Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 2003. / Includes bibliographical references (leaves 285-292).

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.

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Lai Chun Hei Gary = 錳氧化物-鈮摻雜之鈦酸鍶異構結的輸運特性 / 黎鎮禧. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Lai Chun Hei Gary = Meng yang hua wu-ni shan za zhi tai suan si yi gou jie de shu yun te xing / Li Zhenxi. / Acknowledgement --- p.i / Abstract --- p.ii / 論文摘要 --- p.iv / Table of contents --- p.vi / List of Figures --- p.x / List of Tables --- p.xv / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Introduction to perovskite manganites and niobium doped strontium titanate --- p.1-1 / Chapter 1.1.1 --- Structure and properties of perovskite manganites --- p.1-1 / Chapter 1.1.2 --- Structure and properties of niobium doped strontium titanate --- p.1-4 / Chapter 1.1.3 --- Phase transition in perovskite manganites --- p.1-9 / Chapter 1.1.4 --- Charge ordering and small polaron theory in PCMO --- p.1-15 / Chapter 1.1.5 --- Colossal Magnetoresistance (CMR) in perovskite manganites --- p.1-19 / Chapter 1.16 --- Review of semiconducting junction between perovskite manganites and niobium doped strontium titanate --- p.1-23 / Chapter 1.2 --- Research motivation --- p.1-28 / Chapter 1.3 --- Scope of this thesis --- p.1-29 / References --- p.1-31 / Chapter Chapter 2 --- Experimental details / Chapter 2.1 --- Thin film deposition --- p.2-1 / Chapter 2.1.1 --- Facing-target sputtering --- p.2-1 / Chapter 2.1.2 --- Vacuum system --- p.2-3 / Chapter 2.1.3 --- Fabrication and characterization of manganites targets --- p.2-4 / Chapter 2.1.4 --- Substrate --- p.2-7 / Chapter 2.1.5 --- Deposition procedure --- p.2-8 / Chapter 2.1.6 --- Silver electrode coating apparatus --- p.2-10 / Chapter 2.2 --- Annealing systems --- p.2-12 / Chapter 2.2.1 --- Vacuum annealing system --- p.2-12 / Chapter 2.2.2 --- Oxygen annealing system --- p.2-14 / Chapter 2.3 --- Characterization --- p.2-16 / Chapter 2.3.1 --- Profilometer --- p.2-16 / Chapter 2.3.2 --- X-ray diffractometer --- p.2-16 / Chapter 2.3.3 --- Resistance measurement system --- p.2-18 / Chapter 2.3.4 --- Current-voltage characteristics measurement system --- p.2-20 / References --- p.2-23 / Chapter Chapter 3 --- Epitaxial LCMO/STON heterojunction / Chapter 3.1 --- Four point and two point I-V measurement --- p.3-1 / Chapter 3.2 --- Magnetic phase transition of LCMO revealed by four point I-V measurement of LCMO/STON heteroj unction --- p.3-8 / Chapter 3.3 --- Oxygen annealing effect on LCMO/STON heteroj unction --- p.3-14 / Chapter 3.4 --- Positive colossal Magnetoresistance in LCMO/STON heteroj unction --- p.3-16 / References --- p.3-23 / Chapter Chapter 4 --- Epitaxial PCMO/STON heterojunction / Chapter 4.1 --- Ohmic contact for PCMO thin films --- p.4-1 / Chapter 4.2 --- PCMO charge ordering and magnetic phase transition --- p.4-9 / Chapter 4.3 --- Four point I-V measurement of PCMO/STON heterojunction --- p.4-14 / References --- p.4-16 / Chapter Chapter 5 --- Epitaxial LCMO/PCMO/STON junction / Chapter 5.1 --- Tunneling junction fabrication --- p.5-1 / Chapter 5.2 --- Structural characterizations --- p.5-2 / Chapter 5.3 --- PCMO magnetic phase transition revealed by I-V measurement of LCMO/PCMO/STON tunneling junction --- p.5-3 / Chapter 5.4 --- Energy band structure of perovskite manganites --- p.5-11 / Chapter 5.4.1 --- Introduction to energy band of perovskite manganites and STON --- p.5-11 / Chapter 5.4.2 --- Temperature dependent band structure of LCMO explained by diffusion voltage of LCMO/STON heterojunction --- p.5-18 / References --- p.5-22 / Chapter Chapter 6 --- Conclusions / Chapter 6.1 --- Conclusion --- p.6-1 / Chapter 6.2 --- Future outlook --- p.6-3

Cheung, Wing Kin = 應變及間隔效應對La0.67Sr0.33MnO3摻雜Pr0.67Ca0.33MnO3的傳導特性的影響之研究 / 張榮健. / On t.p. "0.67", "0.33" and "3" are subscripts. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 89-93). / Text in English; abstracts in English and Chinese. / Cheung, Wing Kin = Ying bian ji jian ge xiao ying dui La0.67Sr0.33MnO3 shan za Pr0.67Ca0.33MnO3 de chuan dao te xing de ying xiang zhi yan jiu / Zhang Rongjian. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Development of magnetoresistance materials --- p.1 / Chapter 1.2 --- What is magnetoresistance? --- p.1 / Chapter 1.2.1 --- Anisotropic magnetoresistance --- p.2 / Chapter 1.2.2 --- Giant magnetoresistance (GMR) --- p.3 / Chapter 1.2.3 --- Colossal magnetoresistance (CMR) --- p.4 / Chapter 1.3 --- Possible origins of CMR in manganites --- p.6 / Chapter 1.3.1 --- Tolerance factor --- p.6 / Chapter 1.3.2 --- Double exchange mechanism --- p.8 / Chapter 1.3.3 --- Jahn-Teller distortion --- p.11 / Chapter 1.3.4 --- Charge-ordering and phase separation --- p.13 / Chapter 1.4 --- Movtiation --- p.17 / Chapter 1.5 --- Literature review --- p.18 / Chapter 1.5.1 --- Single-layer manganite thin films --- p.18 / Chapter 1.5.2 --- Multilayer system - manganites with insulating spacers --- p.19 / Chapter 1.6 --- Scope of thesis --- p.20 / Chapter 2 --- Instrumentation --- p.21 / Chapter 2.1 --- Sample preparation --- p.21 / Chapter 2.1.1 --- Facing-target sputtering technique (FTS) --- p.21 / Chapter 2.1.2 --- Deposition system --- p.24 / Chapter 2.2 --- Annealing system --- p.26 / Chapter 2.2.1 --- Oxygen annealing --- p.26 / Chapter 2.3 --- Sample characterization --- p.28 / Chapter 2.3.1 --- X-ray diffraction (XRD) --- p.28 / Chapter 2.3.2 --- Alpha - step profiler --- p.30 / Chapter 2.3.3 --- Transport property measurement --- p.30 / Chapter 3 --- Preparation and characterization of single-layer thin films --- p.32 / Chapter 3.1 --- Introduction --- p.32 / Chapter 3.2 --- Fabrication and characteristization of the sputtering targets --- p.32 / Chapter 3.3 --- Deposition procedure --- p.36 / Chapter 3.3.1 --- Preparation of substrate --- p.36 / Chapter 3.3.2 --- Deposition process --- p.36 / Chapter 3.4 --- Parameters related to epitaxial growth of LPSCMO thin films --- p.37 / Chapter 3.4.1 --- Substrate materials --- p.37 / Chapter 3.4.2 --- Substrate temperature --- p.38 / Chapter 3.4.3 --- Oxygen partial pressure --- p.38 / Chapter 4 --- Thickness and strain effects in epitaxial LPSCMO thin films --- p.43 / Chapter 4.1 --- Introduction --- p.43 / Chapter 4.2 --- Structural characterization of LPSCMO thin films --- p.45 / Chapter 4.2.1 --- Thickness effect --- p.45 / Chapter 4.2.2 --- Strain effect --- p.49 / Chapter 4.3 --- Transport properties and magnetoresistance measurement --- p.51 / Chapter 4.3.1 --- Thickness effect --- p.51 / Chapter 4.3.2 --- Strain effect --- p.60 / Chapter 4.4 --- Discussion --- p.63 / Chapter 5 --- Effect of spacer in [LPSCMO/SCuO] multilayer --- p.65 / Chapter 5.1 --- Sample preparation --- p.65 / Chapter 5.2 --- Characterization of as-deposited multilayer samples --- p.67 / Chapter 5.2.1 --- Structural anaylsis --- p.67 / Chapter 5.2.2 --- Resistance measurement --- p.72 / Chapter 5.3 --- Oxygen-annealing treatment --- p.76 / Chapter 5.3.1 --- Introduction --- p.76 / Chapter 5.3.2 --- Structural anaylsis --- p.77 / Chapter 5.3.3 --- Resistance measurement --- p.78 / Chapter 5.4 --- Discussion --- p.85 / Chapter 6 --- Conclusion --- p.87 / Chapter 6.1 --- Summary --- p.87 / Chapter 6.2 --- Future outlook --- p.88 / Bibliography --- p.89

Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (Ph.D. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references (leaves 46-66).

Thesis (Ph.D.)--University of Wollongong, 2004. / Typescript. Includes bibliographical references.

Understanding and establishing reaction mechanisms is an important area in heterogeneous catalysis. This dissertation describes the use of in situ laser Raman spectroscopy combined with kinetic measurements and dynamic experiments to determine the mechanism of catalytic reactions. Two cases involving ozone reactions on manganese oxide catalysts were treated. Manganese oxide was chosen because it is the most active of the transition metal oxides for ozone decomposition and because it is a well-known catalyst for complete oxidation reactions. The first case studied was that of the ozone decomposition reaction on a supported manganese oxide catalyst. An adsorbed species with a Raman signal at 884 cm-1 was observed and assigned to a peroxide species based on results of in situ Raman spectroscopy, 18O isotopic substitution measurements, and ab initio MO calculations. The reaction pathway of ozone decomposition was elucidated with carefully designed isotopic experiments. The reaction sequence was found to involve two irreversible, kinetically significant steps: 1) dissociative adsorption of ozone to form a peroxide species and an atomic oxygen species, and 2) desorption of the peroxide intermediate. The kinetic behavior of the peroxide species and the overall decomposition reaction were investigated to test the validity of the proposed sequence. The transient kinetics were found to be consistent with the steady state kinetics, and both were well represented by the two-step sequence, indicating that the proposed reaction sequence accurately described the mechanism of decomposition. The surface was found to be non-uniform, with activation energies that varied linearly with coverage. At zero surface coverage the activation energy for ozone adsorption was found to be 6.2 kJ mol-1, while that for desorption of the peroxide species was found to be 69.0 kJ mol-1. The second case investigated was that of ethanol oxidation using ozone on alumina and silica supported manganese oxide catalysts. Ethanol was found to react with ozone at lower temperatures than with oxygen, and also with a lower activation energy. The reaction kinetics was found to be well described by a power law equation with the reaction orders on ozone and ethanol being 0.89 and 0.81 respectively. The oxidation reactivity was found to be closely related to that of ozone decomposition, suggesting an important role of ozone decomposition in the reaction mechanism. In situ laser Raman spectroscopic studies showed the existence of adsorbed ethoxide species on the catalyst surface under reaction conditions, however, at a much lower concentration than when oxygen alone was used as the oxidant. Transient experiments provided direct evidence that surface peroxide (an adsorbed species due to ozone) and surface ethoxide (an adsorbed species due to ethanol) reacted with each other on the catalyst surface. / Ph. D.