Ionic liquids (ILs), consisting of ions that are liquid at ambient temperatures, can act as solvents for a broad spectrum of chemical processes. These ionic liquids are attracting increasing attention from industry because they promise significant environmental as well as product and process benefits. ILs were used as solvents for two industrially important homogeneous reactions namely metathesis of 1-octene and the hydroformylation of vinyl acetate. In the metathesis of 1-octene, several reaction parameters were investigated, including temperature, catalyst (type and concentration) and influence of ionic solvent and conventional solvents. Temperature and catalyst concentration were found to be rate-determining factors, but played smaller roles in determining the outcomes of the reactions compared to the influence of individual ILs. It was discovered that more polar ILs were favourable in producing high rates and selectivities. Imidazolium-based cations and tetrafluoroborate anions were superior in activity when compared to other combinations of cations and anions. The addition of catalyst promoters such as phenol and tin(II) chloride were also investigated and found to enhance metathesis rates in “neat” reactions. These catalyst promoters inhibited metathesis rates when used in combination with ILs. In the hydroformylation of vinyl acetate, several reaction parameters were investigated, including temperature, catalyst concentration, vinyl acetate concentration, ligand concentration, syngas pressure and influence of ionic solvent and conventional solvents. It was shown that high n : i ratios of aldehyde products were formed with specific IL systems. Also, low ligand concentrations and low vinyl acetate concentrations increased selectivities, although rates of reactions were somewhat compromised. Lower syngas pressure and lower temperatures afforded enhanced selectivities, again at the expense of reaction rates. Depending on whether fast reaction rates or high regioselectivity is required, the IL and general reaction conditions can be tailored to fit the needs of the reaction. It was discovered that aromatic-containing ammonium-based ILs v afforded high rates at low selectivity. Bulkier ammonium cations tended to give lower rates but the selectivity was significantly enhanced. Impurities present in ILs have also been shown to have a marked effect on hydroformylation rates and selectivity. The reader will be accompanied along a path designed to discover an optimised set of reaction conditions, the path of which will take the reader from reactions providing low selectivities, low turnover numbers and low yields to a much brighter picture, namely extremely high selectivities, turnover numbers and yields. / Prof. D.B.G. Williams

Class of 2013 Abstract / Specific Aims: To determine if temperature and direct sunlight influence the rate of evaporation of normal saline in 100mL IV bags. Methods: Four study groups were created; refrigeration, dark shelf, shelf near window, and EMT box simulation. 80 bags (50 ml bags of normal saline) placed in different areas of temperature change and sun exposure. 20 of the bags stored in a drawer in a refrigerator. 20 stored on a shelf in a dark temperature controlled room. 20 stored next to a window in direct sunlight, and 20 stored outside where temperature and sun exposure will be highest in an EMT simulated box. Weights were recorded (in gms) weekly for 8 weeks using an analytical balance. Each saline bag was weighed individually and recorded at the time of measurement. Main Results: Rates of volume loss were lower in the normal saline IV bags stored in a refrigerated environment compared to the other two groups stored at room temperature and the one group stored in outside conditions (p<0.001). IV bags stored at room temperature exposed to light had the second lowest rate of loss compared to the other two groups (p<0.001 compared to outside conditions and p=0.003 compared to closed drawer). Bags stored at room temperature in a closed door had the third lowest rate of loss (p<0.001). Conclusion: Rate of fluid loss from IV normal saline bags appears to be temperature sensitive and storage of these bags may have an impact on shelf life of the product.

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The classical existence theorem for the steady Navier-Stokes equations, based on a bound for the solution's Dirichlet integral, provides little qualitative information about the solution. In particular, if a domain is unbounded, it is not evident that the solution will be unique even when the data are small. Inspired by the works of Odqvist for the interior problem and of Finn for the problem of flow past an obstacle, we give a potential theoretic construction of a solution of the steady Navier-Stokes equations in several domains with noncompact boundaries. We begin by studying a scalar quasilinear elliptic problem in a half space, which serves as a model problem for the development of some of the methods which are later applied to the Navier-Stokes equations. Then, we consider Navier-Stokes flow in a half space, modeling such phenomena as a jet emanating from a wall, with prescribed boundary values. The solution which is obtained decays like |x|⁻² at infinity and has a finite Dirichlet integral. Finally, we solve the problem of flow through an aperture in a wall between two half spaces, with a prescribed net flux through the aperture, or with a prescribed pressure drop between the two half spaces. A steady solution is constructed which decays like |x|⁻² at infinity. For small data, uniqueness is proven within the class of functions which decay like |x|⁻¹ at infinity and have finite Dirichlet integrals. / Science, Faculty of / Mathematics, Department of / Graduate

The equilibrium constant for the dissociation of the BeF₄˭ ion in aqueous solutions of the ammonium salt has been computed by using the intensities of the fluorine nuclear magnetic resonance signals to indicate the concentrations of the three species at equilibrium. The simple dissociation may be represented as; BeF₄˭⇢ BeF₃¯+ F¯ (i) KE = 8.0 ± 0.9 x 10¯²moles (Kg)¯¹at 33°C. The equilibrium was measured over the temperature range 0-50°C but no appreciable temperature coefficient was observed. Variation of the concentration of BeF₂ solution allows the identification of further resonances, which have been associated with the unionized BeF₂ and a possible existence of a BeBeF₄ species. Chemical shift changes in the ⁹Be nuclear resonance positions are minimal. Some suggestions are made regarding the kinetics of fluorine exchange in reaction (i). The large changes in ¹¹B-¹⁹F coupling constant and ¹⁹F chemical shift of BF₄¯ ion at different concentration in aqueous and mixed solvents (acetone/water, dioxane/ water and D.M.S.O./water) have been interpreted in terms of changes in the hydrogen bonding of water to the BF₄¯ ion. The unique behavior of chemical shift and coupling constant in D.M.S.O./water has been explained by preferential solvation of BF₄¯ ion by the protolysis product of D.M.S.O. in water. The concentration dependence of the fluorine chemical shift of diamagnetic salts of fluoroanions of the type F¯, BF₄¯ and SiF₆˭ have been studies and the molal chemical shift has been correlated with the size and the charge of the cation. A displacement of the fluorine chemical shift to low field was observed for F¯, BF₄¯, BeF₄˭, PF₆¯ and SiF₆˭ aqueous solutions with paramagnetic cations Cu⁺⁺, Ni⁺⁺, Co⁺⁺, Fe⁺⁺, Fe⁺⁺⁺, Cr⁺⁺⁺ and Mn⁺⁺. These shifts are explained on the basis of ion-pair formation between cation and fluoroanion. The molar shifts have been interpreted in terms of a contact interaction between unpared electron and ¹⁹F nucleus. The contribution due to Pseudo contact shift, which arises due to anisotropy in g-factor is probably small. The changes in ¹⁹F line width with the concentration of paramagnetic ion have been discussed in the light of exchange between freee and ion-paired fluoro-anion. Further evidence regarding the ion-pair formation in f luoro-borates has been obtained from ¹¹B chemical shift and line width measurements. ¹⁹F N.M.R. spectra of HF₂¯ ion of Na⁺, K⁺ and NH₄⁺ cations have been studied, and the equilibrium constant for the reaction HF₂ ⇢ HF + F¯ (ii) have been measured for the potassium salt. Preliminary investigations of different gallium fluoride complex in mixtures of AgF and Ga(ClO₄)₃ have been made / Science, Faculty of / Chemistry, Department of / Graduate

This thesis investigates the viability of two boundary element methods for solving steady state problems, the continuous least squares method and the Galerkin minimization technique. In conventional boundary element methods, the singularities of the fundamental solution involved are usually located at fixed points on the boundary of the problem's domain or on an auxiliary boundary. This leads to some difficulties: when the singularities are located on the problem domain's boundary, it is not easy to evaluate the solution for points on or near that boundary whereas if the singularities are placed on an auxiliary boundary, this auxiliary boundary would have to be carefully chosen. Hence the methods studied here allow the singularities, initially located at some auxiliary boundary, to move until the best positions are found. These positions are determined by attempting to minimize the error via the least squares or the Galerkin technique. This results in a highly accurate, adaptive, but nonlinear method. We study various methods for solving systems of nonlinear equations resulting from the Galerkin technique. A hybrid method has been implemented, which involves the objective function from the least squares method while the gradient is due to the Galerkin method. Numerical examples involving Laplace's equation in two dimensions are presented and results using the discrete least squares method, the continuous least squares method and the Galerkin method are compared and discussed. The continuous least squares method appears to give the best results for the sample problems tried. / Science, Faculty of / Computer Science, Department of / Graduate

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Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

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