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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

Methods of growing crystals from aqueous solution and nuclear magnetic resonance

Holuj, Frank 05 1900 (has links)
Large single crystals, as nearly perfect as possible, are required for magnetic resonance studies of the solid state. A limited number of substances occur naturally in crystals of sufficient size or purity for this type of experiment. Most of the nuclear magnetic resonance work done to date on single crystals has been performed using naturally occurring crystals. Section I of this thesis describes methods used to grow suitable crystals artificially, thus extending the scope of the magnetic resonance experiments. The orthorhombic sodium dihydrogen orthophosphate dehydrate has been produced in large single crystals which were used subsequently in the study of the nuclear magnetic resonance absorption spectrum of Na-23 in this crystal. The spectrum was observed as the crystal was rotated about the three crystallographic axes which are mutually perpendicular for the orthorhombic case. A maximum of twelve lines were observed when neither of the crystallographic axes were perpendicular to the external magnetic field. The number of lines was reduced to six when one of the axes was made perpendicular to the field, while only three lines were observed when two crystallographic axes were made perpendicular to the external magnetic field. These observed numbers of lines were interpreted by assuming four Na-23 sites, possessing identical eigenvalues and differing only in their orientation. These four sites are related by three mutually perpendicular two-fold rotation axes, each of which must be parallel to one of the three crystallographic axes. This interpretation is in complete accord with the space group P222 assigned to NaH2PO42H2O from morphological data. The complete set of properties of the quadruple coupling tensor was determined at each of the Na-23 sites. The value of the quadruple coupling constant (eQ Φzz)/h where Q is the nuclear quadruple moment and Φzz is the largest principle value of the electric field gradient tensor is: 1179.0 ± 0.5 kc/sec. The value of the asymmetry parameter η defined as (Φxx – Φyy)/Φzz is: 0.466 ± 0.005. The table of the direction cosines of the principle axes of the electric field gradient tensor with respect to the crystallographic axes appear in Table VII. / Thesis / Master of Science (MSc)
92

Nuclear Magnetic Resonance Spectra of Some 1,2,4-triazoles

Creagh, Linda Truitt 01 1900 (has links)
In the work undertaken here, NMR has been used to ascertain the structure of some 1,2,4-triazoles. The investigation provides information concerning the structure of potentially tautomeric triazoles such as hydroxy- and aminotriazole. Connected with this aspect of triazole chemistry is the larger problem of mesohydric tautomerism. The present study also yields information for a comparison of substituent effects in triazoles, N-heteroaromatic substances and benzene.
93

Investigations of RNA pseudoknot structures and dynamics by nuclear magnetic resonance spectroscopy /

Wang, Yue, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 126-139). Available also in a digital version from Dissertation Abstracts.
94

The development of laboratory sessions for a introductory course in nuclear magnetic resonance spectroscopy /

Iannaccone, Gennaro A., January 1991 (has links)
Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1991. / Vita. Abstract. Includes bibliographical references. Also available via the Internet.
95

Multi-acquisition and multi-dimensional Earth's field nuclear magnetic resonance spectroscopy : a thesis submitted to the Victoria University of Wellington in fulfilment of the requirements for the degree of Doctor of Philosophy in Physics /

Halse, Meghan Eileen. January 2009 (has links)
Thesis (Ph.D.)--Victoria University of Wellington, 2009. / Includes bibliographical references.
96

Development of new approaches to NMR data collection for protein structure determination

Coggins, Brian E., January 2007 (has links) (PDF)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.
97

Development of new approaches to NMR data collection for protein structure determination

Coggins, Brian E., January 2007 (has links)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.
98

Balanced multi-resonant transmission line nuclear magnetic resonance probes /

Hu, Jianping. January 2010 (has links)
Thesis (Ph. D.)--Brandeis University, 2010. / "UMI:3390495." MICROFILM COPY ALSO AVAILABLE IN THE UNIVERSITY ARCHIVES. Includes bibliographical references.
99

Chemical applications of magnetic resonance

Brown, F. F. January 1970 (has links)
No description available.
100

The construction and operation of a nuclear magnetic resonance probe

Prevo, Charles Telman. January 1962 (has links)
LD2668 .T4 1962 P74

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