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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.
151

PGE Anion Production from the Sputtering of Natural Insulating Samples

Krestow, Jennifer S. A. 23 February 2011 (has links)
The goal of this research was to devise a new analytical technique, using Accelerator Mass Spectrometry (AMS), to measure Platinum Group Element (PGE) concentrations to the sup-ppb levels in natural, insulating, samples. The challenges were threefold. First, a method of sputtering an insulating sample to successfully produce a stable beam of anions needed to be devised. Second, a suitable standard of known PGE concentrations had to be found and third, spectral analysis of the beam had to verify any claims of PGE abundance. The first challenge was met by employing a modified high intensity negative ion source flooded with neutral caesium that successfully sputtered insulators to produce a beam of negative ions. The second challenge, that of finding a suitable standard, was fraught with difficulties, as no synthesized standards available were found to be appropriate for this work. As a result, direction is provided for future production of standards by ion implantation. The third challenge, successful spectral analysis, was accomplished using a newly designed gas ionization detector which allowed for resolution of the interfering molecular fragment from the PGE ions. Coupled with the use of the SRIM computer programme, positive identification of all peaks in the spectra of the analyzed samples was accomplished. The success of the first and third challenges lead to the qualitative analyses of geological samples for sub-ppb levels of PGE by AMS. Quantitative analyses await only for the appropriate standards and with those will come a whole new range of research possibilities for measuring sub-ppb levels of PGE in insulating samples by AMS.
152

Flashover prevention on polystyrene high voltage insulators in a vacuum

Benwell, Andrew L., January 2007 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 18, 2008) Includes bibliographical references.
153

Analysis of polychlorinated biphenyls in transformer oil /

Phillips, Lyndal. January 2002 (has links)
Thesis (M.Sc.) (Hons.) -- University of Western Sydney, 2002. / A thesis submitted to the University of Western Sydney in fulfillment of the requirements for admission to the [degree of] Masters of Science (Honours). Bibliography : leaves 156-163.
154

Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices /

Davidson, James D. January 1991 (has links)
Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 82-85). Also available on the World Wide Web.
155

Étude temporelle et fréquentielle du courant de fuite des isolateurs de poste recouverts de glace en vue du développement d'un système de surveillance et de prédiction en temps réel du contournement électrique /

Meghnefi, Fethi, January 2007 (has links)
Thèse (D.Eng.) -- Université du Québec à Chicoutimi, 2007. / La p. de t. porte en outre: Thèse présentée à l'Université du Québec à Chicoutimi comme exigence partielle du doctorat en ingénierie. CaQQUQ Bibliogr.: f. 235-244. Document électronique également accessible en format PDF. CaQQUQ
156

Study of electric discharge and space charge formation phenomena in the air gaps of an ice-covered insulator using an icicle/ice-covered plate electrode system = Étude des processus des décharges électriques et formation de charges d'espace dans les intervalles d'air d'un isolateur recouvert de glace à l'aide d'une configuration d'électrodes glaçon/plaque recouverte de glace /

Yu, Defen, January 2007 (has links)
Thèse (D.Eng.) -- Université du Québec à Chicoutimi, 2007. / La p. de t. porte en outre: Thèse présentée à l'Université du Québec à Chicoutimi comme exigence partielle du doctorat en ingénierie. CaQQUQ Bibliogr.: f. 222-239. Document électronique également accessible en format PDF. CaQQUQ
157

Approche physique du développement de streamers positifs sur une surface de glace = Développement of positive streamers along an ice surface : a physical approach /

Ndiaye, Ibrahima, January 2007 (has links)
Thèse (D.Eng.) -- Université du Québec à Chicoutimi, 2007. / La p. de t. porte en outre: Thèse présentée à l'Université du Québec à Chicoutimi comme exigence partielle du doctorat en ingénierie. CaQQUQ Bibliogr.: f. 222-237. Document électronique également accessible en format PDF. CaQQUQ
158

Contournement en courant continu et alternatif des isolateurs givrés, précontaminés ou propres /

Dallaire, Marc-André. January 1992 (has links)
Mémoire (M.Sc.A.)-- Université du Québec à Chicoutimi, 1992. / Bibliogr.: f. 108-109. Document électronique également accessible en format PDF. CaQCU
159

Correlation of microstructural, magnetic, and transport properties of composite metal-insulator films /

Sankar, Sandrawattie, January 2000 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2000. / Vita. Includes bibliographical references.
160

Finite element simulation of mechanical characterization of composite insulators /

Bansal, Anurag, January 1996 (has links)
Thesis (Ph. D.), Oregon Graduate Institute of Science & Technology, 1996.

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