Polarized Raman spectroscopy has been used to measure the deuterium isotope effect, (delta)pK = pKD2O – pKH2O, for the second ionization constant of sulfuric acid in the temperature range of 25 °C to 200 °C at saturation pressure. Results for pK in light water agree with the literature within ± 0.034 pK units at alltemperatures under study, confirming the reliability of the method. The ionization constant of deuterated bisulfate, DSO4-, differs significantly from previous literature results at elevated temperatures. This results in an almost constant (delta)pK ≈ 0.425 ± 0.076 over the temperature range under study. Differences in (delta)pK values between the literature and current results can be attributed to the effect of dissolved silica from cell components. The new results are consistent with (delta)pK models that treat the temperature dependence of (delta)pK by considering differences in the zero-point energy of hydrogen bonds in the hydrated product and reactant species. The phosphate hydrolysis equilibrium was measured between the temperatures of 5 °C and 80 °C and the borate/boric acid equilibrium between the temperatures of 25 °C and 200 °C. The high alkalinity and temperatures experienced by these two systems had a significant impact on the glass dissolution and equilibrium. / Raman spectroscopy was used to measure the small differences in ionization constants for weak acids/bases as a function of temperature. / University of Guelph, Atomic Energy of Canada Limited (AECL), Bruce Power, University Network of Excellence in Nuclear Engineering (UNENE), National Sciences and Engineering Research Council of Canada (NSERC), Natural Resources Canada, Ontario Power Generation (OPG), Canada Foundation for Innovation

Ice-associating proteins (IAPs) are proteins that interact directly with ice crystals, either by offering a site for nucleation, i.e. ice nucleating proteins (INPs), or by binding to nascent crystals to prevent addition of more water molecules, i.e. antifreeze proteins (AFPs). AFPs have been found to inhibit the formation of clathrate-hydrates, ice-like crystalline solids composed of water-encaged guest molecules. Study of AFP-hydrate interaction is leading to a greater understanding of AFP adsorption and of the mechanism behind the “memory effect” in hydrates, wherein previously frozen crystals reform more quickly after a brief melt. AFP is currently the only known memory inhibitor. Such a low-dosage hydrate inhibitor (LDHI) is of great interest to the oil and gas industry, as hydrate formation and reformation in the field is a huge problem. Bacterial AFPs, though largely uncharacterized, may be the best candidates for large-scale production of hydrate inhibitors, given the difficulties in obtaining AFP from other sources. The popular kinetic inhibitors (KIs) polyvinylpyrrolidone (PVP) and polyvinylcaprolactam (PVCap) were used for points of comparison in experiments exploring the hydrate-inhibition activity of several ice-associating bacteria and proteins. The addition of the soil microbe, Chryseobacterium, increased the average lag-time to tetrahydrofuran (THF) hydrate formation by 14-fold, comparable to PVP or PVCap. Samples containing Pseudomonas putida, a bacterium having both ice-nucleation protein (INP) and AFP activity, had lag-times double that of the control. Solutions with P. putida and Chryseobacterium sometimes formed hydrate slurries of stunted crystal nuclei instead of solid crystals. No inhibition of memory or nucleation was noted in bacterial assays, however bacteria with INP activity was linked to unusually rapid memory reformation. Quartz crystal microbalance experiments with dissipation (QCM-D) showed that a tight adsorption to SiO2 and resistance to rinsing are correlated with a molecule’s inhibition of hydrate formation and reformation. These results support a heterogeneous nucleation model of the memory effect, and point to the affinity of AFP for heterogeneous nucleating particles as an important component of memory inhibition. / Thesis (Master, Biology) -- Queen's University, 2008-05-30 15:20:38.749

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Nanoporous molecular sieve materials like metal organic frameworks (MOFs) and metal oxide nanotubes (AlSiNTs) have found a wide range of technological applications in catalysis, separations, and ion exchange due to their salient features over other contemporary sensing materials. As a result, these materials can function as a chemical recognition layer that relies on analyte adsorption and they have shown to selectively adsorb specific gas molecules from mixtures. The characterization of gas adsorption in these materials is performed predominantly by commercial gravimetric equipment, whose capital and operating costs are generally high and require relatively large amounts of sample. Thus, it is desirable to obtain a reliable measure of the gas transport properties of these materials over a substantial range of pressure and temperature by non-gravimetric methods. The objective of this thesis is to investigate the adsorption and diffusion characteristics of recently-identified nanoporous materials through the development and use of a high-pressure/high-temperature quartz crystal microbalance (QCM) device. In this regard, this thesis is divided into four main objectives, viz. (1) Design and development of high temperature/ high pressure QCM device, (2) Measurement and analysis of adsorption characteristics in nanoporous materials, (3) Diffusion measurement and analysis in polymer thin films and (4) Diffusion measurement and analysis in MOF crystals. The results obtained in Objectives 2-4 will allow us to make important recommendations regarding the use of specific nanoporous materials in molecular separation applications and also lead to significant understanding of gas uptake thermodynamics in nanoporous materials via the application of analytical models to the experimental data.

Organic electrical energy storage (EES) is a growing field of research that is expected to play an important role in the future, as the need for sustainable EES increases. Conducting redox polymers (CRPs), i.e. conducting polymers with incorporated redox active moieties e.g. as pendant groups (PGs), are proposed as a promising class of compounds for this purpose. Redox cycling of the PGs can be utilized for high charge storage capacity, while the conducting polymer backbone provides fast charge transport through the material. Some of the major challenges with small-molecule systems for EES could be solved by using CRPs, e.g. capacity fading due to dissolution of the active compound, and high resistance due to slow charge transport between molecules. The latter issue is often solved by adding large amounts of conducting additives to the active material, drastically lowering the specific capacity. In this project, CRPs are shown to be able to function in battery cells without any additives, making both high capacity and high power possible. Although several CRPs have been reported in the literature, very few detailed studies have been conducted on the electrochemical processes of the two systems (i.e. the conducting polymer backbone and the redox active PGs). An important factor to consider in CRP design is the possibility for interaction between the two redox systems, which could be either beneficial or detrimental to the function as EES material. In this thesis, CRP model systems composed of hydroquinone functionalized polypyrrole have been studied, and they exhibit separate redox reactions for the PGs and the backbone, overlapping in potential. Significant interaction between them was observed, as oxidation of the PGs has severe impact on the backbone: When the oxidized and hydrophobic p-benzoquinone PGs are formed, they pack and force the polymer backbone to twist, localizing the bipolarons, and decreasing the conductivity. This is accompanied by a contraction of the polymer film and expulsion of electrolyte. Overall, the interaction in these polymers is destructive for their EES function, and it could be eliminated by introduction of a long linker unit between the PGs and the backbone.

ABSTRACT ELECTROCHEMICAL HYDRIDE GENERATION AND ATOM TRAPPING ATOMIC ABSORPTION SPECTROMETRY FOR DETERMINATION OF ANTIMONY Menemenlioglu, ipek M.S., Department of Chemistry Supervisor: Prof. Dr. O. Yavuz Ataman June 2004, 82 pages Electrochemical hydride generation is a suitable alternative to common hydride generation by NaBH4 which is widely used for the detection of volatile elements such as As, Se, Sb, Sn, Bi, Ge, Te and Pb. In this study, a thin-layer flow through electrochemical cell was designed. Lead and platinum foils were employed as cathode and anode materials, respectively, for the generation of antimony hydride. Argon was used as the carrier gas. The inlet arm of the conventional quartz tube atomizer was used for on-line preconcentration of generated hydrides. A portion of the inlet arm was heated externally to the collection temperature for trapping the analyte species which were generated electrochemically. For the revolatilization of the trapped species, the trap was further heated to the revolatilization temperature and hydrogen gas was introduced into the system 10 seconds afterwards. The experimental operation conditions for electrochemical hydride generation which include the acidities and flow rates of catholyte and anolyte solutions, carrier gas flow rate and the applied electric current, were optimized. For trapping, collection and revolatilization temperatures and hydrogen flow rates were optimized. Analyses of standard reference materials were performed to check the accuracy of the proposed method. 3&amp / #963 / limit of detections were found as 1.03 ng ml-1 and 0.053 ng ml-1 with and without employing the trap, respectively. The trap has provided 20 fold sensitivity improvement.

The electric potential changes under uniaxial loading in some minerals and rocks have long been recognized. To daylight the electrical response of some minerals and rocks against applied stress, both theoretical studies and laboratory experiments are conducted. Some theories are also proposed by different researchers, in order to explain the electric potential variations. However, the mechanisms leading to electrical potential generation have not been fully explained yet. In the explanation of electric potential changes observed in rocks, type of the observed rock and the rock forming minerals in the rock fabric play an important role. One theory is based on the fundamentals of piezoelectricity only. However the relation between the stress state and the electric generation is not fully understood. This thesis aims to make a further contribution to the studies on understanding the electric potential change in rocks, containing quartz, which is a common piezoelectric mineral, under uniaxial loading conditions. Three types of rocks, namely quartz-sandstone, granite and granodiorite, are tested, and the stress and electric potential (EP) variations are recorded during the uniaxial loading experiments in a continuous manner. The experiments are conducted at three different loading rates, in order to investigate the effect of loading rate on the electrification mechanism. Also step loading experiments are conducted. Results indicated that, application of uniaxial stress creates a clear change in the EP responses of three quartz bearing rock types. The possible relationships between the EP generation and the level of applied stress are investigated based on the initial and final potential values (EPinitial, EPfinal), the potential just before the time of failure (EPUCS), the spike-like potential jump at the time of failure (&amp / #8710 / V), which are derived from the recorded data of the experiments.

The Great Bear magmatic zone, Northwest Territories, hosts numerous giant quartz veins and stockwork zones. These zones can be up to 100m wide and up to 10km long, with two or more generations of quartz. A few of the giant quartz vein zones host base-metal uranium mineralization, and some are proximal to mineralization, although most are barren. Cathodoluminescence imaging shows the quartz veins have complex growth zones and a trace element study suggests that these zones are the result of Al and Li substitution in the quartz lattice. Oxygen isotope (18Oqtz) values of quartz generally fall between +8 to +14.6 (VSMOW). Fluid inclusion homogenization temperatures range from 100 to 375C, and the fluids have variable salinities. The fluids that created the giant quartz veins are epithermal in nature with a meteoric water brine signature, and formed as a result of multiple fluid pulses and re-fracturing events.

Interactions between carbohydrates and proteins are increasingly being recognized as crucial in many biological processes, such as cellular adhesion and communication. In order to investigate the interactions of carbohydrates and proteins, the development of efficient analytic technologies, as well as novel strategies for the synthesis of carbohydrates, have to be explored. To date, several methods have been exploited to analyze interactions of carbohydrates and proteins, for example, biosensors, nuclear magnetic resonance (NMR); enzyme-linked immunosorbent assays (ELISA), X-ray crystallography and array technologies. This thesis describes the development of novel strategies for the synthesis of carbohydrates, as well as new efficient strategies to Quartz Crystal Microbalance- (QCM-) biosensors and carbohydrate microarrays technologies. These methodologies have been used to probe carbohydrate-lectin-interactions for a range of plant and animal lectins. / QC 20100915