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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.
41

High-temperature, high-pressure NMR probe for superconducting magnets

Mullen, Corina P. 13 December 1996 (has links)
A high-temperature, high-pressure autoclave has been adapted for use with a high-field nuclear magnetic resonance spectrometer. The autoclave has an internal pressure range of atmospheric pressure to 1.5 kbar and a temperature range of 273 K to 1900 K. The autoclave is usable in a high field (8 T) magnet with a room temperature, 76.4 mm bore. The autoclave was tested using assorted nuclear species with resonant frequencies ranging from 57 to 70 MHz at pressures ranging from atmospheric pressure to 1220 bar and temperatures ranging from 273 K to 448 K. Previously, the autoclave was used in conjunction with an iron magnet at temperatures to 1900 K and pressures to 1.5 kbar. / Graduation date: 1997
42

NMR studies reveal the kinetics and thermodynamics of hairpin formation /

Olsen, Katherine Anna. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 140-148).
43

Effect of localized structural perturbations on dendrimer structure

Gabriel, Christopher, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 323-332).
44

Application of high-resolution NMR spectroscopy in metabolic studies of the eye

Risa, Øystein January 2004 (has links)
High-resolution NMR spectroscopy has, during the last two decades, had an increasing impact in biological and biochemical research. Rapid advances have led to improvements in sensitivity and dispersion of the spectra and have allowed more detailed assignment and monitoring of endogenous biochemical molecules. One of the latest implementations has been a technique known as high-resolution magic angle spinning (HR-MAS) NMR spectroscopy which has made it possible to obtain high-resolution proton spectra of intact tissue and cells. Simultaneous detection of a large number of metabolites by NMR spectroscopy has been successfully applied to investigate disordered metabolism for a numerous of diseases and toxic processes. The objectives in the present work have been to evaluate different 1H NMR spectroscopy protocols as analytical tools in eye research, and further use these protocols to extract and interpret information on metabolic changes in the eye induced by external pathological stimuli. Special focus has been paid to changes in the lens and the development of cataracts. The 1H NMR spectra of intact lenses and eye tissue extracts in present thesis showed an extensive picture of NMR detectable metabolites. In addition to the detailed analysis of extracts from cornea, lens and aqueous humour, this work has created a basis for implementation and interpretation of HR-MAS 1H NMR spectroscopy on intact lens tissue. Several significant changes in the metabolic content in cornea, aqueous humour, and lens after alkali-burns to the eye were detected and showed how careful 1H NMR spectroscopy analysis of tissue extracts provided new information (quantitative and qualitative) on the metabolic reaction pattern in the anterior eye segment in relation to eye alkali-burn injuries. HR-MAS studies on lenses exposed in vivo to different ultraviolet-B doses did not reveal any dose-response relationship for the metabolic changes. However, significant concentration changes for most of the observed metabolites seven days post exposure demonstrated that closeto- threshold UVB radiation had great impact on the metabolites in the lens. Further time dependency studies of metabolic changes in rat lens after UVB radiation showed that significant changes in metabolite concentrations were subsequent to lens opacity development. Long-term steroid treatment (36 days) seemed to have greater impact on the metabolic changes compared to the UVB-induced changes 24 hours after UVB radiation. Even though no obvious cataract was detected after the combined treatment of steroids and UVB radiation, significant changes were observed for several metabolites. / Paper III is reprinted with kind permission from Elsevier, sciencedirect.com
45

O17 spin-lattice relaxation solid state NMR studies of pure and doped ices

Groves, Ronald William. January 2002 (has links)
Thesis (Ph. D.)--Ohio State University, 2002. / Title from first page of PDF file. Document formatted into pages; contains xx, 128 p.; also contains graphics. Includes abstract and vita. Co-advisors: Charles H. Pennington and James V. Coe, Dept. of Chemistry. Includes bibliographical references (p. 124-128).
46

NMR analysis of bovine tRNA Trp /

Gong, Qingguo. January 2002 (has links)
Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references (leaves 105-123). Also available in electronic version. Access restricted to campus users.
47

NMR structure and preliminary crystallographic studies of small protein B (SmpB) from Aquifex aeolicus

Dong, Gang. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
48

Solid state NMR cross polarization schemes for peptide samples oriented in hydrated phospholipid bilayers

Kim, Hyeongnam. Cross, Timothy A. January 2003 (has links)
Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. Timothy A. Cross, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Mar. 4, 2004). Includes bibliographical references.
49

NMR spectroscopic and kinetic studies on acyclic and homocyclic enols /

Guo, Bozhang. January 1988 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1988.
50

Determination of C=N bond isomerisation mechanisms in 2, 6-dimethyl-4-aryliminopyrans and their salts by VTNMR using complete line-shape analysis /

Tam, Kwong-chuk, Stephen. January 1988 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1988.

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