Thesis (Ph. D.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.

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Capillary electrochromatography (CEC) is a rapidly developing liquid chromatographic technique in which electroosmotic flow (EOF) is used to propel mobile phase through the chromatographic column. The use of EOF results in reduced band dispersion when compared with pressurised flow, but narrow capillaries are required to avoid dispersion due to heating that arises from the required application of high electrical potentials. Measurement of UV absorbance in these narrow capillaries is therefore relatively insensitive, demanding improved detection methods. This work presents an alternative strategy that is based on the combination of ion trap accumulation with time-of-flight mass spectrometry. Electrospray is most often used to transfer analytes from solution to the gas phase, concomitant with ionisation, when interfacing CEC to mass spectrometry. The small volumetric flow rates encountered in CEC, however, raise the possibility of other types of interface being effective. The work presented here describes the development of a novel interface in which a pulsed IR laser is used to vaporise chromatographic eluent, followed by ionisation using a pulsed UV laser. Vaporisation and ionisation both occur within the ion trap to remove the possibility of transmission losses. Ionisation laser wavelength is varied to impart a degree of selectivity. The presence of vaporised solvent and analyte ions inside the trap offers the possibility of performing ion-molecule chemistry. In developing this instrument, the electrochromatographic column was separated from the interface by an electrically grounded junction and a transfer capillary. To preserve chromatographic efficiency, the fluid dynamics of this junction between the column and the transfer capillary were investigated both computationally and experimentally. Simulations of the fluid dynamics of the junction are presented. In order to test the interface without the intermittent, chromatographic, delivery of analyte, a continuous leak inlet was employed. The performance of the instrument was evaluated with polycyclic aromatic hydrocarbons because they are important environmental pollutants and because they are amenable to laser ionisation at 266 nm. Expressed as a number of theoretical plates per metre, an average chromatographic efficiency of 95,000 was obtained with a test mixture that consisted of acenaphthene, biphenyl, fluorene, naphthalene and phenanthrene. Furthermore, using the leak inlet, naphthalene was detected as a 100 nM solution in acetonitrile.

Beyond the expected DBP exposure from drinking water, dermal from bathing, and inhalation, occurrence in food and beverage items can provide an additional occurrence pathway. Synthetic dyes are often added to beverages for aesthetic purposes and many are in the form of a reactive azo (-N=N-) dye or triarylmethane dye, both with a characteristic aromatic ring. The presence of dyes in beverages that are reconstituted with disinfected tap water pose the risk of reactions with the residual chlorine in the drinking water resulting in decolorization, and of greater concern, disinfection byproduct formation. Additionally, oral over-the-counter (OTC) medications contain chemical constituents that when reconstituted with tap water present a risk of DBP formation. Several studies were performed to evaluate the kinetic decay rates of the dyes and drugs in disinfectants, and the effects of water quality conditions on DBP formation. Commercial beverage products and OTC medications were evaluated for the DBPs that were detected in the free chlorine-treated precursor samples. The dye and drugs precursors followed second order kinetics, with the fastest rates for brilliant blue and phenylephrine in chlorinated water. The effects of water properties on precursor degradation and DBP formation was complex due to the influence of characteristics of precursor molecules. The cytotoxic and anti-estrogenic responses were measured in the dye and drug precursors and their respective beverages and OTC medications, to determine potential links. Mio Energy showed estrogenic character and Alka Seltzer induced an anti-estrogenic and cytotoxic response, however there were no clear linkages between the beverage/ medication and their respective dye and drug precursors.

Kam Yuen Kwan = 利用散射及反衝粒子飛行時間譜儀及其他表面分析儀器就LiTaO3對質子及鋰離子交換後改變之研究 / 甘婉君. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Kam Yuen Kwan = Li yong san she ji fan chong li zi fei xing shi jian pu yi ji qi ta biao mian fen xi yi qi jiu LiTaO3 dui zhi zi ji li li zi jiao huan hou gai bian zhi yan jiu / Gan Wanjun. / Acknowledgements --- p.i / Abstract --- p.iii / Table of contents --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Definition of Ferroelectrics --- p.1 / Chapter 1.2 --- Common Properties of Ferroelectrics --- p.2 / Chapter 1.3 --- Polarization --- p.2 / Chapter 1.4 --- Lithium Tantalate (LiTa03) --- p.7 / Chapter 1.4.1 --- Crystal Structure --- p.8 / Chapter 1.4.2 --- Pyroelectric Effect --- p.9 / Chapter 1.4.3 --- Determination of Polarity --- p.10 / Chapter 1.4.4 --- Proton Exchange --- p.11 / Chapter 1.4.5 --- Reverse Exchange --- p.12 / Chapter 1.4.6 --- Applications --- p.13 / Chapter 1.5 --- Emerging Attentions in Surface Properties of Smart Materials --- p.14 / Chapter 1.6 --- Difficulties in Surface Studies of Ferroelectric and Related Smart Materials --- p.15 / Chapter 1.7 --- Recent Developments of TOF-SARS in Our Research Group and Its Applicability on LiTa〇3 --- p.16 / Chapter 1.8 --- Objectives of the Present Thesis Work --- p.17 / Chapter 1.9 --- Organization of the Thesis --- p.17 / Chapter 1.10 --- Reference --- p.18 / Chapter Chapter 2 --- Ion Exchange Processes and Sample Prepartion --- p.20 / Chapter 2.1 --- Fundamental of Ion Exchange Technique --- p.20 / Chapter 2.2 --- Sample Preparation --- p.22 / Chapter 2.2.1 --- Starting Material --- p.22 / Chapter 2.2.2 --- Proton Exchange Procedures --- p.23 / Chapter 2.2.3 --- Reverse Exchange Procedures --- p.23 / Chapter 2.3 --- Reference --- p.24 / Chapter Chapter 3 --- Time-of-Flight Ion Scattering and Recoiling Spectrometry (TOF-SARS) --- p.26 / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.1.1 --- Physics in Elemental Analysis --- p.26 / Chapter 3.1.2 --- Physics in Structural Analysis --- p.29 / Chapter 3.2 --- Instrumentation --- p.32 / Chapter 3.2.1 --- Vacuum Chamber --- p.33 / Chapter 3.2.2 --- Pumping System --- p.35 / Chapter 3.2.3 --- Sample Manipulator --- p.35 / Chapter 3.2.4 --- Pulsed Ion Beam Line --- p.36 / Chapter 3.2.5 --- Detectors and Associated Electronics --- p.37 / Chapter 3.3 --- Reference --- p.39 / Chapter Chapter 4 --- Other Surface Science Tools Used in This Work --- p.41 / Chapter 4.1 --- Fourier Transform Infrared Spectroscopy (FTIR) --- p.41 / Chapter 4.1.1 --- Principle of FTIR --- p.41 / Chapter 4.1.2 --- Experiment --- p.42 / Chapter 4.1.3 --- Attenuated Total Reflectance (ATR) Mode of FTIR --- p.44 / Chapter 4.2 --- X-Ray Photoelectron Spectroscopy (XPS) --- p.45 / Chapter 4.2.1 --- Basic Principle of XPS --- p.45 / Chapter 4.2.2 --- Experimental Set Up --- p.48 / Chapter 4.3 --- Elastic Recoil Detection (ERD) --- p.49 / Chapter 4.3.1 --- Basic Theory of ERD --- p.49 / Chapter 4.3.2 --- Experimental Set Up --- p.50 / Chapter 4.4 --- Scanning Electron Microscope (SEM) --- p.51 / Chapter 4.4.1 --- Working Principle of SEM --- p.52 / Chapter 4.4.2 --- Experimental Set Up --- p.52 / Chapter 4.5 --- Reference --- p.53 / Chapter Chapter 5 --- Results and Discussions --- p.54 / Chapter 5.1 --- ERD Results on Incorporation of Protons --- p.54 / Chapter 5.2 --- XPS Results on Proton Exchange and Reverse Exchange --- p.56 / Chapter 5.3 --- FTIR Results on Proton Exchange and Reverse Exchange --- p.57 / Chapter 5.4 --- SEM Results on Domain-Inversion Induced by Proton Exchange --- p.59 / Chapter 5.5 --- TOF-SARS Results on Enhancement of Ion-induced Electron Emission by Proton Exchange --- p.61 / Chapter 5.5.1 --- Typical TOF-SARS Spectra - Data from Molybdenum Sample (Mo) Holder --- p.61 / Chapter 5.5.2 --- Virgin LiTa03 (0001) --- p.62 / Chapter 5.5.3 --- Possible Mechanism for the Variation of O(S) and the Electron Emission Yield --- p.65 / Chapter 5.5.4 --- The Use of O(S) Peak to Calculate the Potential Built Up upon a Change of Temperature --- p.67 / Chapter 5.5.5 --- TOF-SARS Data from the Proton and Lithium-ion Exchanged LiTa03 (0001) --- p.69 / Chapter 5.5.6 --- Plausible Mechanisms of Enhancement of Ion-induced Electron Yield induced by Proton Exchange --- p.70 / Chapter 5.6 --- Additional Discussions of the TOF-SARS Data on LiTa03 and Other Relevant Experiments --- p.75 / Chapter 5.6.1 --- Additional Discussion of the Nature of the Electron Peaks --- p.75 / Chapter 5.6.2 --- Additional Experiments on Azimuthal Angle (δ) Scans --- p.77 / Chapter 5.6.2.1 --- Data from Platinum (Pt) (111) as a Reference Test --- p.77 / Chapter 5.6.2.2 --- Azimuthal Angle Dependence of Ion-induced Electron Emission from Proton-ion Exchanged LiTa03 (0001) --- p.78 / Chapter 5.7 --- Reference --- p.80 / Chapter Chapter 6 --- Conclusion --- p.83 / Chapter Chapter 7 --- Appendix --- p.86 / Chapter 7.1 --- Caption --- p.86 / Chapter 7.2 --- Figures --- p.90

Leang Po Shan = 利用飛行時間散射反衝符號測量譜儀研究LiTaO3(001)單晶之表面電荷動態特性 / 梁寶珊. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 50-51). / Text in English; abstracts in English and Chinese. / Leang Po Shan = Li yong fei xing shi jian san she fan chong fu hao ce liang pu yi yan jiu LiTaO3(001) dan jing zhi biao mian dian he dong tai te xing / Liang Baoshan. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Ferroelectricity and pyroelectricity of LiTαO3 --- p.1 / Chapter 1.2 --- Surface Studies of Ferroelectrics --- p.5 / Chapter 1.2.1 --- Size Effect and Importantce of Surface Properties --- p.5 / Chapter 1.2.2 --- General Difficulties in Surface Studies of Ferroelectrics --- p.5 / Chapter 1.2.3 --- Applicability of TOF-SARS in the Analysis of Ferro- electrics --- p.6 / Chapter 1.3 --- Surface Charge Dynamics on Ferroelectrics --- p.7 / Chapter 1.3.1 --- Surface Charge Screening of Spontaneous Polarization --- p.7 / Chapter 1.3.2 --- Discharge of Excessive Surface Charge --- p.7 / Chapter 1.4 --- Objectives of the Thesis Work: TOF-SARS Study of Surface Charge Dynamics of LiTαO3 --- p.11 / Chapter 2 --- Ion-Surface Interaction --- p.13 / Chapter 3 --- Time-of-Flight (TOF) Ion Scattering and Recoiling Spectrom- eter --- p.17 / Chapter 3.1 --- TOF Ion Scattering and Recoiling Spectrometer --- p.18 / Chapter 3.2 --- Ion Column --- p.19 / Chapter 3.2.1 --- Ion Source --- p.19 / Chapter 3.2.2 --- Pulsing System --- p.19 / Chapter 3.2.3 --- ExB Wien Filter Mass Analyzer --- p.20 / Chapter 3.2.4 --- Einzel Lens --- p.20 / Chapter 3.2.5 --- Neutral Beam Trap --- p.20 / Chapter 3.2.6 --- Vacuum Chamber and Manipulator --- p.20 / Chapter 3.3 --- Variable Angle Detector --- p.23 / Chapter 3.3.1 --- Setup --- p.23 / Chapter 3.3.2 --- Beam Alignment --- p.24 / Chapter 4 --- Results and Analysis --- p.25 / Chapter 5 --- Study of Charge Relaxation Process --- p.35 / Chapter 5.1 --- Derivation of Surface Electric Potential --- p.35 / Chapter 5.2 --- Data Analysis --- p.40 / Chapter 6 --- Conclusion --- p.49 / Bibliography --- p.50

Li, Gang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 102-108). / Abstracts in English and Chinese. / TABLE OF CONTENTS --- p.v / LIST OF FIGURES --- p.viii / LIST OF TABLES --- p.xi / ABBREVIATIONS --- p.xii / Chapter Chapter One --- Introduction / Chapter 1.1 --- Matrix-assisted Laser Desorption/Ionization (MALDI) --- p.2 / Chapter 1.1.1 --- Laser Desorption --- p.2 / Chapter 1.1.2 --- Matrix-assisted Laser Desorption/Ionization --- p.2 / Chapter 1.2 --- Time-of-flight Mass Spectrometry --- p.6 / Chapter 1.2.1 --- Linear Time-of-flight Mass Spectrometer --- p.6 / Chapter 1.2.2 --- Reflectron Time-of-flight Mass Spectrometer --- p.7 / Chapter 1.2.2.1 --- Linear-field Reflectron --- p.9 / Chapter 1.2.2.2 --- Nonlinear-field Reflectron --- p.12 / Chapter 1.3 --- Structural Analysis Using Time-of-flight Mass Spectrometer --- p.13 / Chapter 1.4 --- Project Objectives --- p.17 / Chapter Chapter Two --- Instrumentation and Experimental / Chapter 2.1 --- Instrumentation --- p.20 / Chapter 2.1.1 --- Laser system --- p.20 / Chapter 2.1.2 --- Flight Tube and Vacuum System --- p.20 / Chapter 2.1.3 --- Ion source --- p.22 / Chapter 2.1.4 --- Deflector and Time Ion Selector --- p.24 / Chapter 2.1.5 --- Two-stage Gridless Reflectron --- p.28 / Chapter 2.1.6 --- "Detectors, Digitizer and Computer System" --- p.28 / Chapter 2.2 --- Experimental --- p.31 / Chapter 2.2.1 --- Sample preparation --- p.32 / Chapter 2.2.2 --- PSD calibration --- p.32 / Chapter Chapter Three --- "Simulation Studies of Time Ion Selector, Collision cells and Curved-field Reflectron" / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Time Ion selector --- p.37 / Chapter 3.3 --- Collision cell --- p.46 / Chapter 3.3.1 --- Simulation of Collision Induced Dissociation (CID) Conditions --- p.46 / Chapter 3.3.2 --- Design and Performance Evaluation of Different Collision Cells --- p.48 / Chapter 3.4 --- Curved-field reflectron (CFR) --- p.58 / Chapter 3.4.1 --- Introduction --- p.58 / Chapter 3.4.2 --- Derivation of Analytical Equations --- p.58 / Chapter 3.4.3 --- Effect of Floating Potential of the Collision Cell --- p.65 / Chapter 3.4.4 --- Effect of R and θ Parameters --- p.65 / Chapter 3.4.5 --- Effect of Length of the Reflectron --- p.70 / Chapter 3.5 --- Conclusions --- p.73 / Chapter Chapter Four --- Construction and Performance Evaluation of Modified Time-of-flight Mass Spectrometer / Chapter 4.1 --- Benchmark Results for the Origin Reflectron Time-of-flight Mass Spectrometer --- p.75 / Chapter 4.2 --- Hardware Modifications of Reflectron Time-of-flight Mass Spectrometer --- p.75 / Chapter 4.2.1 --- Collision Cell --- p.75 / Chapter 4.2.2 --- Curved-field Reflectron --- p.79 / Chapter 4.3 --- Evaluation of the Curved-field Reflectron --- p.81 / Chapter 4.4 --- Evaluation of the field-shaped cylindrical collision cell --- p.85 / Chapter 4.5 --- Conclusions --- p.95 / Chapter Chapter Five --- Concluding Remarks / Chapter 5.1 --- Concluding Remarks --- p.100 / References --- p.101 / Appendix / Appendix 1 User program for time ion selection --- p.108 / Appendix 2 User program for gas collision --- p.111 / Appendix 3 MATHEMATICA program used in calculation for curved-fleld reflectron --- p.114

Isotachophoresis (ITP) coupled to capillary zone electrophoresis (CE) in a comprehensive manner was used to separate mixture components in both insufficient and sufficient concentrations without heart-cutting or splitting. Examples of comprehensive ITP-CE involving multiple CE injections of preconcentrated ITP zones are demonstrated. In the comprehensive arrangement, all of the sample in the first dimension (ITP) is subjected to analysis in the second dimension (CE), without significant sample loss or decrease in sample detectability resulting from removal of a portion of the sample. This is especially important for analytes at low concentrations which may form a single mixed zone instead of individual ITP zones. Direct online coupling of ITP to CE in this comprehensive arrangement involved the use of columns having different diameters with one directly inserted inside the other. A counterflow was applied when the isotachophoretic sample stack reached the bifurcation point. Large volume (10 µL) injections were made using an electrically-insulated commercial polymeric rotary valve injector for increased reproducibility compared to previous comprehensive ITP-CE studies, with ITP and CE retention time RSD values ranging from 2-5%. An ultraviolet (UV) detector positioned at the bifurcation point was used to determine the beginning of CE injection. Application of a splitting voltage at the bifurcation point showed no affect on analyte transfer into the CE column. By using multiple injections of the ITP band(s), CE column overloading was not observed. Online capillary isotachophoresis (ITP) and comprehensive isotachophoresis-capillary electrophoresis (ITP-CE) were also coupled with electrospray ionization (ESI)-orthogonal acceleration time-of-flight mass spectrometry (TOFMS). Separations were performed using 200 µm I.D. and 50 µM I.D. polyvinylalcohol (PVA)-coated fused silica capillaries for ITP and CE, respectively. Both ITP and ITP-CE were coupled to TOFMS for analysis of sufficient (10-5 M) and insufficient (10-6-10-7 M) concentrations of angiotensins in mixtures. ITP-TOFMS of a single mixed zone of five angiotensins (3 x 10-7 M) showed that ion suppression due to the co-elution of angiotensin III in the electrospray significantly reduced the ionization of other analytes. A practical solution to the detection difficulties for ITP mixed zones involved the insertion of a CE separation between the ITP and TOFMS for online preconcentration, separation, and identification in one system.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants and are mostly products of the incomplete combustion of organic material. PAHs are often found in environmental samples as a complex mixture of isomers. In addition, the same sources that produce complex PAH mixtures also produce other poorly characterized mixtures of organic compounds, commonly referred to as an unresolved complex mixture (UCM), that act as matrix interferences in the chromatographic analysis of samples. Conventional one-dimensional chromatographic techniques, such as gas chromatography coupled to mass spectrometry (GC/MS), are not sufficient for the analysis and quantitation of complex PAH mixtures present in environmental samples due to the high degree of overlap in compound vapor pressures, boiling points, and mass spectral fragmentation patterns. Therefore, the separation and quantitation of complex mixtures of individual PAH compounds in environmental samples requires high chromatographic resolution. Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC��GC/ToF-MS) was used for this study. GC��GC/ToF-MS uses two different gas chromatographic columns, with different separation mechanisms, for the analysis of complex environmental samples. In theory, the peak capacity in GC��GC/ToF-MS is equivalent to the product of the individual peak capacities of each column used. However, in practice, this is rarely obtained because of the existing correlation between the two GC columns used. This dissertation is a compilation of three studies related to analytical method development for the identification and quantitation of complex PAH mixtures (including parent-PAHs, alkyl-PAHs, oxy-PAHs, nitro-PAHs, thio-PAHs, chloro-PAHs, bromo-PAHs and PAHs with molecular weight higher than 300 Da) that may be present in environmental samples using novel column combinations in GC��GC/ToF-MS. The use of a liquid crystal column (LC-50) in the first dimension, followed by a nano-stationary phase column (NSP-35) in the second dimension, was evaluated for the separation of a standard PAH mixture containing 97 different PAHs. Two standard reference materials purchased from NIST (NIST SRM1650b ��� Diesel Particulate Matter and NIST SRM1975 ��� Diesel Extract) were used, after extraction and cleanup, for method validation and comparison between the commonly used non-polar �� polar column combination and the LC-50 �� NSP-35 column combination with high orthogonality. As part of the method validation, an aliquot of NIST SRM1975 (Diesel extract), without sample cleanup was also analyzed for PAHs, showing that the LC-50 �� NSP-35 column combination was accurate (with an average absolute percent difference of approximately 30%) for the identification and quantitation of complex PAH mixtures in environmental samples, with reduced sample preparation prior to analysis. In addition, the LC-50 �� NSP-35 column combination was used for the analysis of PAHs sorbed to polystyrene pellets deployed in an urban bay area as passive water samplers because one-dimensional GC/MS was ineffective due to the presence of a strong unresolved complex mixture (UCM) and matrix interferences. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Dec. 27, 2012 - June 27, 2013

A method for the oxidation of lipoproteins in vitro was developed using the free radical initiator, 2,2?-azobis-(2-amidinopropane) dihydrochloride (AAPH). Following in vitro oxidation, the susceptibility to oxidation of the serum samples was studied using density gradient ultracentifugation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Shifts in mean buoyant density of the lipoprotein particles, specifically low density lipoprotein (LDL) and high density lipoprotein (HDL), were observed in the density profile following centrifugation. The degree of shift in the density proved to be proportional to the extent of oxidation. Changes in apolipoproteins were studied with MALDI-TOF-MS. Observed variations in the mass spectra include m/z shifts due to chemical modifications and change in isoform distributions. The oxidation procedure and analysis techniques were applied to a clinical application to study the effects of table grape consumption on lipoprotein susceptibility to oxidation. The main objective of the research, to show feasibility that these methods could be used in a clinical setting, was achieved.