The effective diffusion coefficient of the binary gas pair, hydrogen and nitrogen, has been measured for diffusion through several types of porous solids. Electrical conductivities through the pore spaces of the same solids were also measured with a view towards testing the analogy between ordinary diffusion and electrical conductivity. The results obtained show some discrepancies (up to 25%) from exact equivalence, especially in porous solids with a mean hydraulic diameter of less than 1 micron. The diffusion apparatus was also used to determine the temperature dependence of the ordinary diffusion coefficient in the range 20 - 300°C. The results obtained show close agreement with the Hirschfelder, Bird and Spotz theoretical equation for non-polar gas pairs. The data were also compared with other values reported for this system and good agreement was found. It is therefore concluded that the flow apparatus used is satisfactory for the investigation of the temperature dependence of the binary diffusion coefficient. Calibration of the apparatus at one temperature will yield satisfactory absolute values for binary diffusion coefficients at other temperatures. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

Union Carbide Canada Limited is one of four major industrial gas suppliers in Canada. Recently this firm contemplated entering the precision gases market as a supplier. However, lacking any detailed knowledge about this market, Union Carbide decided to have a market study made in order to provide the necessary information for planning a marketing program. This thesis presents a study of the precision (or specialty) gases market in British Columbia, an analysis of the findings, and a suggested approach to the marketing of precision gases in B.C. From information obtained from Union Carbide it was evident at the outset that precision gases are of a very specialized nature, and that total market demand for this type of product is limited compared to that for industrial gases. The company also indicated that the activities and interests of precision gas users are widely diversified. Because of these factors it was decided that a market survey should be conducted to determine some of the market characteristics, and that the survey should be conducted over 100 per cent of the known market population. Therefore, data was sought from all possible precision gas users in B.C., this data covering such points as: the particular gases being used; anticipated consumption; container requirements; and any expected changes in useage or in purchasing practices. Information was also obtained from some suppliers of precision gases in British Columbia. The data from the market survey were then studied to isolate pertinent market characteristics. It was soon confirmed that market demand is relatively small and users comprise a highly heterogeneous collection; forty-two users were found, ranging from small local businesses to giant international corporations, representing the fields of education, medicine, research and manufacturing. Market demand was found to cover a broad spectrum of product types--a total of seventy-five different gases are ordered in over two-hundred different ways most of them in very small amounts. However, further analysis of the data also revealed that of the 142,900 cubic feet of precision gases expected to be consumed in B.C. in 1969, 73 per cent is comprised of atmospheric gases and gas mixtures, most of which Union Carbide already handles for the industrial market; it also revealed that of these two types of precision gases, 96 per cent is used in standard industrial sized cylinders already used by Union Carbide. Thus by isolating those users purchasing atmospheric and mixed gases in industrial sized cylinders, Union Carbide can identify 70 per cent of the total market volume as a target market segment requiring a minimum of investment in new gases and facilities. Selection of channels of distribution for serving the above target market lead to consideration of the geographical density of the market population, and of the nature of the products and potential customers in question. It was decided that Union Carbide's existing direct-sales and distributor-sales forces are better suited to give effective sales coverage to this target market than any other alternative channels available to the company. The conclusion was, therefore, that Union Carbide should make use of its existing marketing organization to aim at the market segment using atmospheric and mixed gases in standard industrial sized cylinders. / Business, Sauder School of / Graduate

Hexagonal close packed and cubic close packed structures of heavy rare gas atoms are compared. Lattice expansion effects are examined for a model in which atoms interact via Lennard-Jones (12-6) potentials, lattice motion is according to the quasiharmonic approximation, and the model crystals are in equilibrium at constant temperature and pressure. Phonon frequencies are found to depend sensitively upon lattice parameters. In the cubic (hexagonal) structure the phonon modes most strongly affected by expansion are long (short) wavelength, longitudinal (transverse), acoustic (optic) modes. Phonon frequencies for the cubic structure all remain real for expansions considerably greater than would cause imaginary frequencies for the hexagonal structure. Equilibrium lattice parameters are found to deviate from their static equilibrium values by amounts depending upon the De Boer parameter, the deviations being slightly greater for the hexagonal structure, which exhibits nonideal stacking. The problem of explaining the observed stability of the cubic structures of real rare gas solids is discussed. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

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Thesis (Ph. D.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Aug. 31, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Engineering, Department of Chemical and Materials Engineering, University of Alberta." Includes bibliographical references.

Thesis (M. Sc.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 71-73).