). A temperatura da superfície do escroto foi superior no grupo B12 (P ≤0,05). Houve alta correlação positiva entre temperatura da superfície do escroto e porcentagem de gota citoplasmática distal (P = 0,678).

Submitted by Michele Mologni (mologni@unoeste.br) on 2018-11-22T11:15:18Z No. of bitstreams: 1 Camila Dutra de Souza Francisquini.pdf: 2946141 bytes, checksum: d4a8301da20ac5338becde2b5af3e95b (MD5) / Made available in DSpace on 2018-11-22T11:15:18Z (GMT). No. of bitstreams: 1 Camila Dutra de Souza Francisquini.pdf: 2946141 bytes, checksum: d4a8301da20ac5338becde2b5af3e95b (MD5) Previous issue date: 2018-10-10 / In regions of tropical climate, mating occurs during warmer months, bulls are subject to environmental variations that interfere with their fertility and reproductive efficacy of the herd. The use of some biotechnologies contributes to the efficiency of the production system and to evaluate the fertilization potential of a semen sample, be it fresh, chilled or frozen. A combination of several analyzes and seminal assay methods offers greater accuracy to define a complex functionality. For Chapter 1, the objectives of the study were: (1) to evaluate the effect of the seasons on the surface temperature of the scrotum and ocular globe, the semen quality and plasma concentration of testosterone from Nellore bulls raised extensively, (2) to verify the plasma protein composition (3) investigate the relationships of these proteins with seminal parameters, surface temperatures of the scrotum and THI. Nellore bulls (n = 20) were evaluated with two data collections with a 30-day interval within each season of the year. Infrared thermography (FLIR E40®) with image analysis (FLIR tools software) for spermatic cord (SCT), proximal pole of the testis (PPT), distal pole of the testis (DPT), tail of the epididymis (TeT) and scrotal temperature gradient (TG), and semen collected and analyzed for quantitative and qualitative characteristics. Blood samples were collected by venipuncture of the jugular to obtain the plasma concentration of testosterone by radioimmunoassay (RIA). The seminal plasma proteins were identified by electrophoresis on SDS-PAGE. The temperature-humidity index (THI) calculated per season. The TG was higher (P <0.05) in autumn (5ºC) and winter (4.4ºC) compared to spring (3.4ºC) and summer (3.7ºC). The THI of spring (73.5) and summer (72) differed (P <0.05) from autumn (64.5) and winter (59.6) and there were correlations (P <0.01) with SCT (0.54), TeT (0.74), PPT (0.71), DPT (0.72) and TG (-0.35). Similarly, MOT (61.5%) and VIG (2.7) in spring were lower in relation to autumn and winter (P <0.05). The plasma concentration of testosterone was higher (P <0.05) in the autumn, in relation to the other seasons of the year. Seminal plasma proteins of 20, 55 and 66KDa contributed positively to seminal quality. The concentration of the protein with 50KDa was high in all seasons, being considered indispensable for the fertility of the bulls. In the spring and summer seasons, in which the THI exceeded the value of 72, there was a decrease in progressive motility and spermatic vigor. The summer and fall, the seasons that presented greater percentages of major and total sperm defects. Ocular globe and scrotal surface temperatures increased in spring and summer and the thermal gradient and testosterone plasma concentration decreased in the same seasons, concluding that the thermal stress with THI above 72 in the spring and summer seasons was sufficient for negatively affect the reproduction of Nelore bulls raised in pasture in the tropics. The chapter 2, the objectives of the study were: (1) assess the quality of refrigerated beef semen transported by 3 hours, passive systems of transport of semen BotuBOX® and BotuFLEX®, diluted in TRIS and BotuBOV®; and (2) evaluate the spermatic kinetics, oxidative stress, mitochondrial potential and cell membrane integrity and acrossomal bovine semen after thawing, diluted in TRIS and BotuBOV® and transported in passive systems semen transport BotuBOX® and BotuFLEX®. The six bulls semen of Nellore breed (Bos taurus indicus), cooled and frozen in 2 extenders TRIS and BotuBOV® and transported in 2 cooling systems BotuBOX® and BotuFLEX®. In a semen sample refrigerated was made a subjective analysis of motility (MOT) and sperm vigor (VIG) and in the sample frozen-thawed, computer-assisted sperm analysis (CASA) and flow cytometry, evaluation of integrity of plasma membrane and acrossomal (IPAM), production of superoxide (O2-) and integrity of cells (IC). On after cooled analysis, the MOT of semen in the BotuBOV® and BotuFLEX® (69.4%) and TRIS and BotuFLEX® (62.9%), were higher (P < 0.05) when compared to the TRIS and BotuBOX®. The largest (P < 0.05) MOT (45.9%) observed in subjective analysis, TM (47.3%) and PM (37%) in the CASA, IPAM (29%), IC (19.8%) and lower production of the O2- (82%) found in the samples frozen-thawed diluted in BotuBOV® extender and transported in the BotuFLEX® system. We conclude that the diluted semen in the BotuBOV® and transported on BotuBOX® or BotuFLEX®, and diluted TRIS extender and transported on BotuFLEX® maintained the viability for using the cooled semen, as well as employment for freezing. The association between the BotuBOV® diluent and refrigerated transport of semen BotuFLEX® presented best effect on the frozen semen in regard to kinetics parameters, integrity of plasma and acrossomal membranes and oxidative stress reduction. / Em regiões de clima tropical, o acasalamento ocorre durante os meses mais quentes, os touros estão sujeitos às variações ambientais que interferem com a sua fertilidade e eficácia reprodutiva do rebanho. A utilização de algumas biotecnologias colabora para a eficiência do sistema de produção e avaliar o potencial de fertilização de uma amostra de sêmen, seja ela fresca, refrigerada ou congelada e Uma combinação de várias análises e métodos de avalição seminal oferece maior acurácia para definir uma complexa funcionalidade. Para o capítulo 1, os objetivos do estudo foram (1) avaliar o efeito das estações do ano na temperatura da superfície do escroto e do globo ocular, na qualidade do sêmen e concentração plasmática de testosterona de touros Nelore criados extensivamente, (2) verificar a composição proteica do plasma seminal em cada estação do ano e as proteínas com maior frequência e (3) investigar as relações dessas proteínas com parâmetros seminais, temperaturas da superfície do escroto e ITU. Touros Nelore (n=20) foram avaliados com duas coletas de dados com intervalo de 30 dias dentro de cada estação do ano, sendo realizados: termografia infravermelha (FLIR E40®) com análise de imagens (software FLIR tools) para cordão espermático (TCE), polo proximal do testículo (PPT), polo distal do testículo (PDT, cauda do epidídimo (TCEp) e gradiente de temperatura escrotal (GT). O sêmen foi coletado e analisado quanto às características quantitativas e qualitativas. Amostras de sangue foram coletadas por venopunção da jugular para obter a concentração plasmática de testosterona por radioimunoensaio (RIA). As proteínas do plasma seminal foram identificadas por eletroforese em SDS-PAGE. O índice de temperatura-umidade (ITU) por estação do ano. O GT foi maior (P<0.05) no outono (5ºC) e inverno (4.4ºC) comparado a primavera (3.4ºC) e verão (3.7ºC). O ITU da primavera (73.5) e verão (72) diferiram (P<0,05) do outono (64.5) e inverno (59.6) e houveram correlações (P<0,01) com TCE (0.54), TCEp (0.74), PPT (0.71), PDT (0.72) e GT (-0.35). Assim como, motilidade espermática (61.5%) e vigor (2.7) na primavera foram inferiores, em relação ao outono e inverno (P<0.05). A concentração plasmática de testosterona foi superior (P<0,05) no outono, em relação às demais estações do ano. As bandas proteicas do plasma seminal de 20, 55 e 66KDa contribuíram de forma positiva para a qualidade seminal. A concentração da banda com 50KDa foi elevada em todas as estações, sendo considerada indispensável para a fertilidade dos touros. Nas estações primavera e verão, nas quais o ITU excedeu o valor de 72, observou-se decréscimo na motilidade progressiva e vigor espermático. O verão e outono, as estações que apresentaram maiores porcentagens de defeitos espermáticos maiores e totais. As temperaturas do globo ocular e da superfície do escroto aumentaram na primavera e verão e o gradiente térmico e a concentração plasmática de testosterona diminuiu nas mesmas estações, concluindo que o estresse térmico com ITU acima de 72, nas estações primavera e verão, foi suficiente para afetar negativamente a reprodução de touros Nelore criados a pasto nos trópicos. Para o capítulo 2, Os objetivos do estudo foram: (1) avaliar a qualidade do sêmen bovino refrigerado transportado por 3 horas, nos sistemas passivos de transporte de sêmen BotuBOX® e BotuFLEX®, diluídos nos meios TRIS e BotuBOV®; e (2) avaliar a cinética espermática, estresse oxidativo, potencial mitocondrial e integridade de membrana plasmática e acrossomal do sêmen bovino pós-descongelação, diluídos nos meios TRIS e BotuBOV® e transportados nos sistemas passivos de transporte de sêmen BotuBOX® e BotuFLEX®. O sêmen de seis touros da raça Nelore (Bos taurus indicus), refrigeradas e congeladas em 2 meios diluentes TRIS e BotuBOV® e transportados em 2 sistemas de refrigeração BotuBOX® e BotuFLEX®. Em uma amostra de sêmen refrigerado foi realizada a análise subjetiva de motilidade (MOT) e vigor (VIG) e na amostra pós-descongelação, realizada a análise computadorizada da motilidade espermática (CASA) e por citometria de fluxo, avaliação de integridade de membrana plasmática e acrossomal (MPA), produção de superóxido (O2) e células íntegras (CI). Na análise pós-refrigeração, a MOT do sêmen na associação BotuBOV® e BotuFLEX® (69.4%) e TRIS e BotuFLEX® (62.9%), foram maiores (P<0.05) quando comparado à TRIS e BotuBOX®. A maior (P<0.05) MOT (45.9%) observada na análise subjetiva, MT (47.3%) e MP (37%) no CASA, MPAI (29%), CI (19.8%) e menor produção de O2- (82%) encontrados nas amostras pós-descongelação diluídas em meio BotuBOV® e transportados no sistema BotuFLEX®. Concluímos que o sêmen diluído no meio BotuBOV® e transportado na BotuBOX® ou BotuFLEX®, e diluído em meio TRIS e transportado na BotuFLEX® mantiveram a viabilidade seminal para uso do sêmen refrigerado, bem como o emprego para a congelação. A associação entre o meio diluente BotuBOV® e o sistema de transporte refrigerado de sêmen BotuFLEX® apresentou melhor efeito sobre o sêmen congelado em relação aos parâmetros de cinética espermática, integridade de membrana plasmática e acrossomal e redução do estresse oxidativo.

Plasma Heat Flux to Solid Structures in Tokamaks Petr Vondráček Energy and particle exhaust is the key issue for future fusion reactors based on magnetic plasma confinement, namely for tokamaks. Good understanding of processes controlling plasma heat fluxes impinging the first wall of tokamaks is of a main concern for fusion research. This doctoral thesis is focused on experimental investigation of plasma heat fluxes in different locations of the COMPASS tokamak. A new infrared thermography system was built for this purpose as a part of this PhD research. There are four main topics studied using the system. First of all, a narrow near-SOL heat flux channel with a very steep radial profile is characterised in HFS limited discharges. It is shown that the near-SOL heat flux decay length is consistent with the drift-based model of the SOL heat transport. Secondly, heat loading of leading edges of misaligned limiters is broadly studied. The optical approximation of the heat flux distribution around a poloidal leading edge is confirmed as a valid approach. Heat loading of a magnetically shadowed side of a toroidal limiter gap is observed experimentally for the first time confirming predictions of particle-in-cell code simulations. Thirdly, localised hot-spots caused by the impact of runaway electrons as well as...

Lorsqu'une structure est soumise à un chargement thermique hétérogène, des dilatations empêchées génératrices de contraintes surviennent. Lorsque ces sollicitations sont répétées un grand nombre de fois, un endommagement puis une fissuration du matériau peuvent apparaître. On parle alors de fatigue thermique du matériau. Ce phénomène, jugé responsable de différents incidents rencontrés dans les zones de mélange entre fluides chaud et froid des centrales nucléaires a fait l'objet de nombreuses études lancées au sein de projets successifs pilotés par EDF. Ces études portaient sur la détermination des chargements thermo-hydrauliques dans les zones de mélange, le transfert de chaleur à la structure, la résolution du problème thermomécanique permettant de connaître les champs de contrainte et de déformation en tout point de la structure et enfin la résistance du matériau (un acier inoxydable austénitique AISI 304L)soumis à de telles sollicitations. Concernant ce dernier aspect, plusieurs types d'essais ont été réalisés : d'une part, des essais de fatigue uniaxiaux et isothermes pour construire une courbe de fatigue mécanique du matériau et, d'autre part, des essais sur plusieurs dispositifs expérimentaux de fatigue thermique développés au sein d'organismes de recherche (CEA, EDF, JRC, JAEA,…) pour s'approcher des conditions de service. L'interprétation de ces derniers essais passe par l'estimation des champs de température et de déplacement dans la structure à partir de quelques mesures ponctuelles de température par thermocouples. On constate alors que les premières fissures s'amorcent en fatigue thermique pour un nombre de cycles sensiblement inférieur à celui estimé à partir des courbes de fatigue mécanique du matériau et de l'amplitude maximale de déformation équivalente estimée dans les essais de fatigue thermique. L'objet de ce travail de thèse consiste donc à concevoir et à réaliser des chocs thermiques sur un matériau de structure couplés à des mesures synchrones et sans contact de champs de température et de déplacement au niveau de la surface endommagée. Les chocs thermiques seront réalisés à l'aide d'un laser de puissance dont la longueur d'onde sort du spectre utilisé par la caméra infrarouge qui mesure le champ de température de surface de telle manière que le dépôt d'énergie n'affecte pas les mesures de température. Plusieurs pistes sont envisagées selon que les champs sont mesurés uniquement avec la caméra infrarouge ou en utilisant deux caméras, l'une travaillant dans l'infrarouge et l'autre dans le visible. Dans les deux cas de figure, l'absorptivité et l'émissivité de la surface soumise au choc thermique doivent être optimisées pour permettre d'avoir à la fois un dépôt d'énergie homogène par laser et une mesure précise des champs thermomécaniques. Une difficulté qu'il conviendra de surmonter est d'obtenir un champ d'émissivité de surface représentant un compromis acceptable entre une émissivité forte et homogène dans l'infrarouge pour des mesures de température et une émissivité hétérogène (dans l'infrarouge ou le visible selon la caméra utilisée) pour créer un contraste de niveau de gris indispensable aux mesures de déplacement par corrélation d'images. Parallèlement aux essais,des simulations numériques thermomécaniques seront également réalisées pour compléter ces champs en volume et tester l'influence des conditions aux limites. L'objectif final de la thèse est d'obtenir pour la première fois une mesure fiable des quantités d'intérêt dans une zone d'amorçage en fatigue thermique et ainsi pouvoir quantifier convenablement un éventuel effet aggravant des sollicitations de fatigue thermique. / Thermal fatigue occurs in nuclear power plant pipes. The temperature variations are due to the turbulent mixing of fluids that have different temperatures. Many experimental setups have been designed but the measured temperatures have only been punctual and out of the zone of interest (e.g., via thermocouples). The equivalent strain variation in the crack initiation region is calculated with numerical thermomechanical simulations. In many cases, the comparisons between numerical and experimental results have shown that the crack initiation predictions in thermal fatigue are non-conservative. A new testing setup is proposed where thermal shocks are applied with a pulsed laser beam while the thermal and kinematic fields on the specimen surface are measured with infrared (IR) and visible cameras, respectively. Experimental testings are performed and different measurement techniques for temperature and kinematic fields are used. IR camera and pyrometers allow to measure the temperature variations in the zone impacted by the laser beam. To estimate the absolute temperature, the surface emissivities at the respective wavelengths are determined by different methods. The absolute temperature field is then used to apply the actual thermal loading in a decoupled FE model after an identification process of the parameters of the laser beam. Once the thermal loading is generated based upon the experimental data, the stress and strain fields can be computed in the region of interest with an elastoplastic law.The experimental strain variations calculated from the DIC measurements are compared with the predictions obtained with the FE simulation.

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