Water and lipid-soluble meat flavour precursors are gradually formed post-mortem via biochemical reactions. Storage time and temperature can affect final flavour precursor concentrations which in turn will affect the sensory quality of cooked meat. Selected key flavour precursors were monitored in Bison bison longissimus dorsi muscles from six animals stored at 2, 4, 8, 15 and 21 days at 4°C, in order to evaluate the effect of post-mortem conditioning on the formation of flavour precursors. Results were correlated with sensory data obtained using quantitative descriptive analysis with 8 trained panelists. While lipid-soluble flavour precursors remained mostly unchanged, significant increases (P<0.05) in concentrations of water-soluble flavour precursors including reducing sugars (eg. ribose, xylose), free amino acids (eg. valine, leucine) and adenosine-5’-triphosphate (ATP) degradation products (eg. inosine and hypoxanthine) were obtained with chilled storage conditioning post-mortem. The overall balance and correlations of water-soluble flavour precursors with storage day 15 and 21 were reported and can potentially impact the eating quality of cooked bison meat.

A novel type of white light emitting semiconductor quantum dot was characterized at the ensemble and single-molecule level. This kind of semiconductor nanocrystal can be made into white light emitting diodes, which have the potential to replace conventional lighting sources. The quantum dots used in this thesis consisted of a cadmium selenide (CdSe) core, capped with ZnS, and have a surface polymer coating of poly(acrylic acid) (PAA). We have characterized the quantum dot size distribution by using dynamic light scattering (DLS), transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV-Vis spectroscopy. Based on these measurements, it is clear that the white quantum dots are polydisperse, with a core size of 2.4 ± 0.5 nm, though the polymer coating swells considerably in aqueous solution. In order to explore the optical properties, the absorption and emission spectra of the ensemble quantum dots solution were measured and compared to “standard” commercial quantum dots. The emission spectrum of the white quantum dots showed two peaks, a strong blue emission peak and a weaker red emission peak. The fluorescence quantum yield of the white quantum dots was found to be less than that of commercial quantum dots. To explore the behavior of individual quantum dots, spatially-resolved single-molecule images were obtained by a dual-view single molecule fluorescence microscopy with a beam splitter which can separate the emission into red and blue components. It was found that individual white CdSe nanocrystals have a broad emission spectrum and the samples did not consist of a mixed population of red emitters and blue emitters. These results suggest that these white light emitting quantum dots can be used for pure white light LEDs and are a good candidate for the replacement for conventional lighting sources.

Water and lipid-soluble meat flavour precursors are gradually formed post-mortem via biochemical reactions. Storage time and temperature can affect final flavour precursor concentrations which in turn will affect the sensory quality of cooked meat. Selected key flavour precursors were monitored in Bison bison longissimus dorsi muscles from six animals stored at 2, 4, 8, 15 and 21 days at 4°C, in order to evaluate the effect of post-mortem conditioning on the formation of flavour precursors. Results were correlated with sensory data obtained using quantitative descriptive analysis with 8 trained panelists. While lipid-soluble flavour precursors remained mostly unchanged, significant increases (P<0.05) in concentrations of water-soluble flavour precursors including reducing sugars (eg. ribose, xylose), free amino acids (eg. valine, leucine) and adenosine-5’-triphosphate (ATP) degradation products (eg. inosine and hypoxanthine) were obtained with chilled storage conditioning post-mortem. The overall balance and correlations of water-soluble flavour precursors with storage day 15 and 21 were reported and can potentially impact the eating quality of cooked bison meat.

Thesis (Ph.D.) -- McMaster University, 1999. / Includes bibliographical references. Also available via World Wide Web.

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 150-159). Also available on the Internet.

Thesis (Ph. D.)--University of Oregon, 2000. / Title from title screen. Paging within document: xvii, 167 p. : ill. Includes vita and abstract. Includes bibliographical references (p. 149-167).

Thesis (Ph.D.) - University of Queensland, 2006. / Includes bibliography.

Thesis (Ph. D.)--University of Oregon, 2000. / Includes vita and abstract. Includes bibliographical references (p. 149-167). Also available for download via the World Wide Web; free to University of Oregon users.

Adviser: Kenneth M. Doxsee. xvii, 167 p. / A print copy of this title is available through the UO Libraries under the call number: SCIENCE QD412.M7 B35 2000 / The chemistry of three organometallic systems in water was studied with the goal of understanding more fully the reactivity of organometallic complexes in aqueous environments. Molybdocene complexes were found to catalyze C-H bond activation reactions in water. The catalytically active solutions were prepared from the molybdocene dimer [Cp

Supramolecular chemistry - chemistry of non-covalent bonds including different type of intermolecular interactions viz., ion-pairing, ion-dipole, dipole-dipole, hydrogen bonding, cation-p and Van der Waals forces. Applications based on supramolecular concepts for developing catalysts, molecular wires, rectifiers, photochemical sensors have been evolved during recent years. Mimicking natural photosynthesis to build energy harvesting devices has become important for generating energy and solar fuels that could be stored for future use. In this dissertation, supramolecular chemistry is being explored for creating light energy harvesting devices. Photosensitization of semiconductor metal oxide nanoparticles, such as titanium dioxide (TiO2) and tin oxide (SnO2,), via host-guest binding approach has been explored. In the first part, self-assembly of different porphyrin macrocyclic compounds on TiO2 layer using axial coordination approach is explored. Supramolecular dye sensitized solar cells built based on this approach exhibited Incident Photon Conversion Efficiency (IPCE) of 36% for a porphyrin-ferrocene dyad. In the second part, surface modification of SnO2 with water soluble porphyrins and phthalocyanine resulted in successful self-assembly of dimers on SnO2 surface. IPCE more than 50% from 400 - 700 nm is achieved for the supramolecular self-assembled heterodimer photocells is achieved. In summary, the axial ligation and ion-pairing method used as supramolecular tools to build photocells, exhibited highest quantum efficiency of light energy conversion with panchromatic spectral coverage. The reported findings could be applied to create interacting molecular systems for next generation of efficient solar energy harvesting devices.