No description available.

In this thesis, we focus on the properties of Al-doped ZnO (AZO) thin films for opto-electronic applications. AZO films were prepared by radio-frequency sputtering on silicon and optical glass substrates with 98wt% ZnO and 2wt% Al2O3 alloy target. AZO films were prepared under various deposition parameters (RF power, background pressure, Ar flow, and substrate temperature). The optimal parameters for the conductive and transparent AZO films are power = 100W, pressure = 3mTorr, Ar flow = 5sccm, and substrate temperature 250¢J. The film exhibits the resistivity(£l) of 2.5¡Ñ10-3 Ω-cm and 85% transparency in the 400-1800nm range. To find out optimum substrate temperature for the AZO film on p-GaAs (p=2¡Ñ1018), the samples were deposited at various temperatures followed by annealing at 400¢J for 30sec. The current-voltage (I-V) characteristics were measured. AZO films make good ohmic contact to p-GaAs to act as an electrode layer. InGaAs quantum-dot solar cells of AZO contact layers have been fabricated. A high filling factor of 52% is achieved.

No description available.

The goal of this thesis was to create a novel stable water-soluble azo polymer with photoswitchable properties, which was to be used as a scaffold in directing neuron growth. The new polymer, PDR2, was synthesized and extensively characterized to understand its physical and chemical properties, as well as to ascertain the structure. Characterization techniques included nuclear magnetic resonance, thermogravimetric analysis, differential scanning calorimetry, absorption spectroscopy, and ellipsometry. The photoresponsive properties of the polymer were then studied by examining quantum yields and birefringence, and the variation of these properties with humidity was examined, after being deposited onto thin films using layer-by-layer self-assembly. Quantum yields were found to increase with humidity up to a maximum determined to be at approximately 30% relative humidity, and were then found to decrease with increasing humidity. This was thought to be due to a combination of factors including plasticization and the formation of water clusters. Birefringence experiments revealed that the thin films did not produce a stable birefringence state. Many factors, including low azo content in the polymer, interaction with polymer side groups, and the mobility of polyelectrolyte multilayers were thought to contribute to these results.

No description available.

Diazotisation and aso=coupling reactions have been studied and the results are reported. A kinetic study of the acid catalysed diazotisation of various aniline derivatives has been made. The substrates considered were 2,4-dinitro-aniline, 4-nitroaniline, sulphanilaraide (aniline-4-sulphonamide) and sulphanilic acid (aniline-4-sulphonic acid). A new pK(_a) value of l.4 is reported for sulphanilamide. A study of the diazotisation of sulphanilic acid and sulphanilamide in the presence of Cl¯, Br¯, SCN¯, and SC(NH(_2))(_2) shows that the general catalytic trend Cl¯ < Br¯, SCN¯ < SC(NH(_2))(_2) is followed; whereas for the corresporaing nitrosating agents the general reactivity trend NOCl > NOBr >; NOSCN >NOS(^+)C(NH(_2))(_2) is followed. No catalysis was observed in the case of 2,4=dinitroaniline and this has-been interpreted in terms of a rapid reversible nitrosation in which the rate of the denitrosation step is greater than the rate of decomposition of the intermediate nitrosammonium ion. The bimolecular rate constants obtained for sulphanilic acid and sulphanilamide approach the diffusion controlled limit for this process in the case of NOCl and NOBr, Also reported is a study of the diazotisation of two heteroaromatic amines: 2-amino-5-nitrothiazole and 3-amino-l,2,4-triazoleo Catalysis by acid and the nucleophiles Cl¯ and SCN¯ has been observed. The catalytic and reactivity trends described above have been noted for reaction of these heteroaroraaticso The Pk(_a) value for 2-amino—5-nitrothiazole has-been determined and agrees well with the literature values. In addition to the above studies of diazotisation mechanisms, results are reported of a study of the leaving abilities of various electrofugal leaving groups X during ipso=coupling of 4=nitroaniline with 4-X,N- dimethylanilineso The sequence of leaving abilities has been determined by product yield studies. Rate constants for attack of ArN(^+)(_2) have also been determined. It is suggested that a substrate molecule (X-Ar-NMe(_2)) acts as a base in removing the group X from the Wheland intermediate.

Typescript / 157 leaves and 1 reprint / 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

vi, 322 leaves : ill., bibliog. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1972) from the Dept. of Organic Chemistry, University of Adelaide

Thesis (Ph.D. 1972) from the Dept. of Organic Chemistry, University of Adelaide.

Thesis (Ph.D.) -- University of Adelaide, Dept. of Organic Chemistry, 1966. / Typescript.