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Les dynamiques du rapprochement communautaire à chypre depuis 1974 / The dynamics of community reconciliation in Cyprus since 1974Lapierre, Alexandre 21 January 2016 (has links)
Cette thèse Çtudie les rapprochements bi-communautaires dans la société civile à Chypre depuis 1974, les mouvements concernés, leurs membres, leurs actions, leurs réussites et leurs difficultés face à des nationalismes vigoureux dans une île coupé en deux hermétiquement jusqu'en 2003. Ces mouvements ne peuvent être coupés de leur contexte, les négociations infructueuses sous l'égide des Nations Unies, le développement des nationalismes, l'influence pesante des Mères-Patries. Il convient également de prendre en compte le passage du temps, les jeunes adultes de 2015 n'ont pas connu les affrontements de 1964 ni l'invasion turque de 1974. / This thesis studies the bicommunal reconciliation movements in Cyprus born in the civil society since 1974, the associations concerned, their members, theirs actions, their success or difficulties in front of vigorous nationalisms in an island tightly halved in two until 2003. Of course these movements cannot be separated from their context, the unsuccessful negotiations under the aegis of the United Nations, the development of nationalisms, the heavy influence of the Mother Countries. We must also take into account the passage of time, the young adults of 2015 have lived neither the 1964 bicommunal clashes nor the 1974 Turk invasion.
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The mixed Ax-Lindemann theorem and its applications to the Zilber-Pink conjecture / Le théorème d’Ax-Lindemann mixte et ses applications à la conjecture de Zilber-PinkGao, Ziyang 24 November 2014 (has links)
La conjecture de Zilber-Pink est une conjecture diophantienne concernant les intersections atypiques dans les variétés de Shimura mixtes. C’est une généralisation commune de la conjecture d’André-Oort et de la conjecture de Mordell-Lang. Le but de cette thèse est d’étudier Zilber-Pink. Plus concrètement, nous étudions la conjecture d’André-Oort, selon laquelle une sous-variété d’une variété de Shimura mixte est spéciale si son intersection avec l’ensemble des points spéciaux est dense, et la conjecture d’André-Pink-Zannier, selon laquelle une sous-variété d’une variété de Shimura mixte est faiblement spéciale si son intersection avec une orbite de Hecke généralisée est dense. Cette dernière conjecture généralise Mordell-Lang comme expliqué par Pink.Dans la méthode de Pila-Zannier, un point clef pour étudier la conjecture de Zilber-Pink est de démontrer le théorème d’Ax-Lindemann qui est une généralisation du théorème classique de Lindemann-Weierstrass dans un cadre fonctionnel. Un des résultats principaux de cette thèse est la démonstration du théorème d’Ax-Lindemann dans sa forme la plus générale, c’est- à-dire le théorème d’Ax-Lindemann mixte. Ceci généralise les résultats de Pila, Pila-Tsimerman, Ullmo-Yafaev et Klingler-Ullmo-Yafaev concernant Ax-Lindemann pour les variétés de Shimura pures.Un autre résultat de cette thèse est la démonstration de la conjecture d’André-Oort pour une grande collection de variétés de Shimura mixtes : in- conditionnellement pour une variété de Shimura mixte arbitraire dont la par- tie pure est une sous-variété de AN6 (par exemple les produits des familles universelles des variétés abéliennes de dimension 6 et le fibré de Poincaré sur A6) et sous GRH pour toutes les variétés de Shimura mixtes de type abélien. Ceci généralise des théorèmes connus de Klinger-Ullmo-Yafaev, Pila, Pila-Tsimerman et Ullmo pour les variétés de Shimura pures.Quant à la conjecture d’André-Pink-Zannier, nous démontrons plusieurs cas valables lorsque la variété de Shimura mixte ambiante est la famille universelle des variétés abéliennes. Tout d’abord nous démontrons l’intersection d’André-Oort et André-Pink-Zannier, c’est-à-dire que l’on étudie l’orbite de Hecke généralisée d’un point spécial. Ceci généralise des résultats d’Edixhoven-Yafaev et Klingler-Ullmo-Yafaev pour Ag. Nous prouvons ensuite la conjecture dans le cas suivant : une sous-variété d’un schéma abélien au dessus d’une courbe est faiblement spéciale si son intersection avec l’orbite de Hecke généralisée d’un point de torsion d’une fibre non CM est Zariski dense. Finalement pour une orbite de Hecke généralisée d’un point algébrique arbitraire, nous démontrons la conjecture pour toutes les courbes. Ces deux derniers cas généralisent des résultats de Habegger-Pila et Orr pour Ag.Dans toutes les démonstrations, la théorie o-minimale, en particulier le théorème de comptage de Pila-Wilkie, joue un rôle important. / The Zilber-Pink conjecture is a diophantine conjecture concerning unlikely intersections in mixed Shimura varieties. It is a common generalization of the André-Oort conjecture and the Mordell-Lang conjecture. This dissertation is aimed to study the Zilber-Pink conjecture. More concretely, we will study the André-Oort conjecture, which predicts that a subvariety of a mixed Shimura variety having dense intersection with the set of special points is special, and the André-Pink-Zannier conjecture which predicts that a subvariety of a mixed Shimura variety having dense intersection with a generalized Hecke orbit is weakly special. The latter conjecture generalizes the Mordell-Lang conjecture as explained by Pink.In the Pila-Zannier method, a key point to study the Zilber-Pink conjec- ture is to prove the Ax-Lindemann theorem, which is a generalization of the functional analogue of the classical Lindemann-Weierstrass theorem. One of the main results of this dissertation is to prove the Ax-Lindemann theorem in its most general form, i.e. the mixed Ax-Lindemann theorem. This generalizes results of Pila, Pila-Tsimerman, Ullmo-Yafaev and Klingler-Ullmo-Yafaev concerning the Ax-Lindemann theorem for pure Shimura varieties.Another main result of this dissertation is to prove the André-Oort conjecture for a large class of mixed Shimura varieties: unconditionally for any mixed Shimura variety whose pure part is a subvariety of AN6 (e.g. products of universal families of abelian varieties of dimension 6 and the Poincaré bundle over A6) and under GRH for all mixed Shimura varieties of abelian type. This generalizes existing theorems of Klinger-Ullmo-Yafaev, Pila, Pila-Tsimerman and Ullmo concerning pure Shimura varieties.As for the André-Pink-Zannier conjecture, we prove several cases when the ambient mixed Shimura variety is the universal family of abelian varieties. First we prove the overlap of André-Oort and André-Pink-Zannier, i.e. we study the generalized Hecke orbit of a special point. This generalizes results of Edixhoven-Yafaev and Klingler-Ullmo-Yafaev for Ag. Secondly we prove the conjecture in the following case: a subvariety of an abelian scheme over a curve is weakly special if its intersection with the generalized Hecke orbit of a torsion point of a non CM fiber is Zariski dense. Finally for the generalized Hecke orbit of an arbitrary algebraic point, we prove the conjecture for curves. These generalize existing results of Habegger-Pila and Orr for Ag.In all these proofs, the o-minimal theory, in particular the Pila-Wilkie counting theorems, plays an important role.
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Les dynamiques du rapprochement communautaire à Chypre depuis 1974 / The dynamics of community reconciliation in Cyprus since 1974Lapierre, Alexandre 21 January 2016 (has links)
Cette thèse étudie les rapprochements bi-communautaires dans la société civile à Chypre depuis 1974, les mouvements concernés, leurs membres, leurs actions, leurs réussites et leurs difficultés face à des nationalismes vigoureux dans une île coupée en deux hermétiquement jusqu'en 2003. Ces mouvements ne peuvent être coupés de leur contexte, les négociations infructueuses sous l'égide des Nations Unies, le développement des nationalismes, l'influence pesante des Mères-Patries. Il convient également de prendre en compte le passage du temps, les jeunes adultes de 2015 n'ont pas connu les affrontements de 1964 ni l'invasion turque de 1974. / This thesis studies the bicommunal reconciliation movements in Cyprus born in the civil society since 1974, the associations concerned, their members, theirs actions, their success or difficulties in front of vigorous nationalisms in an island tightly halved in two until 2003. Of course these movements cannot be separated from their context, the unsuccessful negotiations under the aegis of the United Nations, the development of nationalisms, the heavy influence of the Mother Countries. We must also take into account the passage of time, the young adults of 2015 have lived neither the 1964 bicommunal clashes nor the 1974 Turk invasion.
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Aplicação da microtomografia computadorizada para a análise morfométrica bi e tridimensional na avaliação da perda óssea experimental em ratos / Use of micro-computed tomography in two and three-dimensional morphometric analyses for experimental bone loss evaluation in ratsFernandes, Patricia Garani 04 June 2014 (has links)
Introdução: A histomorfometria do osso é um dos métodos padronizados que pode ser utilizado para quantificar a microestrutura do osso trabecular. Existem muitos meios de acesso para conseguir a visualização dos defeitos ósseos no caso de um acometimento de doença periodontal, por exemplo. A extensão e morfologia da perda óssea alveolar podem ser acessadas e examinadas após confecção de retalhos mucoperiosteais em cirurgias periodontais ou através de exames radiográficos. A partir de então, a tecnologia da micro- CT tornou-se padrão ouro para avaliação da arquitetura 3D do osso trabecular; exibindo como uma de suas principais vantagens sua habilidade em proporcionar resultados quantitativos com pouco ou nenhum preparo da amostra e sem a sua destruição. Metodologia: Foram utilizados 40 ratos machos: ratos normotensos (WK) e espontaneamente hipertensos (SHR) foram divididos em grupos com doença periodontal induzida por ligaduras (DP), e grupos controle, em que a DP não foi induzida (C). Cada um desses quatro grupos foram divididos em 2 subgrupos, de acordo com o período de eutanásia, que foi realizada no 10° e no 21° dia do experimento, desse modo cada grupo teve um n=5. Os animais do grupo DP receberam ligadura com fio de algodão ao redor do primeiro molar inferior. Após a eutanásia todas as hemimandíbulas dos animais tiveram seu tecido mole removido através de processos químico e biológico a fim de proporcionar uma peça histológica preparada adequadamente para ser escaneada no microtomógrafo. Para realização da análise microtomográfica foi utilizado um aparelho modelo 1172 da fabricante SkyScan®. As amostras foram verificadas nos três planos espaciais através dos softwares CTAN®, DATA VIEWER® e CTVOX® que também foram utilizados para a visualização tridimensional, análise qualitativa e quantitativa da anatomia externa e interna do osso alveolar. Resultados: Os resultados das medidas lineares foram aqueles extraídos de uma imagem bidimensional de uma fatia única escolhida por ser a mais representativa para detectar a perda óssea alveolar. Para a quantificação dos parâmetros volumétricos foi realizada a avaliação em dois pontos distintos: a área da região de furca do M1 mandibular e a área da região interproximal entre M1 e M2 da mandíbula. De todos os parâmetros avaliados e analisados os mais representativos para detectar a perda óssea alveolar neste modelo de estudo foram: Furca e JCE-COV (junção cemento-esmalte crista óssea vestibular) em 2D (medidas lineares) e a relação entre a superfície óssea e o volume ósseo; relação entre o volume ósseo e o volume total; porosidade e densidade mineral óssea nos parâmetros em 3D (medidas volumétricas). Conclusão: A metodologia empregada mostrou ser eficiente para a caracterização da perda óssea alveolar nos grupos controle e doença periodontal. A região escolhida e o método de análise tem influência no resultado. Assim medidas lineares e medidas volumétricas de uma mesma amostra podem apresentar porcentagens diferentes em relação à perda óssea. / Introduction: The histomorphometry of bone is one of the standard methods that can be used to quantify the microstructure of the trabecular bone. There are many ways to get access to the visualization of bone defects in the case of onset of periodontal disease, for example. The extent and morphology of alveolar bone loss may be accessed and examined after making mucoperiosteais flaps in periodontal or through radiographic examinations surgeries. Since then, the technology of micro - CT has become the gold standard for evaluation of the 3D architecture of trabecular bone; showing as one of its main advantages its ability to provide quantitative results without destruction and with little or no sample preparation. Methodos: Normotensive rats (WK) and spontaneously hypertensive (SHR) were divided into groups of ligature-induced periodontal disease (PD), and control groups (C), where PD is not induced. 40 rats were used and each of these four groups were divided into 2 subgroups according to the time of euthanasia , which was held on the 10th and 21st day of the experiment , thus each group had an n = 5 . The animals in the PD group received ligature with cotton thread around the first molar. After euthanasia, all animals had their mandibles soft tissue removed through chemical and biological processes to provide a suitably prepared for micro-ct analysis. In order to perform the micro-CT analysis, a model 1172 device manufacturer of SkyScan® was used. The samples were observed in the three spatial planes through the CTAN®, DATA VIEWER® and CTVOX® softwares which were also used for threedimensional visualization, qualitative and quantitative analysis of the external and internal anatomy of the alveolar bone. Results: The results of linear measurements were those extracted from a twodimensional image of a single slice chosen for being the most representative for detecting bone loss. For quantification of the volumetric parameters were assessed at two different points: the area of the furcation region of the mandibular M1 and interproximal area of the region between M1 and M2 of the jaw. Of all the most representative in detecting alveolar bone loss in this model of study parameters were evaluated and analyzed : Furcation and cementum-enamel junction to the buccal bone crest = 2D (linear measurements) and the relationship between the bone surface and bone volume ; ratio of bone volume to the total volume ; porosity and bone mineral density in 3D parameters ( volumetric measurements). Conclusion: The methodology was efficient for the characterization of alveolar bone loss in the periodontal disease groups. The region chosen and method of analysis have affected the outcome. Thus, linear and volumetric measurements of the same sample may have different percentages in relation to bone loss.
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Aplicação da microtomografia computadorizada para a análise morfométrica bi e tridimensional na avaliação da perda óssea experimental em ratos / Use of micro-computed tomography in two and three-dimensional morphometric analyses for experimental bone loss evaluation in ratsPatricia Garani Fernandes 04 June 2014 (has links)
Introdução: A histomorfometria do osso é um dos métodos padronizados que pode ser utilizado para quantificar a microestrutura do osso trabecular. Existem muitos meios de acesso para conseguir a visualização dos defeitos ósseos no caso de um acometimento de doença periodontal, por exemplo. A extensão e morfologia da perda óssea alveolar podem ser acessadas e examinadas após confecção de retalhos mucoperiosteais em cirurgias periodontais ou através de exames radiográficos. A partir de então, a tecnologia da micro- CT tornou-se padrão ouro para avaliação da arquitetura 3D do osso trabecular; exibindo como uma de suas principais vantagens sua habilidade em proporcionar resultados quantitativos com pouco ou nenhum preparo da amostra e sem a sua destruição. Metodologia: Foram utilizados 40 ratos machos: ratos normotensos (WK) e espontaneamente hipertensos (SHR) foram divididos em grupos com doença periodontal induzida por ligaduras (DP), e grupos controle, em que a DP não foi induzida (C). Cada um desses quatro grupos foram divididos em 2 subgrupos, de acordo com o período de eutanásia, que foi realizada no 10° e no 21° dia do experimento, desse modo cada grupo teve um n=5. Os animais do grupo DP receberam ligadura com fio de algodão ao redor do primeiro molar inferior. Após a eutanásia todas as hemimandíbulas dos animais tiveram seu tecido mole removido através de processos químico e biológico a fim de proporcionar uma peça histológica preparada adequadamente para ser escaneada no microtomógrafo. Para realização da análise microtomográfica foi utilizado um aparelho modelo 1172 da fabricante SkyScan®. As amostras foram verificadas nos três planos espaciais através dos softwares CTAN®, DATA VIEWER® e CTVOX® que também foram utilizados para a visualização tridimensional, análise qualitativa e quantitativa da anatomia externa e interna do osso alveolar. Resultados: Os resultados das medidas lineares foram aqueles extraídos de uma imagem bidimensional de uma fatia única escolhida por ser a mais representativa para detectar a perda óssea alveolar. Para a quantificação dos parâmetros volumétricos foi realizada a avaliação em dois pontos distintos: a área da região de furca do M1 mandibular e a área da região interproximal entre M1 e M2 da mandíbula. De todos os parâmetros avaliados e analisados os mais representativos para detectar a perda óssea alveolar neste modelo de estudo foram: Furca e JCE-COV (junção cemento-esmalte crista óssea vestibular) em 2D (medidas lineares) e a relação entre a superfície óssea e o volume ósseo; relação entre o volume ósseo e o volume total; porosidade e densidade mineral óssea nos parâmetros em 3D (medidas volumétricas). Conclusão: A metodologia empregada mostrou ser eficiente para a caracterização da perda óssea alveolar nos grupos controle e doença periodontal. A região escolhida e o método de análise tem influência no resultado. Assim medidas lineares e medidas volumétricas de uma mesma amostra podem apresentar porcentagens diferentes em relação à perda óssea. / Introduction: The histomorphometry of bone is one of the standard methods that can be used to quantify the microstructure of the trabecular bone. There are many ways to get access to the visualization of bone defects in the case of onset of periodontal disease, for example. The extent and morphology of alveolar bone loss may be accessed and examined after making mucoperiosteais flaps in periodontal or through radiographic examinations surgeries. Since then, the technology of micro - CT has become the gold standard for evaluation of the 3D architecture of trabecular bone; showing as one of its main advantages its ability to provide quantitative results without destruction and with little or no sample preparation. Methodos: Normotensive rats (WK) and spontaneously hypertensive (SHR) were divided into groups of ligature-induced periodontal disease (PD), and control groups (C), where PD is not induced. 40 rats were used and each of these four groups were divided into 2 subgroups according to the time of euthanasia , which was held on the 10th and 21st day of the experiment , thus each group had an n = 5 . The animals in the PD group received ligature with cotton thread around the first molar. After euthanasia, all animals had their mandibles soft tissue removed through chemical and biological processes to provide a suitably prepared for micro-ct analysis. In order to perform the micro-CT analysis, a model 1172 device manufacturer of SkyScan® was used. The samples were observed in the three spatial planes through the CTAN®, DATA VIEWER® and CTVOX® softwares which were also used for threedimensional visualization, qualitative and quantitative analysis of the external and internal anatomy of the alveolar bone. Results: The results of linear measurements were those extracted from a twodimensional image of a single slice chosen for being the most representative for detecting bone loss. For quantification of the volumetric parameters were assessed at two different points: the area of the furcation region of the mandibular M1 and interproximal area of the region between M1 and M2 of the jaw. Of all the most representative in detecting alveolar bone loss in this model of study parameters were evaluated and analyzed : Furcation and cementum-enamel junction to the buccal bone crest = 2D (linear measurements) and the relationship between the bone surface and bone volume ; ratio of bone volume to the total volume ; porosity and bone mineral density in 3D parameters ( volumetric measurements). Conclusion: The methodology was efficient for the characterization of alveolar bone loss in the periodontal disease groups. The region chosen and method of analysis have affected the outcome. Thus, linear and volumetric measurements of the same sample may have different percentages in relation to bone loss.
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Bi-Lipschitz invariant geometry / Geometria Bi-Lipschitz invarianteSilva, Thiago Filipe da 18 January 2018 (has links)
The study about bi-Lipschitz equisingularity has been a very important subject in Singularity Theory in last decades. Many different approach have cooperated for a better understanding about. One can see that the bi-Lipschitz geometry is able to detect large local changes in curvature more accurately than other kinds of equisingularity. The aim of this thesis is to investigate the bi-Lipschitz geometry in an algebraic viewpoint. We define some algebraic tools developing classical properties. From these tools, we obtain algebraic criterions for the bi-Lipschitz equisingularity of some families of analytic varieties. We present a categorical and homological viewpoints of these algebraic structure developed before. Finally, we approach algebraically the bi-Lipschitz equisingularity of a family of Essentially Isolated Determinantal Singularities. / O estudo da equisingularidade bi-Lipschitz tem sido amplamente investigado nas últimas décadas. Diversas abordagens têm contribuído para uma melhor compreensão a respeito. Observa-se que a geometria bi-Lipschitz é capaz de detectar grandes alterações locais de curvatura com maior precisão quando comparada a outros padrões de equisingularidade. O objetivo desta tese é investigar a geometria bi-Lipschitz do ponto de vista algébrico. Definimos algumas estruturas algébricas desenvolvendo algumas propriedades clássicas. A partir de tais estruturas obtemos critérios algébricos para a equisingularidade bi-Lipschitz de algumas classes de famílias de variedades analíticas. Apresentamos uma visão categórica e homológica dos elementos desenvol- vidos. Finalmente abordamos algebricamente a equisingularidade de famílias de Singularidades Determinantais Essencialmente Isoladas.
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Reforma a vapor catal?tica do metano: Otimiza??o da produ??o e seletividade em hidrog?nio por absor??o in situ do CO2 produzidoCes?rio, Moises R?molos 29 April 2013 (has links)
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Previous issue date: 2013-04-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Topics of research related to energy and environment have significantly grown in
recent years, with the need of its own energy as hydrogen. More particularly,
numerous researches have been focused on hydrogen as energy vector. The main
portion of hydrogen is presently obtained by reforming of methane or light
hydrocarbons (steam, oxy, dry or auto reforming). During the methane steam
reforming process the formation of CO2 undesirable (the main contributor to the
greenhouse effect) is observed. Thus, an oxide material (sorbent) can be used to
capture the CO2 generated during the process and simultaneously shifting the
equilibrium of water gas shift towards thermodynamically more favorable production
of pure hydrogen.
The aim of this study is to develop a material with dual function (catalyst/sorbent) in
the reaction of steam reforming of methane. CaO is well known as CO2 sorbent due
to its high efficiency in reactions of carbonation and easy regeneration through
calcination. However the kinetic of carbonation decreases quickly with time and
carbonation/calcination cycles. A calcium aluminate (Ca12Al14O33) should be used to
avoid sintering and increase the stability of CaO sorbents for several cycles. Nickel,
the industrial catalyst choice for steam reforming has been added to the support from
different manners. These bi-functional materials (sorbent/catalyst) in different molar
ratios CaO.Ca12Al14O33 (48:52, 65:35, 75:25, 90:10) were prepared by different
synthesis methodologies, among them, especially the method of microwave assisted
self-combustion. Synthesis, structure and catalytic performances of Ni-
CaO.Ca12Al14O33 synthesized by the novel method (microwave assisted selfcombustion)
proposed in this work has not being reported yet in literature.
The results indicate that CO2 capture time depends both on the CaO excess and on
operating conditions (eg., temperature and H2O/CH4 ratio). To be efficient for CO2
sorption, temperature of steam reforming needs to be lower than 700 ?C. An
optimized percentage corresponding to 75% of CaO and a ratio H2O/CH4 = 1
provides the most promising results since a smaller amount of water avoids
competition between water and CO2 to form carbonate and hydroxide. If this
competition is most effective (H2O/CH4 = 3) and would have a smaller amount of
CaO available for absorption possibly due to the formation of Ca(OH)2. Therefore, the
capture time was higher (16h) for the ratio H2O/CH4 = 1 than H2O/CH4 = 3 (7h) using
as catalyst one prepared by impregnating the support obtained by microwave
assisted self-combustion. Therefore, it was demonstrated that, with these catalysts,
the CO2 sorption on CaO modifies the balance of the water gas-shift reaction.
Consequently, steam reforming of CH4 is optimized, producing pure H2, complete
conversion of methane and negligible concentration of CO2 and CO during the time
of capture even at low temperature (650 ?C). This validates the concept of the
sorption of CO2 together with methane steam reforming / T?picos de pesquisa relacionados ? energia e meio ambiente t?m crescido
significativamente nos ?ltimos anos, com a necessidade de energia pr?pria como o
hidrog?nio. Mais particularmente, in?meras pesquisas t?m sido focadas em
hidrog?nio como vetor energ?tico. A maior parte de hidrog?nio ? atualmente obtida
por reforma do metano ou hidrocarbonetos (vapor, seco, oxi ou auto reforma).
Durante o processo de reforma a vapor do metano, a forma??o de CO2 indesej?vel
(principal contribuinte ao efeito estufa) ? observada. Dessa forma, um material ?xido
(absorbante) pode ser usado para capturar o CO2 gerado durante o processo e ao
mesmo tempo deslocar o equil?brio da rea??o de deslocamento g?s-?gua no sentido
termodin?mico mais favor?vel ? produ??o de hidrog?nio puro.
O objetivo desse estudo consiste em desenvolver um material com dupla
fun??o (catalisador/absorbante) na rea??o de reforma a vapor do metano. CaO ?
bem conhecido como absorbante do CO2 devido ? sua elevada efici?ncia em
rea??es de carbonata??o e f?cil regenera??o por interm?dio da calcina??o. No
entanto, a cin?tica de carbonata??o decresce rapidamente em fun??o do tempo e
ciclos de carbonata??o e calcina??o. Um aluminato de c?lcio (Ca12Al14O33) deve ser
utilizado para evitar a sinteriza??o e aumentar a estabilidade de absorbantes de
CaO durante v?rios ciclos. O n?quel, o catalisador industrial escolhido para a reforma
a vapor do metano foi adicionado ao suporte em diferentes maneiras. Estes
materiais bi-funcionais (absorbante/catalisador) em diferentes raz?es molares
CaO.Ca12Al14O33 (48:52, 65:35, 75:25, 90:10) foram preparados por diferentes
m?todos de s?ntese, dentre eles, com destaque o m?todo de autocombust?o
assistida por microondas (AAM). S?ntese, estrutura e desempenho catal?tico de Ni-
CaO.Ca12Al14O33 sintetizado pelo novo m?todo (autocombust?o assistida por
microondas) proposto neste trabalho n?o t?m sido reportado na literatura.
Os resultados indicam que o tempo de captura de CO2 depende tanto do
excesso de CaO quanto das condi??es de funcionamento (como, por exemplo, a
temperatura e a raz?o H2O/CH4). Para ser eficiente na absor??o de CO2, a
temperatura de reforma a vapor deve ser inferior a 700 ?C. Uma percentagem
otimizada correspondente a 75% de CaO e uma raz?o (H2O/CH4 = 1) fornece os
resultados mais prometedores uma vez que uma menor quantidade de ?gua evita
uma competi??o entre a ?gua e CO2 para a forma??o de carbonato e hidr?xido. Se
esta competi??o for mais efetiva (H2O/CH4 = 3) ter-se-ia uma menor quantidade de
CaO dispon?vel para absor??o possivelmente devido ? forma??o de Ca(OH)2. Por
isso, o tempo de captura foi maior (16h) para a raz?o H2O/CH4 = 1 do que H2O/CH4 =
3 (7h) usando como catalisador reacional aquele preparado por impregna??o do
suporte obtido por AAM. Portanto, foi demonstrado que, com esses catalisadores, a
absor??o de CO2 por CaO modifica o equil?brio da rea??o de deslocamento g?s?gua.
Consequentemente, a reforma a vapor de CH4 ? otimizada, produzindo
hidrog?nio puro, concentra??es desprez?veis de CO2 e CO durante o tempo de
captura, mesmo a baixa temperatura (650 ? C). Isso confirma o conceito de absor??o
in situ de CO2 durante a reforma a vapor do metano
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A formalização fonético-fonológica da percepção de plosivas surdas sob múltiplas manipulações de voice onset time (VOT) por brasileiros e americanos à luz do modelo "Bhipon"MOTTA-AVILA, Camila 21 December 2017 (has links)
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Previous issue date: 2017-12-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES# / #2075167498588264571# / #600 / This Master’s Dissertation had as its main goal analyzing and formalizing how Brazilian learners of English language (L2) and Americans identify and discriminate the voicing patterns for plosive consonants under artificial manipulation in English monossilabic words. Americans normally follow the acoustic cue Voice Onset Time (VOT) to differentiate voiced plosives from voiceless ones. The VOT is measured in milisseconds and can be classified into three different categories (LISKER & ABRAMSON, 1964): negative VOT (for /b/, /d/ and /g/ in Portuguese); short-lag VOT (for /p/, /t/, /k/ in Portuguese and /b/, /d/, /g/ in English) and long-lag or positive VOT (for [ph], [th], [kh] in English). Previous studies (ALVES, BARATZ e MOTTA, 2012; SCHWARTZHAUPT, ALVES &FONTES, 2015; ALVES & MOTTA, 2014; MOTTA, 2014; ALVES & ZIMMER, 2015) demonstrated that the manipulation of VOT can result into different types of perceptual behaviour, depending on the group analyzed: Americans tend to follow this cue to attribute voicing patterns to consonants, while Brazilians tend to follow the voicing patters stablished for their L1. In order to analyze the perception in L2, this Dissertation was based on Speech Learning Model (SLM) – (FLEGE, 1995) and Perceptual Assimilation Model – L2 (PAM-L2) – (BEST e TYLER, 2007) studies. To investigate how perception was processed in Americans, explanations in Kent and Read (2015), Gussenhoven and Jacobs (2004), Matzenauer (2015) and Boersma, Escudero and Hayes (2003) were found. The method consisted of two perceptual tests: (a) Identification Test, (b) Discrimination Test. Both tests were designed with artificially manipulated stimuli. The types (pee, pit, tick, tip, kit, kill) were CVC (where V was a high vowel /ɪ/ or /i/). Each one of them was multiply manipulated, generating five tokens from one original type. This manipulation was gradually performed, in 25% layers, aiming to achieve the zero artificial VOT pattern. The Identification Test was designed with 60 target words and 12 distractors, resulting in 72 tokens per participant. The Discrimination Test was designed with 36 target trials and 9 catch-trials, in a total of 45 trials per participant. To summarize, results show that Americans can be considered to be more perceptually sensitive to the multiple VOT manipulation than Brazilians, who normally tend to follow their L1 way of attributing voicing patterns to plosives, regardless their proficiency level in English (basic, intermediate or advanced). In addition, different phonetic tresholds were found in each analyzed group and in each place of articulation observed (bilabial, alveolar, velar). Finally, this study tries to offer a formalization for perceptual grammars in each group, based on Bi-directional Phonology OT Model (BiPhon). It is expected that this study, its detailed data description and theoretical observations can contribute to and makefurther academic studies possible. / Esta Dissertação de Mestrado teve como principal objetivo analisar e formalizar de que forma brasileiros aprendizes de inglês (L2) e americanos identificam e discriminam o vozeamento das consoantes plosivas iniciais da língua inglesa sob múltiplas manipulações em palavras monossilábicas. Na língua inglesa, para a diferenciação de vozeamento, tem-se como principal pista acústica a aspiração, que pode ser medida a partir dos valores de Voice Onset Time (VOT). O VOT é medido em milissegundos e pode ser classificado em 3 diferentes padrões (LISKER & ABRAMSON, 1964): VOT NEGATIVO (que se realiza foneticamente em português em /b/, /d/ e /g/); VOT ZERO, (que se realiza como /p/, /t/ e /k/ no português e /b/, /d/ e /g/ no inglês) e o VOT POSITIVO (encontrado em [ph], [th] e [kh] no inglês). Estudos anteriores (ALVES, BARATZ e MOTTA, 2012; SCHWARTZHAUPT, ALVES &FONTES, 2015; ALVES & MOTTA, 2014; MOTTA, 2014; ALVES & ZIMMER, 2015) demonstraram que a manipulação da pista acústica VOT resulta em comportamentos perceptuais diferenciados de acordo com a natureza do participante: americanos tendem a seguir a pista acústica em questão ao atribuir ou não vozeamento para as consoantes plosivas, ao passo que os brasileiros continuam a seguir os padrões de vozeamento previstos para a sua L1. Para dar conta da percepção em inglês como L2, este trabalho fundamentou-se, basicamente, nos modelos perceptuais Speech Learning Model (SLM) – (FLEGE, 1995) e Perceptual Assimilation Model – L2 (PAM-L2) – (BEST e TYLER, 2007). Para analisar a percepção dos participantes americanos, buscaram-se explicações em Kent e Read (2015), Gussenhoven e Jacobs (2004), Matzenauer (2015) e Boersma, Escudero e Hayes (2003). O método aplicado neste estudo consistiu em dois testes de percepção: (a) Teste de Identificação, (b) Teste de Discriminação. Ambos foram montados com estímulos de palavras monossilábicas da língua inglesa (CVC), sendo V /ɪ/ ou /i/. Cada type (pee, pit, tick, tip, kit, kill) passou por manipulação múltipla da pista acústica VOT, gerando 5 tokens cada um. Tal manipulação se deu de forma gradual em camadas de 25%, objetivando-se alcançar o padrão de VOT zero artificial. O design do Teste de Identificação contou com 60 palavras-alvo e 12 distratoras, somando um total de 72 tokens por participante. O design do Teste de Discriminação, que teve por objetivo contrastar diferentes camadas de VOT entre si, contou com 36 tríades do tipo AxB e 9 catch-trials, somando 45 tríades por participante. Sucintamente, os resultados apresentados demonstraram que os participantes americanos são mais sensíveis ao corte da pista acústica VOT do que os participantes brasileiros, independentemente do nível de proficiência em língua inglesa (básico, intermediário e avançado). Além disso, limiares fonéticos distintos foram encontrados em cada um dos grupos analisados e em cada ponto de articulação observado (bilabial, alveolar, velar). Finalmente, propôs-se uma formalização da percepção de ambos os grupos para cada consoante analisada baseando-se no Modelo de OT Bidirecional (BiPhon), proposto por Boersma (2009) e Boersma e Hamman (2011). Espera-se, com este estudo, que a descrição detalhada dos dados e a reflexão teórica possam contribuir à Academia e possibilitar estudos futuros.
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Nouvelles réactions radicalaires multicomposants : carbo-arylation, carbo-oximation, carbo-alcénylation d'oléfinesOvadia, Benjamin 19 December 2014 (has links)
L’objectif de ces travaux de thèse a consisté en le développement de nouveaux accepteurs sulfonylés pour l’élaboration de processus multicomposants radicalaires originaux. De nouvelles réactions de carbo-arylation, carbo-oximation et carbo-alcénylation d’oléfines ont ainsi été mises au point. Nous avons, dans un premier temps, étudié la faisabilité de nouvelles réactions de carbo-hétéroarylation basées sur deux modes d’activation des hétérocycles. Cette méthodologie s’est toutefois révélée être un réel défi en raison de la non-complémentarité des polarités du système, entrainant la formation de plusieurs réactions secondaires et des rendements assez faibles.Dans une seconde partie nous avons étudié le diastéréocontrôle lors de réactions de carbo-oximation d’allylsilanes et d’esters chiraux. Lors de ces processus, les produits de carbo-oximation sont obtenus avec de bons niveaux de diastéréocontrôle mais avec des rendements modestes en raison de l’encombrement stérique et de l’apparition de réactions secondaires. La configuration relative des diastéréoisomères majoritaires n’a pas encore pu être établie avec certitude, mais des modèles d’état de transition peuvent toutefois être proposés afin de prédire la stéréochimie la plus favorable.Dans le but de nous affranchir de l’utilisation d’une quantité stoechiométrique de diétain nous avons également développé de nouveaux accepteurs bi-fonctionnels capables d’agir à la fois comme accepteurs de radicaux nucléophiles et comme sources de radicaux électrophiles via l’α-scission du radical alkylsulfonyle généré. Nous avons mis au point une méthode de préparation de ces accepteurs extrêmement simple et efficace permettant l’accès à une large série de composés.Dans une dernière partie nous avons étendu les résultats obtenus lors des réactions de carbo-alcénylation en préparant de nouveaux accepteurs halogénés et sulfonylés très appauvris en électron par la présence de groupements électroattracteurs. Nous avons finalement réalisé un premier test concluant de carbo-alcénylation à partir d’un vinylsulfoxyde permettant d’envisager la réalisation de ces réactions en version énantiosélective à partir de vinylsulfoxydes énantioenrichis. / This thesis consists in the development of new sulfonylated acceptors for the elaboration of original free-radical multicomponent processes. Thereby, we have developed new free-radical carbo-arylation, carbo-oximation and carbo-alkenylation processes onto olefins.We have first studied the feasibility of new free-radical carbo-heteroarylation based on two different way of activation. This process proved to be very challenging due to the mismatch polarity between the different components, leading to the formation of side reactions and therefore relatively poor yield.In a second part, we examined the diastereocontrol arising from carbo-oximation of chiral allylsilanes and allylic esters. Carbo-oximation products are obtained with high level of selectivity, albeit in modest yields, due to steric hindrance and the formation of side-products. The relative configuration of the major diastereoisomer could not be established, but transition state models may be proposed to predict the most favorable stereochemistry. In order to overcome the use of stoechiometric amount of tin, we have developed new bi-functional reagents which can act both as a trap for nucleophilic radicals as well as a source of electrophilic radical via α-scission of generated alkylsulfonyl radicals. We have developed a very simple and efficient method for the preparation of these acceptors allowing an access to a wide range of compounds.In the final part, we extended the results obtained in the carbo-alkenylation reactions by preparing new activated halogenated and sulfonylated acceptors containing electron-withdrawing groups. We finally carried out a successful test on a carbo-alkenylation reaction using a vinylsulfoxide, offering an entry toward the development of such reactions in an enantioselective series starting from enantioenriched vinylsulfoxides.
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Cyclic Hoist Scheduling Problems in Classical and Sustainabl / Ordonnancement cyclique des ressources de transport dans les ateliers de traitement de surface, dans des contextes traditionnel et durableLei, Weidong 08 December 2014 (has links)
Les ateliers de traitement de surface automatisés, qui utilisent des robots de manutention commandés par ordinateur pour le transport de la pièce, ont été largement mis en place dans différents types d'entreprises industrielles, en raison de ses nombreux avantages par rapport à un mode de production manuel, tels que : une plus grande productivité, une meilleure qualité des produits, et l’impact sur les rythmes de travail. Notre recherche porte sur trois types de problèmes d'ordonnancement associés à ces systèmes, appelés Hoist Scheduling Problems, caractérisés par des contraintes de fenêtres de temps de traitement: (I) un problème à une seule ressource de transport où l’objectif est de minimiser le temps de cycle; (II) un problème bi-objectif avec une seule ressource de transport où il faut minimiser le temps de cycle et la consommation de ressources de traitement (et par conséquent le coût de production); et (III) un problème d'ordonnancement cyclique mono-objectif mais multi-robots.En raison de la NP-complétude des problèmes étudiés et de nombreux avantages de les outils de type quantum-inspired evolutionary algorithm (QEA), nous proposons d'abord un QEA hybride comprenant un mécanisme de décodage amélioré et une procédure réparation dédiée pour trouver le meilleur temps de cycle pour le premier problème. Après cela, afin d'améliorer à la fois la performance économique et environnementale qui constituent deux des trois piliers de la stratégie de développement durable de nos jours déployée dans de nombreuses industries, nous formulons un modèle mathématique bi-objectif pour le deuxième problème en utilisant la méthode de l'intervalle interdit. Ensuite, nous proposons un QEA bi-objectif couplé avec une procédure de recherche locale pour minimiser simultanément le temps de cycle et les coûts de production, en générant un ensemble de solutions Pareto-optimales pour ce problème. Quant au troisième problème, nous constatons que la plupart des approches utilisées dans les recherches actuelles, telles que la programmation entière mixte (MIP), peuvent conduire à l’obtention d’une solution non optimale en raison de la prise en compte courante d’une hypothèse limitant l’exploration de l’espace de recherche et relative aux mouvements en charge des robots. Par conséquent, nous proposons une approche de MIP améliorée qui peut garantir l'optimalité des solutions obtenues pour ce problème, en relaxant l'hypothèse mentionnée ci-dessus.Pour chaque problème, une étude expérimentale a été menée sur des cas industriels ainsi que sur des instances générées aléatoirement. Les résultats obtenus montrent que l’efficacité des algorithmes d'ordonnancement proposés, ce qui justifie les choix que nous avons faits. / Automated treatment surface facilities, which employ computer-controlled hoists for part transportation, have been extensively established in various kinds of industrial companies, because of its numerous advantages over manual system, such as higher productivity, better product quality, and reduced labor intensity. Our research investigates three typical hoist scheduling problems with processing time windows in treatment surface facilities, which are: (I) cyclic single-hoist scheduling problem to minimize the cycle time; (II) cyclic single-hoist scheduling problem to minimize the cycle time and processing resource consumption (and consequently production cost); and (III) cyclic multi-hoist scheduling problem to minimize the cycle time.Due to the NP-completeness of the studied problems and numerous advantages of quantum-inspired evolutionary algorithm (QEA), we first propose a hybrid QEA with improved decoding mechanism and repairing procedure to find the best cycle time for the first problem. After that, to enhance with both the economic and environmental performance, which constitute two of the three pillars of the sustainable strategy nowadays deployed in many industries, we formulate a bi-objective mathematical model for the second problem by using the method of prohibited interval. Then we propose a bi-objective QEA with local search procedure to simultaneously minimize the cycle time and production cost, and we find a set of Pareto-optimal solutions for this problem. As for the third problem, we find that most existing approaches, such as mixed integer programming (MIP) approach, may identify a non-optimal solution to be an optimal one due to an assumption related to the loaded hoist moves which is made in many existing researches. Consequently, we propose an improved MIP approach for this problem by relaxing the above-mentioned assumption. Our approach can guarantee the optimality of its obtained solutions.For each problem, experimental study on industrial instances and random instances has been conducted. Computational results demonstrate that the proposed scheduling algorithms are effective and justify the choices we made.
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