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The saddle-shaped electron donor 9,10-his(l,3-dithiol-2-ylidene)-9,10-dihydroanthracene (TTFAQ) 49, which oxidises in a single, quasi-reversible, two-electron wave, accompanied by a dramatic conformational change, has been incorporated into donor-acceptor system 130. However, no significant charge-transfer interaction was observed. Pyrrolo-annelated TTFAQ derivatives 173 and 174 were synthesised, and donor-acceptor dyads, which showed intramolecular charge-transfer interactions, derived. TTFAQ cyclophanes 206 and 207 were synthesised in good yields, paving the way for the incorporation of more elaborate functionalities into TTFAQ cyclophanes, as exemplified by the synthesis of a TTFAQ- phenanthroline cyclophane with potential use as an electroactive sensor. A new methodology for the synthesis of TTFAQ derivatives has been developed, allowing the synthesis of cyanoethyl protected TTFAQ thiolate derivatives. These derivatives afforded several TTFAQ cyclophanes, of which the most interesting were the double-bridged cyclophanes 291 and 292. Due to the rigidity imposed by the two bridges, little conformational change is possible upon oxidation, which for the first time allowed us to study the elusive TTFAQ cation radical using cyclic voltammetry and spectroelectrochemistry, since 291 and 292 are oxidised in two, reversible, one-electron waves. The X-ray crystal structures of numerous new TTFAQ derivatives are also presented.

The search for a detailed understanding of the mechanism of zeolite synthesis has, over the past two decades, promoted many investigations into the species present in (alumino)silicate solutions. It is generally accepted that dissolved (alumino)silicate species are involved as precursors in the nucleation of zeolites. Several techniques have been employed to understand the mechanism of formation of these complex structures. NMR spectroscopy has been shown to be a very powerful tool for the detection and characterization of (alumino)silicate species in the solutions in question. This thesis presents a comprehensive study of certain silicate solutions employmg (^29)Si NMR which has extended the knowledge gained in previous studies. The role of structure-direction on the distribution of silicate species in silicate solutions is discussed, the results providing more understanding of this effect. The effects of pH, temperature, Si/cation ratio and silica concentration on the distribution of silicate anions were also studied.Aluminium-27 NMR was applied to investigate the local structure about alummium atoms in a series of alumino silicate solutions with Si:Al mole ratios pertinent to zeolite synthesis. The kinetics of the reaction of aluminate with silicate anions have been studied by investigating the temporal evolutions of (^29)Al NMR spectra and by 2D NMR exchange spectroscopy. Structural analyses of two new silicate crystals were carried out by single-crystal X-ray diffraction. Liquid- and solid-state NMR spectroscopy were employed to characterize the mother liquors, the powdered polycrystalline products, and their melts.The Zeolite SUZ-9 was characterized by application of multinuclear magnetic resonance spectroscopy : (^29)Si, (^27)Al, (^13)C and (^1)H NMR spectra of this zeolite were studied.

by Chan Kwok Kwan. / Chinese title: / Thesis (M.Phil.) -- Chinese University of Hong Kong, 1983

by Choy Wing Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 115-121). / DESCRIPTIVE NOTE --- p.iii / ACKNOWLEDGEMENTS --- p.v / Chapter CHAPTER ONE: --- BRIEF REVIEW OF THE WATR-CPMG AND OTHER SOLVENT SUPPRESSION METHODS --- p.1 / Chapter 1.0 --- Introduction --- p.1 / Chapter 1.1 --- Some Common Solvent Suppression Techniques --- p.2 / Chapter 1.1.1 --- Brief Summary of Some Common Solvent Suppression Techniques --- p.2 / Chapter 1.1.2 --- Criteria for the Evaluation of Solvent Suppression Methods --- p.8 / Chapter 1.2 --- Application of the WATR-CPMG Method in Solvent Suppression --- p.10 / Chapter 1.2.1 --- The CPMG Pulse Sequence --- p.10 / Chapter 1.2.2 --- The Theory of Solvent Suppression by WATR Method --- p.12 / Chapter 1.3 --- Scope of this Thesis --- p.15 / Chapter CHAPTER TWO: --- OPTIMIZATION OF WATR-CPMG PARAMETERS FOR QUANTITATIVE ANALYSIS IN DILUTE AQUEOUS SOLUTION --- p.19 / Chapter 2.1 --- Investigation of the WATR-CPMG Parameters --- p.19 / Chapter 2.1.1 --- Use of Ammonium Chloride as Proton Exchange Reagent --- p.19 / Chapter 2.1.2 --- The pH Dependence of the Proton Exchange Process --- p.21 / Chapter 2.1.3 --- Relaxation Delay Time --- p.27 / Chapter 2.1.4 --- Measurement of T1 of Protons In Aqueous Solution --- p.31 / Chapter 2.1.5 --- The position of the Carrier Frequency --- p.41 / Chapter 2.1.6 --- Modelling of the Off-Resonance Effect --- p.46 / Chapter 2.1.7 --- The Tau Value Used in the WATR-CPMG Method --- p.51 / Chapter 2.2 --- The Setting of Acquisition Parameters and Data Processing --- p.57 / Chapter 2.2.1 --- Digital Resolution and Spectral Width --- p.57 / Chapter 2.2.2 --- The Setting of Receiver Gain --- p.60 / Chapter 2.3 --- Summary --- p.61 / Chapter CHAPTER THREE: --- APPLICATION OF THE WATR-CPMG METHOD TO THE QUANTITATIVE ANALYSIS OF GLUCOSE IN BLOOD PLASMA AND DILUTE AQUEOUS SOLUTION --- p.62 / Chapter 3.0 --- Introduction --- p.62 / Chapter 3.1 --- Experimental Section --- p.62 / Chapter 3.1.1 --- Characterization of the Metabolites in Blood Plasma --- p.62 / Chapter 3.1.2 --- Reagents --- p.66 / Chapter 3.1.3 --- Solution Preparations --- p.66 / Chapter 3.1.4 --- Measurement of Plasma Glucose by Glucose Oxidase Method --- p.67 / Chapter 3.1.5 --- NMR Measurement --- p.68 / Chapter 3.1.6 --- HPLC Measurement --- p.78 / Chapter 3.2 --- Results and Discussion --- p.79 / Chapter 3.2.1 --- Analysis of Results --- p.79 / Chapter 3.2.2 --- Discussion --- p.84 / Chapter 3.2.3 --- Conclusion --- p.85 / Chapter CHAPTER FOUR: --- HOMODECOUPLED WATR-CPMG METHOD --- p.86 / Chapter 4.0 --- Introduction --- p.86 / Chapter 4.1 --- Application of Combined Time Sharing Homodecoupling WATR-CPMG Method for Quantitative Analysis in Aqueous Solution --- p.87 / Chapter 4.1.1 --- The Time Sharing Homonuclear Decoupling and Average Hamiltonian Theory --- p.87 / Chapter 4.1.2 --- Homodecoupling in Aqueous Solution --- p.89 / Chapter 4.2 --- Experimental --- p.90 / Chapter 4.2.1 --- The Preliminary Investigation --- p.90 / Chapter 4.2.2 --- Homodecoupl ing in 30%D20/70%D20 Solution --- p.97 / Chapter 4.2.3 --- Homodecoupling-CPMG (HDCPMG) in Quantitative Analysis --- p.102 / Chapter 4.3 --- Conclusion --- p.110 / Chapter CHAPTER FIVE: --- CONCLUSION --- p.113 / BIBLIOGRAPHY --- p.115 / APPENDIX I The Computer Simulation of the Off-Resonance Effect on the Water Signal Suppression --- p.122 / APPENDIX II The Computer Simulation Program --- p.125 / APPENDIX III The Simulation Data --- p.129

Siu Man Hin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract --- p.i / Abstract in Chinese --- p.iv / Acknowledgement --- p.vi / Content --- p.vii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Protein folding - Coil-to-globule transition --- p.1 / Chapter 1.2 --- Quaternary structure of proteins - Aggregation --- p.5 / Chapter 1.3 --- The effect of fast and slow heating rate to the aggregation of copolymers --- p.11 / Chapter 1.4 --- Main goal in thesis --- p.14 / Chapter 1.5 --- References --- p.18 / Chapter Chapter 2 --- Fundamentals of light scattering and instrumentation / Chapter 2.1 --- Static laser light scattering --- p.21 / Chapter 2.2 --- Dynamic light scattering --- p.22 / Chapter 2.3 --- Correlation function profile analysis --- p.24 / Chapter 2.4 --- Molar mass distribution and conformation of polymers --- p.25 / Chapter 2.5 --- Instrumentation / Chapter 2.5.1 --- Light source --- p.27 / Chapter 2.5.2 --- Cell design --- p.28 / Chapter 2.5.3 --- Detector --- p.28 / Chapter 2.5.4 --- Differential refractometer --- p.29 / References --- p.30 / Chapter Chapter 3 --- The effect of comonomer distribution on the coil-to-globule transition of a single AB copolymer chain in dilute solution / Chapter 3.1 --- Introduction --- p.32 / Chapter 3.2 --- Experimental / Chapter 3.2.1 --- Sample preparation and characterization --- p.35 / Chapter 3.2.2 --- Differential Scanning Calorimeter --- p.37 / Chapter 3.3 --- Results and discussion --- p.38 / Chapter 3.4 --- References --- p.49 / Chapter Chapter 4 --- Formation of mesoglobular phase of amphiphilic copolymer chains in dilute solution: 1. Effect of comonomer distribution / Chapter 4.1 --- Introduction --- p.50 / Chapter 4.2 --- Sample preparation and characterization --- p.53 / Chapter 4.3 --- Results and discussion --- p.54 / Chapter 4.4 --- References --- p.65 / Chapter Chapter 5 --- Formation of mesoglobular phase of amphiphilic copolymer chains in dilute solution: 2. Effect of comonomer distribution / Chapter 5.1 --- Introduction --- p.66 / Chapter 5.2 --- Sample preparation and characterization --- p.69 / Chapter 5.3 --- Results and discussion --- p.71 / Chapter 4.4 --- References --- p.80

Abstract