Our research purpose is to build up new and efficient methods to quantitate amounts of air-borne asbestos. A basic idea behind the methods is the use of a FT-IR instrument to measure the asbestos absorbances. Karen McCune, an ex-coworker in our group, developed three procedures to eliminate background absorbances from the filters on which the asbestos is collected. These procedures included the spectral subtraction, the chemical digestion, and the ashing of cellulose ester filters.My research has ultilized and expanded on the ashing procedure. First, the detection limits and linearity of the aforementioned transmission method were determined. Using amosite asbestos, we developed a standard curve from 40 tg to 2 µg which agreed well with Beer's Law. We determined that the detection limit of this method resulted from minutely contaminated salt and not from instrumental limitations. Even using highly pure KBr, CsCl, or KC1, similar detection limits were obtained.Second, the use of diffuse reflection to measure the asbestos absorbances was investigated. The method, much simpler than the transmission technique, consists of pouring the recovered asbestos-salt mixture into a small cup and obtaining the diffuse reflectance spectrum using a special accessory. A standard curve of amosite ranging from 40 p.g to 1 .tg was produced. One important observation was that when KCl adsorbed water from the air while a background spectrum was collected, the water absorption band contributed negatively to the area under the Si-O stretching region. This contribution prohibits the detection of smaller amounts of amosite. A standard curve of chrysotile asbestos ranging from 40 µg to 5 µg was also produced.Another goal of our research is to investigate the quantitation and identification capabilities when asbestos is present as mixtures of amosite, chrysotile, or other closely related silicates such as, kaolin. In conjunction with the diffuse reflection method, a curve fitting program was used to analyze the amount of each component in a mixture. First mixtures of amosite and chrysotile were studied. Then mixtures of amosite, chrysotile, and kaolin, mixtures which resemble the real world's environment, were studied.Overall, the FT-IR spectroscopic methods are more efficient and applicable than the traditional fiber-counting methods. Our methods not only objectively quantitate the amount of asbestos but also identify the type. / Department of Chemistry

M.Sc. (Chemistry) / A brief discussion of gas-solid interactions is given. The choice of reflection-absorption infrared spectroscopy (RAIRS) and the Kelvin probe as surface analytical techniques resulted in a visit to the physical research laboratory of Prof. J, Pritchard at Queen Mary College (London) . At this laboratory the author took part in the development of a wavelength modulation spectrometer. A spectrometer in the RAIRS mode and a Kelvin probe were used to study the adsorption of CO on a Cu(110) single crystal ...

Call number: LD2668 .T4 1959 R46

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

In addition, two unknown vibronic bands have been observed in the 12150 cm-1 region and 12450 cm-1 region. From the observed linewidths, isotopic shift of the transition frequency and appearance of intricate spectral pattern, it is plausible that these bands may be due to C2 under the perturbation of a state inaccessible by dipole transition. Further analysis of these bands are underway. / The unprecedented sensitivity and resolution achieved by our spectrometer allows the measurement of the very weak Phillips band system (A 1piu - X1Sigmag +) of C2 in the plasma of methane and helium at a ratio of 1:170 generated under very mild ac hollow cathode discharge conditions. A total of eleven vibronic bands of the Phillips system have been observed in the region from 10300 cm-1 to 14250 cm-1 and analyzed based on the previous work. Combining the observed transition frequencies with those from Douay et al. [J. Mol. Spectrosc. 131, 250 (1988)], a set of spectroscopic constants for both the X1Sigma g+ and A1piu states have been obtained using least-squares fitting. Excellent agreement has been found between determined molecular constants and those found in the literature. The observation of the high upsilon levels in the 1piu state allows the determination of high order anharmonic constants oeze and oeae for the first time. / This thesis reports the construction of a custom-designed experimental setup for the high resolution near infrared spectroscopic studies of molecular ions and radicals generated in gaseous plasma. The home-built near infrared spectrometer system has a frequency resolution of 500 kHz and a frequency accuracy of ∼0.0010 cm-1 with a detection sensitivity of DeltaI/I of 10-6 using zero background concentration modulated phase sensitive detection scheme. An in-house program has been designed for data acquisition, frequency calibration and data processing and storage. / Yeung, Shun Hin. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 129-134). / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

In an attempt at studying tunneling motions in the solid para -H2, the infrared absorption spectrum of matrix-isolated ammonia molecules (NH3) has been studied using Fourier-transform infrared (FTIR) spectroscopy. The transitions of the ammonia molecule in the v2 fundamental band were observed to exhibit very different pattern compared to those observed in other matrix materials. A preliminary analysis of the observed spectrum was also discussed based on the effect of crystal annealing and nuclear spin conversion of NH3. Transitions have been assigned to ortho and para species of NH3 based on there behavior in the presence of O2. For a more definitive assignment, further experiments will be necessary. / In this thesis, high resolution infrared spectrum of tetrahexacontapole (64-pole)-induced rovibrational W transition of solid parahydrogen (para-H2) was studied in samples containing ∼0.05% of orthohydrogen (ortho-H2) using high resolution near infrared diode laser spectroscopy. The rovibrational W1(0) transition (v =1 ← 0,J = 6 ← 0) has been observed at ∼6441.73 cm-1 with resolved triplet structure. These components were interpreted as the splitting of the M levels in the v = 1, J = 6 state due to crystal field interaction. The corresponding crystal field parameters based on the model of localized exciton in the W1(0) transition were determined. The good agreement of the corresponding parameters between the W1(0) transition and the previous W0(0) transition confirms the localization of the J =6 roton in both v = 0 and 1 states for solid para-H2. In addition, the temperature dependence of the W1(0) transition was studied in the temperature range of 2.7-8.0 K. The observed frequency shift has been ascribed to the change of isotropic intermolecular interactions as a result of molar volume change at different temperature / Song, Yan. / "November 2009." / Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 87-93). / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Near-infrared (NIR) spectroscopy is a widely used technique in quantitative analytical applications. Near-infrared spectroscopy is commonly used in clinical, environmental and industrial applications because of its compatibility with aqueous samples and with relatively thick samples. However, NIR spectra typically contain weak and highly overlapped spectral features which require multivariate data analysis techniques (chemometrics) to yield meaningful and chemically relevant information. This dissertation consists of two main themes which include applications of NIR spectroscopy combined with chemometrics to (1) model temperatures in clinically relevant aqueous-based samples and (2) model temperature and moisture content in nylon-6,6 polymers. This research employed overtone and combination bands of C-H, O-H and N-H bonds situated in the 4000 - 5000 cm-1 region to develop partial least-squares (PLS) regression models to predict analyte properties such as temperature, concentration and moisture content. The research described in the first part of this dissertation includes the development of a spectral preprocessing strategy based on the standard variate transform (SNV) and discrete wavelet transform (DWT) to isolate the low-frequency baseline information which carries the spectral features due to temperature fluctuations in aqueous-based samples. This approach was used to develop calibration models to determine the temperature of aqueous-based samples directly from their NIR spectra. This is an important development due to the fact that extreme temperature sensitivity of the underlying water bands can lead to poor quantitative analyte prediction results. These temperature models were developed using pH 7.4 phosphate buffer solutions spanning the range of 20 to 40.5 °C. Following the temperature models, a temperature-correction strategy based on the systematic pattern of concentration residuals was successfully developed to improve quantitative analyte predictions in aqueous-based samples. These analyte prediction models included glucose solutions and glucose-lactate mixture solutions prepared in pH 7.4 phosphate buffer. The computed temperature models gave excellent long-term prediction results. The temperature correction strategy gave promising results with the glucose solutions as well as the glucose-lactate mixture solutions. The research presented in the second part of this dissertation includes the development of calibration models to determine the temperature and moisture content of a piece of nylon-6,6 polymer directly from its NIR spectrum combining SNV and DWT procedures followed by PLS regression. Both models gave good long-term prediction results and predicted well across different nylon-6,6 sheets. Computed moisture model provides a reliable and fast method to determine the moisture content of a nylon polymer when compared to existing techniques. Extended research towards polymer characterization including preliminary investigations of inhomogeneous nature of nylon polymers using infrared microscopy is documented in the latter part of this dissertation.

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Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisors: John F. Rabolt and D. Bruce Chase, Dept. of Materials Science & Engineering. Includes bibliographical references.

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