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Changes in redox potential (Eh), major sulfur species and the solubility of selenium and boron in reduced flue gas desulfurization (FGD) sludge, when exposed to atmosphere were studied in laboratory experiments. Also the effect of organic carbon and temperature on reduction of FGD sludge and changes in concentration of major S species was studied. Stable isotopic ratios of sulfur and carbon compounds were used to investigate the possible pathways of S transformation in FGD sludge disposal site. Oxidation of reduced sludge appears to be a two step process, a fast step of chemical oxidation followed by a slow step of biological oxidation and is significantly affected by moisture content and mixing of the sludge. With the addition of organic carbon Eh of the FGD sludge dropped exponentially and reduction of sulfate initiated at Eh of about -75 mV and was maximum in the range of -265 to -320 mV. Temperatur8e of the profile and organic carbon appear to be the key factors affecting the rate and extent of reduction in flooded FGD sludge. Selenium solubility decreased four times as Eh dropped from 215 mV to -350 mV while boron solubility was unchanged in this range of Eh. Stable isotopic ratio of sulfate and sulfide are typical of bacterial reduction and suggest that only aqueous sulfate was being reduced. The low δ³⁴S values of CaSO₄ from the upper layers of profile indicate the production and upward movement of hydrogen sulfide gas in the FGD sludge.

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Low Emission Vehicles (LEVs) represent a car classification which utilizes advancements in automotive technology to address policy objectives associated with energy security and greenhouse gas emissions. The effectiveness of LEVs at addressing these objectives will not only depend on their technical performance but also on their levels of adoption by consumers. With LEVs encompassing cars which are significantly different compared to conventional market options, the understanding of consumer response to these vehicles remains limited. This thesis addresses this limitation in existing knowledge by providing a detailed examination of consumer demand for LEVs in the UK. Through the application of psychometric methods, this thesis assesses the influence of socio-psychological constructs over LEV preference. A bespoke conceptual framework has been developed to provide insights regarding the influence of attitudes, emotions and values. This framework was applied to the design of a self completion household questionnaire distributed over the cities of Newcastle upon Tyne and Dundee. The meanings placed on car ownership are measured alongside the concept of innovativeness to determine if these traits are likely to hinder or advance LEV adoption. Additionally, past research has tended to consider consumer demand for LEVs at a market level perspective with little attention given to social stratification. This thesis advances knowledge in this area by producing a structural analysis of the emerging market for LEVs. Noteworthy consumer segments are identified, described and compared according to their socio-psychological profiles, socio-economic characteristics and LEV preferences. Principle results of the thesis are that socio-psychological constructs account for a greater degree of variance compared to socio-economic characteristics when explaining evaluations of LEVs. The propensity to consider cars through symbolic, emotive and functional meanings tends to decrease assessments made concerning the functional capabilities of LEVs. The concept of innovativeness displays a positive influence over preferences towards LEVs indicating that these vehicles are being considered as innovations. Moreover, heterogeneous consumer segments with unique socio-psychological and demographic profiles are emerging in the LEV market. These segments display a range of LEV preference structures from those which hold high preferences and are likely to characterize early adopters to those which exhibit low preferences and are likely to represent non-adopters.

Two identical instruments have been developed for use in the field to make radiometric measurements. They have been described as spectropolarimeters because of their ability to make polarization measurements in narrow spectral passbands. They have been used as part of a NASA sponsored project to monitor the spectral and temporal response of the thematic mapper satellites. These satellites allow many natural and man-tended resources to be monitored over years of time, thus allowing their use to be planned for in the future. The dissertation discusses the design, fabrication, testing and absolute radiometric calibration of these spectropolarimeter instruments. The outstanding feature of these instruments are that they have been calibrated absolutely, for radiance measurements, to an accuracy of 2% - 3%, in the range of 400 nm to 1040 nm over selected spectral passbands. Previously, field measurements were considered good if they had an absolute accuracy of 10%, implying that the present accuracies are advancing the state-of-the-art for field instrument calibrations. These improved accuracies are the result of using two recently developed calibration standards, both of which use detector based methods. These standards are the Electrically Calibrated Pyroelectric Radiometer (ECPR), and the QED-100 quad detector. The end of the dissertation discusses the attempts made to verify that the accuracies claimed are indeed valid, and it is the author's belief that these accuracies have been verified completely.

published_or_final_version / Physics / Doctoral / Doctor of Philosophy

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