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The work explains how the dynamics of the release of water vapors from flux during the Control Atmosphere Brazing influences the process conditions important for the quality of the brazed product. The process involves sequential events such as continuous ramp-up heating, flux and filler melting, reactive flow, isothermal dwell and rapid quench solidification performed under the controlled atmosphere. During this complex process effluents are released. Some effluents are detrimental for the product quality (water vapor) and some are harmful for the environment (HF). We selected to study water vapor emissions with an objective to quantify these emissions and to consider their influence on the manufacturing process. Experiments were conducted using different fluxes. Findings are presented to compare the vapors released in each case. The objective is not necessarily to develop a metric for sustainability, but to understand the kinetics of an effluent release. A simple predictive model has been devised to approximate experimental data behavior. The data from the TGA analysis obtained from other sources, and the dew point temperature history from the controlled atmosphere brazing experiments performed in course of this work, have been used for the purpose of comparison and analysis.

One of the remaining problems associated with the photo-degradation of organic species in the atmosphere, is concerned with the mechanisms of C₅ and larger fragments. In this respect the 2-pentoxy radical has been chosen as a model radical. The subsequent mechanisms for it are thought to be similar to those for all other larger species. The photolysis of 2-pentyl nitrite in the near ultraviolet (UV) region at 328-383 nm resulted in the formation of 2-pentoxy radicals and nitric oxide with the quantum yield of 0.97 ± 0.08 at 298-393K, consistent with the assumption that the quantum yield was unity for alkyl nitrites. In the present work, <I>tert-</I>butyl nitrite has been shown to be unity. The reactions of the model radical were investigated in inert (CF₄), and oxygen atmospheres, by end product analysis using on-line gas-liquid chromatography. The expected reaction routes were: decomposition, oxidation (β-H atom abstraction), and 1,5-H shift isomerisation which would produce acetaldehyde, 2-pentanone and acetone respectively. Its reaction scheme was evaluated by comparing the experimental with model results, derived by the Gear Algorithm. The estimated or calculated rate constants in the literature were "brute force" adjusted to adapt the modelling results to the experimental results. Our investigations suggested, among the rate constants for the 2-pentoxy radical: k_dec9.2 x 10³s^-1: CH₃CH(O)(CH₂)₂CH₃ → n-CH₃CHO + n-C₃H_7,k₀₂ 7.0 x 10⁵M^-1s^-1: CH₃CH(O)(CH₂)₂CH₃+0₂ → CH₃C(O)(CH₂)₂CH₃ + HO₂, and k_isom 1.4 x 10⁴s^-1; CH₃CH(O)(CH₂)₂CH₃ → CH₃CH(OH)(CH₂)₂CH₂) The 1,5-H shift isomerisation is relatively fast. The Arrhenius parameters of these rate constants were also modified.

ix, 146 leaves : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1972)--University of Adelaide, Dept. of Physics, 1972

viii, 166 leaves : ill. ; 27 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 Physics, 1973

Thesis (Ph. D.)--University of Washington, 1989. / Vita. Includes bibliographical references.

Thesis (M. Sc.)--University of Adelaide, Dept. of Physics, 1985. / Includes bibliographical references (leaves 74-78).

Thesis (Ph.D. 1974) from the Dept. of Physics, University of Adelaide.

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution. / Includes bibliographical references (p. 186-188).

Thesis (Ph.D.) in Earth Sciences--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 106-129).