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Étude, modélisation et conception d'un système de détection de défauts d'arcs électriques pour l'habitat / study, modeling and development of an arcing fault detection system for homeLezama Calvo, Jinmi Gregory 10 December 2014 (has links)
Les défauts d’arcs électriques sont souvent la cause du déclenchement d’un incendie dans l’habitat. Les détecter constitue une amélioration de la sécurité électrique domestique. La contribution de cette thèse porte sur la problématique de l’identification et de la détection de défauts d’arcs électriques sur le réseau basse tension domestique (charge simple et combinée). Dans ce travail de thèse, le premier axe de recherche porte sur la mise en œuvre d’un modèle de simulation de réseau. Sur le modèle de réseau l’objectif est d’introduire à volonté et de manière graphique des charges de nature différentes associées à un défaut d’arc électrique série. La modélisation porte sur la source de tension, des charges domestiques, le défaut d’arc et le bloc d’analyse numérique du courant et de la tension pour la commande d’un disjoncteur. Le second axe de recherche porte la mise au point de méthodes de détection robuste d’un défaut d’arc électrique Quatre méthodes originales de détection portant sur la tension et le courant de ligne ont été développées dans le cadre de ce travail de thèse. Elles sont toutes basées sur l’analyse des caractéristiques fréquentielles et temporelles du courant de ligne. Toutes les méthodes produisent une information dont l’amplitude tend à s’accroître en présence d’un arc électrique. Toutefois, le caractère non déterministe et très variable des signaux produits par un arc électrique ainsi que la grande variabilité des charges et des perturbations qu’elles introduisent rendent la détection très difficile. L’ensemble des études s’est donc systématiquement composé d’une comparaison entre la situation avec et sans arcs. Le résultat a abouti à une approche combinée de plusieurs méthodes et d’un modèle simple de décision basé sur un simple seuil. Un prototype implémentant une partie de l’algorithme a montré la faisabilité d’un circuit en temps réel / The electrical arc faults are the cause of electrical home fire. Detecting them is an improvement of domestic electrical safety. The thesis contribution focuses on the problem of the electrical arc fault identification and detection in the domestic low voltage network. In this thesis, the first research objective is the modeling of a domestic electrical network. The aim of the modeling is to recreate graphically the loads and the topology of the real domestic electrical network associated with a series electrical arc fault. The modeling is made on the AC voltage source, domestic loads, arc fault model and a block of current and voltage analysis to control a circuit breaker. The second research objective is the development of a robust method for detecting arcing fault. Four detecting methods were developed as part of this thesis; they are based on the current analysis of frequency and time characteristics. All methods generate information whose amplitude tends to increase in the presence of an electric arc. However, the non-deterministic and random feature of the signals produced by the electrical arc fault as well as the large number and variability of loads and the disturbances which they introduce make the arc detection very difficult. All the studies consistently are composed of a comparison between the normal operation and arc fault signals. The result has resulted in a combined approach of some methodologies and a simple decision model based on a threshold. A prototype which contains a part of the algorithm was shown the feasibility of a circuit in real time
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A influência do Comitê das Bacias Hidrográficas dos rios Piracicaba, Capivari e Jundiaí (CBH-PCJ) na descentralização da gestão hídrica brasileira - avaliação quantitativa da participação da sociedade civil de 1993-2003 / The influence of the Committee of Hydrographic Basins of Piracicaba, Capivari e Jundiaí rivers (CBH-PCJ) on decentralization of brazilian hydric management - quantitative evaluation of participation of civil society between 1993 and 2003Morgado, Alessandra 17 June 2008 (has links)
A bacia hidrográfica que compreende o Comitê das Bacias Hidrográficas dos rios Piracicaba, Capivari e Jundiaí (CBH-PCJ) está localizada numa região estratégica do ponto de vista econômico e político, concentrando 4,5 milhões de habitantes e 8% do Produto Interno Bruto (PIB) nacional, além de ser um pólo de pesquisas que reúne universidades estaduais e institutos de pesquisa. Trata-se de uma região altamente desenvolvida com zonas de adensamento populacional, como a região de Campinas, que tem 1 milhão de habitantes e, conseqüentemente, com alta taxa de degradação ambiental. Ao mesmo tempo, a região apresenta uma disponibilidade hídrica muito baixa, de 385 m3 ha-1ano-1, volume que equivale à disponibilidade de países semi-áridos da África, resultando em conflitos pela água na região. Essas características fazem do CBH-PCJ um colegiado modelo no Estado e no país. Esse trabalho teve por objetivo traçar um histórico do Comitê das Bacias Hidrográficas dos rios Piracicaba, Capivari e Jundiaí (CBH-PCJ), desde sua fundação, ocorrida em 1993, até a renovação da outorga do Sistema Cantareira em agosto de 2004. O CBH-PCJ é um colegiado formado por representantes dos governos estadual e municipal, além da sociedade civil (organizações não-governamentais), que tem por finalidade gerir as questões ligadas aos recursos hídricos no âmbito da bacia. O estudo avaliou quantitativamente a participação da sociedade civil nas reuniões plenárias do comitê ao longo de dez anos (1993-2003), por meio das listas de presença das reuniões ordinárias e extraordinárias, relacionando a participação à pauta da reunião. O resultado contrariou a hipótese inicial de baixa participação da sociedade civil em relação aos outros setores do colegiado, representados por municípios e órgãos estaduais. O índice de participação da sociedade civil nas primeiras cinco gestões do colegiado teve mínimas de 56,4%, mas manteve entre 70% e 80% presença nas reuniões. Foram selecionados para análise os dez primeiros anos de funcionamento do colegiado no âmbito do Estado de São Paulo, o que compreende de 1993 até 2003, sendo que neste período o colegiado atuava no âmbito estadual. O trabalho também relacionou a opinião de três sindicatos rurais da região do CBH-PCJ, integrantes da Câmara Técnica Rural, sobre a participação no colegiado. O setor considera a participação desses sindicatos importante no sentido de garantir a representação dos agricultores e os interesses da classe. Esse setor foi escolhido porque é responsável por parte considerável do consumo de água dos mananciais para fins de irrigação de culturas. / The water basin wich understands the Piracicaba, Capivari and Jundiai rivers and basin Comitee (CBH-PCJ) is located over a strategic region concerning political and economical view. This region concentrates 4,5 milion inhabitants and 8% of brazilian production, besides its a centre where state universities and institutes base their researches. This is highly developed region in São Paulo State with population gathering zones as Campinas and its surroundings whose 1 milion inhabitants cause great environment degradation. This region presents also low hidrical availability (385 m3 ha-1 year-1) that is similiar to some African countries, wich leads to conflict for water use and supply. Such characteristics turn CBH-PCJ into a model for São Paulo and Brazil. This work aims to draw a historical view of Piracicaba, Capivari and Jundiaí Basins Comitee, from its stablishment in 1993 to the reassignment of Cantareira Sistems concession in 2004. CBH-PCJ is formed by State and cities governments and the civil society, and has the purpose of managing problems related to water sources in these above refered rivers. This study evaluated civil society participation in the Comitee PCJ meetings for ten years - from 1993 to 2003 - throughout presence lists relating meeting topics of frequency. The results went agaist the initial hipotesys of low civil participation in relation to the other State and cities representatives. Civil Society participation rates lowerd to a 56,4% in the first mandates, but sustained in average of 70% to 80% of presence in the meettings. The ten first years of works (1993-2003) when the Comitee actions were taken on the State ambit were selected for this analisys.This essay also relates the opinion of three local rural sindicates, integrals of Rural Technical Council. These sindicates participation is considered to be important to assure agricultors participation and matters as they are responsasible for considerable water consumption for irrigation their crops.
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Análise de fluxo de carga eletrônica em modos vibracionais / Analysis of electronic charge flux in vibrational modesTiago Quevedo Teodoro 19 February 2013 (has links)
Diversas metodologias foram desenvolvidas nas últimas décadas para cálculo de propriedades que representassem quantitativamente a distribuição de carga eletrônica de forma mais simplista. A mais básica destas propriedades é chamada de carga atômica. Contudo, não havendo unanimidade quanto à utilização de um formalismo de cálculo de carga para situações abrangentes de estudo, há a necessidade de trabalhos voltados para uma análise comparativa entre as respostas destes formalismos em termos de carga atômica e parâmetros derivados. Assim, fez-se nesta dissertação uma investigação sobre valores de carga atômica e propriedades dinâmicas relacionadas, com importância em estudos sobre movimentos vibracionais em moléculas, como fluxo de carga e fluxo de dipolo, obtidos com os formalismos de cálculo de carga de Mulliken, NPA, CHELPG e QTAIM. Neste trabalho também se avaliou o efeito da escolha do método de cálculo, como Hartree-Fock e métodos que incluem correlação eletrônica (MP2, MP4(SDQ) e CCSD), e do conjunto de funções de base, através de funções como cc-pVDZ, cc-pVTZ e cc-pVQZ, sobre estas propriedades dinâmicas. Os sistemas analisados incluíram moléculas diatômicas e triatômicas lineares (HF, HCl, LiH, NaH, NaCl, LiF, NaF, LiCl, BF, AlF, BeO, MgO, CO, ClF, CO2, CS2, OCS, HCN e HNC) formadas por ligações de caráter variado, desde altamente iônicas até covalentes e incluindo ligações múltiplas. Também foram estudadas moléculas de clorofluorometanos (CH4, CH3Cl, CH3F, CH2Cl2, CH2F2, CH2ClF, CHCl3, CHF3, CHCl2F, CHClF2, CCl2F2, CClF3, CFCl3, CCl4, e CF4) para observação do efeito da troca de substituintes nas propriedades citadas. Pelos resultados obtidos, pode-se afirmar que apenas os formalismos NPA e QTAIM apresentam bom comportamento quanto à convergência em relação ao método de cálculo e/ou tamanho do conjunto de funções de base utilizados no estudo do fluxo de carga. Entretanto, apenas os valores QTAIM são consistentes com certas considerações químicas fundamentais, como fluxos de carga tendendo a zero durante o estiramento de ligações de predominante caráter iônico, em moléculas com estruturas próximas à geometria de equilíbrio. As cargas e seus fluxos obtidos com Mulliken apresentaram alta dependência e problemas de convergência com a escolha da função de base, além de valores incoerentes em alguns sistemas. Por sua vez, CHELPG não se mostrou adequado à aplicação da aproximação finita de dois pontos na obtenção dos valores numéricos de fluxos de carga. A análise da resposta destas propriedades à troca de substituintes em moléculas de clorofluorometanos seguiu destacando positivamente QTAIM em relação aos outros formalismos. Enquanto CHELPG demonstrou oscilações inconsistentes em gráficos destes valores em função do número de átomos de cloro e/ou flúor, NPA e Mulliken se mostraram sensíveis à troca de substituintes, entretanto, os valores de fluxo de carga observados em alguns casos estão em desacordo com a tendência esperada na troca de átomos de hidrogênio por átomos de cloro ou flúor. / Several methodologies were developed in the last few decades in order to obtain a property which could represent quantitatively electronic charge distributions in a simple way. The fundamental quantity in this treatment is called atomic charge. However, as long as there is not an agreement about the most indicated method to determine atomic charges for general systems or responses under study, it is necessary to analyze, comparatively, how these methods behave in given situations and how the values derived from them respond in each case. Hence, an investigation including charges and related quantities as charge flux and atomic dipole flux, which are of interest to vibrational analysis, was done by means of values resulting from four formalisms, that are, Mulliken, NPA, CHELPG and QTAIM. In this study were also evaluated the changes in such dynamic properties when the calculations are done by means of different methods, as Hartree-Fock and methods that include electron correlation (MP2, MP4(SDQ) and CCSD) and, with different basis sets as cc-pVDZ, cc-pVTZ and cc-pVQZ. The systems analyzed were diatomic and linear triatomic molecules (HF, HCl, LiH, NaH, NaCl, LiF, NaF, LiCl, BF, AlF, BeO, MgO, CO, FCl, CO2, CS2, OCS, HCN and HNC) including diverse bonding character, such as highly ionic or covalent bonds along with multiple bonds. Also, charge and charge flux parameters in chlorofluoromethane molecules (CH4, CH3Cl, CH3F, CH2Cl2, CH2F2, CH2ClF, CHCl3, CHF3, CHCl2F, CHClF2, CCl2F2, CClF3, CFCl3, CCl4 and CF4) were studied to analyze the effects in these properties during the exchange of substituent atoms. Considering the data obtained, one can infer that only NPA and QTAIM formalisms result in satisfactory convergence patterns with chosen methods and/or basis set sizes during the determination of charge and charge flux values. However, only QTAIM charge fluxes seem to follow certain chemical considerations, as low values for charge flux in a bond enlargement in systems with a predominant ionic character close to their equilibrium geometry. The Mulliken formalism shows high dependence and convergence issues in basis set size increments, as well as some inconsistent values. On other hand, CHELPG formalism is not suited to the finite approach for numerical derivatives in its two-point version. The study of substituent effects in chlorofluoromethanes reinforces the performance of QTAIM when compared to other formalisms. While CHELPG returned inconsistent oscillations in plots against the number of chlorine/fluorine atoms, NPA and Mulliken exhibited some sensibility with the change of substituent, though the flux values observed in a few cases are in disagreement with the tendencies expected when the hydrogen atoms are switched by chlorine or fluorine atoms.
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Efeito do campo elétrico sobre a eficiência de separação de cargas foto-geradas em isolantes / Electric field effect on the separation efficiency of photo-charges generated inside insulatorsEvora, Antonio Vieira de Miranda 31 May 1989 (has links)
O presente trabalho faz um estudo do efeito do campo elétrico sobre a eficiência de separação de buracos e elétrons gerados, por um pulso de luz, numa camada próxima da superfície de um isolante. Obtém-se a fração de portadores que é retirada da camada superficial, pelo campo elétrico aplicado, e que entra no interior da amostra. Assume-se que o excesso de carga é instantaneamente produzido por um pulso de luz fortemente absorvido, e que os eletrodos são bloqueantes, evitando injeção secundária. A solução analítica exata é obtida para o caso em que os elétrons e buracos são criados aos pares, e estão sujeitos à recombinação do tipo bimolecular. Num segundo caso, considera-se o mecanismo de fotogeração extrínseco, e os buracos livres podem se recombinar indiretamente com elétrons aprisionados e os elétrons livres podem ser capturados por armadilhas profundas. Impondo-se a condição de que os buracos são muito mais móveis que os elétrons, obtêm-se uma solução numérica que é apresentada graficamente / The effect of the electric field on the efficiency of separation of electrons and holes generated by a strongly absorbed light pulse is studied in two cases. The fraction of carriers that enters the electrode and the one that goes into the sample is calculated assuming instantaneous generation. In the first, carriers are created in pairs and bimolecular recombination prevails. In the second, a photo-generation extrinsic mechanism is assumed, in which generated free holes recombine with trapped electrons present at the surface and electrons excited, out of traps may be captured again. In this last case, the mobility of the holes is assumed to be much larger than the one of the electrons. The numerical solution was found and conveniently ploted
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A cobrança pelo uso da água como instrumento de gestão: o caso da Bacia do Alto Jacaré Guaçú - SP / Water use charges as a management tool: the case of Alto Jacaré Guaçu - São PauloRezende, Cláudia da Silva Aguiar 05 April 2001 (has links)
O presente trabalho discute a cobrança pelo uso da água como instrumento de gestão ambiental, abordando os usuários de água para irrigação e geração de energia elétrica a partir da inserção de parâmetros econômicos e ambientais na definição dos valores a serem cobrados, de forma a monitorar a alocação eficiente dos recursos hídricos. A área escolhida para aplicação dos estudos foi a bacia dos ribeirões do Lobo e do Feijão, formadores do rio Jacaré Guaçú/SP. O estudo levanta a demanda hídrica potencial de ambos os usuários de água, contrapondo à disponibilidade hídrica, aos custos médios de investimento, faturamento médio e o benefício líquido produzidos pelo incremento da água. Foram apresentados valores relativos aos identificados possíveis cenários de conflitos por demanda hídrica, em termos de quantidade, os quais a cobrança poderia atuar como instrumento mediador de interesses e de incentivo ao uso racional da água e do solo. Os resultados da discussão indicam que a cobrança deve considerar não só variáveis econômicas mas, sobretudo, variáveis ambientais e sociais da bacia hidrográfica, possibilitando a articulação da cobrança com os demais instrumentos de gestão dos recursos naturais e a participação efetiva da sociedade na consolidação e aplicação dos valores a serem cobrados. / This study discusses water use charges as an environmental management tool, approaching users for irrigation and electricity generation, applying economic and environmental parameters to determine the charges to be applied to promote efficient allocation of the water resources. The study area comprises of the watersheds of the \"Ribeirão do Lobo\" and the \"Ribeirão do Feijão\", which together form the Jacaré Guaçú River. The study determines the potential water demand by the two users, against the availability, average investment costs, average returns and net profits by increased water availability. Values are presented for the conflict scenarios that were identified in terms of quantity, for which charges could serve as a mediation instrument and as an incentive for efficient use of water and soil. As a result of the study it can be said that water charges, rather than only economic variables, should most of all consider environmental and social variables, integrating the water charges with the other natural resource management instruments and effective social participation for the establishment and application of the charges.
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Plasmonique hybride : propriétés optiques de nanostructures Au-TMD, couplage plasmon-exciton / Hybrid plasmonic : optical properties of TMD-Au nanostructures, plasmon-exciton interactionAbid, Ines 24 November 2017 (has links)
Récemment, la famille des dichalcogénures de métaux de transition (TMDs) (MoS2, WS2, MoSe2...) a suscité l'intérêt de nombreuses équipes de recherche en raison de leurs propriétés optiques, électroniques et spintroniques exceptionnelles. Ma thèse est centrée sur l'association de monocouches de TMDs à des nano-structures plasmoniques. Ces dernières apportent une exaltation des propriétés d'absorption, de diffusion et d'émission optiques qui peuvent être mises à profit dans divers domaines d'applications tels que l'opto-électronique, la photo-catalyse ou les capteurs. Dans une première partie je me suis intéressée à l'interaction plasmon-exciton dans des systèmes hybrides constitués de couches de MoSe2 élaborés par dépôt chimique en phase vapeur (CVD) et transférées sur les nanodisques d'or. La résonance plasmon est contrôlée par le diamètre et la séparation entre les nano-disques. Grâce à des mesures de transmission optique et de photoluminescence, et à une analyse détaillée des réponses spectrales basée sur un modèle analytique et des simulations numériques, j'ai mis en évidence un couplage de type Fano entre les plasmons de surface des nanodisques et les transitions excitoniques de MoSe2. J'ai étudié la dépendance de ce couplage en fonction de la taille des disques, du nombre de monocouches de MoSe2 déposées et aussi en fonction de la température. Une analyse quantitative des résultats a été menée en simulant numériquement non seulement le champ local plasmonique mais aussi son couplage avec le moment dipolaire des transitions excitoniques. Pour compléter l'exploration des propriétés optiques du système MoSe2@Au, je me suis intéressée à la diffusion Raman dans des conditions d'excitation résonante et non-résonante de la transition hybride plasmon-exciton. L'idée principale étant que la résonance plasmonique apporte une exaltation de la diffusion Raman par effet SERS (Surface Enhanced Raman Scattering) tandis que les transitions excitoniques contribuent par l'effet Raman résonnant. Cette combinaison des résonances plasmonique et excitonique conduit à un effet SERS résonant. J'ai ainsi pu distinguer les contributions relatives de ces deux résonances, notamment grâce à l'imagerie confocale de la diffusion Raman. J'ai également montré que, dans ces conditions d'excitation résonnante de la transition plasmon-exciton, un phénomène d'hyperthermie a lieu. la modélisation par simulation numérique du champ proche optique et de la diffusion Raman a été utile pour comprendre les principaux facteurs limitatifs de l'exaltation Raman. Ensuite, la couche de MoSe2 a été utilisée comme substrat de nanoparticules d'Au. Les mesures de photoluminescence ont révélé une extinction quasi-totale de l'émission de la photoluminescence. Afin d'expliquer ce phénomène, deux possibilités ont été discutés : (i) le passage de la structure de bande électronique de la couche de TMD d'un semiconducteur à gap direct à indirect à cause de la contrainte imposée par les nanoparticules d'Au (ii) le désordre structural dû au dépôt des nanoparticules d'Au (iii) le transfert des porteurs photo- générés du semiconducteur vers le métal. Grâce aux mesures Raman, et à l'émission radiative des nanoparticules d'Au, j'ai mis en évidence un phénomène de transfert de charges entre le semi conducteur et le métal. Pour compléter les interprétations proposées, j'ai mené une étude comparative avec les propriétés optiques de couche de TMD couvertes \nolinebreak de silice. Ce travail de thèse a été mené au sein du groupe NeO du CEMES et dans le cadre d'une collaboration avec le groupe du Professeur Jun Lou de l'université de Rice à Houston. / Transition metal dichalcogenide materials (TMDs) are increasingly gaining attention, due to their unique optical, spintronic, and electronic properties. These properties result from the ultimate confinement in 2D monolayers of a direct band-gap semiconductor and the lack of inversion symmetry in the crystallographic structure. To control and enhance the optical response of these materials, it is interesting to integrate them with plasmonic nano-resonators. The TMDs/plasmonic hybrid systems have been extensively studied for plasmon-enhanced optical signals, photocatalysis, photodetectors, and solar cells. In this context, this thesis deals with the interaction between TMD monolayers and gold nanostructures. In a first part, an hybrid system composed of CVD grown MoSe2 monolayers transferred on gold nanodisks was studied. Surface plasmon resonance was tuned by controlling the nanodisks size and the inter-disks separation. The optical properties of the nanostructures are probed by means of spatially resolved optical transmission and photoluminescence spectroscopies. Fano-type coupling regime between the surface plasmon of the gold nanodisks and the MoSe2 exciton was evidenced by a quantitative analysis of the optical extinction spectra based on an analytical model. Our interpretations were supported by numerical simulations. The number of MoSe2 monolayer dependence as well as the Temperature dependence of the plasmon-exciton interaction was investigated. Our results were quantatively analysed on the nanometric scale by studying the local electromagnetic near-field and the excitonic transition dipole momentum interaction. Furthermore, the Raman scattering of MoSe2@Au system was carried out. A particular situation was investigated where a resonant interaction between the surface plasmon of nanodisks and A exciton of v occur. The contribution of these two resonances leads to a resonant surface enhanced Raman scattering (SERRS) effect. The Raman Scattering excitation is selected to resonantly excite the Surface Plasmon resonance and MoSe2 excitonic transition simultaneously. The relative contribution of the surface Plasmon and the confined exciton to the resonant Raman scattering signal is pointed out. In this resonant condition, a hyperthermia effect was detected. Numerical simulations of the SERS gain were useful to figure out the main factors affecting the SERS intensity enhancement in MoSe2@Au. In a second part, the TMD monolayer was used as a substrate of Au nanoparticles. Au nanoislands were deposited on mono- and few-layered MoSe2 flakes. Photoluminescence (PL) measurements revealed a net quenching of the MoSe2 photoluminescence. To figure out the origin of this quenching three possibilities were discussed (i) the charge transfer between the TMD monolayer and the Au particles (ii) the direct to indirect gap transition of the TMD electronic band structure caused by the strain induced by the metal deposition (iii) structural disorder imparted by the nanoparticles in the TMD/metal interface. Owing to the Raman scattering measurements and using the radiative emission of the gold nanoparticles, we evidenced a charge transfetrt between the metallic nanostructures and the semiconductor. In order to complement our interpretations a comparative study with respect to optical properties of TMD covered by a silica film was carried out. The present work was held within the NeO group in CEMES, in a frame of a collaboration with the group of thr Pr. Jun Lou from Rice university, Houston.
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Nouvelles architectures moléculaires électrodéficientes et solubles pour les transistors organiques à effet de champ de type n stables à l’air / New soluble molecular electron-acceptor architectures for air-stable n-type organic field effect transistorsGruntz, Guillaume 18 November 2015 (has links)
Un des enjeux principaux de l’électronique organique est le développement de circuits associant des transistors organiques à effet de champ (OFETs) de type p et de type n stables à l’air ainsi que leur fabrication par voie liquide. Si de nombreux matériaux de type p existent, les exemples de matériaux de type n stables sont plus rares. L’objectif de ce travail de thèse a ainsi été de concevoir, de synthétiser, et de caractériser de nouvelles molécules π-conjuguées électrodéficientes solubles afin de les intégrer dans des transistors organiques à effet de champ de type n (OFETs) stables à l’air. Dans ce but, le coeur aromatique d’un pigment reconnu très stable chimiquement, la triphénodioxazine (TPDO), a été fonctionnalisé avec des fonctions solubilisantes et des groupements électroattracteurs pour moduler ses propriétés de solubilité et augmenter son affinité électronique. Les nombreuses variations structurales réalisées ont conduit à une famille complète de dérivés électrodéficients. Les nouveaux composés, caractérisés à l’état liquide et solide, ont été intégrés dans des OFETs et ont démontré, pour la plupart, un transport de charges négatives efficace. Au-delà de la rationalisation des résultats obtenus lors des synthèses, des caractérisations des matériaux et des performances des dispositifs électroniques, un dérivé tétracyané a rempli l'ensemble du cahier des charges initial (solubilité, mobilité de type n, stabilité à l’air), ce qui valide la démarche adoptée. / One the main challenges of organic electronics is the fabrication of electronic circuits combining p-type and n-type organic field effect transistors which can be processed by liquid route and are stable in air. Even though many efficient p-type organic materials have been reported, the examples of n-type analogues are rare. The aim of this PhD research work was therefore to design, synthesize and characterize new soluble and electron-acceptor π-conjugated molecules and determine their ability to transport electrons in organic field effect transistors (OFETs) under air. In this aim, the aromatic core of a well-known stable pigment, the Triphenodioxazine (TPDO), was functionalized with solubilizing groups and electron-withdrawing functions to tune the solubility and to yield a higher electron affinity. The various structural modifications achieved provided a complete family of electro-deficient materials. The new compounds were characterized in liquid and solid state, and then integrated in OFETs. Most of them led to an efficient negative charge carrier transport. Hereafter of the rationalization of the results during synthesis, characterization of new materials and physical characterizations of devices, a tetracyano derivative has fulfilled the initial project specifications in terms of solubility, electron mobility and air stability of the performances
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Tarifas de energia elétrica no Brasil. / Tariffs of electric energy in Brazil.João Francisco de Castro Carção 01 July 2011 (has links)
Este trabalho tem como objetivo principal analisar o desenvolvimento da indústria da energia elétrica brasileira, a formação e composição das tarifas de energia elétrica e suas implicações e reflexos na economia em geral. Nesse sentido foi feito um breve histórico dessa indústria desde o ano de 1.993, que foi o ano em que se migrou de uma regulação de tarifas pelo sistema denominado custo do serviço para o sistema regulatório denominado price cap, ou seja, preços máximos pelo sistema de incentivos. Foi analisada essa linha regulatória que passou basicamente por dois governos sucessivos, com dois mandatos consecutivos. Fernando Henrique Cardoso no período de 1994 a 2003, que traçou as linhas mestras dessa regulação, com um programa de privatizações de empresas geradoras, transmissoras e distribuidoras de energia elétrica, delegando à iniciativa privada a maior parte da responsabilidade desse serviço. Nessa fase foram constituídas diversas agências reguladoras, sendo criada a ANEEL Agência Nacional de Energia Elétrica, com o objetivo de regular e mediar os interesses dos investidores e dos consumidores. Posteriormente, no governo Luis Inácio Lula da Silva, foi dada continuidade à esse tipo de regulação, com algumas modificações, basicamente na área do planejamento indicativo da expansão do sistema elétrico, que havia sido abandonado. Para analisar o comportamento das tarifas de energia elétrica desde o ano de 2005, foram eleitas cinco distribuidoras de energia elétrica representativas da diversidade geográfica brasileira, e comparado o crescimento do IGP-M com o crescimento das tarifas de consumidores típicos. / This dissertation has as main goal the analysis of the Brazilian electrical energy industry development, the formation and composition of electrical energy fees and its implication and reflexes in the economy as general. This way it is made a small historic of this industry since the year of 1993, which was the year that the regulation of fees by the system named custo do serviço migrated to the regulatory system named price cap, in other words, maximum prices by the system of incentives. This regulatory line, which basically went through two governments successively, was analyzed with two consecutive mandates, Fernando Henrique Cardoso during the period from 1994 to 2003, who wrote the main lines of this regulation, with a program of privatization of generation, transmission and distribution companies, delegating to the private initiative the major part of the responsibility of this service. In this phase were constituted many regulatory agencies, being also created the ANEEL - Agência Nacional de Energia Elétrica (Electrical Energy National Agency), with the goal to regulate and mediate the interests of the investors and consumers. Lately, during the government of Luiz Inácio Lula da Silva, it was given continuity to this kind regulation, with some modifications, basically in the area of planning indicating the expansion of the electrical system, which was abandoned. To analyze the behavior of the electrical energy fees since the year of 2005, were chosen five distributors of electrical energy representatives of the Brazilian geographical diversity and it was made the comparison between the growth of the IGP-M and the growth of the typical consumer fees.
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Ziraldo: análise de sua produção gráfica n\'O Pasquim e no Jornal do Brasil (1969-1977) / Ziraldo: analysis of his graphic production in Pasquim and in Jornal do Brasil (1969-1977)Francisco, Luciano Vieira 30 April 2010 (has links)
A monografia recupera o humor gráfico de Ziraldo, artista tão popular, mas, curiosamente, tão pouco estudado, durante a ditadura militar brasileira. A pesquisa se baseou na descrição pré-iconográfica de seus desenhos em dois periódicos cariocas, um a cada período recortado: de junho de 1969 a junho de 1971, nO Pasquim, e de agosto de 1976 a dezembro de 1977, no Jornal do Brasil (JB) para, posteriormente, realizar uma interpretação iconológica dessa produção, cotejando-a ao levantamento bibliográfico dos principais teóricos sobre o Estado autoritário e as censuras política e moral. A relevância do tema emerge quando ponderamos que, mesmo entrincheirados pela censura, os dois jornais representaram diferentes propostas temáticas, estruturas editoriais e gestão administrativa: liberalista e comercial no caso do JB, cogestão participativa e descompromissada nO Pasquim. Observou-se que no caso dO Pasquim, há preponderância de desenhos sem maiores preocupações diretamente políticas, em que Ziraldo recorreu a variações temáticas acerca da sexualidade, crítica dos costumes e expressões idiomáticas. Sem necessariamente representar um vazio no embate com o regime militar, tais alegorias nos dão sinais da restrição imposta naquela ocasião aos motes políticos, em que o senso moral da classe média passou a ser o alvo, e a censura política, o claustro. Posteriormente, no JB, Ziraldo assume uma postura mais ofensiva à perspectiva política, atacando contradições tanto do cenário internacional, quanto da própria conjuntura interna, seus agentes e instrumentos de cerceamento. Nesse sentido, o trabalho de Ziraldo nos serve como tese, ao evidenciar a grande soma de ataques gráficos por ele desferidos ao regime político entre os editoriais do JB, tendo como suporte um periódico sugestivamente inclinado às questões comerciais e empático a algumas direções econômicas e políticas dos militares. Por outro lado, a relação de seus trabalhos com temas políticos foi quase nula durante os anos duros do mais agressivo ato institucional o 5º ; nesse caso, desenhando sobre sexualidade e costumes da classe média, denunciando justamente sua apatia, tendo como suporte um tablóide recordado como o mais resistente representante da imprensa alternativa no País, O Pasquim. / The monograph recovers Ziraldos graphic humor, such a popular artist, but, surprisingly, so little studied, during the Brazilian military dictatorship. The research was based on the iconography description of his drawings in two carioca newspapers, each one to each period: from June 1969 to June 1971 in Pasquim and from August 1976 to December 1977 in Jornal do Brasil (JB) for, later, accomplishing an iconology interpretation of such a production, comparing it to the bibliography of the main theorists in authoritarian state and the politic and moral censorships. The relevance of the theme emerges when we meditated that, even entrenched by censorship, both newspapers represented different proposed thematic, structures editorials and administration: liberal and commercial in the case of JB, co-administration and unworried in Pasquim. It was observed that in the case of the Pasquim, there is preponderance of drawings with no directly political concerns, in which Ziraldo fell back upon thematic variations concerning sexuality, critic of habits and idiomatic expressions. Without necessarily representing an emptiness in the collision with military dictatorship, such allegories give us signs of the restriction imposed on that occasion to the political mottos, in which moral sense of the middle class became the objective, and the political censorship the confinement. Later, in JB, Ziraldo assumes a more offensive posture to the political perspective, attacking both the international scenery and the very internal conjuncture contradictions, its agents and restriction instruments. In that sense, Ziraldo\'s work serves us as thesis when evidencing the great sum of graphic attacks he did in relation to the political regime among the editorials of JB, having as support a newspaper suggestively tilted to the commercial subjects, and favorable to some economical and political directions of the military. On the other hand, the relationship of his works with political themes was almost null during the hard years of the most aggressive Institutional Act the 5th ; in that case, drawing on sexuality and habits of the middle class, denouncing justly its apathy, having as support a tabloid remembered as the most resistant representative of the alternative press in the country, O Pasquim.
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Transport de charges dans des couches minces hybrides à base de polymère conjugué et de nanocristaux de semi-conducteurs / Charge transport in hybrid thin films based on conjugated polymers and semiconductor nanocrystalsCouderc, Elsa 01 December 2011 (has links)
Cette thèse a pour but d'étudier le transport de charges pho- togénérées dans des matériaux hybrides composés de polymères π-conjugués et de nanocristaux de semi- conducteurs, conçus pour des applications en opto-électronique. La synthèse chimique permet d'obtenir des nanocristaux de CdSe à l'échelle du gramme ayant une faible polydispersité et des formes contrôlées (sphériques, branchées). Les ligands de surface des nanocristaux de CdSe sont échangés par de petites molécules (pyridine, éthanedithiol, phénylènediamine, butylamine, benzènedithiol) afin d'augmenter leur conductivité. L'échange de ligands modifie les niveaux énergétiques des nanocristaux, comme le montrent des études optiques et électrochimiques. Le poly(3-hexylthiophène) déposé sous forme de couches minces présente différents degrés de couplage intermoléculaire et de désordre énergétique selon la méthode de dépôt et le solvant utilisé. Dans les films hybrides, des mesures de diffraction de rayons X en incidence rasante montrent que la structuration cristalline de la matrice organique est modifiée par la présence des nanocristaux. Les mesures de Temps-de-Vol dans les couches hybrides montrent que les mobilités des trous et des électrons varient avec le contenu en nanocristaux, ainsi qu'avec leur forme et leurs ligands. De faibles fractions de nanocristaux provoquent une amélioration de la mobilité des trous, tandis que de plus grandes fractions la détériorent. Les mobilités électroniques sont soumises à une fraction-seuil, as- similable à un seuil de percolation. La fraction optimale de nanocristaux, du point de vue des mobilités des trous et des électrons, est de 36% en volume pour les nanocristaux sphériques avec les ligands de synthèse. Enfin, les simulations Monte-Carlo des courants transitoires photo-générés, dans un échantillon de poly(3-hexylthiophène) et dans un hybride, montrent d'une part que la distribution énergétique du poly(3-hexylthiophène) domine l'allure des courants simulés et d'autre part que les nanocristaux peuvent être assimilés à des sites difficilement accessibles du réseau cubique. / The aim of this work is the study of photogenerated charge transport in hybrid films composed of π-conjugated polymers and of semiconductor nanocrystals, designed for applications in optoelectronics. Chemical synthesis provides gram-scale samples of CdSe nanocrystals, of low polydispersity and con- trolled shapes (spherical, branched). In order to enhance their conductivity, the surface ligands of CdSe nanocrystals (stearic acid, oleylamine) are exchanged by smaller molecules, namely pyridine, ethanedithiol, phenylenediamine, butylamine and benzenedithiol. Optical and electrochemical studies show that the lig- and exchange modifies the nanocrystals' energy levels. Poly(3-hexylthiophene) thin films exhibit varying degrees of energetical disorder and of intermolecular coupling, depending on the processing method and on the solvent used. In hybrid films, the crystallinity of P3HT, probed by grazing incidence X-ray diffraction, is modified by the presence of nanocrystals. Time-of-Flight measurements of hybrid films show that elec- tron and hole mobilities vary with the content of nanocrystals, with their shape, and with their ligands. Small volume fractions of nanocrystals enhance the hole mobility, and large fractions degrade it. Electron mobilities are percolation-limited: they reach a stable value for a threshold fraction of nanocrystals. The optimal fraction of nanocrystals for electron and hole mobilities is 36 vol% in hybrids made of spherical nanocrystals with their synthesis synthesis ligands. Finally, Monte Carlo simulations of photogenerated current transients in pristine poly(3-hexylthiophene) and in a hybrid sample show on one hand that the energy distribution of poly(3-hexylthiophene) rules the shape of the simulated transients, and on the other hand that nanocrystals can be described as little accessible sites of the hopping lattice.
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