Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-16T14:13:52Z No. of bitstreams: 1 marceloromero.pdf: 4131276 bytes, checksum: 5c51df26c114acbd229a7c2f89f2de9f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-27T21:56:48Z (GMT) No. of bitstreams: 1 marceloromero.pdf: 4131276 bytes, checksum: 5c51df26c114acbd229a7c2f89f2de9f (MD5) / Made available in DSpace on 2016-06-27T21:56:48Z (GMT). No. of bitstreams: 1 marceloromero.pdf: 4131276 bytes, checksum: 5c51df26c114acbd229a7c2f89f2de9f (MD5) Previous issue date: 2015-09-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Essa tese analisa a série de imagens produzidas por Arnaldo Angeli Filho (1956), o chargista Angeli, sobre o governo Fernando Henrique Cardoso (1994-2002), intitulada FHC: biografia não-autorizada. Objetiva caracterizar a interpretação elaborada pelo artista sobre a prática política do governante por meio da identificação e sistematização das estratégias de enunciação da sua crítica política. Procurou demonstrar que nas charges analisadas prevalece o tom da crítica política irascível, além de mordaz e desconcertante, próprio da tradição imagética conformadora da arte caricatural desde o século XVIII, não obstante a subsunção da produção artística do desenhista à linguagem política do periódico que a veiculou, o jornal Folha de S.Paulo. Assim, concebeu-se a charge como um referente histórico por meio do qual se pode acessar o contexto linguístico que lhe foi correspondente, e cuja análise permite reconhecer as práticas e os conflitos políticos expressos pelos atores históricos que se constituíram como interlocutores do debate político no Brasil ao final do século XX. / This thesis analyzes the series of images produced by Arnaldo Angeli Filho (1956), the cartoonist Angeli, on the government of Fernando Henrique Cardoso (1994-2002), entitled FHC: unauthorized biography. Objectively characterize the interpretation developed by the artist on the ruler's political practice by identifying and systematization of enunciation strategies of their political criticism. He sought to show that the charges analyzed prevails the tone of fractious political criticism, and biting and confusing, own the conformadora imagery tradition of caricature art since the eighteenth century, despite the subsumption of artistic production designer to the political language of the journal that ran , the newspaper Folha de S.Paulo. Thus was conceived the cartoon as a historical reference through which one can access the linguistic context that was his correspondent, whose analysis allows to recognize the practical and political conflicts expressed by the historical actors that formed as interlocutors of the political debate in Brazil at the end of the twentieth century.

Doctorat en Sciences / info:eu-repo/semantics/nonPublished

La photocatalyse se base sur l’excitation d’un semi-conducteur par des photons d’énergie supérieure ou égale à son gap, générant des paires électron-trous. Celles-ci sont très réactives et susceptibles de réagir à l’interface pour réaliser par exemple l’oxydation totale d’un composé organique. Cette méthode peut être appliquée sur des eaux usées pour éliminer totalement les polluants organiques qui y sont présents. Dans la perspective d’une utilisation du soleil comme source de lumière, cette méthode peut s’avérer très économique et écologique pour le traitement de l’eau.L’interaction lumière-semi-conducteur et la dynamique des porteurs de charge sont des processus physico-chimiques primordiaux pour la photocatalyse, et il est nécessaire de bien les comprendre pour maîtriser le procédé et développer des matériaux plus efficaces. La Time Resolved Microwave Conductivity (TRMC) est une technique qui se base sur la réflexion des micro-ondes sur un semi-conducteur excité qui est directement reliée avec le nombre de porteurs de charge photo-générés. Il s’agit d’un moyen de sonder en temps réel la dynamique des porteurs de charge dans les semi-conducteurs.Ce travail s’inscrit dans le cadre du projet ANR PhotoNorm. Il consiste en une étude par TRMC de dioxyde de titane TiO2 utilisé pour la dépollution de l’eau par photocatalyse. Une partie de cette étude concerne la caractérisation des propriétés opto-électroniques des matériaux, pour lesquels la dynamique des porteurs de charge sera comparée à l’activité photocatalytique. L’effet bénéfique en photocatalyse de la déposition de nanoparticules d'or, d'argent ou bimetallique or-cuivre sur des TiO2 commerciaux sera relié à une capture d’électrons libres observée en TRMC. L’effet bénéfique sur la photocatalyse en lumière visible a été relié à une injection d’électrons dans le TiO2 par des nanoparticules de bismuth. L’autre partie de ce travail consiste en une étude plus fondamentale de la dynamique des porteurs de charge dans des TiO2 commerciaux ou synthétisés dans le cadre du projet PhotoNorm. Il y sera montré l’importance de la longueur d’onde et de l’intensité d’excitation du matériau sur le rendement de génération de porteurs de charge. L’importance des effets de surface et de l’environnement seront aussi mis en évidence de plusieurs façons. La première consiste simplement en un traitement chimique de la surface (lavage), qui peut avoir une grande influence à la fois sur la dynamique des porteurs de charge et sur la photocatalyse, sûrement en lien avec la présence d’impuretés de surface. La seconde consiste à imprégner le TiO2 par des colorants organiques présentant une forte absorption en lumière visible. Les mesures de TRMC sur ces systèmes permettent de mettre en évidence l’interaction entre le semi-conducteur et les molécules extérieures adsorbées à sa surface, notamment l’injection d’électrons du colorant excité vers le semi-conducteur, mais aussi des effets de recombinaison accrus. La troisième méthode consiste à modifier l’atmosphère de travail en TRMC. Il y est observé notamment l’importance de l’oxygène sur la dynamique des porteurs de charge, et notamment les effets de captures d’électrons, phénomènes qui entrent en jeu dans le processus de photocatalyse.Au final, la TRMC s’avère être un bon moyen d’étude de la durée de vie des porteurs de charge dans les semi-conducteurs, qui peut permettre de mieux comprendre les processus fondamentaux associés à la photocatalyse. / The photocatalysis is based on the excitation of semiconductor by photons with an energy superior or equal to the gap, generating electron-hole pairs. These are very reactive and able to react at the interface, involving for exemple the total oxidation of an organic compound. This method can be used on wastewater to eliminate the organic pollutants. With a view to use the sun as a light source this method may become an economical and ecological way for the water treatment. Light interaction between light and semiconductor and the charge-carrier dynamics are fundamental processes for photocatalysis and it is necessary to understand them in order to manage with this process and develop more efficient materials. The Time Resolved Microwave Conductivity (TRMC) is a method based on the reflexion of microwaves on an excited semiconductor which is linked to the number of photo-generated charge-carriers. This method allows us to probe in real time the charge-carrier dynamics in semiconductor. This work is included in the ANR Photonorm project. It consists in a TRMC study on titanium dioxyde TiO2 used for water depollution by photocatalysis. One part of this study consists in the characterization of the opto-electronic properties of materials for which the charge-carrier dynamics will be compared with the photocatalytic activity. The beneficial effect of nanoparticles deposition of gold, silver or gold-copper bimetallics on commercial TiO2 will be linked to the observation of free electrons observed by TRMC . The beneficial effect on photocatalysis in visible light was linked to an electron injection in TiO2 by bismuth nanoparticles. The second part of this work consists in a more fundamental study of charge-carrier dynamics on commercial or synthetized for the Photonorm project. I will be shown the importance of excitation wavelength and intensities on charge carrier generation. The importance of surface effect and environment will be emphasized by several ways. The first one just consist in surface treatment which can have a major importance on charge-carrier dynamics and photocatalysis, probably in connection with the presence or not of impurities on the surface. The second way consists in impregnating TiO2 by organic dyes which show a strong visible light absorption. The TRMC measurements highlight the interaction between the adsorbed molecules and the semiconducteur, including the electron injection from the excited dye to the TiO2 but also an increased recombination effect. The third method consist in modified the working atmosphere in TRMC. The major role of oxygen is so observed on charge-carrier dynamics, with an effect of electron capture, involving in photocatalytic mechanism.Finally TRMC proves to be a convenient method for studying charge-carrier dynamics in semiconductors, which allow a better understanding of fundamental processes bound to photocatalysis.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23223号 / 工博第4867号 / 新制||工||1760(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 大北 英生, 教授 辻井 敬亘, 教授 田中 一生 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

The efficiency of photoconversion systems, such as organic photovoltaic (OPV) cells, is largely controlled by a series of fundamental photophysical processes occurring at the interface before carrier collection. A profound understanding of ultrafast interfacial charge transfer (CT), charge separation (CS), and charge recombination (CR) is the key determinant to improving the overall performances of photovoltaic devices. The discussion in this dissertation primarily focuses on the relevant parameters that are involved in photon absorption, exciton separation, carrier transport, carrier recombination and carrier collection in organic photovoltaic devices. A combination of steady-state and femtosecond broadband transient spectroscopies was used to investigate the photoinduced charge carrier dynamics in various donor-acceptor systems. Furthermore, this study was extended to investigate some important factors that influence charge transfer in donor-acceptor systems, such as the morphology, energy band alignment, electronic properties and chemical structure. Interestingly, clear correlations among the steady-state measurements, time-resolved spectroscopy results, grain alignment of the electron transporting layer (ETL), carrier mobility, and device performance are found. In this thesis, we explored the significant impacts of ultrafast charge separation and charge recombination at donor/acceptor (D/A) interfaces on the performance of a conjugated polymer PTB7-Th device with three fullerene acceptors: PC71BM, PC61BM and IC60BA. Time-resolved laser spectroscopy and high-resolution electron microscopy can illustrate the basis for fabricating solar cell devices with improved performances. In addition, we studied the effects of the incorporation of heavy metals into π-conjugated chromophores on electron transfer by monitoring the triplet state lifetime of the oligomer using transient absorption spectroscopy, as understanding the mechanisms controlling intersystem crossing and photoinduced electron transfer dynamics is required to improve the device performance of solar cells. Here, we evaluated the effects of incorporating Pt(II) on intersystem crossing and photoinduced electron transfer by comparing and analyzing the photoexcited dynamics of DPP-Pt(II)(acac) and metal-free DPP with different acceptors such as TCNE, TMPyP, and TPyP.

Cette thèse décrit le développement de trois méthodes de formation de liaison C-P par fonctionnalisation de liaison C-H avec l’utilisation d’aucun métal de transition.Tout d’abord, une méthode de phosphorylation régiosélective a été développée via un procédé séquentiel, constitué d’une activation de la pyridine par l’acide de Lewis BF3 suivie d’une oxydation par la chloranile qui réaromatise le cycle pyridinique. La caractérisation de l’intermédiaire de Meisenheimer par des études RMN à basse température nous a permis de confirmer le mécanisme de la réaction. Ensuite, nous avons développé une voie d’accès directe aux oxydes de benzo[b]phosphole à partir d’oxyde de phosphine secondaire et d’alycne via l’utilisation d’un oxydant organique et d’un organophotocatalyseur. Mis à part la grande étendue de cette méthodologie que nous avons appliquée à de nombreux susbtrats, nous avons effectué de nombreuses études physico-chimiques (RPE, RMN, diffraction des rayons X,…), qui nous a permis de proposer un courant. Ces études nous ont notamment permis de caractériser un complexe à transfert de charge existant entre l’état fondamental de l’organophotocatalyseur et l’oxydant organique qui est à l’origine de l’efficience de ce procédé. Enfin, nous avons développé une méthode de phosphorylation régiosélective et photoinduite d’aniline, ne nécessitant l’ajout d’aucun photocatalyseur. La réaction fonctionnne grâce à la photoexcitation d’un complexe à transfert de charge l’aniline et l’oxydant organique. Des études mécanistiques ont permis de caractériser ce complexe ainsi qu’un intermédiaire de type iminium. / This thesis describes the successful development of three modes of activation for the formation of Carbon–Phosphorus bonds under mild conditions and without the use of transition metals.First, a regioselective phosphorylation of pyridines has been developed via a sequential process consisting of the activation of the pyridine with a Lewis acid (BF3) followed by oxidative aromatization mediated by chloranil. The characterization of the Meisenheimer complex enabled to confirm the proposed reaction mechanism. Next, we developed a straightforward approach for the synthesis of benzo[b]phospholes from the reaction of secondary phosphine oxides and alkynes in the presence of an organic oxidant and eosin Y as a catalyst. Apart from the broad scope of this reaction, extensive mechanistic investigations, including EPR, NMR, steady state photolysis permitted the elucidation of the mechanism of this photoreaction. It has been suggested that the oxidant and the photocatalyst come together to form a ground state charge transfer complex that is the driving force of the photocatalyzed process. Finally, we developed a metal-free photoinduced approach for the phosphorylation of anilines and related structures. The reaction proceeded through the formation of an electron donor acceptor complexes between anilines derivatives (electron donors) and N–ethoxypyridinium (electron acceptor). Scope and limitations of this process are discussed along with detailed mechanistic studies.

Die vorliegende Dissertation beschäftigt sich umfassend mit dem Krankheitsbild der Choanalatresie/-stenose und begleitend auftretenden Fehlbildungen. Schwerpunkt ist das CHARGE-Syndrom als häufig vorkommender Fehlbildungskomplex. 25 Patienten wurden mit der Diagnose Choanalatresie/-stenose am Kinderzentrum des Universitätsklinikums Leipzig AöR von 1997 bis 2007 behandelt. In sechs Fällen trat ein CHARGE-Syndrom auf. Zur retrospektiven Auswertung kamen allgemeine Patienteninformationen, Daten zu Schwangerschaft, Geburt und postnataler Anpassung sowie Therapiemaßnahmen, genetische Untersuchungen und der kindliche Wachstumsverlauf. In 16 Fällen konnten prospektive Angaben ermittelt werden. Es erfolgte eine klinische Untersuchung sowie die Durchführung von Entwicklungstests. Dabei wurden je nach Alter des Kindes die Denver Entwicklungsskalen bzw. der Five to Fifteen-Fragebogen eingesetzt. Ein Elternfragebogen diente der Erfassung soziodemographischer Daten, Informationen bezüglich der kindlichen Entwicklung, auftretender Erkrankungen und Inanspruchnahme ambulanter therapeutischer Maßnahmen sowie der Beurteilung der kindlichen Nasenatmung. Besonderes Interesse galt der Einschätzung der Lebensqualität betroffener Eltern. Zum Einsatz kam das Ulmer Lebensqualitäts-Inventar für Eltern chronisch kranker Kinder. Auf die große Bedeutung der kindlichen Frühförderung und die intensive Unterstützung dieser Familien wird hingewiesen.

The main focus of this thesis is the characterization of the charge transport in CdZnTe radiation detectors and the study of the effect of the detector illumination on charge transport. The transport properties are evaluated using Laser-induced Transient Current Technique and the Monte Carlo simulation is used for fitting the measured current waveforms. The properties of the detector prepared from semi-insulating CdZnTe single crystal with a platinum Schottky contacts were measured in the dark in the unpolarized and polarized state and under the anode and cathode continuous LED above-bandgap illumination.

The efficiency and mechanism of electron- and energy transfer events occurring in both in natural and synthetic donor-acceptor systems depend on their distance, relative orientation, and the nature of the surrounding media. Fundamental knowledge gained from model studies is key in building efficient energy harvesting and optoelectronic devices. Faster charge separation and slower charge recombination in donor-acceptor systems is often sought out. In our continued effort to build donor-acceptor systems using near-IR sensitizers, in the present study, we report ground and excited state charge transfer in newly synthesized, directly linked, tetrads featuring bisdonor (donor = phenothiazine and ferrocene), BF2-chelated azadipyrromethane (azaBODIPY) and C60 entities. The tetrads synthesized using multi-step synthetic procedure revealed strong charge transfer interactions in the ground state involving the donor and azaBODIPY entities. The near-IR emitting azaBODIPY acted as a photosensitizing electron acceptor along with fullerene while the phenothiazine and ferrocene entities acted as electron donors. The triads (bisdonor-azaBODIPY) and tetrads revealed ultrafast photoinduced charge separation leading to D•+-azaBODIPY•–-C60 and D•+-azaBODIPY-C60•– (D = phenothiazine or ferrocene) charge separated states from the femtosecond transient absorption spectral studies in both polar and nonpolar solvent media. The charge separated states populated the triplet excited state of azaBODIPY prior returning to the ground state.

Abstract: Understanding and controlling the ultrafast charge carrier and exciton dynamics at the interface of semiconductor nanocrystals (NCs) offer an excellent opportunity to improve the charge collection and the overall performance of many optoelectronic and energy-based devices. In this dissertation, we study how interfacial engineering of these materials can have a direct influence on controlling the charge transfer and the nonradiative losses in different donor-acceptor systems. The first introductory chapter provides an overview of all the fundamental photophysical processes controlling the interfacial phenomena. Then, the second chapter highlights all the chemicals and synthesis methods employed during this thesis. The subsequent two chapters discuss the detailed experimental studies and observations related to different materials and interfaces. First, it describes how we can dramatically tune the intersystem crossing (ISC) rate, the triplet state lifetime, turn on/off the electron injection at the CdTe-Prophyrin interface via tuning either the quantum dot size or the porphyrin molecular structure. Also, how the intermolecular distances, electronic coupling, and subsequently, the photoinduced charge transfer can be controlled by the interfacial electrostatic interactions at CdTe-Fullerene interfaces. Second, due to the promise that of perovskite NCs holds for improving many solar cell and optoelectronic applications, chapter 3 highlights the tremendous effect that the shape of perovskite nanocrystals has on the rate and the mechanism of charge transfer at the MAPbBr3- TCNE interface. Besides, it demonstrates how the confinement effect brought by changing the dimensionality influence the charge transfer dynamics at the MAPbBr3-BQ interface. Finally, it explains how the effective passivation of the surface defects and the subsequent suppression of the formation of surface nonradiative recombination centers in CsPbCl3 NCs controls the photoluminescence quantum yield and the photodetector performance.