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A novel method of producing die compacted powder metallurgy components with fully en-closed internal structures was developed. The physical characteristics of the compacts were evaluated by measuring bulk density, internal density gradients and compressive green strength. Additionally, a finite element simulation was developed to evaluate the compaction process of the internal structure compact. The internal structure compact displayed the anticipated lower bulk densities due to the less dense internal structure than a conventional powder metallurgy compact, however; higher local densities were found within the internal structure compact at all compaction pressures. Compressive green strength characteristics showed unique results where the strength in-creased up to 300 MPa compaction pressure, however; at 400 MPa there was a distinct plat-eau in green strength. This phenomenon was attributed to an increase in differential shear stress around the internal structure with a minimal increase in density from 300 MPa to 400 MPa.

Trafficking of radioactive material, particularly special nuclear material (SNM), has long been a worldwide concern. To interdict this material the US government has installed radiation portal monitors (RPMs) around the globe. Building materials surrounding an RPM can greatly effect the detector’s background radiation levels due to Naturally Occurring Radioactive Material (NORM). In some cases this effect is so great that the initial RPM setup had to be rebuilt. This thesis develops a methodology for quick and efficient determination of the specific activity and composition of building materials surrounding a RPM to predict background levels, therefore determining the minimum detectable quantity (MDQ) of material. This methodology builds on previous work by Ryan et al by generating material and source cards for a detailed Monte Carlo N-Particle (MCNP) deck, based on an experimental RPM setup to predict the overall gamma background at a site. Gamma spectra were acquired from samples of building materials and analyzed to determine the specific activity of the samples. A code was developed to estimate the elemental composition of building materials using the gamma transmission of the samples. These results were compared to previous Neutron Activation Analysis (NAA) on the same samples. It was determined that densitometry provided an elemental approximation within 5% of that found through NAA. Using the specific activity and material composition, an MCNP deck was used to predict the gamma background levels in the detectors of a typical RPM. These results were compared against actual measurements at the RPM site, and shown to be within 10% of each other.

Includes articles co-authored by the author during the preparation of this thesis. / Includes erratum on back leaf. / Includes bibliographical references (leaves 257-299). / xvii, 300 [27] leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Examines regional variations in trabecular bone remodelling and bone loss following oophorectomy in the distal femur of the rat. The studies reveal a complex interaction between weight bearing and ovarian hormone deficiency, and show that physiological signals exist which can negate all adverse effects of postmenopausal osteoporosis / Thesis (Ph.D.)--Adelaide University, Dept. of Physiology, 2001

Thesis (Ph. D. - Geosciences)--University of Arizona, 1983. / Includes bibliographical references (leaves 168-177).

Thesis (M.S.)--University of North Carolina at Greensboro, 2007. / Title from PDF t.p. (viewed Feb. 29, 2008). Directed by Deborah Kipp; submitted to the School of Human Environmental Sciences. Embargoed until Dec. 20, 2008. Includes bibliographical references (p. 47-56).

Thesis (M.S.)--California Polytechnic State University, 2008. / Major professor: Scott Hazelwood, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Engineering with a specialization in Biomedical Engineering." "June 2008." Includes bibliographical references (leaves 46-49). Also available online. Also available on microfiche (2 sheets).

Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 150-166). Also available online.

Thesis (doctoral)--Karolinska Institutet, Stockholm, 1993. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--Karolinska Institutet, Stockholm, 1993. / Added t.p. with thesis statement inserted. Includes bibliographical references.