Three new quantitative Fourier transform infrared (FTIR) spectroscopic methods were developed to measure key lubricant condition monitoring parameters; total acid number (TAN), total base number (TBN), and moisture (H2O). All methods employ a common sample-handling accessory and are based on the addition of specific reagents designed to react stoichiometrically with target species in oils, with quantification being carried out using differential FTIR spectroscopy. The combined use of a stoichiometric reaction and differential spectroscopy overcomes the need for a reference oil, which has traditionally hindered quantitative analysis of lubricants by FTIR spectroscopy. Potassium hydroxide, trifluoroacetic acid (TFA) and 2,2-dimethoxypropane (DMP) were the stoichiometric reagents used to develop the FTIR TAN, TBN and H2 O methods, respectively. Calibrations were developed using either peak height measurements or partial least squares (PLS) regression and the methods were validated using standard addition techniques, as the ASTM (American Society of Testing and Materials) standard methods were not sufficiently reproducible to make valid comparisons. Validation of the methods indicated that the TAN, TBN and H2O methods had accuracies of +/-0.095 mg KOH/g, +/-0.5 mg KOH/g and +/-32ppm respectively and corresponding reproducibilities of +/-0.05 mg KOH/g, +/-0.17 mg KOH/g and +/-22 ppm. The TAN, TBN and H2O methods were implemented on a Continuous Oil Analysis and Treatment (COATRTM) System, integrating instrumentation, software and sample handling so as to provide packaged, user and environmentally friendly analytical methods that are alternatives to conventional ASTM wet chemical methods.

Thesis (Ph. D.)--University of Hong Kong, 2008. / Also available in print.

Thesis (Ph.D.)--Texas Christian University, 2008. / Title from dissertation title page (viewed May 7, 2008). Includes abstract. Includes bibliographical references.

Thesis (Ph.D.) -- University of Rhode Island, 2007 / Typescript. Includes bibliographical references (leaves 178-184).

Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2005. Directed by Boris Mizaikoff. / Hunt, William, Committee Member ; Weck, Marcus, Committee Member ; Mizaikoff, Boris, Committee Chair ; Janata, Jiri, Committee Member ; Orlando, Thomas, Committee Member. Includes bibliographical references.

Thesis (Ph. D.)--University of Canterbury, 2007. / Typescript (photocopy). "January 2007." Includes bibliographical references. Also available via the World Wide Web.

The aim of this work was to assess the potential of FTIR spectroscopy in the analysis of the cis and trans fatty acid contents of fats and oils. Preliminary studies on the liquid and solution phase spectra of individual FAME'S (fatty acid methyl esters), and on mixtures of FAME'S, were conducted to establish whether spectral features enhanced by FTIR could be used to provide improved methods of determining cis and trans contents. A number of previously unreported bands and spectral features associated with the cis and trans isolated double bond(s) were discovered. None of the trans bands were considered suitable for quantitation, however, methods of determining the cis content were developed, based on the the two bands listed below. These methods were compared with current IR methods, and with a capillary GC method. (a) The CIS C=C stretching band (1654 cm-1). (b) An unassigned band at 913 cm-1, observed only in the spectra of non-conjugated di- and tri-unsaturated FAME'S. All the established methods as well as those developed in this work, for the quantitative analysis of FAME'S have inherent disadvantages. For example, with the capillary GC method, difficulties are encountered in resolving and identifying samples containing complex mixtures of isomers. With the IR techniques, the difficulties involve the elimination of interfering bands, and the absorbance of similar fatty acids at the same frequencies. The application of GC-FTIR was seen as a logical extension of this project, because it offered a great potential for the separation and charactisation of components of complex mixtures. Studies conducted on vapour phase spectra showed that the identification of many FAME'S could be ascertained from various band ratios. Furthermore, band ratios could be used to quantify the cis/trans content of co-eluting isomers. Different types of capillary columns were tried, and optimum conditions established where possible.

This study focuses on the characterization of InAs and InAs1-xSbx epitaxial layers by infrared reflectance and transmittance spectroscopy and Hall measurements. Reflectance measurements were performed in order to obtain the dielectric parameters and to extract from these information about the electrical properties (mobility and carrier concentration) of this important III-V material system. The transmittance measurements were used to determine the bandgap of InAsSb. Infrared reflectivity and transmittance measurements were performed in the wavelength range 200 – 2000 cm-1 on InAs and InAsSb layers grown on three types of substrates. A classical two oscillator model that takes into account both the free carriers and the lattice, was used to analyse the reflectance data using the BMDP® computer curve fitting software. The dielectric parameters and the electrical properties (carrier concentration and mobility) were extracted from the simulations. Due to the low free carrier concentration in the epitaxial structures, the plasma resonance frequency (ωp) values obtained from the simulations of reflectance spectra measured above 200 cm-1, were in the order of 20-30 cm-1. These low values were confirmed by direct measurements of ωp in reflectance spectra obtained in the range 15-200 cm-1. The simulated carrier concentration and mobility values determined optically were compared to the values determined by Hall measurements at room temperature and previously reported values by other researchers. The simulated values obtained were in reasonable agreement with the Hall values. The simulated and measured carrier concentrations obtained for InAs layers were significantly higher than the intrinsic carrier concentration for InAs at room temperature, indicating notable concentrations of donors resulting from the growth process.

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No description available.