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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.
201

Synthèse, caractérisation et test en déshydrogénation de l'isobutane de catalyseurs Pt-Sn-AlO obtenus par introduction de platine et d'étain lors de la synthèse de l'alumine /

Bettcher, Frank. January 1900 (has links)
Th. univ.--Sci. pétrolières--Paris 6, 1994. / Diplôme délivré en association avec l'Ecole nationale supérieure du pétrole et des moteurs. 1995 d'après la déclaration de dépôt légal. Bibliogr. p. 202-208. Résumé en français et en anglais.
202

The utility of modified cyclodextrin, sol-gel procedure and gas chromatography in lipase-mediated enantioselective catalysis Kinetic Resolution of Secondary Alcohols /

Ghanem, Ashraf. January 2002 (has links)
Tübingen, Univ., Diss., 2002.
203

Untersuchung der Einflussfaktoren auf die Mikrostrukturausbildung beim Gefriergiessen (Freeze-Casting)

Waschkies, Thomas January 2009 (has links)
Zugl.: Karlsruhe, Univ., Diss., 2009 / Hergestellt on demand. - Zusätzliches Online-Angebot unter http://uvka.ubka.uni-karlsruhe.de/shop/isbn/978-3-86644-414-0
204

Sol Taishoff's Television Magazine, 1961-1968 an analysis of the relationship between its editorial opinions and subsequent events in broadcasting.

Wesolowski, James Walter, January 1971 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Typescript. Vita. Description based on print version record. Includes bibliographical references.
205

Funktionalisierte Gelschichten aus Tetraethoxysilan und Alkyltriethoxysilanen

Georgi, Ulrike. Unknown Date (has links) (PDF)
Techn. Diss., 1998--Freiberg (Sachsen).
206

Landverteilung und sozialer Frieden im archaischen Griechenland /

Link, Stefan, January 1991 (has links)
Texte remanié de: Habilitationsschrift--Fachbereich 1--Paderborn--Universität-Gesamthochschule, 1991. / Bibliogr. p. [171]-180. Index.
207

Man and environment in Eastern Timor : a geoecological analysis of the Baucau-Viqueque area as a possible basis for regional planning /

Metzner, Joachim K. January 1977 (has links)
Texte remanié de: Th. Ph. D.--Faculty of geoscience--University of Heidelberg, 1973.
208

Stratification de l'espace urbain à partir d'images satellite pour réaliser un sondage à objectif démographique mise au point et évaluation des méthodes d'analyse des images SPOT et LANDSAT TM en milieu urbain /

Michel, Alain, January 1989 (has links)
Th.--Lett.--Paris--Ecole des hautes études en sciences sociales, 1988.
209

The village that vanished : the roots of erosion in a Tanzanian village /

Loiske, Vesa-Matti. January 1995 (has links)
Th. doct--Human geography--University of Stockholm, 1995. / Bibliogr. p. 149-155.
210

Nanosílicas híbridas : síntese em adesivos base-água

Heck, Cesar André January 2012 (has links)
O desenvolvimento de novos adesivos que utilizem água como solvente é dos desafios da indústria de adesivos. A simples substituição dos solventes orgânicos por água não é viável e os adesivos base-água apresentam um desempenho bastante inferior aos adesivos tradicionais. No presente trabalho, foi realizado o estudo de viabilidade do uso de sílicas híbridas, sintetizadas in situ, em emulsões de poliuretano (PU) através de duas rotas sintéticas: sol-gel e grafting. Na obtenção das sílicas híbridas, foram utilizados os seguintes organosilanos: Trifenilsilano, (3-Cloropropil)trimetoxissilano, (3- Isocianatopropil)trietoxissilano, (3-Ciclopentadienilpropil)trietoxissilano, Feniltrimetoxissilano, 3-Aminopropiltrietoxissilano, (3-Glicidiloxipropil)trimetoxissilano, Fenilsilano, Viniltrimetoxissilano, Triclorooctadecilsilano, Clorodimetilsilano, Octadeciltrimetoxissilano, n- Octiltrietoxissilano, n-Propiltrietoxissilano e Metiltrietoxissilano. Os sistemas polímero/sílica híbrida foram caracterizados quanto à resistência mecânica da adesão obtida, resistência mecânica do filme e morfologia. Os resultados mostraram que a estabilidade da emulsão polimérica é determinante na viabilidade da síntese. Foram obtidos compostos estáveis apenas com os organosilanos Octadeciltrimetoxissilano, n-Octiltrietoxissilano, n-Propiltrietoxissilano e Metiltrietoxissilano. Os resultados também mostraram que a resistência à tração do polímero é favorecida pelo método grafting, enquanto que a adesão é favorecida pelo método sol-gel. A adição de sílicas híbridas aumenta a separação das fases do PU. Os melhores resultados foram obtidos com a adição de 3% de sílica gerada in situ pelo método sol-gel. / The development of a new kind of adhesive using water as a solvent (waterborne) is a challenge for adhesive industry. The simple replacement of organic solvents by water is not feasible and waterborne adhesives have a performance much lower than the traditional ones. In the present study, we performed a study on the use of hybrid silicas, synthesized in situ, in emulsions of polyurethane (PU) through two synthetic routes: sol-gel and grafting. The following organosilanes were employed: Triphenylsilane, (3- Chloropropyl)trimethoxysilane, (3-Isocyanatopropyl)triethoxysilane, (3- Cyclopentadienylpropyl)triethoxysilane, 3-Aminopropyltriethoxysilane, (3- Glycidyloxypropyl)trimethoxysilane, Trimethoxyphenylsilane, Phenylsilane, Vinyltrimethoxysilane, Trichloro(octadecyl)silane, Chlorodimethylsilane, Trimethoxy(octadecyl)silane, n-Octyltriethoxysilane, n-Propyltriethoxysilane and Triethoxymethylsilane. The systems polymer/hybrid silica were characterized in terms of adhesion strength, mechanical strength of the film and the resulting structure. The results showed that the stability of polymer emulsion is decisive in the feasibility of synthesis. Stable compounds were obtained only with Trimethoxy(octadecyl)silane, n-Octyltriethoxysilane, n- Propyltriethoxysilane and Triethoxymethylsilane. The results have shown that the tensile strength of the polymer is favoured by the grafting method while the adhesion is favoured by the sol-gel one. The addition of hybrid silica increases phase separation in PU. The best results were obtained with addition of 3 wt.-% of silica generated in situ by the sol-gel method.

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