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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Monomeric Organo Aluminum and Gallium Monohydroxides as Precursor for Homo and Hetero Bimetallic Oxides: Synthetic, Reactivity and Structural Investigations Including Gold(I) N heterocyclic Carbene Complexes / Monomere Organo-Aluminium und Gallium Monohydroxide als Vorläufer für homo- und hetero-bimetallische Oxide: Synthese, Reaktivität und Strukturuntersuchungen, einschließlich der Gold(I) N heterozyklischen Carben-Komplexe

Singh, Sanjay 12 January 2006 (has links)
No description available.
92

Emil František Burian. Sebeprezentace, reprezentace a paměť / Emil František Burian. Self-presentation, representation and memory

STŘELBOVÁ, Tereza January 2013 (has links)
This diploma thesis reveals the processes of shaping the image of Emil František Burian, the theater director, composer, journalist and playwright in three key headings. The first heading explains the principles of self-presentation and choice of characteristic means to build its external image in the changing personal attitudes and social development in the 30th - 50 years of 20th century. The second heading shows the coordinates of cultural policy communist regime and monitors the construction of public image representative of official socialist culture. Both headings are mainly based on a detailed analysis of Burian's theater activity, broadcasting activities and articles in professional and social printing. The third heading of qualification work pays attention to creating individual memory of a systematic effort to build a "cult of personality" of E. F. Burian. Interpretation biography and memories of actors, directors, journalists and politicians attempts to profile the professional and private life of this artist.
93

Dissimilar Hetero-Interfaces with Group III-A Nitrides : Material And Device Perspectives

Chandrasekar, Hareesh January 2016 (has links) (PDF)
Group III-A nitrides (GaN, AlN, InN and alloys) are materials of considerable contemporary interest and currently enable a wide variety of optoelectronic and high-power, high-frequency electronic applications. All of these applications utilize device structures that employ a single or multiple hetero-junctions, with material compositions varying across the interface. For example, the workhorse of GaN based electronic devices is the high electron mobility transistor (HEMT) which is usually composed of an AlGaN/GaN hetero-junction, where a two-dimensional electron gas (2DEG) is formed due to differences in polarization between the two layers. In addition to such hetero-junctions in the same material family, formation of hetero-interfaces in nitrides begins right from the epitaxy of the very first layer due to the lack of native substrates for their growth. The consequences of such "dissimilar" hetero-junctions typically manifest as large defect densities at this interface which in turn gives rise to defective films. Additionally, if the substrate is also a semiconductor, the electrical properties at such dissimilar semiconductor-nitride hetero-junctions are particularly important in terms of their influence on the performance of nitride devices. Nevertheless, the large defect densities at such dissimilar 3D-3D semiconductor interfaces, which translate into more trap states, also prevents them from being used as active device layers to say nothing of reliability considerations arising because of these defects. Recently, the advent of 2D materials such as graphene and MoS2 has opened up avenues for Van der Waal’s epitaxy of these layered films with practically any other material. Such defect-free integration enables dissimilar semiconductor hetero-junctions to be used as active device layers with carrier transport across the 2D-3D hetero-interface. This thesis deals with hetero-epitaxial growth platforms for reducing defect densities, and the material and electrical properties of dissimilar hetero-junctions with the group III-A nitride material system.
94

A new rheological polymer based on boron siloxane cross-linked by isocyanate groups

Shmelin, George January 2012 (has links)
The research described in this thesis originated from an idea to develop new body protection for the sport of fencing. The ultimate goal is to develop body armour which would be flexible, wearable, washable, light and breathable, offer protection from injuries and cover the entire body of a sportsman. A new material which exhibits shear thickening behaviour has been specially developed for this purpose in the process of this investigation. The material was designed and synthesised as a soft polymeric system which is flexible, chemically stable and able to increase the value of its modulus of elasticity upon impact at a high strain rate, while remaining in its soft gel-like elastomeric state when low strain rate deformation is applied. The polymeric system that has been developed is based on interpenetrating polymeric networks (IPN) of immiscible polyurethane/urea-ester/ether and poly(boron)n(dimethylsiloxane)m (where on average m ≈ 16 n). In addition, as the polydimethylsilane (PDMS) based polymeric system strongly tends to phase separation, the siloxane polymeric network was chemically cross-linked to the polyurethane polymeric network through polyurethane chemical cross-link-bridges. In order to introduce polyurethane cross-links to a siloxane-based polymeric network, some of the attached methyl groups in the PDMS polymeric backbone were substituted by ε-pentanol groups. The resulting polymeric system combines properties of an alternating copolymer with IPN. The actual substitution of the methyl groups of PDMS into alternating ε-pentanol groups was performed by Grignard reaction of trifunctional chlorosilane monomers, magnesium and 1,5-dibromopentane. Chemical analytical techniques like FT-IR, 13C NMR and 1H NMR spectroscopy were used to reveal the chemical structure of the synthesised polymeric network. The mechanical and dynamical properties of the obtained polymeric system were analysed by dynamic mechanical analysis (DMA). This part of the investigation indicated that the novel polymeric system exhibited shear thickening behaviour, but only at a narrow diapason of deformations (i.e., deformations between 2 to 3 % of the length of the sample). At this limited diapason of deformation an effective increase of the modulus of elasticity from 6 MPa (at lower frequencies, i.e., up to ≤6 Hz of the applied oscillating stress) to 65 MPa (at frequencies between 12.5 to 25 Hz) was obtained. However, no increase in the modulus of elasticity was recorded at deformations below 1.5 % or above 3.5 % of length of the sample at the same frequencies (0 to 25Hz) of the applied oscillating stress.
95

Recombinaison dépendante du spin dans les semiconducteurs nitrures dilués / Spin dependent recombination in dilute nitride semiconductors

Zhao, Fan 07 July 2010 (has links)
Ce travail de thèse est une contribution à l'étude des propriétés de spin dans les semiconducteurs par spectroscopie de photoluminescence et par photoconductivité en vue d’applications possibles dans le domaine de l’électronique du spin.Nous avons analysé les propriétés de spin des électrons de conduction dans les matériaux semiconducteurs nitrures dilués, massif et puits quantiques (GaAsN, GaAsN/GaAs). Nous avons étudié le mécanisme de recombinaison dépendante du spin des électrons de conduction sur les centres paramagnétiques induits par l’introduction d’azote dans GaAs. Nous avons mis en évidence l’effet de « filtrage » de spin des électrons de conduction que ce mécanisme peut induire ; en particulier, nous avons mené des études détaillées en fonction de la concentration d’azote, de la puissance excitatrice, d’un champ magnétique externe et, pour les hétérostructures, de l’épaisseur des puits quantiques. L’origine chimique des centres paramagnétiques a été, de plus, identifiée par des études de résonance paramagnétique détectée optiquement (ODMR).Nous avons également complété ces études purement optiques sur la recombinaison dépendante du spin, par des expériences de photoconductivité en vue d’applications possibles liées à l’électronique du spin. Nous avons montré que la photoconductivité des matériaux nitrures dilués peut être contrôlée par la polarisation de la lumière incidente. Un détecteur électrique de la polarisation de la lumière à base de GaAsN a été ainsi fabriqué et testé.Ces résultats ont été également interprétés et simulés grâce à un système d’équations dynamiques pouvant rendre compte à la fois des résultats de photoluminescence et de transport / This thesis work is a contribution to the investigation of the spin properties of semiconductors by photoluminescence and photoconductivity spectroscopy with the aim of future applications in the spintronic field. We have studied the conduction band electron spin properties of dilute nitride semiconductors in epilayers and quantum wells (GaAsN, GaAsN/GaAs). In particular, we have investigated the spin dependent recombination of conduction band electrons on deep paramagnetic centers induced by the introduction of nitrogen into GaAs. We have also evidenced the “spin filtering” effect made possible by this spin dependent recombination mechanism. More precisely, we have carried out a systematic study of the spin filtering effect as a function of the nitrogen concentration, excitation power, external magnetic field and, for the hetero-structures, as well as a function of the quantum well thickness. The chemical origin of the deep paramagnetic centers has been also determined by optically detected magnetic resonance (ODMR). We have completed these all-optical studies on the spin dependent recombination by photoconductivity experiments in order to demonstrate a “proof of concept” system for spintronic applications. We have shown that the photoconductivity in dilute nitride semiconductors can be controlled by the polarization of the incident light: an electrical detector of the light polarization has therefore been built. These results have been as well modeled thanks to a rate equation system able to reproduced both the photoluminescence and photoconductivity experimental results
96

Resistance bodies on the México-U.S.border : Peripheral feminisms

Lolo García, Montserrat January 2016 (has links)
The present study shows and analyses how bodies codified as women’s bodies can resist in an extreme violence context situated in Ciudad Juárez on the México-U.S. border. To be resistant or to make resistance in these circumstances can be represented in different ways, through social and civic movements, art, literature and weapons. How these women’s bodies seem and how their resistance is and what they represent is the line of investigation of this study. This resistance is a direct confrontation to the feminicide and the diverse forms of violence against bodies codified as women exercised by men. As well as the peripheral feminisms it is a confrontation to a cis hetero-patriarchal capitalist context. Women’s bodies are the territory or the stage where violence, terror, power and exploitation converge. The reaction and rejection to this situation by a diverse collective of women highlights the struggle and the activism that these groups have as a way of life, a way of dissent and finally a way of resistance.
97

Perception du diabète de type 1 auto- et hétéro-évaluée par les adolescents et leurs parents : analyse des liens avec leur qualité de vie, la gestion familiale de la maladie et le contrôle métabolique / Type 1 diabetes’ perception self- and hetero-evaluated by adolescents and their parents : link analysis with their quality of life, family management of the disease, and metabolic control

Terrasson, Johanna 18 January 2019 (has links)
Cette thèse porte sur une population d’adolescents ayant un diabète de type 1 et leurs parents. Elle examine l’influence de la perception du diabète de type 1 par les adolescents et par leurs parents sur leur ajustement respectif à la maladie. En premier lieu sont présentées les caractéristiques du diabète de type 1, ses spécificités à l’adolescence, et les deux critères retenus pour examiner l’ajustement à la maladie : le contrôle métabolique et la qualité de vie. Après avoir défini la notion de perception de la maladie et décrit ses influences sur l’ajustement, le rôle de la perception des proches est examiné. L’étude de la perception de la maladie dans la famille en auto- et en hétéro-évaluation est ensuite proposée. Les deux axes de recherche envisagés visent à mettre en évidence l’existence d’une potentielle interprétation de la perception des proches et à en analyser l’influence sur l’ajustement à la maladie. Les deux premières études mettent en évidence l’impact de la perception du diabète en auto- et en hétéro-évaluation, par les adolescents et leurs parents, sur leur ajustement. La dernière étude permet de rendre compte, par une approche qualitative, des liens entre la perception de la maladie dans la famille et la qualité de vie des adolescents, au regard de la gestion familiale du diabète. En conclusion, nous soutenons l’intérêt de l’étude de la perception de la maladie dans la famille par le prisme de la perception interpersonnelle et de la méta-perception. Les limites de ce travail, les pistes de recherche et les perspectives d’application sont finalement discutées. / This thesis focuses on a population of adolescents with type 1 diabetes and their parents. It examines the influence of adolescents’ and their parents’ perceptions of type 1 diabetes, on their respective adjustments to the disease. First, we present the characteristics of type 1 diabetes, its specificities in adolescence, and two criteria used to examine adjustment to the disease : metabolic control and quality of life. After having defined the notion of illness perception and describing its influences on adjustment, the role of family members' perception is examined. A study of illness perception in the family through self- and hetero-evaluation is then presented. The two lines of research aim to highlight the existence of potential interpretations of the family members’ perceptions and analyze their influence on adjustment to the illness. The first two studies highlight the impact of type 1 diabetes' perception, both self- and hetero-evaluation, by adolescents and their parents on their adjustment. The last study reports, using a qualitative approach, the links between illness perception in the family and adolescents' quality of life, in light of family diabetes management. In conclusion, our studies provide further support the need to study the illness perception in the family through the prism of interpersonal perception and meta-perception. Finally, the limits of this work and research and applied perspectives are discussed.
98

Quels apports de l’approche contextualisée à l'évaluation de l'intelligence chez les adolescent·e·s ? / Which contributions of the contextual approach to the intelligence assessment with adolescents?

Terriot, Katia 18 December 2018 (has links)
L'objectif principal de la thèse est de montrer les apports de l'évaluation contextualisée à l'évaluation de l'intelligence chez les adolescents.e.s, à travers cinq articles. Le premier fait l'état des lieux de l'évaluation contextualisée de l'intelligence. Le second développe les évaluations auto et hétéro-rapportées de l'intelligence. Les trois suivants rendent compte des apports d'outils d'évaluation contextualisée notamment en termes de preuve de validité. Seul le facteur de raisonnement fluide du questionnaire d'auto-évaluation prédit les résultats scolaires. Les liens avec le comportement adaptatif existent, notamment avec le facteur de vitesse de traitement du questionnaire (r=.69). Les questionnaires d'hétéro-évaluations entretiennent des liens modérés à forts avec les résultats scolaires. Enfin, pour le test de performance composé de sept subtests, seule une épreuve (intelligence cristallisée) corrèle positivement et significativement avec la moyenne scolaire générale (r=.42); et trois avec le comportement adaptatif (corrélations néanmoins faibles). Les résultats et implications de ces résultats sont discutés dans la conclusion et une ouverture sur la réalité virtuelle est proposée. / The main objective of the thesis is to show the contributions of the contextualized evaluation to the evaluation of the intelligence of teenagers, through five articles. The first takes stock of the contextualized evaluation of intelligence. The second develops self and hetero-reported assessments of intelligence. The following three report the contributions of contextualized evaluation tests, particularly in terms of proof of validity. Only the fluid reasoning factor of the self-report questionnaire predicts school results. The links with adaptive behavior exist, notably with the processing speed factor of the questionnaire (r = .69). Hetero-assessment questionnaires have moderate to strong links to school performance. Finally, for the performance test composed of seven subtests, only one subtest (crystallized intelligence) correlates positively and significantly with school results (r = .42); and three with adaptive behavior (yet weak correlations). The results and implications of these results are discussed in the conclusion and an opening on virtual reality is proposed.
99

The influence of adsorbed polymer on clay and copper mineral particles' interactions

He, Mingzhao January 2009 (has links)
Attractive particle interactions which lead to the hetero-aggregation or 'sliming' of silicate clay gangue and valuable sulphide mineral particles are encountered in a number of hydrometallurgical and flotation processes. Sliming leads to poor recovery of the valuable minerals and high recovery of the clay gangue minerals in flotation concentrates. In the present work, the hetero-aggregation mechanism of hydrophilic mica clay mineral sericite (or muscovite) and hydrophobic chalcocite was investigated by probing the particle interactions and the prevailing interfacial chemistry under dispersion conditions where the individual chalcocite and sericite particles displayed negative zeta potentials. The mitigation/suppression of the hetero-aggregation was examined via the prudent control of dispersion conditions and pulp chemistry (i.e., pH modification and solution speciation control) and the use of two, anionic, polymeric dispersants with different molecular weight and functionality (carboxylate-substituted polyacrylamide, Cyquest 3223 and sulphonate-substituted polymaleic acid, P80 co-polymers) as dispersants. The adsorption behaviour of both polymers onto both minerals under industrially relevant suspension conditions have been quantified in terms of the polymer adsorption density and the adsorbed layer characteristics. These interfacial layer properties which impact on the mineral particles' zeta potentials and interactions, and also underpin the dispersion efficacy of polymers were characterized, using interfacial and solution analytical methods and TM-AFM imaging analysis.
100

Synthèse de nouveaux dérivés pyrazolo[1,5-a]pyrimidiniques à visée biologique / Synthesis of new pyrazolo[1,5-a]pyrimidinic derivatives aiming at biological activity

Bassoude, Ibtissam 09 July 2012 (has links)
Nos travaux de thèse portent sur la mise au point de nouvelles méthodes de synthèse permettant l’accès de façon rapide et efficace à différents dérivés pyrazolo[1,5-a]pyrimidiniques diversement fonctionnalisés.La première partie de ce travail concerne l’étude et l’application de la condensation de la pyran-2-one avec les 5(3)-amino-3(5)-arylpyrazoles que ce soit par chauffage classique ou sous irradiation micro-onde. Par la suite, un nouveau procédé d’(hétéro)arylation pallado-catalysé direct régiosélectif a été mis à profit pour élaborer des pyrazolo[1,5-a]pyrimidines fonctionnalisées tant en position 3 que sur le méthyle situé sur le sommet 7 de la 5,7-diméthylpyrazolo[1,5-a]pyrimidine.Le dernier volet de ce mémoire a été consacré à la préparation des entités pyrazolo[1,5-a]pyrimidiniques substituées en position 7 par des motifs benzyliques et ce, via une procédure « one-pot », sous irradiation micro-onde, constituée d’une réaction d’arylation directe pallado-catalysée suivie d’une saponification-décarboxylation. / Our thesis works concern the development of new methods of synthesis allowing a rapid and effective access to variously functionalized pyrazolo [1,5-a] pyrimidines derivatives.First, we were explored the study and the application of the condensation of the pyran-2 one with 5(3)-amino-3 (5)-arylpyrazoles whether it is by classic heating or under microwaves. Indeed, we have described the first example of the direct and regioselective palladium-catalyzed (hetero)arylation of 5,7-dimethylpyrazolo[1,5-a]pyrimidine, the reaction may be inducted to occur at either an sp2 or an sp3 carbon atom.The last part of this report was dedicated to the preparation of some 7-substituted pyrazolo[1,5-a]pyrimidines via a one-pot two steps palladium-catalyzed direct CH-arylation followed by a saponification-decarboxylation.

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