Thesis (Ph.D.) --University of Adelaide, School of Chemistry and Physics, Discipline of Physics, 2006. / "5 April 2006" Bibliography: pages 147-150. Also available in print form.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Dec. 15, 2008). PDF text: vi, 93 p. ; 616 K. UMI publication number: AAT 3333017. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (M.Sc. (Mathematics)) - Rhodes University, 2008.

Thesis (M. Sc.(Computer Science))--University of Pretoria, 2003. / Abstract in English. Includes bibliographical references .

Thesis--Bonn. Extra t. p. with thesis statement inserted. / Bibliography: p. 45.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 103-112). Also available in electronic version.

The development of two original Monte Carlo models of solvent diffusion into a polymer is described. Employing a coarse grained model of a polymer solution on a regular lattice, the dynamic properties of both the solvent and polymer molecules can be observed. The "Simple" Monte Carlo model reliably reproduces Case I dynamics, but no departure from this is seen for any reasonable model parameters. This "Simple" Monte Carlo model is unable to reproduce Case II diffusion dynamics. One reason for this is that in this Monte Carlo model the processes of solvent diffusion and polymer relaxation are entirely independent processes. In this thesis it is suggested that a simple Monte Carlo model of this type will always produce Case I diffusion dynamics. The dynamic algorithm described in this work relies on simple instantaneous molecular motions between neighbouring lattice sites. It is shown that a diffusion process based on these motions is purely concentration dependent, relying only on the current state of the system. To use the Monte Carlo method to simulate Case II diffusion dynamics, the diffusion process is made time dependent by incorporating a history dependent model of diffusion first proposed by Crank (CRANK 1953). In this "History Dependent" Monte Carlo model the motions of both the solvent and the polymer are no longer instantaneous, but occur at a rate that approaches equilibrium by a first order process governed by a relaxation time characteristic of the viscoelastic relaxation of the polymer. This "History Dependent" Monte Carlo model successfully simulates most of the features of Case II diffusion and also demonstrates a return to Case I diffusion in the limit of long times. Unlike many models of Case II diffusion, this Monte Carlo model is able to simultaneously model the microscopic motions of both the solvent and the polymer molecules. This novel feature demonstrates the formation of a discontinuous moving boundary between the rubbery polymer and the glassy polymer that is typical of Case II diffusion dynamics.

The integrity of graphite components is critical for their fitness for purpose. Since graphite is a quasi-brittle material the dominant mechanism for loss of integrity is cracking, most specifically the interaction and coalescence of micro-cracks into a critically sized flaw. Including mechanistic understanding at the length scale of local features (meso-scale) can help capture the dependence on microstructure of graphites macro-scale integrity. Lattice models are a branch of discrete, local approach models consisting of nodes connected into a lattice through discrete elements, including springs and beams. Element properties allow the construction of a micro-mechanically based material constitutive law, which will generate the expected non-linear quasi-brittle response. This research focuses on the development of the Site-Bond lattice model, which is constructed from a regular tessellation of truncated octahedral cells. The aim of this research is to explore the Site-Bond model with a view to increasing understanding of deformation and fracture behaviour of nuclear graphite at the length scale of micro-structural features. The methodology (choice of element, appropriate meso length-scale, calibration of bond stiffness constants, microstructure mapping) and results, which include studies on fracture energy and damage evolution, are presented through a portfolio of published work.