Thesis (M.S.)--University of Nevada, Reno, 2005. / "August, 2005." Includes bibliographical references (leaves 76-78). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2005]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

Thesis (M.C.E.)--University of Delaware, 2006. / Principal faculty advisor: Michael J. Chajes, Dept. of Civil & Environmental Engineering. Includes bibliographical references.

Author's thesis (Ph. D.)--Technische Universiteit Delft, 2006. / Includes bibliographical references.

Mass spectrometry has shown its unique potential for studying the structure of proteins. Associated with various specific techniques (H/D exchange, ion mobility, gas-phase spectroscopy, multidimensional mass analysis), it has demonstrated to be an essential tool allowing primary structures to be analyzed and providing a lot of information about high order conformations. This work assesses the capabilities of these emerging mass spectrometry methods, and especially the gas-phase H/D exchange technique, for the structural analysis of nucleic acids. Gas-phase H/D exchange was first used to study single stranded oligonucleotides. The exchange reactions were performed with CD3OD in the collision cell of a 9.4 T FT-ICR MS. In these experimental conditions and in integrating the experimental and theoretical results, gas-phase H/D exchange was shown to be controlled by hydrogen accessibility and not by the chemical nature of the heteroatom bearing the exchangeable hydrogen. This allowed the presence of one structure or several conformers that possess different exchange properties to be detected. Moreover, when several structures were observed, increasing the internal energy of the ions at the entrance of the H/D exchange cell gave access to a qualitative estimation of the relative height of the isomerization barriers compared to the H/D exchange ones. Ion mobility experiments confirmed independently the H/D exchange results. Comparing the ion activation experiments for H/D exchange and for ion mobility revealed that the most compact conformer displays the fastest H/D exchange. This observation showed that H/D exchange and ion mobility provide us with complementary information because accessibility and macromolecule compactness are not univocally associated. Two other methods having independent principles of operations were sequentially combined. The fragmentation of a totally deuterated dinucleotide in exchangeable positions demonstrated the coexistence of several fragmentation channels. The latter were classified according to the involvement of non-labile or labile protons in the fragmentation process. Double resonance experiments were also performed and demonstrated the existence of consecutive fragmentation mechanisms. The involvement of labile, and therefore exchangeable protons in the fragmentation mechanism casts doubt on the use of tandem mass spectrometry to localize incorporated deuteriums in oligonucleotides. Finally, an exploratory work on the gas-phase H/D exchange of non-covalent complexes is presented.

Thesis (Ph. D.)--University of Chicago, Dept. of Physics, 2001. / Includes bibliographical references. Also available on the Internet.

Thesis--Teknillinen Korkeaukoulu, Otaniemi. / Includes bibliographical references.

Thesis--M. Phil., University of Hong Kong.

Thesis--M. Phil., University of Hong Kong, 1983.

Thesis (M. Phil.)--University of Hong Kong, 1989.

Lithium-ion batteries are the most promising rechargeable battery system for both vehicle applications and stationary storage of electricity produced from renewable sources such as solar and wind energies. However, the current lithium ion technology does not fully meet the requirements of these applications in terms of energy and power density. One approach to realizing a combination of high energy and power density is to use a composite cathode that consists of the high-capacity lithium-rich layered oxide Li[Li,Mn,Ni,Co]O2 and the high-voltage spinel oxide LiMn1.5Ni0.5O4. This dissertation explores the unique structural characteristics and their effect on the electrochemical performance of the layered-spinel composite oxide cathodes along with individual layered and spinel oxides over a wide voltage range (5.0 – 2.0 V). Initially, the effect of cation ordering on the electrochemical and structural characteristics of LiMn1.5Ni0.5O4 during cycling between 5.0 and 2.0 V were investigated by an analysis of the X-ray diffraction (XRD) and electrochemical data. Structural studies revealed that the cation ordering affects the size of the empty-octahedral sites in the spinel lattice. The differences in the size of the empty-octahedral sites affect the discharge profile below 3 V due to the variation in lattice distortion during lithium ion insertion into 16c octahedral sites. With the doped LiMn1.5Ni0.5-xMxO4 (M = Cr, Fe, Co, and Ga) spinels, different dopant ions have different effects on the degree of cation ordering due to the differences in ionic radii and surface-segregation characteristics. The compositional and wt.% variations of the layered and spinel phases from the nominal values in the layered-spinel composites were obtained by employing a joint XRD and neutron diffraction (ND) Rietveld refinement method. With the obtained composition and ex-situ XRD data, the mechanism for the increase in capacity and the facile phase transformation of the layered phase in the composite cathodes to a 3 V spinel-like phase during cycling was proposed. Investigations focused on synthesis temperature revealed that the electrochemical characteristics of the composites are highly affected by the synthesis temperature due to the change in the surface area of the sample and cation ordering of the spinel phase. In addition, the electrochemical performance of the lithium-rich layered oxide Li[Li,Mn,Ni,Co]O2 could be improved by blending it with a lithium-free insertion host VO2(B) and by controlling the amount of lithium ions extracted from the layered lattice during the first charge process. / text