Methods of processing large grained textured superconductor have been successfully developed, based on a melt texturing process. Large grained textured superconductor with grain size over 10mm along the growth direction and Jc over 3600A/cm² (77K, 0.5 Tesla) has been produced in both one - zone and two - zone furnaces with good reproducibility. Two kinds of design of reactive metal contacts have been proposed and investigated, aiming to make low resistivity contacts with strong mechanical strength. Three possible reactive contact metals have been tested for contact making, and the microstructures at the interfaces have been studied to find the relations between contact resistivity and contact processing conditions. Titanium/noble metal multilayer contacts is a promising type of contact technique for low resistivity and strong mechanical bonds. Gold and silver contacts give resistivities among the best reported results in the literature, and they turned out to be extremely stable in time, could withstand repeated thermal cycling from room temperature to 10K and yield very reproducible R-T curves. The electrochemical titration method has been used to increase the oxygen stoichiometry of bulk textured YBa₂Cu₃O_7-x samples. The electrochemical titration method can further oxidize melt textured thick film YBa₂Cu₃O_7-x samples in which it may be difficult to further improve oxygen content by conventional annealing. The solid state electrochemical cell has been used to study the thermodynamic properties of the Y-Ba-Cu-O system at high oxygen pressure by measuring the oxygen activity versus time continuously immediately after the electrochemical titration. A series of computer models have been set up according to the microstructure of the contact interface to simulate the complicated contact resistivity behaviours. The nature of, and geometry of, the reaction products at the contact interfaces may be revealed by the temperature dependence of the contact resistance. This information combined with direct observations on the structure and chemistry of the contacts provided a fuller understanding of conduction mechanism at the contact interface.

High-temperature processing of rice needs close attention due to the susceptibility of rice grains to fissures. The present study was carried out to redress the lack of information on the quality of rice dried at high-temperatures using a range of drying air temperatures from 160 - 200??C and grain moisture contents varying from 27 to 33%wb. A laboratory type high temperature dryer-oven was developed and constructed, and the performance was compared with commercial fluidized-bed and spouted-bed dryers. The new column type treatment plant, targeted at small-scale rice farmers was designed to reduce milling breakages was tested for high-temperature treatments. Short term drying (160 ??? 180 seconds) of high moisture rough rice at high-temperatures such as 160 - 200??C increased head rice yield by 5 - 8% in long grain rice and 7 - 11% in medium grain rice. The head rice yield increase achieved was very close to the highest potential head rice recovery possible for a given sample. The head rice yield increase was mainly due to a hardened surface layer of the rice kernel, formed by two effects, a surface fusion and surface gelatinization during high-temperature treatment. This stress protection layer is only effective for a short period (1 - 2 minutes) at high temperatures. Tempering of treated grains, either by storing in gunny bags or rapid cooling, can secure the grains to some extent from grain breakage. The highest head rice yield increase was obtained by ceasing the high-temperature effect at the grain moisture level of 24 - 25%wb. The colour and appearance of high-temperature treated grains were closer to those of untreated grains with the toughness closer to that of parboiled rice. The setback values of high-temperature treated rice measured by RVA, which is a preferred character by consumers, were closer to aged rice. High-temperature treatments did not affect the cooking qualities except a slight increase in water absorption. The alterations in the grain due to high-temperature treatment are limited to only for 8 - 9% of the total volume (mainly outer region) of the rice grain, preserving more than 90% of the grain with raw-rice quality. Structural changes such as complexing of amylose ??? lipid, amylose -protein and denaturation of protein play a dominant role on quality changes than gelatinization. A new method introduced to measure the degree of gelatinization of pre-gelatinized rice, using hot paste viscosity by rapid visco analyser (RVA), was successful. The peak viscosity parameter in the RVA was more suitable for measuring the chemical changes in high-temperature treated rice. Spouted-bed drying technology is not suitable for high-temperature treatment due to the unfavourable conditions for the formation of a hardened layer under intermittent heating and cooling. Fluidized-bed dryers could be used for high-temperature drying, but is not cost effective for the small-scale farmer level. The novel type treatment plant was successful in reducing the amount of broken grains to almost zero, increasing the head rice yield by 50 - 120kg per 1000kg of rough rice. It was also effective as a germination arrester, inhibiting the germination ability within a very short period such as 30 - 60 seconds. This equipment is more effective as a treatment Plant as it reduces moisture by only 1.5 - 2.0% at highest head rice yield recovery. An empirical model was successfully established (R2 = 0.99) for grain moisture content (db) and drying temperature during high-temperature processing. In model validation process, a good agreement was found between predicted and experimental data. The modelling between head rice yield and high-temperature drying was unsuccessful (R2 = 0.89) mainly due the interference from other factors such as initial moisture stress due to re-wetting and uncontrolled post treatment drying environment conditions. The study revealed some breakthrough for the rice industry in addition to its quantitative evaluation of increase in head rice yield. 1. Ability to produce grains with twice the toughness of milled untreated rice, without losing colour and appearance. 2. Fissured grains, previously weakened due to moisture-stress (considered as a loss), can be successfully recovered by treating this high-temperature technique. Currently there is no method available to increase the head rice yield of this type of fissured grains except parboiling, which is not widely accepted among consumers. 3. Drying at 200??C drying temperature completely destroyed the viability of seeds within 40 -60 seconds, hence providing a remedy for germination problems in wet harvests. 4. Since high-temperature drying needs wet rough rice, early harvesting can be done which will reduce shattering losses. This enable the farmers to use the field for an inter-seasonal crop which can utilise higher residual soil moisture in the paddy fields compared to other crops.

Thesis (MScIng)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Thesis (Ph.D) -- McMaster University, 1997. / Includes bibliographical references (p. 157-172). Also available via World Wide Web.

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (p. 194-202). Also available via World Wide Web.

Thesis (Ph.D.) -- McMaster University, 1999. / Includes bibliographical references (p. 94-111). Also available via World Wide Web.

Thesis (Ph.D.) -- McMaster University, 1997. / Includes bibliographical references Also available via World Wide Web.

Thesis (Ph.D.) -- McMaster University, 1997. / Includes bibliographical references (leaves l05-110). Also available via World Wide Web.

Thesis (Ph. D.)--Lehigh University, 1998. / Includes vita. Bibliography: leaves 201-223.

Thesis (Master)--İzmir Institute of Technology, İzmir, 2006 / Keywords: Superconductivity, bolometer. Includes bibliographical references (leaves. 74-78).