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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

Contribution à l'étude, au développement et à la réalisation d'oscillateurs à contrôle numérique en technologie silicium avancée

Seller, Nicolas Bégueret, Jean-Baptiste. January 2008 (has links) (PDF)
Thèse de doctorat : Sciences physiques et de l'ingénieur. Electronique : Bordeaux 1 : 2008. / Titre provenant de l'écran-titre.
92

Une croisière dans les réseaux des réseaux d'accès sans fil aux réseaux de coeur tout optique /

Bouabdallah, Nizar. January 2009 (has links)
Habilitation à diriger des recherches : Informatique et Télécommunications : Rennes 1 : 2009. / Bibliogr. p. 97-103.
93

Etude numérique et expérimentale du thermoformage d'une plaque de verre

Soudre, Laëtitia Jeandel, Gérard. Meshaka, Yves Asllanaj, Fatmir. January 2008 (has links) (PDF)
Thèse de doctorat : Mécanique et Energétique : Nancy 1 : 2008. / Titre provenant de l'écran-titre.
94

Psychodynamique de l'errance traumatisme, fantasmes originaires et mécanismes de périphérisation topique /

Colin, Valérie. Duez, Bernard January 2002 (has links)
Reproduction de : Thèse de doctorat : Psychologie : Lyon 2 : 2002. / Thèse : 2002LYO20006. Titre provenant de l'écran-titre. Bibliogr. Index.
95

Solution Behaviour of Polyethylene Oxide, Nonionic Gemini Surfactants

FitzGerald, Paul Anthony January 2002 (has links)
In recent years there has been increasing interest in novel forms of surfactants. Of particular interest are gemini surfactants, which consist of two conventional surfactants joined by a spacer at the head groups, as they exhibit lower critical micelle concentrations than can be achieved by conventional surfactants. In this work, the self-assembly behaviour of several nonionic gemini surfactants with polyethylene oxide head groups (GemnEm, where n (= 20) is the number of carbons per tail and m (= 10, 15, 20 and 30) is the number of ethylene oxides per head group) were investigated. The Critical Micelle Concentrations (CMCs) were measured using a fluorescence probe technique. The CMCs are all ~2 x 10?7 M, with almost no variation with m. The CMCs are several orders of magnitude lower than conventional C12Em nonionic surfactants. The mixing behaviour of the gemini surfactants with conventional surfactants was also studied. They obeyed ideal mixing behaviour with both ionic and nonionic surfactants. Micelle morphologies were studied using Small Angle Neutron Scattering. The gemini surfactants with the larger head groups (i.e. Gem20E20 and Gem20E30) formed spherical micelles. Gem20E15 showed strong scattering at low Q, characteristic of elongated micelles. As the temperature was increased towards the cloud point, the scattering approached the Q-1 dependence predicted for infinite, straight rods. The existence of anisotropic micelles was supported by the viscosity of Gem20E15, which increases by several orders of magnitude on heating towards its cloud point. Phase behaviour was determined using Diffusive Interfacial Transport coupled to near-infrared spectroscopy. Much of the behaviour of these systems is similar to conventional nonionic surfactants. For example, Gem20E10 forms a dilute liquid isotropic phase (W) coexisting with a concentrated lamellar phase (La) at around room temperature and forms a sponge phase at higher temperatures. This is similar to the behaviour of C12E3 and C12E4. The other surfactants studied are all quite soluble in water and form liquid isotropic and hexagonal phases from room temperature. At higher concentrations Gem20E15 formed a cubic and then a lamellar phase while Gem20E20 formed a cubic phase and then an intermediate phase. This is also comparable to the phase behaviour of conventional nonionic surfactants except the intermediate phase, which is often only observed for surfactant systems with long alkyl tails.
96

Planification stratégique d'un organisme sans but lucratif (O.S.B.L.) /

Leclerc, Alain, January 1988 (has links)
Mémoire (M.P.M.O.)--Université du Québec à Chicoutimi, 1988. / Document électronique également accessible en format PDF. CaQCU
97

L'apprentissage de l'association, 1850-1914 : naissance du secteur volontaire non lucratif dans l'arrondissement de Villefranche-sur-Saône /

Grange, Annie. Agulhon, Maurice, January 1993 (has links)
Texte remanié de: Th. doct.--Hist.--Lyon 2, 1991. Titre de soutenance : Le phénomène associatif, 1850-1914, Associations et groupements divers sans but lucratif dans l'arrondissement de Villefranche-sur-Saône. / Bibliogr. p. 135-139.
98

Une grande loi de la Troisième République, la loi du 1er juillet 1901 /

Merlet, Jean-François. January 2001 (has links)
Texte remanié de: Th. doct.--Droit public--Paris 2, 2000. / En appendice, choix de documents. Bibliogr. p. 655-705. Index.
99

Contribution à l'étude de l'amortissement turbulent d'une onde de Langmuir de très grande amplitude, engendrée par un choc hypersonique dans un plasma non-collisionnel.

Amberg, René, January 1900 (has links)
Th. doct. - ing.--Phys. des gaz et des plasmas--Grenoble 1, 1979. N°: 119.
100

Surfatantes fotorreativos para síntese de nanoparticulas

OLIVEIRA, Rodrigo José de 31 January 2012 (has links)
Submitted by Etelvina Domingos (etelvina.domingos@ufpe.br) on 2015-03-10T19:50:04Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Versão final banca com anexo.pdf: 9105887 bytes, checksum: d1247198ce45985bacd2738e197a7f8d (MD5) / Made available in DSpace on 2015-03-10T19:50:04Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Versão final banca com anexo.pdf: 9105887 bytes, checksum: d1247198ce45985bacd2738e197a7f8d (MD5) Previous issue date: 2012 / CNPq CAPES RENAMI Merck-Southampton / Uma nova classe de surfatantes, chamados fotorreativos (PRS) é apresentada aqui. Estes são anfifilos que podem atuar como precursores em reações fotoquímicas para a síntese de nanopartículas metálicas e de óxidos. Nesta tese foram estudados os seguintes PRSs: 2- etilhexanoato de cobalto (II), Co(EH)2; 2-etilhexanoato de bismuto (III), Bi(EH)3; 2- etilhexanoato de ferro (III), Fe(EH)3 e o 2-etilhexanoato de Manganês (II), Mn(EH)2. As micelas invertidas destes PRSs foram estudadas por viscosidade e espalhamento de nêutrons a baixo ângulo, SANS. Foi verificado que, quando dispersos em hidrocarbonetos como o heptano, estes PRSs formam agregados pequenos com números de agregação entre 3 e 7. Da mesma forma, micelas invertidas mistas de PRS e aerosol-OT (AOT) foram estudadas por viscosimetria, condutividade e SANS. A adição do PRS no sistema misto em heptano não levou a consideráveis mudanças na estrutura micelar, mas em ciclohexano há um aumento na curvatura das micelas, fato atribuído à baixa penetração das moléculas do solvente no filme interfacial e ao efeito de blindagem das repulsões eletrostáticas entre os grupos polares. O efeito da quantidade de PRS em relação a AOT foi estudado por SANS, e observou-se que o aumento da curvatura está diretamente ligada à valência do contra-íon do PRS. Nestes sistemas, a excitação da banda de transferência de carga metal-ligante, LMCT, leva a uma transferência de elétrons do PRS para seu respectivo contra-íon, promovendo a geração de nanopartículas metálicas e de óxidos metálicos nas micelas invertidas. Neste trabalho, é apresentada a prova do conceito do uso de PRS como precursor na síntese fotoquímica de nanopartículas inorgânicas aproximadamente monodispersas. Foram obtidas nanopartículas de Co3O4 e Bi em altas concentrações (10-2 M) pela irradiação das micelas invertidas com luz UV sem a presença de agentes redox ou outras moléculas. O método também se mostrou eficaz para a síntese de óxido de ferro, óxido de cério e óxido de manganês. Estes resultados demonstram que estes sistemas são uma nova abordagem na síntese de nanomateriais em sistemas auto-ordenados fotossensíveis, representando uma rota limpa, direta e simples para síntese de materiais.

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