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Abstract: X-ray absorption spectroscopy (XAS) and micro-synchrotron based X-ray fluorescence (micro-SXRF) are element specific spectroscopic techniques and have been proven to be valuable tools for the investigation of changes in the chemical environment of metal centres. XAS allows the determination of the oxidation state, the coordination motif of the probed element, the identity and the number of adjacent atoms and the absorber–ligand distances. It is further applicable to nearly all types of samples independent of their actual physical state (solid, liquid, gaseous) down to μM concentrations. Micro-SXRF can provide information on the distribution and concentration of multiple elements within a sample simultaneously, allowing for the chemical state of several elements within subcellular compartments to be probed. Modern third generation synchrotrons offer the possibility to investigate the majority of the biologically relevant elements. The biological mode of action of metal-based compounds often involves interactions with target and/or transport molecules. The presence of reducing agents may also give rise to changes in the coordination sphere and/or the oxidation state. XAS and micro-SXRF are ideal techniques for investigating these issues. This tutorial review introduces the use of XAS and micro-SXRF techniques into the field of inorganic medicinal chemistry. The results obtained for platinum, ruthenium, gallium, gold and cobalt compounds within the last few years are presented.

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Abstract: Higher whole grain cereal intakes are associated with substantially lower risks of type 2 diabetes, coronary heart disease, and hypertension. These reduced risks have been established in large prospective studies that now include millions of person-years of follow-up. We analyze the results of 11 major prospective studies to provide recommendations about whole grain consumption. The following review establishes the amount of whole grains that should ideally be consumed based on prospective evidence; defines the nature of whole grains; identifies that the whole grain evidence is robust and not due to confounding; and provides a detailed assessment of several potential mechanisms for the effect of whole grains on health. We draw the following conclusions. Firstly, to maintain health, 40 grams or more of whole grains should be consumed daily. This is about a bowl of whole grain breakfast cereal daily, but 80% of the population does not achieve this. Secondly, aleurone in bran is a critical grain component generally overlooked in favor of indigestible fiber. Live aleurone cells constitute 50% of millers' bran. They store minerals, protein, and the antioxidant ferulic acid, and are clearly more than just indigestible fiber. Finally, we suggest potential roles for magnesium, zinc, and ferulic acid in the development of chronic disease. If the results of prospective studies were applied to the life-style practices of modern societies there exists the potential for enormous personal health and public financial benefits.

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Abstract: This thesis investigates the use of X-ray Excited Optical Luminescence (XEOL) and Time Resolved X-ray Excited Optical Luminescence (TR XEOL) within the Earth sciences. The project contains two primary objectives, the first of which is the design and building of a high-resolution luminescence spectroscopy facility. This includes the installation and commissioning of the facility on the I18 microfocus beamline at Diamond, the UK's national synchrotron facility. In describing the system's design and commissioning, I explore many implications of the technique. The second objective is using this new facility to investigate a suite of minerals to develop new analytical techniques utilizing XEOL and TR XEOL spectroscopy for applications within the Earth sciences. An aspect of this investigation is to explore the potential of Time Resolved Optically Derived X-ray Absorption Spectroscopy (TR OD XAS) of substitute trace elements in minerals. To date CW OD XAS has been shown to have very limited application within the Earth sciences. (Soderholm et al., 1998-120) The thesis explores differences between photoluminescence (PL) and XEOL responses in mineral systems, and investigates how these differences can be exploited. Luminescence, the phenomenon upon which the thesis is based, is a complex and poorly utilised phenomena within Earth sciences, it is however, orders of magnitude more sensitive, than many of the more accepted techniques used for the detection of trace elements, on this basis alone I would suggest it deserves further consideration. Luminescence techniques have developed much further in other disciplines; I therefore have incorporated many descriptions, models, and interpretations from other disciplines in order to identify methodologies and techniques that have the potential to be utilized in the study and interpretation of luminescence within the Earth sciences. The thesis demonstrates that luminescence in minerals with measured lifetimes, as fast as ~ 20 ps exist. Previously the recorded luminescent lifetimes, for minerals, in the literature are measured in ns. This finding leads to the novel concept that the measurement of TR XEOL with ps resolution combined with the measurement of the intensity of a luminescent signal as a function of excitation can provide significant new insights into the nature of the emission and the luminescent processes. I explore and demonstrate the potential of using dose dependence techniques of continuous wave and TR XEOL as a new analytical technique. I also demonstrate the use of a technique used extensively within Biology has an application with Earth sciences. The methodology incorporates the calculation of the natural lifetime of an emission through the relationship between the absorption and emission coefficients. (Strickler and Berg, 1962). I discuss how knowledge of the natural lifetime of an emission allows quantification of luminescence through measurement of a modified lifetime of emission. The quantification of a luminescent emission has significant potential within the geosciences one example being the identification of disputed emissions. I also consider the potential to use TR XEOL techniques in mapping complex heterogeneous rocks and minerals.

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Abstract: Highly conductive and transparent ZnO films were synthesized by the reaction of diethyl zinc (in toluene) with methanol by dual source aerosol assisted chemical vapor deposition. These films displayed a stable sheet resistance of 7.2 ?/? and high transmission across the visible region comparable to commercial transparent conducting oxides (TCOs) based on oxides of tin or indium. Doping the zinc oxide structure with fluorine (trifluorotoluene) resulted in dense compact films with improved electrical properties than ZnO films with a sheet resistance of 4.5 ?/?. These films also displayed idealized surface texturing for photovoltaic applications. Fluorine concentration was 2 at.% determined by wavelength dispersive X-ray analysis (WDX). Aluminum doped zinc oxide films were also synthesized by introducing dopant amounts of trimethylaluminium solution (in toluene) into the system. These films exhibited low sheet resistances of 14 ?/?. The aluminum concentration in the films was 4 at.% determined by WDX