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Barley grain is one of the main sources of feed for ruminants in Canada. Although barley varieties may have similar chemical composition, they exhibit different rumen degradation characteristics and nutrient availabilities. These biological differences may be related to structural chemical make-up or structural features among the varieties. The objectives of this study were to use the in situ technique and two Mid-IR Spectroscopy techniques, Diffuse Reflectance Fourier Transform IR Spectroscopy (DRIFT) and Synchrotron-based Fourier Transform IR Microspectroscopy (SFTIRM) to determine ruminal nutrient availabilities and inherent structural features in the hull, seed and endosperm of six barley varieties (AC Metcalfe, McLeod, CDC Dolly, CDC Helgason, CDC Trey, and CDC Cowboy) and to study the relationships between structural characteristics, mean and median particle size and nutrient availability. The nylon bag technique was used to incubate coarsely dry-rolled barley samples for 0, 2, 4, 8, 12, 24 and 48 h in the rumen of three mature Holstein dry dairy cows, which were ruminally cannulated. The rumen degradation kinetics of dry matter (DM), crude protein (CP) and starch were determined using first order degradation kinetics equations. Results indicated that there were significant differences in the mean and median particle size, degradation kinetics of each individual nutrient (DM, CP, and starch) among the six barley varieties. CDC Helgason showed the lowest degradation rate and extent of all nutrients (DM, CP, and starch) among the six barley varieties with larger particle size. Compared with other five varieties, CDC Helgason may be more suitable for ruminants feeding because of the lowest degradation rate and extent. The results also revealed a strong correlation between median particle size and the rate and extent of rumen degradation.<p> The results also showed that both DRIFT and SFTIR techniques associated with uni- and two multi- variate analyses were capable to efficiently discriminate and classify the inherent molecular structural features among the different varieties of barleys. Uni-variate analyses were conducted using both the DRIFT spectroscopy (hull and whole seed sample) and SFTIR microspectroscopy (endosperm tissue). The results from hull samples showed significant differences in the peak area of aromatic lignin, cellulosic compound, and total carbohydrates (CHO), and the ratio of lignin to cellulosic compound among the six barley varieties. The results from whole seed samples showed significant difference in the peak area and height of Amide I, peak area of total CHO and structural CHO (cellulosic), and the ratio of Amide I to total CHO area, and the ratio of total CHO to structural CHO. Significant differences were also found in the SFTIR results from endosperm tissue. With two multivariate spectral analysis techniques: Agglomerative hierarchical cluster (AHCA) and Principal component analyses (PCA) applied on whole seed sample, the CDC Helgason was distinguished from AC Metcalfe, CDC Dolly, McLeod and CDC Cowboy in fingerprint (1800-800 cm-1) and CHO region (1185-800 cm-1), from AC Metcalfe, McLeod and CDC Cowboy in protein region (1715-1485 cm-1). Information from this study involving probing the seed internal structure of barley may provide a further insight as to why barley varieties exhibit different rumen degradations.

Barley grain is one of the main sources of feed for ruminants in Canada. Although barley varieties may have similar chemical composition, they exhibit different rumen degradation characteristics and nutrient availabilities. These biological differences may be related to structural chemical make-up or structural features among the varieties. The objectives of this study were to use the in situ technique and two Mid-IR Spectroscopy techniques, Diffuse Reflectance Fourier Transform IR Spectroscopy (DRIFT) and Synchrotron-based Fourier Transform IR Microspectroscopy (SFTIRM) to determine ruminal nutrient availabilities and inherent structural features in the hull, seed and endosperm of six barley varieties (AC Metcalfe, McLeod, CDC Dolly, CDC Helgason, CDC Trey, and CDC Cowboy) and to study the relationships between structural characteristics, mean and median particle size and nutrient availability. The nylon bag technique was used to incubate coarsely dry-rolled barley samples for 0, 2, 4, 8, 12, 24 and 48 h in the rumen of three mature Holstein dry dairy cows, which were ruminally cannulated. The rumen degradation kinetics of dry matter (DM), crude protein (CP) and starch were determined using first order degradation kinetics equations. Results indicated that there were significant differences in the mean and median particle size, degradation kinetics of each individual nutrient (DM, CP, and starch) among the six barley varieties. CDC Helgason showed the lowest degradation rate and extent of all nutrients (DM, CP, and starch) among the six barley varieties with larger particle size. Compared with other five varieties, CDC Helgason may be more suitable for ruminants feeding because of the lowest degradation rate and extent. The results also revealed a strong correlation between median particle size and the rate and extent of rumen degradation.<p> The results also showed that both DRIFT and SFTIR techniques associated with uni- and two multi- variate analyses were capable to efficiently discriminate and classify the inherent molecular structural features among the different varieties of barleys. Uni-variate analyses were conducted using both the DRIFT spectroscopy (hull and whole seed sample) and SFTIR microspectroscopy (endosperm tissue). The results from hull samples showed significant differences in the peak area of aromatic lignin, cellulosic compound, and total carbohydrates (CHO), and the ratio of lignin to cellulosic compound among the six barley varieties. The results from whole seed samples showed significant difference in the peak area and height of Amide I, peak area of total CHO and structural CHO (cellulosic), and the ratio of Amide I to total CHO area, and the ratio of total CHO to structural CHO. Significant differences were also found in the SFTIR results from endosperm tissue. With two multivariate spectral analysis techniques: Agglomerative hierarchical cluster (AHCA) and Principal component analyses (PCA) applied on whole seed sample, the CDC Helgason was distinguished from AC Metcalfe, CDC Dolly, McLeod and CDC Cowboy in fingerprint (1800-800 cm-1) and CHO region (1185-800 cm-1), from AC Metcalfe, McLeod and CDC Cowboy in protein region (1715-1485 cm-1). Information from this study involving probing the seed internal structure of barley may provide a further insight as to why barley varieties exhibit different rumen degradations.

Current understanding of molecular-level interactions is inadequate to explain the initial moments of bacterial adhesion. Such information is required to develop appropriate models for bacteria-surface interactions and predictions of cell transport in subsurface environments. Bacterial adhesion is influenced by bacterial surfaces, substratum physical-chemical characteristics, and solution chemistry. Extracellular polymeric substances (EPS), surface proteins, and lipopolysaccharides (LPS) mediate cell adhesion and conditioning film formation via direct bonding to a substrate. The goal of this dissertation is to probe molecular-scale interactions of cell surface macromolecules at mineral surfaces under environmentally-relevant conditions. Four primary investigations are presented in this dissertation. The first study uses in situ attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy to reveal that prior to Mn-oxidation via Pseudomonas putida GB-1, cell adhesion to ZnSe is favorable. Subsequent Mn-oxidation results in increased extracellular proteins expression. Conversely, planktonic cell adhesion is inhibited for Mn-oxide coated cells via blocking of surface proteins. The second investigation reveals the formation of inner-sphere complexes between bacteria surface phosphoryl groups and nanohematite (α-Fe₂O₃). Spectra of bacteria (P. aeruginosa PAO1, Shewanella oneidensis MR-1, and Bacillus subtilis) on α- Fe₂O₃ contain peaks indicative of P-OFe inner-sphere bonding. Spectra collected for oxide-adsorbed model P-containing compounds give spectral signatures similar to those P-OFe bonding interactions observed for whole cell and EPS. The behavior of P. aeruginosa serotype 10 LPS in aqueous solutions was investigated in the third study. Ionic strength, pH, and electrolyte composition were varied during collection of ATR-FTIR and dynamic light scattering (DLS) data. Results reveal stable aggregate Na-LPS aggregates, whereas binding of Ca²⁺ to phosphate groups in the lipid A region leads to aggregate reorientation and increased interaction with ZnSe (hydrophobic). DLS data demonstrate decreasing hydrodynamic radius of LPS aggregates with increasing I and decreasing pH. In the fourth investigation, ATR-FTIR was used to probe the solid-solution interface of LPS on surfaces of ZnSe, Ge, α-Fe₂O₃, and α-Al₂O₃ in solutions of varying ionic composition and pH. Na-LPS aggregates remain stable and spectra are biased towards solution phase LPS. Ca-LPS aggregates are disrupted, leading to enhanced interaction with surfaces via hydrophobic (lipid A- ZnSe) and electrostatic (O-antigenhydrophilic surfaces) interactions.

In order to measure the thickness of a protein layer on a structured surface of silicon rubber, we have used ellipsometry and Fourier transform infrared (FTIR)-spectroscopy. The aim was to determine whether this type of measurement method can be used on protein layers or not. By hot-embossing a specific pattern of micrometre-sized pillars was created on the surface of the silicon rubber, which then was exposed to a phosphate buffer solution (PBS) containing human serum albumin (HSA) protein. FTIR measurements confirmed that proteins had attached to the surface. Ellipsometric studies were made and even though the protein layer was too thin to be measured, a simulation was made that revealed that a protein layer needs to be at least 1,5 nm to be measured properly with this method. We can also see that the protein molecules can get out of the solution, to find their way into the small pits of the samples.

About a hundred samples of y-manganese dioxide covering three materials coded SBP- A, Faradiser M and R2 have been reduced chemically by insertion of H through controlled additions of hydrazine hydrate solutions at about 1 °C. The H-inserted samples and the starting materials were subjected to chemical analysis for oxidation state, X-ray diffraction (XRD) for structure study and Fourier Transform Infrared (FTIR) spectroscopy to gain information on OH bonding. Additional techniques including FTIR spectroscopy at low temperature (~ -180 °C), electrode potential measurement and scanning electron microscopy (SEM) have also been applied. The intergrowth structure of the starting materials consisted of ramsdellite intercepted with pyrolusite layers, known as de Wolff faults, and quantified by the fraction of pyrolusite layers Pr. An additional structural parameter for these materials was the amount of micro twinning (Tw) across the 021/061 ramsdellite planes. This parameter, introduced by Pannetier, is given in percent. Values of (Pr , Tw) have been given as (0.41 , 17) for SBP-A, (0.70,10) for Faradiser M and (0.41, ~100) for R2. Upon H-insertion, the structure of the starting materials expanded homogeneously in a direction and to an extent which depended on the Pr and Tw parameters. Faradiser M, with high Pr and very low Tw, expanded homogeneously in the direction of the b lattice dimension up to an insertion level of 0.69 of s in MnOn/Hs. Above this level, the initial structure changed suddenly into the structure of the final product: the insertion then proceeded homogeneously in the new phase. The main changes were an expansion of the octahedra and a rotation leading to hinged tunnels. This is the first time that the existence of two solid solutions in the MnO2/H system has been noted. With SBP-A, the amount of microtwinning restricted the homogeneous expansion of SBP-A to s = 0.28, which occurred predominantly in the a direction. Further insertion broke the twinning boundary and formed a demicrotwinned phase of composition MnOn Ho.68 in which the tunnels were also hinged. Thereafter H-insertion proceeded heterogeneously from 0.28 to 0.68 in s. Above s = 0.68, the structure developed homogeneously towards that of the fully H-inserted product. The extensive microtwinning in R2 allowed for a homogeneous expansion, thought to be isotropic to maintain the microtwinned structure, up to s = 0.39. Higher insertion levels led to the expansion to proceed heterogeneously to a composition of MnOn Ho.63. Above s = 0.63, a new phase, the final product, was formed with fully demicrotwinned structure and fully hinged tunnels. R-insertion into y-manganese dioxide has never been reported to occur in three stages previously. The FTIR study at room temperature has shown absence of OH bond vibrations at insertion levels prior to the hinging of the tunnels, in contrast to their presence after the structure has rotated and the tunnels had hinged. This is seen as a strong indication of H mobility in the initial structure. The hinging is necessary for OH bonding as it brings the 02 and 01 oxygens closer allowing the proton to bond both covalently and by H-bonding. At low temperature, initially mobile hydrogen could be trapped and OR bonds formed only in H-inserted R2. This was linked to 061-microtwinning. The absence of OH bonds at low temperature in SBP-A and Faradiser M led to the conclusion that these materials have no 061 micro twinning faults. The absence of OH bonds at low temperature in the starting materials, particularly in R2, strongly questions the postulated OH groups in the structure of y-MnO2, according to the cation vacancy model. Electrode potential data supported the above conclusions in terms of the stages of the H-insertion. The battery activity of the materials seemed to be related to the extent at which the materials kept the initial structure with non-hinged tunnels. Comparison with previous works on the same materials suggested that the differences could be accounted for by the kinetics of the H-insertion. While protons in this work were released spontaneously on the surface of the MnO x , their diffusion into the bulk was slow due to the low temperature. In the compared literature, the reverse applies.

Historically, coatings were processed from natural oils, fats, and resins; the first well-known and widely used being lacquer [Meir-Westhues, 2007]. In the 20th century, synthetic resins were developed to achieve coatings with improved properties. Of these coating compositions, polyurethanes (PURs) were one of the most prevalent. Polyurethanes became possible in 1937 when Otto Bayer developed the diisocyanate polyaddition process [Randall et al, 2002]. Since that time, literally thousands of PUR compositions have been used commercially. The primary application of interest in this study is that of coatings for wood substrates. It is well-known among materials researchers that there can be a number of differences between microwave and conventional materials treatment techniques [Clark et al, 1996], including enhanced reaction rates, lowered processing temperatures for some products, and selective interactions in composite systems. The primary goals of this research were to determine (1) whether microwave energy affected the cure rate in a water-based, aliphatic PUR, and (2) if there was an effect of microwave frequency on the cure rate. The primary tool for determining extent of cure in the PUR samples was Fourier transform infrared spectroscopy (FTIR). Using this characterization method, the changes in intensities of four bonds specific to the PUR composition were followed. It was determined that, in the particular PUR composition studied, microwave energy had an effect on the cure rate when compared with conventional heating, and that there was a frequency effect on the cure rate. Additionally, a deeper understanding of the use of FTIR spectroscopy techniques for studying cure kinetics was developed. / Master of Science

Economic utilisation of biogas arising from sewage sludge is hampered by the need to remove siloxanes, which damage gas engines upon combustion. This thesis applies on-line Fourier transform infrared spectroscopy to measure siloxanes in biogas upstream and downstream of the activated carbon vessels designed to adsorb siloxanes. On-line analysis provides accurate measurement of siloxane concentrations with a detection limit below the siloxane limits set by engine manufacturers, high data intensity and timely identification of breakthrough. Cost savings of up to £0.007 kWh- 1 may be realised compared to existing grab sampling. Using on-line analysis, the performance of full-scale and bench-scale carbon vessels were measured. Full-scale carbon contactors are typically operated at Reynold’s numbers close to the boundary between the laminar and transitional regimes (Re = 40 - 55). This thesis demonstrates, at full- and bench-scale, that increasing the Reynold’s number to site the adsorption process in the transitional regime increases media capacity, by 36% in dry gas and by 400% at 80% humidity. It is postulated that the change in gas velocity profile which occurs as Reynold’s number increases reduces the resistance to siloxane transport caused by gas and water films around the carbon particles, and therefore increases the rate of the overall adsorption process. In the laminar regime (Re = 31) increasing humidity from zero to 80% led to the classical stepwise reduction in adsorption capacity observed by other researchers, caused by the increasing thickness of the water film, but in the transitional regime (Re = 73) increasing humidity had no effect as no significant water film develops. It is therefore recommended that siloxane adsorption vessels should be designed to operate at Reynold’s numbers above 55. By choosing a high aspect ratio (tall and thin) both Reynold’s number and contact time can be optimised.