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A cryogenic detector for submillimetre astronomyGom, Bradley Gustav, University of Lethbridge. Faculty of Arts and Science January 1999 (has links)
Over the last several years, a submillimetre astronomical polarizing Fourier Transform Spectrometer (FTS) has been developed for use at the James Clerk Maxwell Telescope (JCMT) located atop Mauna Kea, Hawaii. A new liquid3 He cooled dual polarization detector system has been carefully designed for use with this FTS to eliminate noise problems encountered with UKT14, the JCMT facility bolometric detector. The objective of this thesis is to evaluate and optimize the performance of the new detector system. The design of the detector system is discussed, and the noise performance of the system is evaluated. The system performance is determined from photmetric, classical B-I, and spectroscopic measurements. Compared to UKT14, the intrinsic bolometer noise is reduced by a factor of - 2. More importantly, the spectral signal to noise ratio is improved by a factor of - 10 due to the elimination of electrical pickup and microphone noise in the detector signal. / xiv, 156 leaves : ill. ; 28 cm.
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Study of chemically modified food proteins by vibrationalspectroscopyWong, Hing-wan., 王慶雲. January 2006 (has links)
published_or_final_version / abstract / Botany / Doctoral / Doctor of Philosophy
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Development of new methods to perform matrix-assisted laser desorption/ionization (MALDI) experiments in fourier-transform ion-cyclotron-resonance mass spectrometer (FTICR-MS). / CUHK electronic theses & dissertations collectionJanuary 2000 (has links)
Sze Tung Po Eric. / "Mar 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
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Sustained off-resonance irradiation collision-induced dissociation of peptide ions in a fourier transform ion-cyclotron-resonance mass spectrometer.January 2003 (has links)
Duan Lifang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 83-87). / Abstracts in English and Chinese. / Title Page --- p.i / Abstract (English) --- p.ii / Abstract (Chinese) --- p.iii / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Tables --- p.vii / List of Figures --- p.viii / Symbols and Abbreviations --- p.x / Chapter CHAPTER 1 --- INTRODUCTION / Chapter 1.1 --- Mass spectrometry in biochemistry --- p.1 / Chapter 1.2 --- Electrospray ionization (ESI) --- p.2 / Chapter 1.3 --- Fourier transforms ion cyclotron resonance mass spectrometry (FTICR-MS) --- p.4 / Chapter 1.3.1 --- Ion motions --- p.5 / Chapter 1.3.2 --- Mass calibration --- p.7 / Chapter 1.3.3 --- Tandem mass spectrometry --- p.11 / Chapter 1.4 --- Sustained off-resonance irradiation collision-induced dissociation (SORI-CID) of peptide ions --- p.13 / Chapter 1.5 --- Outline of present work --- p.18 / Chapter CHAPTER 2 --- INSTRUMENTATION AND EXPERIMENTAL / Chapter 2.1 --- Fourier-trans form ion cyclotron resonance mass spectrometer --- p.19 / Chapter 2.1.1 --- Vacuum system --- p.19 / Chapter 2.1.2 --- Nanospray source --- p.23 / Chapter 2.1.3 --- Ion transfer system --- p.26 / Chapter 2.1.4 --- Infinity cell --- p.28 / Chapter 2.1.5 --- Data acquisition system --- p.29 / Chapter 2.2 --- Experimental --- p.29 / Chapter 2.2.1 --- Simple acquisition pulse program --- p.30 / Chapter 2.2.2 --- Tandem mass spectrometry (SORI-CID MS/MS) --- p.32 / Chapter CHAPTER 3 --- DISSOCIATION OF MODEL PEPTIDE IONS UNDER SORI-CID CONDITIONS / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Experimental --- p.37 / Chapter 3.3 --- Results and discussion --- p.41 / Chapter 3.3.1 --- "SORI-CID of XG3WG3X (where X 二 R, K and N)" --- p.41 / Chapter 3.3.2 --- SORI-CID of RGnWGnR (where n=l -5) --- p.46 / Chapter 3.3.3 --- SORI-CID of RG3XG3R (where X = D and E) --- p.48 / Chapter 3.4.4 --- SORI-CID of sequence isomers of RG5WG5R --- p.51 / Chapter 3.4 --- Conclusions --- p.56 / Chapter CHAPTER 4 --- EXACT MASS MEASUREMENTS OF THE PRODUCT IONS DERIVED FROM SORI-CID FTICR-MS / Chapter 4.1 --- Introduction --- p.57 / Chapter 4.2 --- Experimental --- p.60 / Chapter 4.3 --- Results and discussion --- p.61 / Chapter 4.3.1 --- Origin(s) of the mass measurement error --- p.63 / Chapter 4.3.2 --- Pressure effect on the cyclotron frequencies of trapped ions --- p.67 / Chapter 4.3.3 --- Modified internal lock-mass calibration method --- p.70 / Chapter 4.4 --- Conclusions --- p.79 / Chapter CHAPTER 5 --- CONCLUSIONS --- p.81 / REFERENCES --- p.83 / APPENDIX I The Proton affinity (PA) and the structural formulae of 20 α-amino acids --- p.88 / APPENDIX II Schematics of the proposed mechanisms of peptide dissociation under low-energy CID conditions --- p.89 / APPENDIX III Pulse programs for simple MS and MS/MS experiments --- p.92 / APPENDIX IV Schematics of the proposed mechanisms for the formation of y8+ ions from the singly protonated arginine- and lysine-containing peptides --- p.99
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Simulation studies of the ion cooling processes of MALDI derived ions in fourier-transform mass spectrometry.January 2006 (has links)
Ko Ka Lung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Abstracts in English and Chinese. / Title page --- p.i / Abstract (English) --- p.ii / Abstract (Chinese) --- p.iii / Acknowledgement --- p.iv / Declaration --- p.v / Table of Content --- p.vi / List of Figure --- p.viii / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Matrix-assisted Laser Desorption / Ionization (MALDI) --- p.2 / Chapter 1.1.1 --- Evolution of Matrix-assisted laser desorption / ionization (MALDI) --- p.2 / Chapter 1.1.1.1 --- Lasers --- p.3 / Chapter 1.1.1.2 --- Matrices --- p.3 / Chapter 1.1.1.3 --- Sample preparation --- p.4 / Chapter 1.1.1.4 --- Desorption --- p.6 / Chapter 1.1.1.5 --- Ionization --- p.7 / Chapter 1.2 --- Fourier Transform Ion Cyclotron Resonance Mass Spectrometry with MALDI (FTICR-MS) --- p.9 / Chapter 1.2.1 --- History of Fourier Transform Ion Cyclotron Resonance Mass Spectrometry --- p.9 / Chapter 1.2.2 --- Basics of FTICR-MS --- p.11 / Chapter 1.2.3 --- FTICR couple with external ionization source --- p.15 / Chapter 1.2.4 --- Coupling of MALDI to FTICR --- p.16 / Chapter 1.3 --- Problems encountered on the coupling of MALDI to FTICR-MS --- p.17 / Chapter 1.4 --- Outline of present work --- p.19 / Chapter 2 --- SIMULATION METHOD --- p.20 / Chapter 2.1 --- Overview of the ion optics simulation --- p.21 / Chapter 2.2 --- History of SIMION Program --- p.22 / Chapter 2.3 --- Basics and theory of SIMION version 6.0 --- p.24 / Chapter 2.4 --- Simulation method --- p.26 / Chapter 2.4.1 --- Creating potential array --- p.27 / Chapter 2.4.2 --- User program --- p.29 / Chapter 2.4.3 --- Ion definition parameter --- p.31 / Chapter 2.4.4 --- Trajectories quality panel --- p.33 / Chapter 2.4.5 --- Data recording --- p.36 / Chapter 3 --- OPTIMIZATION OF RF-ONLY HEXAPOLE UNDER PULSE GAS CONDITION --- p.37 / Chapter 3.1 --- Introduction --- p.38 / Chapter 3.2 --- Simulation conditions --- p.39 / Chapter 3.3 --- Results and discussion --- p.40 / Chapter 3.3.1 --- rf-frequency (w) --- p.41 / Chapter 3.3.2 --- rf voltage (Vo-p) --- p.44 / Chapter 3.3.3 --- Pulse gas pressure(po) --- p.47 / Chapter 3.3.4 --- Trapping potential (VT) --- p.49 / Chapter 3.3.5 --- Effect of space charge --- p.53 / Chapter 3.4 --- Conclusions --- p.60 / Chapter 4 --- OPTIMIZATION OF DIFFERENT HEXAPOLE-BASED INTERFACES FOR PRE-TRAPPING COOLING --- p.61 / Chapter 4.1 --- Introduction --- p.62 / Chapter 4.2 --- Simulation conditions --- p.63 / Chapter 4.3 --- Results and discussion --- p.66 / Chapter 4.3.1 --- Static medium pressure interface --- p.66 / Chapter 4.3.1.1 --- Effect of pressure --- p.66 / Chapter 4.3.1.2 --- Effect of space charge --- p.70 / Chapter 4.3.2 --- Differential pressure model (Skimmer-based) --- p.73 / Chapter 4.3.2.1 --- Effect of pressure --- p.73 / Chapter 4.3.2.2 --- Effect of space charge --- p.76 / Chapter 4.3.3 --- A comparison of the optimal operating conditions for the three proposed interfaces --- p.81 / Chapter 4.3.4 --- Comparison of the theoretical results amd the experimental results --- p.83 / Chapter 4.4 --- Conclusion --- p.84 / Chapter 5 --- CONCLUSIONS --- p.85 / Chapter 5.1 --- Conclusions --- p.86 / REFERENCES --- p.R1 / APPENDIX --- p.A1
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Generation and fragmentation of protein radical ions in a fourier-transform ion cyclotron resonance mass spectrometer. / CUHK electronic theses & dissertations collectionJanuary 2010 (has links)
During the course of the systematic study, it was also discovered that doubly-protonated diarginated peptides containing multiple glutamic acid residues (E) (n>4) could suppress the backbone fragmentation of [M+2H]+· . Together with the results obtained from conformational searches, it was hypothesized that the interactions between carboxylic oxygens of E side chains and backbone amide hydrogens could stabilize the radical intermediate and thereby inhibiting the usual N-Calpha cleavages and H · loss from [M+2H]+·. / In order to ascertain the impacts of the structural features of polypeptide and oligosaccharide ions on the dissociation of these biomolecules under typical collision induced dissociation (CID) and electron capture dissociation (ECD) conditions, the dissociation patterns of even-electron precursor ions generated by protonation ([M+nH]n+)/metalation ([Metal+M]n+), odd-electron hydrogen-deficient precursor ions (M+·) generated by SORI-CID of [Cu(Tpy)M]2+ and odd-electron hydrogen-surplus precursor ions ([M+2H]+·) generated by ECD of [M+2H] 2+ were examined. It was found that backbone cleavages, with the generation of b/y and c/z ions, were dominant in the dissociation of [M+H]+ and [M+2H]+· respectively. Whilst in the dissociation of M+·, side chain loss reactions were the major fragments generated. For post translational modification (PTM)-containing peptides, the labile PTM groups were found to cleave preferentially in the dissociation of M+· and [M+H]+, but were found to be retained in the intact peptides and peptide fragments in the dissociation of [M+2H]+·. It is hypothesized that the different dissociation pathways is attributed to the different nature of radicals. Further to these, it was found that in the dissociation of oligosaccharides, similar cleavage patterns (glycosidic and cross-ring cleavages) were obtained regardless of the nature of the precursor ions (i.e. whether odd- or even-electron) and the ion activation conditions. / Chan, Wai Yi. / Adviser: T.W. Dominic Chan. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 145-152). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Fourier transform ion cyclotron resonance studies of dendrimers and metal porphyrin-phthalocyanine sandwich complexes.January 1996 (has links)
by Lim Che Lau. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 79-84). / Title Page --- p.i / Table of Contents --- p.ii / List of Tables --- p.iv / List of Figures --- p.v / List of Schemes --- p.vii / Acknowledgments --- p.viii / Abstract --- p.ix / Chapter CHAPTER 1: --- INTRODUCTION / Chapter 1.1. --- Historical Background --- p.1 / Chapter 1.2. --- FTICR with External Ion Source --- p.2 / Chapter 1.3. --- High Mass Analysis in FTICR --- p.4 / Chapter 1.4. --- Outline of Present Work --- p.7 / Chapter CHAPTER 2: --- INSTRUMENTATION AND EXPERIMENTAL / Chapter 2.1. --- Instrumentation --- p.8 / Chapter 2.1.1 --- Ion Source --- p.10 / Chapter 2.1.1.1. --- Liquid Secondary Ion Mass Spectrometry --- p.11 / Chapter 2.1.1.2. --- Electrospray Ionization --- p.12 / Chapter 2.1.2. --- Electrostatic Ion Focusing System --- p.15 / Chapter 2.1.3. --- ICR Analyzer Cell and Magnet --- p.18 / Chapter 2.1.4. --- Data Acquisition and Handling System --- p.22 / Chapter 2.2. --- Experimental --- p.22 / Chapter 2.2.1. --- Liquid Secondary Ion Mass Spectrometry --- p.22 / Chapter 2.2.2. --- Electrospray Ionization --- p.23 / Chapter 2.2.3. --- Nozzle-Skimmer Dissociation --- p.24 / Chapter 2.2.4. --- Sustained Off-Resonance Irradiation Collision- Induced Dissociation --- p.24 / Chapter 2.2.5. --- Data Acquisition and Processing --- p.27 / Chapter 2.2.6. --- Mass Calibration --- p.27 / Chapter CHAPTER 3: --- STRUCTURAL CHARACTERIZATION OF TERPYRIDINE-BASED POLYETHER DENDRIMERS AND THEIR IRON(II) METALLOCOMPLEXES BY LIQUID SECONDARY ION MASS SPECTROMETRY AND ELECTROSPRAY IONIZATION MASS SPECTROMETRY / Chapter 3.1. --- Introduction --- p.28 / Chapter 3.2. --- Sample Preparation --- p.29 / Chapter 3.3. --- Results and Discussion --- p.30 / Chapter 3.3.1. --- Liquid Secondary Ion Mass Spectrometry Studies --- p.30 / Chapter 3.3.1.1. --- Dendrimers --- p.30 / Chapter 3.3.1.2. --- Metallodendrimers --- p.41 / Chapter 3.3.2. --- Electrospray Ionization Mass Spectrometry Studies --- p.47 / Chapter 3.4. --- Conclusions --- p.53 / Chapter CHAPTER 4: --- STUDIES OF LANTHANIDE(III) PORPHYRIN- PHTHALOCYANINE HETEROLEPTIC SANDWICH COMPLEXES USING ELECTROSPRAY IONIZATION / Chapter 4.1. --- Introduction --- p.54 / Chapter 4.2. --- Results and Discussion --- p.55 / Chapter 4.2.1. --- Molecular Weight Determination --- p.57 / Chapter 4.2.2. --- Structural Elucidation --- p.65 / Chapter 4.2.3. --- Charge-Transfer Processes --- p.72 / Chapter 4.3. --- Conclusions --- p.76 / Chapter CHAPTER 5: --- CONCLUSIONS --- p.77 / References --- p.79
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Study of fluorescent properties of zinc phthalocyanine and derivatives using fourier transform spectroscopy.January 2008 (has links)
Han, Fangyuan. / Thesis submitted in: November 2007. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 68-72). / Abstracts in English and Chinese. / Title Page --- p.I / Thesis Committee --- p.II / Acknowledgements --- p.III / Abstract --- p.IV / 摘要 --- p.V / Table of Contents --- p.1 / List of Figures --- p.4 / List of Tables --- p.6 / Chapter Chapter 1 --- Introduction --- p.7 / Chapter Chapter 2 --- Fourier Transform Spectroscopy --- p.10 / Chapter A. --- The Michelson Interferometer and the Interferogram --- p.10 / Chapter B. --- The Link between the Interferogram and the Spectrum: the Fourier Transform --- p.12 / Chapter C. --- "Resolution, Apodization and Spectral Folding" --- p.13 / Chapter D. --- Advantages and Disadvantages of FTIR Spectroscopy --- p.17 / Chapter E. --- Time-resolved FTIR Spectroscopy --- p.18 / Chapter (1) --- Time-resolved Rapid Scan Scheme --- p.18 / Chapter (2) --- Step-scan Scheme --- p.19 / Chapter F. --- Several Considerations in Step-scan Time-resolved Spectroscopy / Chapter Chapter 3 --- Molecular Fluorescence --- p.24 / Chapter A. --- Transitions Between Electronic States --- p.24 / Chapter B. --- Absorption and Vibrational Relaxation --- p.26 / Chapter C. --- Internal Conversion and Fluorescence --- p.26 / Chapter D. --- Intersystem Crossing and Phosphorescence --- p.27 / Chapter E. --- Fluorescence Lifetime and Quantum Yield --- p.29 / Chapter Chapter 4 --- Fourier Transform Spectroscopy of Zinc Phthalocyanine and Derivatives --- p.32 / Chapter A. --- Introduction --- p.32 / Chapter B. --- Apparatus --- p.35 / Chapter (1) --- VERTEX 70 FTIR Spectrometer --- p.35 / Chapter (2) --- Excitation Source --- p.38 / Chapter (3) --- Detectors and the Transient recorder --- p.38 / Chapter (4) --- Samples and Sample Cells --- p.39 / Chapter C. --- Experimental Setup --- p.40 / Chapter (1) --- Absorption Experiments --- p.40 / Chapter (2) --- Emission Experiments --- p.42 / Chapter D. --- Results and Discussion --- p.45 / Chapter (1) --- Absorption and Fluorescence Spectra --- p.45 / Chapter (2) --- Fluorescence Lifetimes and Quantum Yields --- p.51 / Chapter (3) --- Time-resolved Fluorescence Spectra --- p.54 / Chapter E. --- Some Experimental Details --- p.60 / Chapter (1) --- Choice of Windows for Regular Tests of the Instrument Performance --- p.60 / Chapter (2) --- Configurations of the Transient Recorder in OPUS --- p.61 / Chapter (3) --- Configurations of Detectors in OPUS --- p.61 / Chapter (4) --- The Standard Method of Extracting Time Slices --- p.62 / Chapter (5) --- Parameters that Easily Cause Problems --- p.63 / Chapter (6) --- Elimination of Background Noises --- p.64 / Chapter Chapter 5 --- Concluding Remarks --- p.66 / Reference --- p.68
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Study of chemically modified food proteins by vibrational spectroscopyWong, Hing-wan. January 2006 (has links)
Thesis (Ph. D.)--University of Hong Kong, 200 . / Title proper from title frame. Also available in printed format.
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Fourier transform ion cyclotron resonance mass spectrometry instrumentation design and development reduction of ion cloud de-phasing and time-of-flight discrimination /Kaiser, Nathan Kenneth, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, December 2007. / Includes bibliographical references.
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