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In the world today there is a massive dependency on fossil fuels as they are currently used to provide around 80% of the world’s energy. This is hugely detrimental to the environment and is a major contributory factor in climate change. Biofuel is a renewable energy source that is already being used to lessen some of the fossil fuel dependency. 2nd generation biofuels, by using non-food parts of plants, circumvent the food vs fuel argument, and by using farming waste or surplus can also avoid changing land use problems. Additionally liquid biofuels can use existing infrastructure for storage and delivery, and also fit into current lifestyles. Cost-effective 2nd generation biofuel production is directly affected by the presence of the polymer lignin in plant biomass, as it has been shown to impede enzymatic sugar release (saccharification) that is used for biofuel production. The work undertaken in this project developed a high-throughput methodology for the assessment of straw lignin content and composition across a large population of elite varieties in the economically important cereal crop, barley. Saccharification yield was also measured across the same population along with a number of other agronomically important traits, such as thousand-grain weight, biomass, mechanical stem properties and height. The data provided by these measurements allowed correlations between traits to be identified and their strength gauged. Genome wide association studies (GWAS) were also carried out and identified influential regions of the genome for each trait. The results revealed varying levels of association between measured traits and lignin content and monomeric constituents. Importantly a negative connection was shown between lignin content and saccharification yield, with lignin content being responsible for approximately 1/5th of the variation seen. Interestingly there was no correlation between lignin content and mechanical stem properties, an important factor in the agronomically important trait, lodging. GWAS results revealed a number of genomic regions that were influential across several traits indicating regions that would be difficult to separate through breeding due to their close proximities. However, unique QTL were identified for saccharification yield and lignin content providing candidates for breeding or genetic manipulation to improve the crop for biofuel production.

To help address the growing need for more and better sensors, an attempt was made to produce an in-situ mass and spectroscopic analysis of liquid and solid samples, to characterize samples and sensors. Spectroscopic analysis consisted of Raman and FTIR where mass measurements were carried out. The sample or sensor’s holder would allow for spectroscopic analysis as well as expose the sample to high temperatures and various chemicals. While Raman and FTIR were successful in producing reliable and consistent data, the constructed watt balance was not. This failure was a result of eliminate vibrational noise.

High temperature composite materials used in aerospace applications are exposed to extremely harsh conditions and must be able to withstand moisture and extremes of temperature. For example, the surface of an aircraft flying at Mach 2.4 has been estimated to reach around 177°C as a result of aerodynamic heating. This thesis has examined the effect of isothermal aging on two high temperature composite materials, a novel CSIRO composite and a commercial composite, both based on bismaleimides. Changes in mechanical properties and resin chemistry at two different temperatures were measured in order to assess the validity of accelerated aging tests. ¶ Delamination is a major cause of failure in materials, therefore, the Mode I interlaminar fracture toughness (GIC) of both materials was measured using the double cantilever beam (DCB) test. After aging at 250°C, the CSIRO CBR 320/328 composites exhibited better retention of GIC than the CIBA GEIGY Matrimid® 5292 composites. After 6 weeks of aging at this temperature, the CBR 320/328 material retained 100% of its initial interlaminar fracture toughness, however the Matrimid® 5292 material retained only 64% of its initial GIC. This trend was reversed at the lower aging temperature, when after 30 weeks of aging at 204°C, GIC was measured at 13% of its original value for the CSIRO composites, whereas it was measured at 64% in the case of the Matrimid® composites. When the fracture surfaces of these specimens were examined using scanning electron microscopy (SEM), the commercial material was observed to show an increasing degree of porosity with aging at 204°C. It was concluded that the good property retention at the temperature, despite this observed porosity, was a result of the excellent fibre/matrix adhesion exhibited by this material. ¶ Chemical degradation of the matrix of the composites was monitored by Fourier Transform Infrared (FTIR) and Raman Spectroscopy. Chemical changes at the core of both of these materials were found to occur concurrently with the observed changes in interlaminar fracture toughness. FTIR analysis of both matrix materials revealed the predominant degradation mechanism to be oxidation, specifically the oxidation of the methylene group bridging two aromatic rings common to the structure of both resins, was substantiated by the ingrowth of a broad peak centred at 1600cm-1. In addition to this, the pyromellitic anhydride unit present only in the CBR 320/328 composites was found to be highly resistant to the effects of aging, whereas the saturated imide, common to the cured structures of both materials, was observed to degrade. ¶ Raman spectroscopy showed an increase in the intensity of a peak at 1646 cm-1 in the Matrimid® 5292 composites aged at 250°C towards the centre of the sample as a result of increased reaction of the allylic carbon-carbon double bond. At 204°C, the degree of reaction increased towards the surface of the material, possibly as a result of a reverse Diels-Alder reaction. The glass transition temperatures of both materials were found to decrease with aging, with the exception of the CSR 320/328 composites aged at 204°C, which initially increased due to continued crosslinking of the resin. ¶ It is concluded that the degradation mechanisms at the two aging temperatures are very different. The reliability of results from accelerated (elevated temperature) aging tests has been drawn into doubt.

This thesis research focuses on the characterization of thinfilms made of poly(vinylidene fluoride) (PVDF) using an atomic force microscope. Thinfilms of PVDF were fabricated by a spin coating method with different conditions and characterized using the Atomic Force Microscopy (AFM) for morphological changes. Phase and conformational changes of PVDF were investigated using both wide angle X-ray diffraction (WAXD) and Fourier Transform Infrared Spectroscopy (FTIR). From this analysis, in-situ corona poling with annealing of spin-cast PVDF enabled a phase change from α to the mixture of β and γ phases. This process can decrease the complexity of the conventional method which requires mechanical stretching before poling PVDF in addition to thermal annealing for β phase transformation. This thesis describes some materials and surface properties of solution-cast PVDF thinfilms with various conditions such as topography and phase image, adhesion force, friction force, and roughness. Through the AFM topography and phase images, polymeric behavior and spherulites are discussed in the later part of the thesis.

Surface water reservoirs in rural areas of the Canadian prairies often have poor water quality due to contamination by dissolved organic carbon (DOC). DOC can activate growth of microorganisms in water distribution systems and form disinfection by-products (DBPs) in water treatment. The presence of microbiological contaminants and DBPs are potentially harmful to human health. Therefore, rapid and simple methods for DOC characterization are needed to evaluate potential water sources and to assist in understanding how best to remove DOC. The first objective of this project was to develop a sample preparation and analysis procedure utilizing Fourier Transform Infrared Spectroscopy (FTIR) to characterize the DOC content of water samples. The second objective was to compare FTIR analysis results for fractionated and un-fractionated water samples to more convention DOC characterization methods (such as UV, SUVA and specific THMFP). The third objective was to demonstrate the application of the procedure to source water assessment and water treatment process evaluation by characterizing the DOC content of several typical treated and un-treated prairie water samples at several locations in Saskatchewan.<p> In the first phase of the study prepared samples of known DOC concentration were separated into six fractions (hydrophobic acid (HPOA), hydrophobic neutral (HPON) and hydrophobic base (HPOB); and hydrophilic acid (HPIA), hydrophilic neutral (HPIN) and hydrophilic base (HPIB)) using resin fractionation techniques. FTIR and conventional UV spectroscopic measurements, DOC concentration, and trihalomethane formation potential (THMFP) measurements were taken on the un-fractionated samples and their fractions. A water matrix interference problem in the FTIR measurements was overcome by depositing a residue of dry solids from the aqueous solution containing the DOC on a flat, organic compound free and non-infrared absorptive gold plated slide before analysis. This simple evaporation procedure developed for concentrating water samples successfully deposited a solid residue for FTIR scanning. Scanning of the solid residue of each sample at multiple locations successfully produced a spectrum of average results suitable for interpretation.<p> Each organic fraction separated from the prepared samples of known DOC was then assessed using FTIR analysis. Comparison of the spectra from the resin adsorption fractions gave an indication of the relationship between functional groups and the hydrophobic/hydrophilic nature of the DOC. The results suggest that the hydrophobic fractions contain more aromatic functional groups. This demonstrates that the FTIR spectra can provide information regarding the hydrophobic/hydrophilic nature of the DOC as an alternative to the resin separation procedure. The sample preparation and FTIR analysis procedure was then used to characterize the DOC content of source and treated waters at several locations within Saskatchewan. The results of these initial investigations indicate the method can effectively identify the major organic functional groups present in source waters and the changes in the major functional groups that occur as the water is subjected to water treatment unit operations and processes. Further, the presence of several key functional groups is related to an increase in THMFP.

Interactions of progesterone with zwitterionic dipalmitoyl phosphotidylcholine (DPPC) multilamellar liposomes (MLVs) were investigated as a function of temperature and progesterone concentration by using three non-invasive techniques of Fourier transform infrared (FTIR) spectroscopy, turbidity at 440 nm and differential scanning calorimetry (DSC). The results show that 1mol% of progesterone does not induce a significant change in the shape of thermotropic profile of DPPC. However as progesterone concentration increases, the main transition temperature decreases and phase transition curve broadens. Higher concentrations (12, 18 and 24mol%) also decreased the transition temperature but not as significantly as lower concentrations. The characteristic pretransition of DPPC was completely disappeared upon the addition of progesterone. Progesterone disorders the phospholipid membranes in a concentration dependent manner. Furthermore, low concentrations of progesterone (3, 6 and 9mol%) increase the fluidity of the system but high concentrations (12, 18 and 24mol%) stabilize the membranes by decreasing the mobility of the acyl chains. The opposite effect of progesterone on membrane dynamics of low and high concentrations was also supported by turbidity studies at 440 nm. DSC peaks broaden and shift to lower temperature degrees with increasing concentrations up to 9mol% of progesterone. At 6 and 12mol% of progesterone, the curve contains more than one peak. This indicates the existence of phase separation. The pretransition of liposomes was eliminated for all samples containing progesterone. Analysis of C=O stretching bond in FTIR spectroscopy showed that progesterone does not make any hydrogen bonds with the interfacial region of DPPC liposomes, instead it induces free carbonyl groups in the system. Ester groups were found to be disordered by the addition of progesterone and the effect is profound with 6 and 9mol% concentrations. The head group of liposomes were found to make hydrogen bonding in the vicinity of 3mol% of progesterone in both phases and of 6mol% of progesterone in liquid crystalline phase by infrared spectroscopy of PO- 2 stretching mode. This hydrogen bonding is made either with the hydroxyl group of progesterone or with the water molecules around the head group. With other concentrations of progesterone, there is no evidence of hydrogen bond formation.

A sampling-window based approach was developed to collect and analyze the gases evolved during fire performance testing using the cone calorimeter. For this purpose, a Fourier Transform Intra-red (FTIR) Spectroscopy system and a Novatec analyzer were coupled to the cone calorimeter. An experimental gas sampling apparatus was designed and constructed and a sampling-window based method was developed. The sampling-window based method was initially tested using blue Styrofoam samples, then a small number of intumescent materials were also examined. Using the new integrated system, spectral scans were taken with an FTIR using 30s, 45s and 60s sampling windows, during off-gasing, fire growth, steady heat release rate, and fire decay stages of cone calorimeter testing. By focusing the sampling window on a specific stage of fire development the tests indicated that high concentrations of toxic gases were evolved during sample off-gasing, before ignition. In contrast to other methods that are designed to obtain total toxic gas yield over the full course of a cone calorimeter fire performance test, the sampling-window method here allows for a greater understanding of fire gas evolution at the various stages of fire growth and development. With the cone calorimeter coupled with a preconfigured “out of the box” lightweight portable ambient air analyzer and the sampling-window based approach developed, the fire gases associated with the polystyrene (blue Styrofoam) could be identified along with a number of the fire gases typically associated with the intumescent foam. For further analysis of fire gases produced, a calibrated, lab quality FTIR, with a higher resolution than the preconfigured “out of the box” lightweight portable ambient air analyzer may be required. However the system configuration and methodology would remain the same as developed here. The sampling-window based approach developed is useful for use in the development of other gas sampling techniques and can be used with other complimentary techniques such as Gas Chromatography (GC) and Mass Spectroscopy (MS). In such a combined Cone Calorimeter-GC-MS system, the GC is used to separate the various fire gases while the MS is used to identify all the components at a molecular level, and provide a more concise analysis of evolved fire gases. It is therefore recommended that the GC-MS technique also be developed for the cone calorimeter and used to compliment the FTIR technique developed in this study.

This thesis examines some of the challenges involved with using FTIR spectroscopy for cancer detection including sample preparation and correcting for distortion from cell scattering. Sample preparation affects the spectra differently depending on the cell type, and can lead to significant changes in cancer biomarkers for a given cell type. Biomarkers derived from specific cancer types under one sample preparation are not reliable for other cancer types, and may not be suitable for the same cancer type using a different sample preparation. Cell scattering can also significantly affect the cell spectra, and as a result, correcting for the cell scattering distortion leads to changes in the biomarkers. For reliable cancer detection controlling variability is critical, especially in the complex spectra of biological samples. Standard sample preparation methods and scattering correction post-processing could improve comparison of cancer detection methods.

Surface water reservoirs in rural areas of the Canadian prairies often have poor water quality due to contamination by dissolved organic carbon (DOC). DOC can activate growth of microorganisms in water distribution systems and form disinfection by-products (DBPs) in water treatment. The presence of microbiological contaminants and DBPs are potentially harmful to human health. Therefore, rapid and simple methods for DOC characterization are needed to evaluate potential water sources and to assist in understanding how best to remove DOC. The first objective of this project was to develop a sample preparation and analysis procedure utilizing Fourier Transform Infrared Spectroscopy (FTIR) to characterize the DOC content of water samples. The second objective was to compare FTIR analysis results for fractionated and un-fractionated water samples to more convention DOC characterization methods (such as UV, SUVA and specific THMFP). The third objective was to demonstrate the application of the procedure to source water assessment and water treatment process evaluation by characterizing the DOC content of several typical treated and un-treated prairie water samples at several locations in Saskatchewan.<p> In the first phase of the study prepared samples of known DOC concentration were separated into six fractions (hydrophobic acid (HPOA), hydrophobic neutral (HPON) and hydrophobic base (HPOB); and hydrophilic acid (HPIA), hydrophilic neutral (HPIN) and hydrophilic base (HPIB)) using resin fractionation techniques. FTIR and conventional UV spectroscopic measurements, DOC concentration, and trihalomethane formation potential (THMFP) measurements were taken on the un-fractionated samples and their fractions. A water matrix interference problem in the FTIR measurements was overcome by depositing a residue of dry solids from the aqueous solution containing the DOC on a flat, organic compound free and non-infrared absorptive gold plated slide before analysis. This simple evaporation procedure developed for concentrating water samples successfully deposited a solid residue for FTIR scanning. Scanning of the solid residue of each sample at multiple locations successfully produced a spectrum of average results suitable for interpretation.<p> Each organic fraction separated from the prepared samples of known DOC was then assessed using FTIR analysis. Comparison of the spectra from the resin adsorption fractions gave an indication of the relationship between functional groups and the hydrophobic/hydrophilic nature of the DOC. The results suggest that the hydrophobic fractions contain more aromatic functional groups. This demonstrates that the FTIR spectra can provide information regarding the hydrophobic/hydrophilic nature of the DOC as an alternative to the resin separation procedure. The sample preparation and FTIR analysis procedure was then used to characterize the DOC content of source and treated waters at several locations within Saskatchewan. The results of these initial investigations indicate the method can effectively identify the major organic functional groups present in source waters and the changes in the major functional groups that occur as the water is subjected to water treatment unit operations and processes. Further, the presence of several key functional groups is related to an increase in THMFP.