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A disruption is the sudden and uncontrolled loss of plasma confinement in a tokamak. Disruptions on the Mega Amp Spherical Tokamak (MAST) are characterised in terms of thermal quench timescales, energy balance and pre disruption energy loss. Analysis of the energy balance during disruptions on MAST has shown that approximately 10% of the stored energy is radiated during a disruption and 80% is deposited onto the divertor. The energy loss prior to the thermal quench is found to be 50% of the maximum energy in the plasma, which is half the value assumed for the ITER design. Disruptions occur when operational boundaries, in terms of current, pressure and density, are exceeded. An analysis of the operational boundaries in MAST shows that the frequency of disruptive events increases as the density is raised to 1.5 times the Greenwald density limit and that the pressure limit is consistent with empirical scalings. The current limit on MAST is triggered before the expected value of q95 is reached. Further analysis of the disrupting discharges in MAST shows that there is substantial energy loss prior to the thermal quench of up to 50%, however, disruptions at full performance are frequent. Disruption mitigation on MAST, via massive gas injection, has been performed using 0.32 bar litres (7.7x1021 particles, 10 times the plasma inventory) of a 90% helium and 10% argon mixture. The evolution of the plasma during mitigation is followed using high speed (up to 50kHz) imaging and high temporal (0.2ms) resolution Thomson scattering. High speed imaging of the plasma shows that the neutral impurities are confined to the plasma periphery. Impurity ions penetrate to the q=2 surface and mix with the bulk plasma during the thermal quench. Thomson scattering data shows significant (double the initial core density) build of density on rational surfaces, specifically q=2, prior to the thermal quench. Analysis of the power load to the divertor during mitigated disruptions shows reductions of 60% in peak power loadings compared to unmitigated. The energy balance during mitigated disruptions shows an increase in the radiated energy to 40% of the total stored energy and a decrease in the energy to the divertor of 40%. The effect of mitigation is to increase the current quench time and decrease the magnitude of halo currents by 80%

Traditional methods of ammonium removal from municipal wastewaters rely on naturally occurring biological processes, where ammonium is converted into less harmful substances before being released into the environment. These processes are extremely effective at nitrogen removal but are less responsive to shock loads, in which case they can fall short of achieving the required effluent quality. In recent years research has been conducted into the possibility of using ion exchange technology as a complementary process for the. removal of ammonium from wastewater streams. Much of the research has been concerned with the performance of naturally occuring materials, zeolites, with much of the work being undertaken at laboratory scale using synthetic solutions. This study investigates the performance of the modified media, MesoLite, using real and synthetic solutions, at both laboratory and pilot scale, in the presence of competing cautions. Initial studies were performed under batch conditions to assess the effect of a number of parameters such as contact time, solution ammonium concentration and pH on the uptake of ammonium on to MesoLite. This was followed by a investigation into a number of design parameters under dynamic conditions, leading to a pilot scale examination of the potential of the process to be used for the application of removing ammonium from low concentration wastewater treatment works effluents. Subsequent experiments were performed pilot scale to investigate the benefit of using the ion exchange process for ammonium removal from high strength liquors arising from the sludge dewatering process. Results indicate that a range of parameters affects the performance of the media and optimum performance is observed at high ammonium concentrations with increased contact time at pH 6-7. Results also show that MesoLite was successful in removing ammonium from high concentration sludge liquors, giving a total capacity of 47-51 g + -1 + -1 NH4 N kg and a operational capacity of 27 36 g NH4 N kg . The treatment of low concentration effluents return a total capacity of 19 g NI-14+-N kg`1 and a operational capacity of 9.5 g NI-14+-N kg`1. However, this reduced capacity is offset by the significant increase run time, from 1.5 to 22 days, and a increase in the amount of liquid treated from 140 bed volumes to in excess of 6000 bed volumes.

This research interrogates South Korean women’s gender, ethnic and national identity construction revealed through sport spectacle. Two phases of the interviews were conducted for the research: focus group interviews during the 2004 Athens Olympics and individual interviews between March and April 2005, the period of the final qualifying stage for the 2006 FIFA World Cup. Newspaper extracts on the Olympics and the football matches were presented in the interviews. The analysis of the women’s identity construction was contextualized in relation to South Korea’s socio-cultural, historical and political networks. Globalisation provides the overall framework for the research. Globalisation has dramatically transformed the way people construct their relations to themselves, others and their nation. The research explored how the interviewed women produced and reproduced the meanings and values of the sport events and sport games in search for a sense of security and certainty in the ever-shifting global context. Their struggles to ‘live’ in the new social milieu, a process of reterritorialisation, were also analysed. Moreover, the women’s relationships with North Korea were examined based on the concepts of the ethnic identity and also of the nation as a historical community with shared culture, tradition and history. Although infamously labeled internationally as part of the ‘axis of evil’, North Korea provided a source of ambiguous identity to the interviewees. The women’s perceptions of Japan, South Korea’s old enemy, were also investigated around the themes of postcolonial identities. In addition, the research demonstrated the women’s gendered perceptions of sportswomen and sportsmen and an idea of nationhood represented by them.