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This thesis describes the development of pre column derivatisation reactions for the selective determination of organic functional groups in oxidised oils by liquid chromatography (LC) with luminescence detection. The testing of oils for oxidative stability and the current methods of oil analysis are reviewed in chapter one. An overview of LC and luminescence spectrometry, with particular regard to chemiluminescence (CL) is also presented. Chapter two is a flow injection investigation of the experimental variables of the peroxyoxalate CL reaction. Two aryl oxalates; bis(2,4-dinitrophenyl)oxalate and bis(2,4,6-tricblorophenyl)oxalate were compared for their suitability to LC detection. A charge coupled device (CCD) was used to obtain the CL spectra of fluorophores and to investigate the CL emission background. Chapter three and four describes procedures for the determination of carboxylic acids in oils by pre column esterification with 9-anthracenemethanol, reversed phase LC and either peroxyoxalate CL or fluorescence detection. The oils were dialysed prior to derivatisation to remove high molecular weight species which were found to interfere with the reaction. Carboxylic acids were present in the oxidised oils and their concentrations reflected the degree of degradation of the oils. The determination of aldehydes in oxidised oils is described in chapter five. The aldehydes in oil dialysates are labelled by reductive amination with 3- aminofluoranthene and the derivatives separated by isocratic reversed-phase LC with peroxyoxalate CL detection using TCPO-hydrogen peroxide. Aldehydes were also found to be produced by the oxidation of oils in car engines.

This research continues the earlier researches on wear friction and lubrication and its application to the powder metallurgy industries. A detailed study of the parameters involved in wear and friction has been made by using the "Pin and Disc" machine with cross cylinders technique. One iron powder was chosen and compacted over a range of densities with a series of metallic stearates as admixed lubricants for the purpose of examinations. These compacts were used as the "pins" for the wear and friction apparatus, the "disc" was made from high carbon high chromium steel which is one of the steels normally used in punches and dies in the powder metallurgy industries. The wear behaviour of these compacts was studied in relation to the following parameters: applied load between compact (or pin) and disc, sliding speed, travelled distance, density and hardness of compact. These were examined for a range of stearate lubricants and the wear rates determined, these data were then related to the possible industrial life for punches and dies in powder metallurgy presses. Besides wear rate, friction forces between the compact (or pin) and disc were measured and these forces of friction were translated into coefficients of friction for each type of lubricant. The thesis presents the results of these investigations with a survey of current theories on wear and friction of metallic systems relevant to powder metallurgy. Conclusions have been drawn and suggestions made on the most useful solid lubricant necessary in the pressing of metallic powders to reduce wear and friction in production presses. Calculations have been carried out using the data collected to estimate the possible press tool wear and accordingly a possible tool life was determined for pressing with each type of ~tearate lubricant. The overall conclusion was that zinc stearate is the best solid lubricant in the five metallic stearates (Al, Na, Mg, Ca and Zn) for use in iron powder compaction.

To modify the rheological behaviour of rubber compounds, in order to improve their processing behaviour, lubricants based on fatty acid derivatives are added at the mixing stage. This research has been directed towards identifying the modes of action of commercially available lubricants in a number of elastomers and elastomer compounds, with the objective of providing a rational basis for the further development of lubricants. The primary tool for rheological measurement was an advanced biconical rotor rheometer (Negretti TMS Rheometer); and a capillary rheometer was used to provide an independent verification of results. Conceptual and mathematical models have been proposed which provide a rational explanation and simulation of lubricant action. The conceptual model takes account of elastomer morphology, relative solubility parameters of elastomer and lubricant and chemical reactions between the lubricant and elastomer in order to explain internal lubrication, chain extension/crosslinking, solvation and external lubrication. The mathematical model simulates the primary lubricant actions of internal lubrication and chain extension/cross-linking.

Thesis (PhD)--University of South Australia, 2003.

Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Neitzel, G. Paul; Committee Member: Allen, Mark G.; Committee Member: Degertekin, F. Levent; Committee Member: Schatz, Michael; Committee Member: Smith, Marc K.

Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1994. / Abstract. Includes bibliographical references (leaves 95-100). Also available via the Internet.

Inaug.-diss.--Eidgenössische technische hochschule, Zürich. / Lebenslauf.