The aim of this thesis is to investigate the mathematics and modelling of the industrial crimper, perhaps one of the least well understood processes that occurs in the manufacture of artificial fibre. We begin by modelling the process by which the fibre is deformed as it is forced into the industrial crimper. This we investigate by presuming the fibre to behave as an ideal elastica confined in a two dimensional channel. We consider how the arrangement of the fibre changes as more fibre is introduced, and the forces that are required to confine it. Later, we apply the same methods to a fibre confined to a three dimensional channel. After the fibre has under gone a preliminary deformation, a second process known as secondary crimp can occur. This involves the `zig-zagged' material folding over. We model this process in two ways. First as a series of rigid rods joined by elastic hinges, and then as an elastic with a highly oscillatory natural configuration compressed by thrusts at each end. We observe that both models can be expressed in a very similar manner, and both predict that a buckle can occur from a nearly straight initial condition to an arched formation. We also compare the results to experiments performed on the crimped fibre. Throughout much of the process, the configuration of the fibre does not alter. This part of the process we call the block, and model the material in this region in two ways: as a series of springs; and as an isotropic elastic material. We discuss the coupling between the different regions and the process that occurs in the block, and consider both the steady state and stability of the system.

In 1995, the Environment Agency for England and Wales developed urban runoff treatment wetlands at two selected locations in Outer London. The systems have been monitored for a wide range of parameters including heavy metals, suspended solids and BOD over a period of two years. Seven storm events were also monitored. The ability of micro-organisms, isolated from the rhizosphere of wetland plants collected at both systems, to tolerate and accumulate heavy metals has also been investigated. This study has demonstrated that constructed wetland treatment systems are capable of reducing the pollutant loadings associated with urban runoff, and that such systems can be successfully established within urban areas. During dry weather, pollutant concentrations and loadings were typically low and associated removal efficiencies highly variable. However, during storm events, pollutant loadings increased and removal efficiencies improved, with mean removal efficiencies of 71% for Pb and 81% for Cr at the Dagenham wetland. An exception to this was for suspended solids which showed an overall increase of 99% during storm events. Several design and operational issues have been identified and addressed during the course of the monitoring programme, and recommendations for the improved design and operation of urban runoff treatment wetland systems have been made. A range of micro-organisms, isolated from both wetland systems, were able to tolerate elevated Zn and Pb concentrations. Two strains (Beauveria bassiana and Rhodotorula mucilaginosa) were selected for further work. Both strains could accumulate Zn and Pb, with B. bassiana showing a high capacity to bind Pb (maximum concentration of 136mgPb/g cells dry weight). Comparison of the growth of B. bassiana at 4°C and 30°C suggested that processes of microbial metal accumulation may occur throughout the year in treatment wetlands. The presence of Pb inside hyphae of B. bassiana, associated with hyphae walls and in the surrounding medium was confirmed. This study has found that micro-organisms isolated from urban runoff treatment wetlands can tolerate and accumulate Zn and Pb, and the application of these results to wetland treatment processes is discussed.

No description available.

Bibliography: leaves 178-186 / 186 leaves, [9] leaves of plates : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1989

126 leaves : ill., graphs, photos., tables ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1980

Thesis (Ph.D.)--McMaster University (Canada), 1991. / Source: Dissertation Abstracts International, Volume: 54-02, Section: B, page: 0917.

Thesis (Ph.D.)--McMaster University (Canada), 1996. / Source: Dissertation Abstracts International, Volume: 57-10, Section: B, page: 6328. Adviser: J. S. Preston.

Thesis (Ph. D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1989. / Includes bibliographical references (leaves 178-186).

Thesis (Ph.D.)--University of Wollongong,2004. / Typescript. Bibliography: leaf 205-214.

Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [197]-201).