Thesis (M. Phil.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 90-97).

Thesis (Ph. D.)--University of Idaho, 2006. / Abstract. "August, 2006." Includes bibliographical references (leaves 113-122). Also available online in PDF format.

Modern solid-state nuclear magnetic resonance (NMR) methodologies are applied to investigate two spin-5/2 nuclei, Zn-67 and Al-27, in different coordination environments in order to characterize the magnitudes and orientations of their electric field gradient (EFG) and nuclear magnetic shielding tensors. The advantages of using high (21.1 T) applied magnetic fields for detecting Zn-67 directly at ambient temperatures, using the quadrupolar Carr-Purcell Meiboom-Gill (QCPMG) pulse sequence and the stepped-frequency technique, are demonstrated by the successful investigation of the different zinc sites in several zinc-amino acid coordination compounds, and in the more complex polymorphs of the zinc-insulin hexamers. In all systems, the high-field Zn-67 NMR spectra are dominated only by the quadrupolar interaction. The first two Zn-67 NMR spectra of pentacoordinated zinc sites are reported and analyzed. The experimental results are corroborated by ab initio and density functional theory (DFT) calculations of the Zn-67 NMR parameters in order to gain better understanding of the zinc local electronic environments. Solid-state Al-27 NMR is applied to study three commercial aluminum-phthalocyanine dyes. Solid-state Al-27 NMR experiments, including multiple-quantum magic-angle-spinning (MQMAS) and quadrupolar Carr-Purcell Meiboom-Gill (QCPMG), are employed at multiple high magnetic field strengths (11.7, 14.1 and 21.1 T) to determine the composition and number of aluminum distinct sites in these dyes. The quadrupolar parameters for each Al-27 site are determined from spectral simulations, with quadrupolar coupling constants ranging from 5.40 to 10.0 MHz and asymmetry parameters ranging from 0.10 to 0.50, and compare well with the results of quantum chemical calculations of these tensors. The largest Al-27 chemical shielding anisotropy (CSA), with a span of 120 ppm, observed directly in a solid material is also reported. The combination of MQMAS and computational chemistry are used to interpret the presence of multiple aluminum sites in two of the three samples.

Modern solid-state nuclear magnetic resonance (NMR) methodologies are applied to investigate two spin-5/2 nuclei, Zn-67 and Al-27, in different coordination environments in order to characterize the magnitudes and orientations of their electric field gradient (EFG) and nuclear magnetic shielding tensors. The advantages of using high (21.1 T) applied magnetic fields for detecting Zn-67 directly at ambient temperatures, using the quadrupolar Carr-Purcell Meiboom-Gill (QCPMG) pulse sequence and the stepped-frequency technique, are demonstrated by the successful investigation of the different zinc sites in several zinc-amino acid coordination compounds, and in the more complex polymorphs of the zinc-insulin hexamers. In all systems, the high-field Zn-67 NMR spectra are dominated only by the quadrupolar interaction. The first two Zn-67 NMR spectra of pentacoordinated zinc sites are reported and analyzed. The experimental results are corroborated by ab initio and density functional theory (DFT) calculations of the Zn-67 NMR parameters in order to gain better understanding of the zinc local electronic environments. Solid-state Al-27 NMR is applied to study three commercial aluminum-phthalocyanine dyes. Solid-state Al-27 NMR experiments, including multiple-quantum magic-angle-spinning (MQMAS) and quadrupolar Carr-Purcell Meiboom-Gill (QCPMG), are employed at multiple high magnetic field strengths (11.7, 14.1 and 21.1 T) to determine the composition and number of aluminum distinct sites in these dyes. The quadrupolar parameters for each Al-27 site are determined from spectral simulations, with quadrupolar coupling constants ranging from 5.40 to 10.0 MHz and asymmetry parameters ranging from 0.10 to 0.50, and compare well with the results of quantum chemical calculations of these tensors. The largest Al-27 chemical shielding anisotropy (CSA), with a span of 120 ppm, observed directly in a solid material is also reported. The combination of MQMAS and computational chemistry are used to interpret the presence of multiple aluminum sites in two of the three samples.

As técnicas de Espectroscopia de Alta Resolução em Sólidos e Relaxação por RMN são largamente utilizadas no estudo da estrutura e dinâmica de polímeros. Neste trabalho estudamos, utilizando estas técnicas, duas classes distintas de polímeros: os condutores iônicos e os condutores eletrônicos. O polímero condutor iônico estudado foi o Diesterato de Polietileno Glicol (PEGD) complexado com sais de metais alcalinos, LiClO4 ou NaClO4. A metodologia básica que empregamos para o estudo destes materiais foi a análise da forma de linha e do tempo de relaxação longitudinal para os núcleos associados tanto aos portadores de carga, 7Li e 23Na, quanto à cadeia polimérica, 1H e 13C. Todas estas medidas foram realizadas em função da temperatura e da concentração de sal de metal alcalino presente na amostra. Estudos adicionais, por condutividade elétrica, análise térmica e viscosidade foram realizados para complementar o conhecimento obtido por RMN sobre a mobilidade e estrutura das cadeias poliméricas e dos portadores de carga. Os polímeros com ligações de elétrons-\'pi\' conjugados apresentam propriedades eletrônicas especiais, particularmente a condutividade elétrica, e formam uma classe de polímeros condutores eletrônicos que podem ser facilmente oxidados ou reduzidos através de um agente dopante. Estudamos dois polímeros deste tipo: As polianilinas dopadas com 1H ou 7Li. A metodologia básica que empregamos para o estudo destes polímeros foi a análise das formas de linhas espectrais de um dos núcleos que compõem a cadeia polimérica, 13C, e de um dos agentes dopantes, 7Li, em função do método de preparação e da condutividade elétrica, de forma a poder elucidar características estruturais e dinâmicas deste grupo de polímeros. A partir do estudo destas duas classes de polímeros, conseguimos coletar uma quantidade muito grande de resultados experimentais por RMN, a partir de diferentes núcleos atômicos, que contribuíram para elucidar várias de suas características estruturais e dinâmicas / High resolution solid-state NMR spectroscopic techniques are widely used in the study of polymer structure and dynamics. In the present work we are studying, with the employment of these techniques, two distinct kinds of polymers: the ionic conductors and the electronic conductors. The ionic conductor polymer considered was the Poliethyleneglycol Distereate - 400)/MclO4, (M=Li,Na), DPEG/MclO4. The basic methodology employed for the study of these materials were the line shape analysis of the resonance lines and the longitudinal relaxation time, for the nuclei associated with the charge carriers, 7Li and 23Na, and with the polymeric chain, 1H and 13C. The measurements were related to temperature and to the alkali metal salt concentration in the sample. Additional studies, of electrical conductivity, thermal analysis and viscosity were also conducted for the complementation of the information obtained by NMR about the mobility and structure of polymeric chains and the charge carriers. The polymers with conjugated n-electron bounds present special electronic properties, particularly related to the electrical conductivity, and are easily oxidized or reduced by the action of a doping agent. We studied two of these kind of polymers: the 1H and 7Li doped Polyaniline. The basic methodology employed for the study of these polymers was the line shape analysis of the resonance lines related to one of the component nuclei of the polymeric chain, 13C , and the lines related to one of doping agents, 7Li, as a function of the preparation method and the electrical conductivity, as a way of elucidate structural and dynamic characteristics of this class of polymers. From the study of these two classes of polymers we could collect a huge quantity of NMR data from different atomic nuclei, and it led to the elucidation of important structural and dynamic characteristics of the polymers

The effect of temperature on soil behaviour has been the subject of many studies in recent years due to an increasing number of projects related to the application of high temperature to soil. One example is the construction of facilities for the disposal of hot high level nuclear waste canisters (150-200C) several hundred meters underground in the clay formations. Despite this, the effects and mechanism by which temperature affects the soil properties and behaviour are not fully known. A limited amount of reliable experimental data, technological difficulties and experimental methods employed by different researchers could have contributed to the uncertainties surrounding the soil behaviour at elevated temperature. Also several thermo-mechanical models have been developed for soil behaviour, but their validity needs to be examined by reliable experimental data. In this research, efforts have been made to improve the experimental techniques. Direct displacement measuring devices have been successfully used for the first time to measure axial and lateral displacements of clay samples during tests at various temperatures. The thermo mechanical behaviour of two reconstituted clays has been investigated by performing triaxial and permeability tests at elevated temperature. Undrained and drained triaxial tests were carried out on normally consolidated and over consolidated samples of M44 clay and Kaolin C1C under different effective stresses, and at temperatures between 22C and 100C. Permeability tests were carried out on samples of M44 clay at temperatures between 22C and 50C. The effects of temperature on permeability, volume change, pore pressure development, shear strength and stiffness, stress strain response and critical state parameters for different consolidation histories have been investigated by comparing the results at various temperatures. The results are also compared with the predictions of two models. It has been found that at elevated temperature the shear strength, friction angle and initial small strain stiffness reduce whereas permeability increases. The slope of the swelling line in the v-p� plane has been found to reduce with temperature. The slope of the isotropic normal consolidation line (INCL) and critical state line (CSL) in the v-p� plane have been observed to be independent of temperature, but both the INCL and the CSL shift downwards to lower locations as temperature increases. The deformations during drained cooling and re heating cycles have been found to be elastic and to simply reflect the expansivity of the soils solid particles. The thermal volume changes during undrained heating have been observed to be direct results of the thermal expansion of water and clay particles. The internal displacement measuring devices have been found to produce reliable data for the variation of strains at elevated temperature.

The phospholipid membrane is a self-assembled, dynamic molecular system that may exist alone in association with only water, or in complex systems comprised of multiple lipid types and proteins. In this dissertation the intra- and inter-molecular forces responsible for the atomistic, molecular and collective equilibrium structure and dynamics are studied by nuclear magnetic resonance spectroscopy (NMR). The multinuclear NMR measurements and various experimental techniques are able to provide data that enable the characterization of the hierarchical spatio-temporal organization of the phospholipid membrane. The experimental and theoretical studies conducted target membrane interactions ranging from model systems composed of only water and lipids, to multiple component domain forming membranes that are in association with peripheral and trans-membrane proteins. These measurements consisit of frequency spectrum lineshapes and nuclear-spin relaxation rates obtained using 2 H NMR, 13 C NMR, 31 P NMR and 1 H NMR. The changes of these experimental observables are interpreted within a statistical thermodynamic framework that allows the membrane structure, activation energies, and correlation times of motion to be determined. The cases presented demonstrate how fundamental principles of NMR spectroscopy may be applied to a host of membranes, leading to the biophysical characterization of membrane structure and dynamics.

The effect of temperature on soil behaviour has been the subject of many studies in recent years due to an increasing number of projects related to the application of high temperature to soil. One example is the construction of facilities for the disposal of hot high level nuclear waste canisters (150-200C) several hundred meters underground in the clay formations. Despite this, the effects and mechanism by which temperature affects the soil properties and behaviour are not fully known. A limited amount of reliable experimental data, technological difficulties and experimental methods employed by different researchers could have contributed to the uncertainties surrounding the soil behaviour at elevated temperature. Also several thermo-mechanical models have been developed for soil behaviour, but their validity needs to be examined by reliable experimental data. In this research, efforts have been made to improve the experimental techniques. Direct displacement measuring devices have been successfully used for the first time to measure axial and lateral displacements of clay samples during tests at various temperatures. The thermo mechanical behaviour of two reconstituted clays has been investigated by performing triaxial and permeability tests at elevated temperature. Undrained and drained triaxial tests were carried out on normally consolidated and over consolidated samples of M44 clay and Kaolin C1C under different effective stresses, and at temperatures between 22C and 100C. Permeability tests were carried out on samples of M44 clay at temperatures between 22C and 50C. The effects of temperature on permeability, volume change, pore pressure development, shear strength and stiffness, stress strain response and critical state parameters for different consolidation histories have been investigated by comparing the results at various temperatures. The results are also compared with the predictions of two models. It has been found that at elevated temperature the shear strength, friction angle and initial small strain stiffness reduce whereas permeability increases. The slope of the swelling line in the v-p� plane has been found to reduce with temperature. The slope of the isotropic normal consolidation line (INCL) and critical state line (CSL) in the v-p� plane have been observed to be independent of temperature, but both the INCL and the CSL shift downwards to lower locations as temperature increases. The deformations during drained cooling and re heating cycles have been found to be elastic and to simply reflect the expansivity of the soils solid particles. The thermal volume changes during undrained heating have been observed to be direct results of the thermal expansion of water and clay particles. The internal displacement measuring devices have been found to produce reliable data for the variation of strains at elevated temperature.

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