Thesis (M.S.)--Middle East Technical University, 2003. / Keywords: Ethyl methacrylate, atom transfer radical polymerization, gamma irradiation, free radical polymerization, viscosity.

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Current theories of the effects of static and resonant high frequency magnetic fields on radical pair reaction are presented with a view to establishing how they can form the basis of the high time resolution liquid phase magnetic resonance techniques of MARY and RYDMR. Approximate calculations are performed to reveal RYDMR spectral details for the case of an initial triplet radical pair. The design of unique apparatus to explore the capabilities of the techniques, and routinely collect quantitative data to test theoretical predictions, is described. This includes the development of an ultra-fast waveform scan-digitizing facility which can attain effective sampling rates of up to 20 GHz. The apparatus is employed to provide the first demonstration of recombination exciplex fluorescence from pyrene - dicyanobenzene radical-ion pairs. It is also applied in the dimensional characterization of micellar and microemulsion media prior to their use in enhancing MARY and RYDMR signal intensities from solubilized radical pairs. By means of a laser induced radical fluorescence technique and compartmentalized reaction media, first observations are reported of optically detected RYDMR spectra from neutral radical pairs, the existence of very low field MARY spectral structure and the kinetic effect of a resonant microwave field. The MARY structure is attributed to Heisenberg exchange interaction and shown to be sensitive to microreactor volume.

The chemical aging of organic aerosols by OH-initiated heterogeneous oxidation was investigated using both model organic and ambient aerosol particles. Organic aerosol particles were exposed to OH radicals in an aerosol flow tube and the modification of their chemical composition and particle properties was studied. Overall, this work has shown that OH-initiated heterogeneous oxidation enhanced the degree of oxidation and the Cloud Condensation Nucleus (CCN) activity of organic aerosol particles for equivalent OH exposure timescales of a few days to a week. Aerosol Mass Spectrometer (AMS) measurements showed that the heterogeneous uptake kinetics of OH radicals onto model primary organic aerosols was efficient. The heterogeneous reaction of organic aerosols with OH led to the production of high molecular weight particle-phase species with the addition of multiple oxygenated functional groups. These results were consistent with the observed increase in particle density with OH exposure. With the exception of solid organic aerosols, the particle volume and mass of organic particles were reduced by less than 20% from OH oxidation at high OH exposures due to volatilization of particle-phase reaction products. The degree of oxidation of the organic fraction of urban ambient aerosols was significantly enhanced for an equivalent atmospheric OH exposure time of 4 days for a daily average atmospheric OH concentration of 2×106 cm-3. Ambient aerosol particles sampled from a sparsely populated, forested region were initially more oxygenated than the urban aerosol particles and did not become more oxidized from reaction with OH radicals. The modification of the hygroscopicity of model primary and secondary organic aerosols from chemical aging was investigated by measuring the CCN activity of organic aerosols exposed to OH radicals. Primary organic aerosols, initially CCN inactive, became as CCN active as secondary organic aerosols due to heterogeneous reaction, where surface tension reduction played a major role. The CCN activity for model secondary organic aerosols was also enhanced due to OH oxidation, but changes were less dramatic than for the model primary organic aerosols.

[Typescript] / Includes bibliography. / 178 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 Organic Chemistry, 1966

Typescript (photocopy) / vi, 219 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 Organic Chemistry, 1982?

v, 174 leaves ; 26 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 Organic Chemistry, 1974

iii, 251 leaves : ill. ; 31 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 Organic Chemistry, 1980

v, 174 leaves ; 26 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 Organic Chemistry, 1974