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The object of the research described in this thesis is to provide, by means of laboratory experiments, data required to understand the atmospheric chemistry of the nitrate radical, from both a mechanistic and kinetic point of view. The low pressure discharge-flow kinetic technique coupled detection of the NO₃ radical by optical absorption was used to measure the temperature-dependent rate coefficients for the reaction of NO₃ with 1-butene, 1-chloro-l-butene, 2-chloro-2-butene, 3-chloro-l-butene, 1-chloro-2-butene, 2-chloro-2-butene, 1-chloromethylpropene, 3-chloromethylpropene, 3-bromo-1-butene, 4-bromo-l-butene and 2-bromo-2-butene. The atmospheric implications for the reaction of NO₃ with these compounds are discussed. In order to understand the patterns of reactivity towards NO₃ exhibited by these compounds, a number of approaches were adopted. First, a non-quantitative approach employing the simple ideas of inductive and mesomeric effects. Secondly the observed reactivity of NO₃ towards these compounds was discussed, quantitatively, in terms of the relative energies of the interacting orbitals. This quantitative analysis required an extensive set of molecular orbital calculations were undertaken at various levels of sophistication. A good correlation was found, for compounds not containing vinylic halogen atoms, between -E(HOMO) and the measured rate constant; the data were used also to calculate "group-reactivity factors". In an extension to this work a new empirical correlation is presented that takes account of the contribution, in terms of the atomic orbital coefficients, of vinylic halogen atoms to the observed rate constant. To provide support for these calculations, work was undertaken using photoelectron spectroscopy to characterise experimentally the individual molecular orbitals. A correlation between the inverse of the molecular polarisability and the activation energy of the reaction is also described. Complementary work was undertaken in a unconventional flash-photolysis system to look at the kinetics of the reaction NO₃ + NO₃ andlongrightarrow; 2 NO₂ + O₂ over a pressure range of 2 to 100 Torr in helium. The measured rate coefficient was found to be pressure independent and to have a value of (2.2±1.0) x 10^-16 cm₃ molecule^-1 s^-1. The experimental work on the nitrate radical was extended to look at the laser-induced fluorescence (LIF) spectrum and at the quenching of the excited state of the nitrate radical.

The channel flow method has established the net dissolution kinetics of calcite single crystals at high pH (7.7-9.7) and varying bulk Ca²⁺ concentrations (0-10 mM), using wide ranges of solution flow rates (10^-3-0.3 cm³ s^-1). Literature rate equations were in poor agreement with experiment. Modelling with the following mechanism, where Ca²⁺ and CO₃^2- undergo Langmuirian adsorption: Ca²⁺_(aq) ⇄ Ca²⁺_(ads) CO^2-</sub>3 (aq)</sub> ⇄ CO^2-_{3 (ads)} Ca(sup>2+</sup></sub>(ads)</sub> + CO^2-_{3 (ads)} ⇄ CaCO_{3 (ads)} CaCo_{3 (ads)} → CaCo_{3 (lattice)} and the consequent rate law J_net/mol cm<sup>-2</sub>s^-1 = k_pK_CaK_CO₃ {K_sp - [Ca²⁺]_o[CO^2-₃]_o (1 + K_Ca[Ca²⁺]_o)(1 + K<sub>CO₃[CO^2-₃]_o) gave excellent agreement with experiment under all conditions studied. This mechanism is shown to explain all literature streaming potential, electrophoresis and kinetic salt effect data. Dissolution of calcite under the above conditions was strongly inhibited by Mg²⁺ and fully deprotonated forms of succinic acid, 2-sulphobutanedioic acid, phthalic acid and maleic acid. Mechanisms were established; for the maleate dianion, the inhibition was due to the blocking of the dissolution sites at which CaCO₃ units are incorporated into the crystal lattice. For the other ions, inhibition arose from competitive Langmuirian adsorption either between CO₃<sup>2-<sup> and the anions, or between Ca²⁺ and Mg²⁺. A new method to quantify the inhibited dissolution of particulate CaCO₃ (=10 μm) via enhanced mass transport of solution to the rotating disc electrode, due to the rotation of the particles in the diffusion layer, has been established. Good agreement was found with that measured independently using the channel flow cell. A.c. impedance spectroscopy has been used to characterise scaled (CaCO₃) steel tubes. Results provide scope for (i) monitoring scale growth, and (ii) use in safety control devices for alerting to the scaling of pipe-work.

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Bibliography: leaves 178-210. / xiii, 230 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis examines the effects of endurance exercise training on whole body blood lactate removal, and the production and removal of blood lactate by skeletal muscle. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 1997?

Includes bibliographical references / 125 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1969

Typewritten / Includes bibliographical references / 232 leaves ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1964