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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.
21

Construction and development of a nuclear magnetic resonance detection system

Goodwin, Charles D. 03 June 2011 (has links)
The major work involved is the debugging procedure on the Varian Model V-21003 electromagnet, power supply and spectrometer and the design and construction of supporting structure to house the various pieces of apparatus which were required to complete the system.Equipment which was not immediately available was then designed and constructed, with the final step being the testing. of the entire system for its integrity.Adjustments to each component was then carried out to obtain the best signal possible, noting the various changes caused by the condition and setting of each section of the system.
22

A computer analysis of NMR-determined interatomic distances in steontium formate

Dick, Roger L. 03 June 2011 (has links)
This thesis comprises a computer analysis of NMR-determined interatomic distance in strontium formate dihydrate. The computer program is designed to locate the hydrogen atoms associated with the water molecules in strontium formate dihydrate. The bond length of the oxygen-hydrogen bond is assumed to be fixed. The program varies the hydrogen separation, plotting total proton interaction against the hydrogen separation distance. Using Van Vleck's second moment theory, the hydrogen-hydrogen distances were determined.. The value of the second moment of the NMR absorption curve is 24.6 gauss2, obtained from investigation by Dr. D. E. Koltenbah. The result of this thesis is that the proton separation is 1.47± .02 A. This result is found to be close enough to other studies to conclude that the program analysis is essentially sound.
23

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

Coggins, Brian E. 10 May 2007 (has links)
Multidimensional nuclear magnetic resonance (NMR) spectroscopy has become one of the most important techniques available for studying the structure and function of biological macromolecules at atomic resolution. The conventional approach to multidimensional NMR involves the sampling of the time domain on a Cartesian grid followed by a multidimensional Fourier transform (FT). While this approach yields high quality spectra, as the number of dimensions is increased the time needed for sampling on a Cartesian grid increases exponentially, making it impractical to record 4-D spectra at high resolution and impossible to record 5-D spectra at all. This thesis describes new approaches to data collection and processing that make it possible to obtain spectra at higher resolution and/or with a higher dimensionality than was previously feasible with the conventional method. The central focus of this work has been the sampling of the time domain along radial spokes, which was recently introduced into the NMR community. If each radial spoke is processed by an FT with respect to radius, a set of projections of the higher-dimensional spectrum are obtained. Full spectra at high resolution can be generated from these projections via tomographic reconstruction. We generalized the lower-value reconstruction algorithm from the literature, and later integrated it with the backprojection algorithm in a hybrid reconstruction method. These methods permit the reconstruction of accurate 4-D and 5- D spectra at very high resolution, from only a small number of projections, as we demonstrated in the reconstruction of 4-D and 5-D sequential assignment spectra on small and large proteins. For nuclear Overhauser spectroscopy (NOESY), used to measure interproton distances in proteins, one requires quantitative reconstructions. We have successfully obtained these using filtered backprojection, which we found was equivalent to processing the radially sampled data by a polar FT. All of these methods represent significant gains in data collection efficiency over conventional approaches. The polar FT interpretation suggested that the problem could be analyzed using FT theory, to design even more efficient methods. We have developed a new approach to sampling, using concentric rings of sampling points, which represents a further improvement in efficiency and sensitivity over radial sampling. / Dissertation
24

Force detection of nuclear magnetic resonance using double-torsional micro-oscillators

Chabot, Michelle Diane. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.
25

Ultrafast coherent transients & excited state dynamics in gases and solids

Bromberg, J. Philip, McConnell, Harden M. January 1959 (has links)
Thesis (Masters)--California Institute of Technology, 1959. / Advisor names found in the Acknowledgments pages of the thesis. Title from home page. Viewed 02/09/10. Includes bibliographical references.
26

Structure of the [beta] subunit of translation initiation factor 2 from the Archaeon Methanococcus jannaschii by NMR a representative of the eIF2[beta]/eIF5 family of proteins /

Cho, Seongeun. January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
27

Construction of a low temperature nuclear magnetic resonance force microscope

Lee, Yong J. 28 August 2008 (has links)
Not available / text
28

Force detection of nuclear magnetic resonance using double-torsional micro-oscillators

Chabot, Michelle Diane 25 March 2011 (has links)
Not available / text
29

Design options for nuclear magnetic resonance (NMR) sensors

Jain, Karishma January 2013 (has links)
No description available.
30

A portable NMR

Lee, Jaehyuk January 2011 (has links)
No description available.

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