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Hydrogen quantum state resolved energy losses upon scattering from copper are studied using molecular beam techniques and quantum state-specific detection methods. Also clean copper and hydrogen and oxygen covered copper surfaces were studied using electron spectroscopy. There are many questions about the nature of molecule-surface dynamics and the processes. The relative role of the different degrees of freedom in the reaction and the importance of non-adiabatic effects have been two of these questions. These two questions motivated this work. Energy loss in the elastic scattering of H₂(v=1. J=1) and H₂(v=0, J=1) molecular quantum states is measured as a function of incident translational energy at two surface temperatures. The energy loss process is shown to agree to the Baule classical model for energy ranges 74-150 meV for the excited vibrationally state and 74-125 for the ground vibrational state. Results suggest that translational energy is more effective that vibrational energy in the observed process. Theoretical models have been able to explain several processes using nonadiabatic models where friction coefficient tensor is included. Results in this thesis suggest that the energy loss in the elastic scattering is a nonadiabatic one. Electron spectroscopy studies showed that the surface plasmon intensity is very sensitive to surface contamination. Using this property, surface-only sensitive virtual temperature programmed desorption (VTPD) is developed. A better understanding of unique behavior of hydrogen covered Cu(100) was gained. / text

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SuperB is a high luminosity e+e- collider experiment that is currently being designed to explore the flavour sector of particle physics. The detector at SuperB will contain a drift chamber, a gas filled device used to measure the momentum and identity of particles produced in the collisions. Particle identification in a drift chamber uses the measured amount of ionization deposited by the particle in the cells of the chamber, which provides a measurement of the particle speed. The ionization loss is traditionally measured by integrating the total charge released by the ionization after a gas amplification avalanche process. Since such a measurement has potentially large uncertainties associated with fluctuations in the gas amplification and other processes, it is possible that measuring the number of primary clusters of ionization caused by the particle could provide an improvement in the measurement of the ionization loss. The results of experiments performed at the University of Victoria and the TRIUMF laboratory M11 test beam using a SuperB drift chamber prototype to test the feasibility of counting clusters are presented here. The ability to separate muons and pions at the momenta explored in the TRIUMF testbeam was similar to the ability to separate pions and kaons at the higher momenta of SuperB. It was found that counting the clusters provides a significant improvement to particle identification when combined with the traditional measurement of the integrated charge. / Graduate

Thesis (Ph.D.)--McMaster University (Canada), 1995. / Source: Dissertation Abstracts International, Volume: 56-12, Section: B, page: 6709. Adviser: A. P. Hitchcock.

Thesis (Ph.D.) -- University of Glasgow, 2002. / Ph.D. thesis submitted to the Department of Physics and Astronomy and the Department of Chemistry, University of Glasgow, 2002. Includes bibliographical references. Print version also available.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

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Contact mechanics of rough surfaces and surface wear will be considered. Two types of failures are considered. The first involving rapidly growing failure and the second fatigue type surface failure as a result of repetitive application of load cycle. The first type of failure will be identified based on surface hysteresis energy loss in a load/unload cycle or examination of fracture toughness of the material near its rough surface. The above approach will be used to examine both types of failure in joint implants in the human body. These include consideration of implants for hip, ankle, spine and knee. In this case rapid and/or fatigue failures will be considered and related to anticipated implant life cycle based on implant recipient's tolerance level. Hence surface fidelity in terms of the biological host's tolerance of toxicity level due to wear will be used to develop life cycle prediction of an implant. The second application, rapid and fatigue wear will be examined in commonly used mechanical systems that include spur and helical gearing and rolling element bearings.

At its primary level (nm scale) bone is a nanocomposite consisting of a mineral (hydroxyapatite) phase which gives bone its strength and an organic (type I collagen) phase giving bone its fracture toughness. Hydroxyapatite, (HAP) Ca10(PO4)6(OH)2, is the most abundant mineral in the human body. Bone tissue has a complex hierarchical structure spanning multiple length scales (cm to nm). Characterization of mineral composition in biomineralized tissues such as bone at their primary level, is very challenging and requires instrumentation with nanometer-scale spatial resolution. Transmission electron microscopy (TEM) combines high spatial resolution with visual correlation of diffraction and elemental-composition data. Electron energy-loss spectroscopy (EELS) is a sensitive technique used to probe electronic structure at the molecular level. TEM-based EELS is the only available technique that can provide information about the chemical and coordination environment of minerals with nm scale spatial resolution. Prior studies in our group has developed a method to create biomimetic HAP using biomineralization routes inside the clay galleries of montmorillonite clay modified with amino acids (in-situ HAPclay). Incorporation of in-situ HAPclay into polymer scaffolds and seeding with human mesenchymal stem cells has enabled the cells towards differentiation into osteoblastic lineages without differentiating media. Because of the importance of these materials for bioengineering applications, TEM-EELS was used to evaluate differences and similarities among HAP, biomimetic in-situ HAPclay, modified MMT clay, and β-tricalcium phosphate. Osteogenesis imperfecta (OI), also known as brittle bone disease, is an inheritable disease characterized by increased bone fragility, low bone mass, and bone deformity caused primarily by mutation in collagen type I genes and is expressed as changes in structure and mechanics at the macrostructural level of bone. Therefore the mineralization of HAP in OI bone and the molecular basis of OI bone disease makes this an interesting system for molecular-level investigations. Small changes in the valence band and outer electronic structures of the diseased bone have been revealed through EELS. These small changes observed in the electron energy-loss spectra of the OI bone appear to play important biological roles towards development of the disease. / National Science Foundation under Grant Nos. 0619098, 0821655, 0923354, and 1229417