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The aim of this study was to investigate the dynamic properties of potassium chloride, AN solutions and a commercial emulsion explosive and to understand their response in terms of shock theory and material properties. A plate impact facility was used to shock the KCl, subjecting it to a uni-axial strain state for the duration of the measurements. Stress and strain histories were recorded using piezo-resistive gauges. KCl is an ionic crystal which, when subject to shocks above 2.2 GPa, has a martensitic phase transformation. The stress histories were explained in terms of the shock and release waves. A novel technique was used to record the reverse phase transformation and to calculate the hysteresis. The assumption that a uni-axial strain state exists behind a phase transformation was verified, for the first time, experimentally. Two techniques were demonstrated that reduce and quantify the piezo-electric response of KCl. Conclusions from this investigation were analysed by two different types of computational simulation. Using a similar methodology to the KCl work a technique has been developed to determine experimentally the Hugoniot of liquids up to pressures of 10 GPa. The Hugoniots of a variety of AN solutions of different strengths and temperatures were recorded. The results were shown to agree with the predictions of two simple equations of state. The technique developed for AN solutions was applied to a commercial emulsion explosive (based on an AN solution) and the Hugoniot determined. The explosive was sensitised by adding quantities of glass micro-balloons and the pressures which induced the first stages of reaction for a given sensitisation were deduced.

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A novel approach has been adopted for in-situ growth of CNTs on CMOS Silicon on Insulator (SOI) devices. The growth and deposition of CNTs on SOI CMOS has been successfully implemented at high temperature (>700°C) using tungsten as an interconnect. A detailed study of the nanotubes growth dependence on a number of parameters has been carried out on fully processed SOI CMOS substrates. A novel growth process of depositing CNTs using the very low power CMOS microhotplate acting as the thermal source has also been carried out. One of the key advantages of this process is the confinement of high temperature to the heater region only during the CNT growth, thereby, keeping the electronic circuitry unaffected. The results of the growth were highly repeatable with no degradation of the CMOS devices. High quality multi walled CNTs were locally grown, self-aligned onto the pre-formed sensing metal interdigitated electrodes. A low temperature process (<450°C) for single walled and multi walled CNTs was also developed using a hot filament stage. This process is suitable for devices with aluminium interconnect and is CMOS compatible. The locally growth CNTs on the sensor devices were tested with NO₂ extensively and showed response at room temperature which was an improvement on the present gas sensing technologies. The sensor was found to offer reasonable sensitivity to 100 ppb of NO₂ and faster chemical response time at elevated temperatures (tens of seconds). The smart CNT micro-sensor also showed responses to ammonia, methanol and ethanol. The ultra-low power consumption of the hotplates on ultra-thin CMOS compatible membranes and the growth of CNTs on multi-chips at the same time, in parallel, show great potential for high volume manufacturability and is a potential way forward for the next generation nanostructured material sensors.

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