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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.
81

Diffusion bonding and embossing of Zr[subscript 46.7]Ti[subscript 8.3]Cu[subscript 7.5]Ni₁₀Be[subscript 27.5] bulk metallic glass forming alloy /

Bothara, Manish G. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 78-80). Also available via the World Wide Web.
82

The determination of hafnium and of zirconium by means of iodate

Stevens, Sue Cassell, January 1939 (has links)
Thesis (Ph. D.)--Columbia University, 1940. / Vita. Bibliography: p. [22].
83

Synthesis and electrical conductivity properties of the zirconium trihalide and niobium tetrahalide linear chain systems

Clemmer, Robert Gordon. January 1977 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 230-236).
84

The synthesis, structure, and magnetic properties of reduced state zirconium halides

Kleppinger, James, January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 210-214).
85

The investigation, development and characterisation of novel zirconium-based tanning agents /

Guthrie-Strachan, Jeffry James. January 2005 (has links)
Thesis (Ph. D. (Chemistry))--Rhodes University, 2006.
86

Laramide exhumation and heating in southeastern Arizona low-temperature thermal history and implications for zircon fission-track systematics /

Riley, Brook Colleen Daun. Cloos, Mark, January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Mark Cloos. Vita. Includes bibliographical references.
87

Subcritical crack growth in zirconium alloys

ANDRADE, ARNALDO H.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:38Z (GMT). No. of bitstreams: 1 12909.pdf: 15702388 bytes, checksum: 34a1745824acf01130e6d4c0ec844f3f (MD5) / Tese (Doutoramento) / IPEN/T / Massachussets Institute of Technology, Cambridge, MA
88

Síntese e caracterização de nanopartículas de ZrO2 por rota hidrotérmica /

Padovini, David Santos Souza. January 2013 (has links)
Orientador: Fenelon Martininho Lima Pontes / Banca: Manoel Lima de Menezes / Banca: Cleocir José Dalmaschio / O Programa de Pós Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi / Resumo: Com o crescimento das aplicações dos nanomateriais, as metodologias de síntese têm se tornado importante para pesquisadores e investidores nesse ramo da ciência. A proposta de síntese rápida, com pouco gasto de energia e com reagentes de fácil acesso é o fator principal para pesquisas com nanopartículas. Neste trabalho foram sintetizadas nanoestruturas de ZrO2 utilizando como precursor o butóxido de zircônio pela rota hidrotérmica. Os materiais obtidos foram caracterizados por DRX, FT-Raman, FT-IR, BET, MEV, MET e TG. Os resultados das caracterizações mostraram que a rota de síntese utilizada foi eficiente na produção de nanoestruturas cristalinas de ZrO2 com morfologias diferentes de acordo com a alteração do pH. As amostras apresentaram grande área superficial, consequentemente, houve a formação de partículas muito pequenas, na ordem de 2 nm. A análise de FT-IR e TG mostraram que há uma pequena quantidade de material residual na superfície do material após o tratamento térmico, demonstrando que a técnica hidrotermal mostrou-se eficiente tanto na cristalinização e crescimento do ZrO2 com na eliminação do material orgânico proveniente da síntese. Os estudos de adsorção bem como os espectros de FT-IR mostraram que a rodamina B adsorve quimicamente sobre a superfície da zircônia através do grupo carbonila e do nitrogênio carregado positivamente / Abstract: With the growth of the applications of nanomaterials, synthesis methodologies have become important for researchers and investors in the science field. The proposed rapid synthesis, with little expenditure of energy and reagents easy access is the main factor for research on nanoparticles. In this study, we synthesized nanostructures using ZrO2 as the the precursor zirconium butoxide by hydrothermal route. The materials were characterized by XRD, FT-Raman, FTIR, BET, SEM, TEM and TG. The results of the characterizations showed that the synthesis route used was efficient in the production of crystalline ZrO2 nanostructures with different morphologies according to the pH change. Samples showed large surface area, therefore, there was the formation if very small particles, on the order of 2nm. Analysis of the FT-IR and TG showed that there is a small amount of residual material on the surface of the material after heat treatment, showing that the hydrothermal technique was effective in both the crystallization and growth of ZrO2 with the elimination of organic matrial from the synthesis. Adsorption studies as well as FT-IR spectra of rhodamine B showed that chemically adsorbed on the surface of the zirconia by the carbonyl group and the positively charged nitrogen / Mestre
89

Síntese e caracterização de nanopartículas de ZrO2 por rota hidrotérmica

Padovini, David Santos Souza [UNESP] 25 October 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-10-25Bitstream added on 2014-06-13T19:39:46Z : No. of bitstreams: 1 padovini_dss_me_bauru.pdf: 2151881 bytes, checksum: dbd269312a10cf8c0927305d92de00a1 (MD5) / Com o crescimento das aplicações dos nanomateriais, as metodologias de síntese têm se tornado importante para pesquisadores e investidores nesse ramo da ciência. A proposta de síntese rápida, com pouco gasto de energia e com reagentes de fácil acesso é o fator principal para pesquisas com nanopartículas. Neste trabalho foram sintetizadas nanoestruturas de ZrO2 utilizando como precursor o butóxido de zircônio pela rota hidrotérmica. Os materiais obtidos foram caracterizados por DRX, FT-Raman, FT-IR, BET, MEV, MET e TG. Os resultados das caracterizações mostraram que a rota de síntese utilizada foi eficiente na produção de nanoestruturas cristalinas de ZrO2 com morfologias diferentes de acordo com a alteração do pH. As amostras apresentaram grande área superficial, consequentemente, houve a formação de partículas muito pequenas, na ordem de 2 nm. A análise de FT-IR e TG mostraram que há uma pequena quantidade de material residual na superfície do material após o tratamento térmico, demonstrando que a técnica hidrotermal mostrou-se eficiente tanto na cristalinização e crescimento do ZrO2 com na eliminação do material orgânico proveniente da síntese. Os estudos de adsorção bem como os espectros de FT-IR mostraram que a rodamina B adsorve quimicamente sobre a superfície da zircônia através do grupo carbonila e do nitrogênio carregado positivamente / With the growth of the applications of nanomaterials, synthesis methodologies have become important for researchers and investors in the science field. The proposed rapid synthesis, with little expenditure of energy and reagents easy access is the main factor for research on nanoparticles. In this study, we synthesized nanostructures using ZrO2 as the the precursor zirconium butoxide by hydrothermal route. The materials were characterized by XRD, FT-Raman, FTIR, BET, SEM, TEM and TG. The results of the characterizations showed that the synthesis route used was efficient in the production of crystalline ZrO2 nanostructures with different morphologies according to the pH change. Samples showed large surface area, therefore, there was the formation if very small particles, on the order of 2nm. Analysis of the FT-IR and TG showed that there is a small amount of residual material on the surface of the material after heat treatment, showing that the hydrothermal technique was effective in both the crystallization and growth of ZrO2 with the elimination of organic matrial from the synthesis. Adsorption studies as well as FT-IR spectra of rhodamine B showed that chemically adsorbed on the surface of the zirconia by the carbonyl group and the positively charged nitrogen
90

Subcritical crack growth in zirconium alloys

ANDRADE, ARNALDO H.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:38Z (GMT). No. of bitstreams: 1 12909.pdf: 15702388 bytes, checksum: 34a1745824acf01130e6d4c0ec844f3f (MD5) / Tese (Doutoramento) / IPEN/T / Massachussets Institute of Technology, Cambridge, MA

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