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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Desulfurdimerization of dithioacetals with tungsten hexacarbonyl.

January 1989 (has links)
Lam Lung Yeung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 73-76.
292

Invitro measurement of glucose concentration in water solution by optical methods.

January 2004 (has links)
Chu Lut-Hey. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 137-140). / Abstracts in English and Chinese. / Abstract --- p.II / Acknowledgement --- p.V / List of Tables --- p.IX / List of Figures --- p.X / List of Abbreviations --- p.XIII / Chapter 1 --- Introduction / Chapter 1.1 --- Objectives.l --- p.1 / Chapter 1.2 --- What is diabetes mellitus?. --- p.1 / Chapter 1.3 --- "Review of ""Technique for blood glucose measurement""" --- p.3 / Chapter 1.3.1 --- Conventional blood glucose meter --- p.4 / Chapter 1.3.2 --- Semi-invasive blood glucose meter --- p.5 / Chapter 1.3.3 --- Surfacelasmon resonance (SPR) method --- p.6 / Chapter 1.3.4 --- Non-invasive blood glucose meters --- p.7 / Chapter 1.4 --- Research directions --- p.8 / Chapter 1.5 --- Data analysis methods --- p.9 / Chapter 1.6 --- Organization of the thesis --- p.10 / Chapter 2 --- Spectral Data Analysis Methods / Chapter 2.1 --- What is spectral data? --- p.12 / Chapter 2.2 --- Nature of spectral data --- p.12 / Chapter 2.3 --- How to interpret the spectral data? --- p.15 / Chapter 2.3.1 --- Linear regression --- p.15 / Chapter 2.3.2 --- Multiple linear regression (MLR) --- p.17 / Chapter 2.3.2.1 --- Data reduction --- p.19 / Chapter 2.3.3 --- Bilinear modeling (BLM) --- p.21 / Chapter 2.3.3.1 --- artial least square regression (PLSR) --- p.23 / Chapter 2.3.3.2 --- Model reliability --- p.24 / Chapter 2.3.3.3 --- LS segmentation analysis --- p.25 / Chapter 2.4 --- Session discussion and conclusion --- p.27 / Chapter 3 --- Surfacelasmon Resonance (SPR) Experiments and Analysis / Chapter 3.1 --- Intrcduction --- p.29 / Chapter 3.2 --- Theory --- p.30 / Chapter 3.2.1 --- Maxwell's equations --- p.30 / Chapter 3.2.2 --- olarization of EM wave --- p.32 / Chapter 3.2.3 --- Boundary condition --- p.33 / Chapter 3.2.4 --- Total internal reflection --- p.37 / Chapter 3.2.5 --- hase shift of total internal reflection wave --- p.38 / Chapter 3.2.6 --- Kretschmannrism configuration --- p.38 / Chapter 3.2.7 --- Conditions affecting SPR --- p.41 / Chapter 3.3 --- Different SPR configuration systems --- p.44 / Chapter 3.3.1 --- rinciple of angular-based interrogation SPR setup --- p.44 / Chapter 3.3.2 --- rinciple of intensity-based interrogation SPR setup --- p.45 / Chapter 3.3.3 --- rinciple of wavelength-based interrogation SPR setup --- p.45 / Chapter 3.3.4 --- hase-based interrogation SPR setup --- p.47 / Chapter 3.3.4.1 --- Michelson Interferometer --- p.48 / Chapter 3.3.4.2 --- Thehase-based setup --- p.49 / Chapter 3.3.5 --- Comparison and discussion of different configurations --- p.51 / Chapter 3.4 --- SPR experiment adopts wavelengths-based interrogation setup --- p.54 / Chapter 3.4.1 --- The experiment setup --- p.54 / Chapter 3.4.1.1 --- Samplereparation --- p.58 / Chapter 3.4.1.2 --- Experiment Result using 928 nm and 1120 nm initial resonant wavelength --- p.58 / Chapter 3.4.2 --- Experimental data analysis --- p.60 / Chapter 3.4.2.1 --- Conventional SPR data analysis --- p.61 / Chapter 3.4.2.1.1 --- Data analysis using minimum hunting witholynomial fit --- p.62 / Chapter 3.4.3 --- LS regression analysis for SPR data --- p.67 / Chapter 3.5 --- Session discussion and conclusion --- p.71 / Chapter 4 --- Near-Infrared Spectroscopy Experiment and Analysis / Chapter 4.1 --- Overview of near-infrared spectroscopy --- p.74 / Chapter 4.1.1 --- Electromagnetic spectrum --- p.75 / Chapter 4.1.2 --- Molecules vibration --- p.76 / Chapter 4.1.3 --- Law of absorption: Lambert-Beer Law --- p.77 / Chapter 4.2 --- Near Infrared Spectrometer --- p.79 / Chapter 4.2.1 --- Dispersive NIR spectrometer --- p.79 / Chapter 4.2.2 --- Fourier-Transformed NIR spectrometer --- p.83 / Chapter 4.2.3 --- Comparison between dispersive NIR and FT-NIR spectrometers --- p.85 / Chapter 4.2.4 --- Self-established monochromator based spectrometer --- p.87 / Chapter 4.2.4.1 --- Choose of detector andhotonic signal conversion unit --- p.90 / Chapter 4.3 --- Experimental result of NIR-spectrum by self-established spectrometer --- p.95 / Chapter 4.3.1 --- New approach for improving RMSEP without normalization of water spectrum as background information --- p.105 / Chapter 4.4 --- Experimental results of NIR-spectrum by commercial spectrometers --- p.109 / Chapter 4.5 --- Instrumentation limitation of NIR spectrometer --- p.117 / Chapter 4.6 --- Session Discussion and conclusion --- p.119 / Chapter 5 --- Conclusions and Suggestions for the Future Work / Chapter 5.1 --- Research aim and contributions --- p.126 / Chapter 5.2 --- Discussion on experiments --- p.128 / Chapter 5.3 --- Future work --- p.131 / Chapter 5.4 --- Conclusion --- p.134 / Reference: --- p.136 / Appendixes: --- p.141 / Appendix A Different approaches for non-invasive glucose measurement --- p.142 / Appendix B Calibration model of the SPR experimental result with 1120 nm as initial resonance wavelength --- p.145 / Appendix C Matlabrogram written for data analysis and simulation --- p.146 / Appendix D Detail specification of the monochromator using in our laboratory --- p.150 / Appendix E Monochromator Controlrogram --- p.156 / Appendix F The throughput example copied from the handbook of ORIEL Instruments --- p.165 / Appendix G RMSEPlot of the data obtained by self-established spectrometer with and without datare-treatments --- p.166 / "Appendix H RMSEPlot of the raw data obtained from the three different commercial machines (Vector-22N/C, NIRSystem 6500 and NIRSystem XDS) with and without datare-treatment" --- p.176
293

Resonance-enhanced laser-induced breakdown spectroscopy : how the beam profile of the ablation laser and the interception geometry and energy of the reheating laser affect analytical performance

Yip, Wing Lam 01 January 2009 (has links)
No description available.
294

Nuclear magnetic resonance studies of cellulose.

Maeno, Yuko January 1969 (has links)
No description available.
295

Investigation of molecular interactions with molecularly imprinted polymers

Myint, Mo Aung, n/a January 2009 (has links)
Currently, very little information is available for an in-depth understanding of the molecular binding interactions with molecularly imprinted polymers (MIPs). To address this issue MIPs that have high binding affinities for their template compounds were made so that the nature of these interactions could be elucidated using spectroscopic techniques. 12 functional MIPs were prepared using a series of azobenzene and anthracenyl derivatives as the templates. Affinities of these MIPs for the corresponding templates and analogues were determined by performing batch and competitive binding tests. It was found that extensively conjugated compounds that contain at least two OH groups, an electron-withdrawing substituent and have limited conformational freedom were effective templates. The most efficient MIP, M34, was prepared with 4-[(4-nitrophenyl)azo]-1,2-benzenediol (12). M34 exhibited high affinities for azobenzene derivatives of catechol, and bound those that did not contain non electron-withdrawing substituents more specifically. M34 did not lose affinity for 12 in the presence of analogues, and vice versa, in competitive binding tests. These observations suggested a distribution of different binding sites on M34. M34 bound substrates rapidly, which was attributed to its highly porous polymer matrix giving ready access to binding sites. Formation of the porous matrix was facilitated by the use of DMF as the porogen in the preparation of M34. DMF is not a conventional choice of porogen because use of such highly polar H-bonding solvents is thought to disrupt complexation between template and polymer precursors, which is required for the formation of binding sites. Significant changes in the wavenumbers and the intensities of absorption bands assigned to the catechol substructure of 12 were observed in the FT-Raman spectra of 12 bound to M34. These findings suggested that the catechol substructure was responsible for interactions of 12 with M34 that are critical to rebinding and imprinting. In-situ analyses of dithranol (8) being removed from and bound to its MIP, M23, were performed using ATR-IR spectroscopy. Only one band, assigned to the aromatic substructure of 8, was not obstructed by solvent bands in the spectra of unwashed M23 and washed M23 that was treated with the rebinding solution. The wavenumbers of the corresponding bands in the two spectra were significantly different. This observation suggested that there were differences in the vibrational characteristics of 8 bound to M23 under the two conditions. Evidence was found for H-bonding between OH groups of 8 and C=O group of methacrylic acid using transmission FT-IR spectroscopy. However, no evidence was found that showed significant interactions between 12 and 2-vinylpyridine. Methacrylic acid and 2-vinylpyridine were used as the functional monomers in the preparations of M23 and M34. The FT-IR spectra of mixtures of 12 and 4-vinylpyridine showed three new bands assigned to H-bonded OH stretches. These observations indicated that 4-vinylpyridine H-bonds with 12, and would be a more effective functional monomer than 2-vinylpyridine in the preparation of the MIPs for 12. Titration of 12 with 2-vinylpyridine was analysed by �H NMR spectroscopy. Only small changes to the signals of the corresponding compounds were observed. This lack of change was attributed to the use of d₇DMF, which would compete against 2-vinylpyridine for H-bonding interactions. The findings made using ATR-IR spectroscopy and FT-Raman were novel because previously reported data on bound templates obtained using the corresponding techniques did not show changes in the vibrational characteristics of templates as they bind to MIPs. This investigation has shown that rebinding and spectroscopic studies can provide information about the nature of the binding interactions in MIPs.
296

Baryon spectroscopy with FLIC fermions

Zanotti, James Michael. January 2002 (has links) (PDF)
"October 2002" Bibliography: p. 129-136. 1. Introduction -- 2. QCD and the standard model -- 3. The Lattice -- 4. Symanzik improvement in the Static Quark Potential -- 5. Scale determination for an improved Gluon Action -- 6. Fat-link Irrelevant Clover Fermion actions -- 7. Excited Baryons in Lattice QCD -- 8. Spin 3/2 Baryons -- 9. Conclusion. This thesis reports work done in conducting numerical simulations of Lattice QCD.
297

Excited state structures of polypyridyl complexes : a spectroscopic and DFT study

Howell, Sarah Louise, n/a January 2005 (has links)
This thesis reports the spectroscopic and computational studies of a number of Cu(I), Re(I) and Ru(II) complexes of polypyridyl ligands. The ligands considered in this study were 1,10-phenanthroline, 4,7-diphenyl-1,10-phenanthroline, 3,4,7,8-tetramethyl-1,10-phenanthroline, dibenzo[b,j][1,10]phenanthroline, dipyrido[2,3-a:3�,2�-c]phenazine, dipyrido[2,3-a:3�,2�-c]-6,7-dichlorophenazine and dipyrido[2,3-a:3�,2�-c]-6,7-dimethylphenazine. Density functional theory calculations were carried out on the polypyridyl ligands. Validation of the calculations was carried out by comparison of the predicted values to observables. The structures were compared to previously published X-ray crystal data. Calculated bond lengths were typically calculated to be within 0.02 Å of those in the crystal structure. The calculated vibrational spectra were compared to measured IR and Raman spectra. The correspondence between calculated and measured frequencies was quantified using the mean absolute deviation between the two sets of frequencies. This was typically found to be less than 10 cm⁻�. The robustness of the calculation was further tested by calculations on perdeuterated analogues of some of the ligands. The calculations were extended to metal moieties and validated as for the ligands. Resonance Raman and infrared spectra of the reduced states of some Re(I) complexes are reported. The structure and spectra have been modelled by considering the radical anion of the polypyridyl ligand and the reduced state of the complex. There is improvement in the mean absolute deviation, between calculated and observed frequencies, upon incorporation of the metal moiety into the calculation. Spectra are successfully modelled confirming the validity of the modelled structures. The resonance Raman and infrared spectra of the metal-to-ligand charge transfer excited states of some Cu(I), Re(I) and Ru(II) complexes are reported. Density functional theory calculations on the lowest energy triplet states aided in the spectral assignment of bands. Cu(I) complexes were successfully modelled with mean absolute deviations, between calculated and observed frequencies, of less than 10 cm⁻�. The spectra of the Re(I) and Ru(II) complexes were less successfully modelled. Incorporation of the Ru(II) centre into the calculation of the vibrational frequencies of dipyrido[2,3-a:3�,2�-c]phenazine complexes offers no improvement over modelling the radical anion of this polypyridyl ligand. The excited state lifetimes of a number of polypyridyl complexes have been reported. The changes in lifetimes of similar complexes were found to be consistent with the energy gap law or changes in the conjugation of the involved polypyridyl ligand. This project has allowed the excited state structures of a number of polypyridyl complexes to be determined using vibrational spectroscopy to validate density functional theory calculations. This has provided a study strategy that may be applied to other metal polypyridyl complexes.
298

Modelling and spectroscopy of polypyridyl and porphyrin complexes for electroluminescence and solar cell applications

Walsh, Penelope Jane, n/a January 2007 (has links)
This thesis reports the spectroscopic and computational studies of two classes of compounds, which have applications in new optoelectronic materials technology. Substituted ligands of dipyrido-[3,2a:2�,3�c]phenazine (dppz), and their Cu(I), Re(I) and Ru(II) complexes have utility in organic electroluminescent devices. A series of Zn(II) tetraphenylporphyrins with conjugated functional groups at the β-position have been used with success in liquid heterojunction dye-sensitized solar cells. The vibrational spectra and optoelectronic properties of the two classes were investigated using Raman, resonance Raman and transient resonance Raman spectroscopy, in conjunction with density functional theory methods. Density functional theory frequency calculations were used to aid vibrational mode assignments for the dppz compounds, and show close agreement with the experimental non-resonance Raman spectra. The enhancement of modes which are localized on differing sections of the ligand was identified. The nature of the absorbing chromophores for the dppz ligands and complexes was established using resonance Raman spectroscopy in concert with vibrational assignments from calculations. Transient resonance Raman spectra of the ligands provided spectral signatures for the triplet ligand-centred state; these features were observed in the TR� spectra of the metal complexes, along with other features attributable to MLCT states. Electroluminescent devices were fabricated using the dppz ligands and complexes as emissive dopants, and their properties investigated. The optoelectronic behaviour of the devices was found to be influenced by the mechanism of exciton formation on the dopant. The device properties were also dependent on the dopant concentration, the concentrations of other components and the driving voltage. The electronic structure of the porphyrin compounds was investigated using time-dependent density functional theory methods. Comparison of calculated optical transitions with experimental data shows that the calculations predict trends in the optical absorption spectra with change of functional group and with increase in conjugation chain length. The calculations suggest that the electron-withdrawing substituent decreases the configuration interaction effect by breaking the degeneracy of the two lowest unoccupied MOs, and other configuration interaction effects come into play involving other frontier MOs. Interrupting the conjugation of the functional group is shown to mitigate the breakdown of the configuration interaction. The perturbation of the normal electronic structure of the porphyrin by the substituent was also investigated using resonance Raman spectroscopy. Vibrational analysis identified bands due to the substituent, implying coupling between the porphyrin and substituent chromophores. Changes in frequency of porphyrin core modes due to the differing substituents and different metal centres were reproduced by density functional theory calculations. This project has allowed the spectroscopic investigation of the active optical states in a number of polypyridyl and porphyrin compounds, and determined the efficacy of DFT and TDDFT calculations to predict the properties of these compounds.
299

Baryon spectroscopy with FLIC fermions / James Zanotti.

Zanotti, James Michael January 2002 (has links)
"October 2002" / Bibliography: p. 129-136. / ix, 136 p. : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis reports work done in conducting numerical simulations of Lattice QCD. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics and Mathematical Physics, 2002
300

Use of the Richardson-Lucy algorithm in analyzing positron annihilation spectroscopy data /

Yu, Dapeng. January 2006 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2007. / Also available online.

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