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Predicition of the molecular structure of ill-defined hydrocarbons using vibrational, 1H, and 13C NMR spectroscopyObiosa-Maife, Collins 11 1900 (has links)
This represents a proof-of-concept study of the appropriateness of vibrational and NMR spectroscopy for predicting the molecular structure of large molecules on the basis of a library of small molecules. Density Functional Theory (DFT) B3LYP/6-311G was used generate all spectra. 20 model compounds comprising two multiple-ringed polynuclear aromatic hydrocarbons (PAHs) connected by varying aliphatic chain-lengths were investigated. A least squares optimization algorithm was developed to determine the contribution of molecular subunits in the model compounds. 1H and 13C NMR spectroscopy failed to identify subunits unambiguously even with a constrained library. By contrast, IR and Raman results independently identified 40% and 65% respectively and jointly more than 80 % of the aromatic groups present; however, the aliphatic chain-length was poorly defined in general. IR and Raman spectroscopy are a suitable basis for spectral decomposition and should play a greater role in the identification of ringed subunits present in ill-defined hydrocarbons / Chemical Engineering
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Porous Membrane-Based Sensor Devices for Biomolecules and Bacteria DetectionTsou, Pei-Hsiang 2012 August 1900 (has links)
Biological/biochemistry analyses traditionally require bulky instruments and a great amount of volume of biological/chemical agents, and many procedures have to be performed in certain locations such as medical centers or research institutions. These limitations usually include time delay in testing. The delays may be critical for some aspects such as disease prevention or patient treatment. One solution to this issue is the realization of point-of-care (POC) testings for patients, a domain in public health, meaning that health cares are provided near the sites of patients using well-designed and portable medical devices. Transportation of samples between local and central institutions can therefore be reduced, facilitating early and fast diagnosis. A closely related topic in engineering, lab-on-a-chip (LOC), has been discussed and practiced in recent years. LOC emphasizes integrating several functions of laboratory processes in a small portable device and performing analysis using only a very small amount of sample volume, to achieve low-cost and rapid analysis. From an engineer's point of view, LOC is the strategy to practice the idea of POC testing.
This dissertation aimed at exploring the POC potentials of porous membrane-base LOC devices, which can be used to simplify traditional and standard laboratory procedures. In this study, three LOC prototypes are shown and discussed. First the protein sensor incorporating with silica nanofiber membrane, which has shown 32 times more improvement of sensitivity than a conventional technique and a much shorter detection time; secondly the bacteria filter chip that uses a sandwiched aluminum oxide membrane to stabilize the bacteria and monitor the efficacy of antibiotics, which has reduced the test time from 1 day of the traditional methods to 1 hour; the third is the sensor combining microfluidics and silica nanofiber membrane to realize Surface Enhanced Raman Spectroscopy on bio-molecules, which has enhancement factor 10^9 and detection limit down to nanomolar, but simple manufacturing procedures and reduced fabrication cost. These results show the porous-base membrane LOC devices may have potentials in improving and replacing traditional detection methods and eventually be used in POC applications.
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Studies on defect and contact properties of ZnSnP₂ for application to thin film photovoltaics / 薄膜太陽電池への応用に向けたZnSnP₂の欠陥および電極の特性に関する研究Kuwano, Taro 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23901号 / 工博第4988号 / 新制||工||1779(附属図書館) / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 田中 功, 教授 杉村 博之, 准教授 野瀬 嘉太郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Vibrational microspectroscopy of bacterial coloniesGoodwin, James Royce January 2006 (has links)
Vibrational spectroscopy, mainly infrared spectroscopy, has been applied to bacteria, yeast and archaea cells for many years, for example, for the purpose of developing a rapid method of identification. More recently microcolonies have been used for consistency with the preparation and culture protocols of traditional microbiological methods. Heterogeneity of microcolonies has not been well studied. Investigation of heterogeneity may provide detailed biochemical information leading to an understanding of how colonies grow and the link to the growth cycle. Investigation of regions within bacterial colonies using FT-IR microspectroscopy was applied to two prokaryotes, the Gram-negative archaeon Halobacterium salinarium and the Gram-positive bacterium Bacillus stearothermophilus. Two-dimensional maps of the entire colony and point maps, spectra taken from key regions such as the periphery and centre of the colony, were acquired. The approximate size of the colonies ranged from 250-950 μm. The infrared data for the Gram-negative archaeon, H. salinarium supports that for the Gram-positive bacterium, B. stearothermophilus, despite the microorganisms being of different domains and Gram types. It was concluded that the periphery of the microcolony approximately equates to the exponential growth phase (and possibly the lag phase) where the younger cells reside, while the centre approximates to the death and stationary phases. However the spatial resolution proved to be a limiting factor, so Raman microspectroscopy was employed to address this. Raman spectra across the diameter of microcolonies ranging from 100-300 μm of the pigmented bacterial species Halobacterium salinarium revealed variations in the carotenoid bands. It was suggested that these variations correspond to growth rings, which relate to the growth cycle and the consolidation and migration phase of the cells. The carotenoid variation was rather clear mainly due to the enhanced spectral intensity due to resonance with the laser excitation source. Hence, pigmented bacterial colonies are ideal to study by Raman spectroscopy. The results of this particular aspect of the research are to be published in the Journal of Raman Spectroscopy [1]. In addition, a connection between the consolidation and migration phases and the phases of the growth cycle has been postulated as a novel hypothesis to link the periodic dynamics of the colony and the growth mechanisms at the cellular level. The Raman microspectroscopic study was extended to non-pigmented bacterial colonies directly on the growth medium. This was a more difficult endeavour as the spectra taken do not have the resonance enhanced advantage of a pigmented bacterium. In addition the sampling volume can consist of variable amounts of growth medium thus decreasing the signal-to-noise ratio and reducing the accuracy of subsequent spectral calculations. However, this was overcome to a large extent by the use of confocal microscopy. The non-pigmented bacterial colonies investigated were Bacillus stearothermophilus and Bacillus subtilis. Analysis, by band area ratios and by chemometric approaches, of radial line map spectra of both Bacillus species revealed variation of nucleic acid concentration. The higher nucleic acid concentration is likely to be a result of cells in the exponential growth phase as rapid growth of new cells is occurring.
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The controlled ball milling of titanium and carbon to form TiC /Lohse, Benjamin H. January 2005 (has links)
Thesis (Ph. D.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references (leaf 111-114).
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Time-resolved resonance raman and density functional theory studies of the photochemistry of (S)-ketoprofenChuang, Yung-ping. January 2008 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2008. / Includes bibliographical references (leaf 76-77) Also available in print.
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Time-resolved resonance raman and density functional theory studies of selected arylnitrenium ions and their reactions with guanosine derivatives and aryl azidesXue, Jiadan. January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2008. / Includes bibliographical references (leaves 140-147) Also available in print.
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Novel spectroscopic probes of sunscreens, initial excited-state structural dynamics and DNA photodamageOladepo, Sulayman Adeyemi. January 2010 (has links)
Thesis (Ph.D.)--University of Alberta, 2010. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Chemistry. Title from pdf file main screen (viewed on April 10, 2010). Includes bibliographical references.
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Vibrational and mechanical properties of 10 mol % Sc₂O₃-1 mol % CeO₂- ZrO₂ electrolyte ceramics for solid oxide fuel cellsLukich, Svetlana. January 2009 (has links)
Thesis (M.S.M.S.E.)--University of Central Florida, 2009. / Adviser: Nina Orlovskaya. Includes bibliographical references (p. 87-93).
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Adsorbate-substrate charge transfer excited states /Kambhampati, Patanjali, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 274-296). Available also in a digital version from Dissertation Abstracts.
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