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Deuterated variations of poIy(lauryl methacrylate) (PLMA) have been synthesised, this involved the initial synthesis of the monomer (LMA). This was achieved by a transesterification reaction between methyl methacrylate and lauryl alcohol using either hydrogenous or deuterated materials depending on which part of the resulting LMA monomer was to be deuterated. The physical properties of PLMA and LMA spread monolayers have been investigated using surface pressure - area isotherms and surface quasi - elastic light scattering (SQELS). The isotherms for PLMA show that the thermodynamic state of the polymer is poorer than theta conditions and no variation occurs with changes in temperature. LMA shows a drastic change in the nature of the isotherm as the temperature is varied. This has been attributed to the formation of lenses and the variation caused by temperature is due to a change in the rate of migration of the LMA molecules. The SQELS results show that the PLMA monolayer displays the characteristics of a Voigt solid model and shows no viscous relaxation processes. SQELS has also been used to demonstrate the biphasic nature of the monolayer at low surface concentrations, the size of the polymer 'islands' has been estimated to be in the range of 5 to 20mm. SQELS from LMA monolayers showed that the two higher surface concentrations gradually converted into the same state as that obtained for the low

We consider the effect of free -streaming axion emission on numerical models for the cooling of the newly born neutron star associated with SN1987A. We find that for an axion mass of greater than -10-3 eV, axion emission shortens the duration of the expected neutrino burst so significantly that it would be inconsistent with the neutrino observations made by the Kamiokande II (KII) and Irvine -Michigan- Brookhaven (IMB) detectors. However, we have not investigated the possibility that axion trapping (which should occur for masses 20.02 eV) sufficiently reduces axion emission so that axion masses greater than -2 eV would be consistent with the neutrino observations.

Master of Science / Department of Mechanical and Nuclear Engineering / Douglas S. McGregor / Fission chambers are a common type of detector used to determine the neutron flux and power of a nuclear reactor. Due to the limited space and high neutron flux in a reactor core, it is difficult to perform real-time flux measurements with present-day in-core instrumentation. Micro-pocket fission detectors, or MPFDs, are relatively small in size and have low neutron sensitivity while retaining a large neutron to gamma ray discrimination ratio, thereby, allowing them to be used as active neutron flux monitors inside a nuclear reactor core. The micro-pocket fission chamber allows for multiple detectors to be inserted into a flux port or other available openings within the nuclear reactor core. Any material used to construct the MPFD must be rugged and capable of sustaining radiation damage for long periods of time. Each calibrated MPFD provides measurements of the flux for a discrete location. The size of these detectors allows for a spatial map of the flux to be developed, enabling real-time analysis of core burnup, power peaking, and rod shadowing. Small diameter thermocouples can be included with the array to also measure the temperature at each location. The following document details the research and development of MPFDs for long term use in nuclear power reactors. Previous MPFD designs were improved, miniaturized, and optimized for long term operations in reactor test ports designed for passive measurements of fluence using iron wires. Detector chambers with dimensions of 0.08 in x 0.06 in x 0.04 in were attached to a common cathode and individual anodes to construct an array of the MPFDs. Each array was tested at the Kansas State University TRIGA Mark II nuclear reactor to demonstrate functionality. The linear response in reactor power was measured. These arrays have also demonstrated reactor power tracking by following reactivity changes in steady state operations and reactor pulsing events. Stability testing showed consistent operation at 100 kW for several hours. The MPFDs have been demonstrated to be a viable technology for in-core measurements.

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