Lignin, a byproduct of the chemical pulping can be gasified to produce fuel gas and value-added products. Two lignins, MeadWestvaco (MWV) lignin and Sigma Aldrich (SA) lignin, were studied using two different reactors. A laminar entrained flow reactor (LEFR) was used initially to determine the effect of lignin type, temperature and residence time on char yield and fixed carbon conversion during pyrolysis and gasification. During both pyrolysis and gasification, the maximum decrease in char yield took place in the initial stage of the reaction and there was little change at longer residence times. There was not much difference between pyrolysis and gasification in the residence times obtained in the LEFR. Furthermore, a thermogravimetric analyzer (TGA) was used to study the effect of lignin type on pyrolysis and gasification. The reaction rates and char yields were affected by the lignin composition. Lignin pyrolysis showed similar behavior until 600°C but only the high-ash SA lignin showed secondary pyrolysis reactions above 600°C. Carbon gasification reactions were delayed in SA lignin. Na2CO3 addition made the primary pyrolysis reaction occur at a lower rate and enhanced the rate for secondary pyrolysis reactions. Fourier Transform Infrared (FTIR) Spectroscopy results showed that the significant loss of spectral detail started at different temperatures for MWV lignin and SA lignin. Kinetic parameters obtained using differential and Coats - Redfern integral method were comparable at lower temperatures but varied at high temperatures. Na2CO3 addition decreased the activation energy of primary pyrolysis.

Diffusion of linear and cyclic poly(oxyethylene) (POE) oligomers in poly(methyl methacrylate) (PMMA) matrix was investigated in situ using attenuated total reflectance (ATR) infrared (IR) spectroscopy technique. The temperatures of studies were 60 oC, 85 oC and 110 oC. A film of PMMA was solution-cast onto an ATR zinc selenide crystal and POE was added to the surface. The IR peak at 1109 cm-1 characteristic to ether bond present in POE was used for quantitative analysis. Deconvolution of this peak from IR spectra allowed us to determine the absorbance of diffusing component as a function of interdiffusion time. The data were fit using appropriate mathematical models from where the interdiffusion constants were extracted and used in diffusion interpretation. By looking at different molecular weight of cyclic and linear POE oligomers diffusing into high molecular weight PMMA matrix, it was possible to analyze how penetrant topology and its molecular weight are influencing the diffusion process. The results indicated that cyclic POE moves faster than linear analogous one and an increase in penetrant molecular weight slows down the interdiffusion. The knowledge gained from this study gives us a deeper understanding of transport behavior of low-molecular-weight additives, such as oligomers into polymer matrices and, in particular the influence of topology on diffusion.

The Bryan/College Station (B/CS) region has been reported to have elevated concentrations of dissolved organic carbon (DOC) in surface water. Increased DOC concentrations are worrisome as DOC has been shown to be an energy source for the recovery and regrowth of E. coli and many watersheds are impaired by high bacteria levels. To examine the sources and fates of DOC in rural and urban regions to better understand DOC movement though the environment, seven watersheds were studied. To investigate source, streams were analyzed using diffuse reflectance near infrared spectroscopy (DR-NIR) and carbon isotopes. Fate of DOC was determined through monthly streams samples, gathered between March 2011 and February 2012, which were incubated for biodegradable DOC (BDOC). Soil in the region was sampled based on land use categories. Soil was analyzed for DOC and BDOC as well as DOC adsorption, the other major fate of DOC. Above ground vegetation was sampled in conjunction with soil and analyzed for BDOC. Data indicated that fecal matter from cliff swallows provided considerable organic material to streams in the B/CS region as shown through DR-NIR. Carbon isotope values in streams ranged from -23.5 +/- 0.7% to -26.8 +/- 0.5%. Stream spectra may be able to predict carbon isotope values in streams (Adj. R2 = 0.88). Mean annual stream DOC concentrations ranged from 11 +/- 3 mg/L to 31 +/- 12 mg/L, which represents a significant decrease in DOC between 2007 and 2011. Concurrent increases in pH and conductivity were also recorded. The decrease in DOC and the increases in pH and conductivity may be due to impacts of high sodium irrigation tap water. Biodegradable DOC was low in streams, which is likely due to DOC being present in streams in refractory forms that are resistant to microbial breakdown. Soil chemistry, including soil adsorption, was greatly influenced by sodium. The elevated adsorption coefficients and release values seen in highly developed and urban open areas can be attributed to frequent exposure to high sodium irrigation water. The results indicate that sodium is a major driver of DOC in the system. Sound management decisions concerning irrigation water chemistry and urban development might eventually emerge to protect water quality as a result of this research.

Vibrational spectroscopy, mainly infrared spectroscopy, has been applied to bacteria, yeast and archaea cells for many years, for example, for the purpose of developing a rapid method of identification. More recently microcolonies have been used for consistency with the preparation and culture protocols of traditional microbiological methods. Heterogeneity of microcolonies has not been well studied. Investigation of heterogeneity may provide detailed biochemical information leading to an understanding of how colonies grow and the link to the growth cycle. Investigation of regions within bacterial colonies using FT-IR microspectroscopy was applied to two prokaryotes, the Gram-negative archaeon Halobacterium salinarium and the Gram-positive bacterium Bacillus stearothermophilus. Two-dimensional maps of the entire colony and point maps, spectra taken from key regions such as the periphery and centre of the colony, were acquired. The approximate size of the colonies ranged from 250-950 μm. The infrared data for the Gram-negative archaeon, H. salinarium supports that for the Gram-positive bacterium, B. stearothermophilus, despite the microorganisms being of different domains and Gram types. It was concluded that the periphery of the microcolony approximately equates to the exponential growth phase (and possibly the lag phase) where the younger cells reside, while the centre approximates to the death and stationary phases. However the spatial resolution proved to be a limiting factor, so Raman microspectroscopy was employed to address this. Raman spectra across the diameter of microcolonies ranging from 100-300 μm of the pigmented bacterial species Halobacterium salinarium revealed variations in the carotenoid bands. It was suggested that these variations correspond to growth rings, which relate to the growth cycle and the consolidation and migration phase of the cells. The carotenoid variation was rather clear mainly due to the enhanced spectral intensity due to resonance with the laser excitation source. Hence, pigmented bacterial colonies are ideal to study by Raman spectroscopy. The results of this particular aspect of the research are to be published in the Journal of Raman Spectroscopy [1]. In addition, a connection between the consolidation and migration phases and the phases of the growth cycle has been postulated as a novel hypothesis to link the periodic dynamics of the colony and the growth mechanisms at the cellular level. The Raman microspectroscopic study was extended to non-pigmented bacterial colonies directly on the growth medium. This was a more difficult endeavour as the spectra taken do not have the resonance enhanced advantage of a pigmented bacterium. In addition the sampling volume can consist of variable amounts of growth medium thus decreasing the signal-to-noise ratio and reducing the accuracy of subsequent spectral calculations. However, this was overcome to a large extent by the use of confocal microscopy. The non-pigmented bacterial colonies investigated were Bacillus stearothermophilus and Bacillus subtilis. Analysis, by band area ratios and by chemometric approaches, of radial line map spectra of both Bacillus species revealed variation of nucleic acid concentration. The higher nucleic acid concentration is likely to be a result of cells in the exponential growth phase as rapid growth of new cells is occurring.

Bibliography: leaves 151-166. / xi, 166 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis describes the development of two novel and complementary analytical approaches for assaying cyanoalanine non-protein amino acids. These assays are used to determine the distribution of these compounds both within and between plants and to identify accessions of common vetch which contain low levels of the cyanoalanine non-protein amino acids in germplasm collections. These analytical tools are used to correlate toxicity observed in animal feeding experiments with the cyanoalanine content. This thesis covers also the first report of the use of diffuse reflectance using dispersive infrared spectrometry for the "in situ" quantification of specific organic components from plant tissue as well as the first use of micellar electrokinetic chromatography for the quantitative analysis of 9-fluorenylmethyl chloroformate (FMOC) derivatised and non-derivatised components of extracts from plant material. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 1997

Geopolymer chemistry governs the formation of an X-ray amorphous aluminosilicate cement material. Binders form at ambient temperatures from a variety of different raw material sources, including industrial wastes. Early research in this field was based around investigating binder material properties; however, more recently, geopolymer formation chemistry has been intensively studied. Better understanding of the chemical processes governing geopolymer curing reactions will allow a wider variety of waste materials to be utilised and also the tailoring of binder properties for specific applications. (For complete abstract open document).

Cleaning validation of pharmaceutical manufacturing equipment is required by legislation. Generally, wet chemical techniques are employed using swabbing and/or rinse sampling methods. These are generally either selective and time consuming, or less selective and give results in a shorter period. The infrared reflection absorption spectroscopy (IRRAS) technique explored here attempts to deliver accurate, selective surface contamination information in real time to complement current methods and reduce down-time. The IRRAS instrument used in this research is a Fourier transform infrared (FTIR) spectrometer coupled by an IR fibre-optic cable to a grazing-angle sampling head with a fixed incidence angle of 80°. The introduced flexibility permits collection of in situ spectra from contaminated surfaces. Calibration models are developed using the multivariate, linear partial least squares (PLS) statistical method. The research focuses on sodium dodecyl sulfate (SDS), a model cleaning agent, on metal (aluminium and stainless steel) and dielectric (glass, EPDM and silicone) surfaces. The effects of surface finish are investigated for SDS on stainless steel. Calibrations for SDS and paracetamol in the presence of each other on glass surfaces are examined, as well as a common industrial cleaner (P3 cosa® PUR80) on polished stainless steel. For the calibration sets in this thesis, RMSECV values were < 0.41 µg cm⁻², corresponding to conservative surface residues detection limits of better than ~0.86 µg cm⁻². However, RMSECV values depend on the calibration loading range, and the detection limits were typically ~0.2 µg cm⁻² for loading ranges 0-2.5 µg cm⁻². These are below visual detection limits, generally taken to be 1-4 µg cm⁻², depending on the analyte and substrate. This shows that IRRAS is a viable method for the real-time detection and quantification of surface contamination by surfactants and active pharmaceutical ingredients on metals and dielectrics.

Doctor of Philosophy / In this thesis, three experiments were conducted to monitor: (i) muscle oxygenation and electromyographic activity of the biceps brachii after exercise-induced muscle damage (ii) muscle oxygenation after downhill walking-induced muscle damage, and, (iii) muscle oxygenation following a bout of vigorous concentric exercise. Maximal eccentric exercise (EE) of biceps brachii resulted in significantly increased mean resting oxygen saturation and decreased deoxyhaemoglobin. During isometric contractions at 50% and 80% of subjects’ maximum voluntary torque (MVT), oxygen desaturation and resaturation kinetics and volume were significantly decreased after EE, and these declines were significantly prevalent over the following 6 days. Additionally, a significant shift in median frequency intercept (measured by electromyography; EMG) towards lower frequencies was observed during isometric contractions at both 50% and 80% MVT after EE in the exercised arm. After an exhaustive session of downhill walking, another form of EE, resting total haemoglobin and oxyhaemoglobin decreased. Furthermore, during isometric contractions at 30%, 50% and 80% of MVT, prolonged and significant increases were observed in oxygen desaturation and resaturation kinetics and volumes after ambulatory EE. In contrast to the two EE experiments, concentric contractions did not evoke any prolonged changes in muscle oxygenation. Collectively, the findings of this thesis revealed significant and prolonged changes in muscle oxygenation at rest and during exercise, following sessions of strenuous eccentric exercise. Although not clear, the possible mechanism responsible for the changes in muscle oxygenation after EE could be increased resting muscle oxygen utilization due to probable muscle damage and a subsequent requirement of energy demanding repair processes. Concentric exercise resulted in fatigue, but it did not affect muscle oxygenation. Although a prolonged reduction in EMG median frequency intercept was observed after EE, this was not closely time-associated with the biochemical, anthropometric or functional markers of muscle damage.

Thesis (M.S.)--State University of New York at Binghamton, Department of Physics, 2006. / Includes bibliographical references.

Thesis (Ph.D.)--McMaster University (Canada), 1989. / Source: Dissertation Abstracts International, Volume: 62-13, Section: A, page: 0000.