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This thesis presents the research on the development and optimisation of energy efficient adsorbent monoliths and foam-monoliths for the removal of carbon dioxide (CO2) and other contaminants such as hydrogen sulfide (H2S) and water (H2O) vapour from the biogas stream. Zeolite and MIL-101(Cr) monoliths and carbonate-based zeolite foammonoliths of novel chemical formulations have been manufactured, characterised and tested for adsorption. Using the prepared adsorbent monoliths as models, their kinetic adsorption and gas flow dynamic performances have also been evaluated and compared with packed beds of commercially available adsorbent beads. The research mainly comprised of three parts. The first part was concerned with the manufacturing, characterising and optimising the adsorbent monoliths and foammonoliths. The adsorbent monoliths and foam-monoliths have been fabricated successfully using the unique paste extrusion technique described in this thesis. This includes monoliths of 13X zeolite, LiLSX zeolite, 5A zeolite, clinoptilolite and MIL-101(Cr) and foam-monoliths of K2CO3/13X zeolite and Na2CO3/13X zeolite. The incorporation of a decomposable pore former such as Licowax C micropowder PM into their paste formulations were found to improve their structural porosity, adsorption performance and mass transfer. It has been found that the best type of adsorbent structure for CO2 adsorption were 13X zeolite and purified MIL-101(Cr) monoliths and K2CO3/13X zeolite foam-monoliths. The CO2 adsorption performances of purified MIL-101(Cr) monoliths and K2CO3/13X zeolite foam-monoliths have been shown to be comparable to a packed bed of 13X zeolite beads (in terms of effectiveness of the adsorbent bed utilisation and equilibrium adsorption capacity on mass basis, respectively). This confirmed that the prepared adsorbent monoliths and foam-monoliths were potential adsorbent structures for CO2 adsorption. The second part involved testing the prepared adsorbent monoliths and foammonoliths with single (such as CO2, CH4 and H2S) and mixed (such as CO2/CH4 and CO2/CH4/H2O vapour) gases under different operating conditions to assess their dynamic adsorption performances for biogas upgrading. 13X zeolite and MIL-101(Cr) monoliths and K2CO3/13X zeolite foam-monoliths were used as model adsorbent structures in single and mixed gas adsorption experiments. The study has shown that 13X zeolite monoliths and K2CO3/13X zeolite foam-monoliths have excellent adsorption performances for CO2, H2S and H2O vapour and they could upgrade the biogas to a high quality (i.e., up to about 98% vol. CH4). For purified MIL-101(Cr) monoliths, it was discovered that they have relatively good adsorption performance for CO2, H2S, CH4 and H2O vapour and they could upgrade the biogas to a moderate quality (i.e., up to about 67% vol. CH4). In both humid and dry conditions, K2CO3/13X zeolite foam-monoliths were found to have the highest selectivity of CO2 over CH4 compared to 13X zeolite and purified MIL-101(Cr) monoliths. The third part was related to the evaluation and comparison of kinetic adsorption and gas flow dynamic performances of the prepared adsorbent monoliths with those of packed beds of adsorbent beads. In these studies, LiLSX zeolite monoliths and beads were used as model adsorbent structures. The kinetic adsorption study has discovered that LiLSX zeolite monoliths have slightly higher overall mass transfer resistance than packed beds of LiLSX zeolite beads. It has been shown that the overall mass transfer resistance in monoliths could be reduced by decreasing the channel diameter and increasing the wall thickness. The gas flow dynamic study found that the mass transfer in monoliths was not contributed by the axial dispersion of gases and this was in contrast to the mass transfer in packed beds. LiLSX zeolite monoliths were found to have lower pressure drop compared to packed beds of LiLSX zeolite beads. This showed that the biogas upgrading process would be more energy efficient using adsorbent monolith/foammonolith systems compared to packed bed systems.

There are few empirical studies of food quality within hospital food service systems. Although it is widely accepted that food quality is a multi-faceted phenomenon, much attention has been paid to single component explanations in the past. The aim of this study throughout has been two fold - to develop a model suitable for evaluating the quality of food in conventional hospital food service systems; and to evaluate food quality in selected hospitals in the Trent Regional Health Authority and West Midland Regional Health Authority using the model. A key outcome in this study has been the development of a multifaceted measurement of food quality to help catering managers deploy resources effectively, in conventional hospital food service systems. This approach was achieved using a variety of qualitative and quantitative information to score six food quality components and 15 influencing variables. Food quality was defined as a multi-dimensional measure to include measures of satisfaction of patients and catering staff, productivity, safety, and nutritional adequacy. Measures of influencing variables were chosen or adapted from those available in food service operations insofar as was possible. Where none was available, methods were developed. The variables were grouped into two major categories: human resources and system resources. A survey of 12 hospital conventional food service systems in the UK was undertaken and detailed information was collected from each, including surveys of 933 patients and 327 catering staff. Patient satisfaction with the quality of hospital food and food-related service was evaluated by patient questionnaires. It was measured by assessing 14variables. Patients seem to be generally satisfied with the food served. In the regression analysis none of the influencing variables explained the component of 'patient satisfaction' at the level of P < 0.05, suggesting that it is a different kind of component from the other 4. Importantly the component 'patient satisfaction' appears to be explained predominantly by patients' own demographic and emotional variables rather than by objective catering system factors. Age and appetite were found to significantly correlate with patient satisfaction scores. The component of food waste was found to have a high negative correlation with patients' satisfaction. It may be possible to use food waste as an index of patient satisfaction in future research. Catering staff - satisfaction was evaluated by measuring employee job attitudes towards five aspects of their job using the Job Description Index (JDI). The JDI is directed toward specific areas of satisfaction rather than global or general satisfaction and was easily administered. The food service workers surveyed in this research were less satisfied with their jobs than are other types of workers in other industries. In the regression analysis total number of patients explains around 36% of the variation in staff satisfaction. The productivity level was based upon the total meal equivalents divided by the total labour hours required to produce and serve them. The regression analysis suggests that around 77% of the variance in productivity is explained by labour cost. The safety component was based upon two elements which were microbiological control and temperature control. The results of regression analysis suggest that the number of menu items and the subsidizing meal ratio explain around 74% of the variation in the safety component. Nutritional adequacy was evaluated indirectly by measurement of food waste. In the regression analysis more than 68% of food waste component can be explained by the variable occupancy rate. Correlations between the food quality components show that a non-significant relationship existed between all but one of the components of food quality studied. A significant negative correlation existed between the patients'satisfaction with the hospital meal and service and the food waste; this was expected. The non-significant correlations between the components of food quality showed the independence of components, confirming the need for a multi-dimensional model of food quality. The findings of this research support the notion that food quality is a multi-faceted phenomenon and have led to the development of a practical way of measuring it.

This study is about the information-seeking behavior that bilingual users – specifically, native Chinese speakers whose second language is English - exhibit when performing an online search. Bilingual online searching occurs when bilingual users submit queries to search for information in two languages. This study seeks to explore the information-seeking behavior of bilingual users in an attempt to discover possible ways of improving bilingual users’ online searching experience. The study focuses on defining the characteristics of bilingual users’ information-seeking behavior on the web. This research employed questionnaire and interview methods to determine (1) The information-seeking behavior of bilingual users; (2) Language’s influence on online searching; (3) Bilingual users’ opinions on the online searching support they need. The sample was recruited from Chinese native-speaking students in Pittsburgh. The researcher found that bilingual users tend to select the language that best fits their information needs rather than doing multilingual online searching and that they used search engines as multilingual tools. The researcher also identified five types of search strategies preferred for bilingual online searching. They include: directly linking, keyword searching, browsing, comparison, and externally linking. Directly linking means that the participant has a specific website in mind so he/she just go to the website directly or search for the website in the search engine. Browsing means that they retrieved a list of resources first and browse through them. Comparison means that they obtained several search results first and compare them. Externally linking strategy means that participants link from the website they accessed originally. This is a descriptive study of users completing four specific tasks and it only emphasizes on users’ opinions about the search support given by the bilingual online searching interface.