This work is a compilation of ideas intended as a framework for an alternative approach to engaging ‘site’ in the design process, an approach that maintains and explores the complexities and subtleties of a landscape, of a place. Through two parallel explorations - one that considers an expanded and inclusive interpretation of landscape as the frame through which we engage with, and design, our surroundings, and one that examines the specific nature of this engagement as exchange between the self and the milieu - such an approach has been developed. This approach is called RECONNAISSANCE. Through encouragement of explicit, conscious consideration of how we perceive and experience a landscape, how this contributes to an understanding of a particular place and how this relates to and informs the practice of landscape architecture (both the process and the outcome), RECONNAISSANCE contributes to a strengthening of our abilities and actions as landscape architects.

This study used LA-ICP-MS on a documented sample of modern teeth to sample from a continuous line across the cementum increments thus creating a temporal line graph of the elemental composition against distance. The knowledge of cementum was extended through (1) a more complete elemental composition analysis and (2) the relation of element distribution to the ultrastructure structure throughout the life of a tooth. This study was exploratory and demonstrated that lead, zinc, mercury, and barium follow the same general line of changes, and most likely represent changes in health and exposure to these metals in the general environment. Copper, manganese and vanadium varied very little. Technological limitations prevented the examination of element levels in any one annulation.

Remediation of trace element-contaminated sites must consider both the nature of the contaminants and environmental surroundings. This thesis examined treatments for two contamination scenarios. The first study characterized chromium dynamics during the redox-sorption treatment of aqueous hexavalent chromium with the reducing agent sodium dithionite and two iron oxides. Results showed that chromium was successfully removed from solution by precipitation and sorption. The iron oxide derived from ferric chloride had a greater sorption capacity for hexavalent chromium than the oxide derived from ferrous chloride. The second study examined the phytoextraction treatment of soils contaminated with multiple trace elements. Deschampsia caespitosa plants had better early growth in the contaminated high-organic matter soil than three Brassica species. However, D. caespitosa plants did not take up sufficient amounts of trace elements during the study to be considered useful for short-term phytoextraction. These findings are applicable to the development of effective trace element remediation methods.

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No description available.

The aim of this thesis was to improve the properties of pressed and sintered aluminium powder alloys. This improvement was to be achieved using two methods. The first method involved the selection of an alloy system using binary aluminium phase diagrams and a knowledge of the phase diagram characteristics of ideal sintering systems. The second approach involved the judicious use of selected trace element additions to modify the sintering characteristics of aluminium and its alloys. A trace amount of magnesium was found to be critical to the sintering of aluminium powder due to its disrupting effect on the tenacious oxide layer covering the powder particles. The critical amount of Mg required to optimise both density and mechanical properties is dependent on the specific volume of oxide and the therefore particle size. The optimum concentration is 0.1-1.0wt% Mg. The Al-Sn phase diagram exhibits many of the characteristics of an ideal sintering system. Unsurprisingly, Sn was found to be an extremely efficient sintering aid, but only in the presence of Mg. Near full density parts were produced using an Al-8Sn-0.15Mg alloy in short sintering times (30 minutes). Additionally, as-sintered ductilities exceeding 20% were achieved using an Al-2Sn-0.15Mg alloy. Alloys based on the Al-Sn-Mg system lend themselves to sintering without compaction and therefore freeformed Al-Sn-Mg alloys have been produced and sintered to near full density from a starting density of ~50%. Trace amounts of Sn (Pb, In, Bi, or Sb) enhance the sintering response of an Al-4Cu-0.15Mg alloy via a vacancy binding mechanism. A similar mechanism suppresses natural ageing and stimulates artificial ageing when trace amounts of Sn are added to this alloy. A Sn-modified 2XXX series alloy has also been produced with mechanical properties nearly 20% above current commercial alloys. Along with the addition of 0.1wt%Sn, this improvement required an alteration to the solution treatment cycle which allowed the use of a higher sintering temperature without the formation of large amounts of boundary phase.

The aim of this thesis was to improve the properties of pressed and sintered aluminium powder alloys. This improvement was to be achieved using two methods. The first method involved the selection of an alloy system using binary aluminium phase diagrams and a knowledge of the phase diagram characteristics of ideal sintering systems. The second approach involved the judicious use of selected trace element additions to modify the sintering characteristics of aluminium and its alloys. A trace amount of magnesium was found to be critical to the sintering of aluminium powder due to its disrupting effect on the tenacious oxide layer covering the powder particles. The critical amount of Mg required to optimise both density and mechanical properties is dependent on the specific volume of oxide and the therefore particle size. The optimum concentration is 0.1-1.0wt% Mg. The Al-Sn phase diagram exhibits many of the characteristics of an ideal sintering system. Unsurprisingly, Sn was found to be an extremely efficient sintering aid, but only in the presence of Mg. Near full density parts were produced using an Al-8Sn-0.15Mg alloy in short sintering times (30 minutes). Additionally, as-sintered ductilities exceeding 20% were achieved using an Al-2Sn-0.15Mg alloy. Alloys based on the Al-Sn-Mg system lend themselves to sintering without compaction and therefore freeformed Al-Sn-Mg alloys have been produced and sintered to near full density from a starting density of ~50%. Trace amounts of Sn (Pb, In, Bi, or Sb) enhance the sintering response of an Al-4Cu-0.15Mg alloy via a vacancy binding mechanism. A similar mechanism suppresses natural ageing and stimulates artificial ageing when trace amounts of Sn are added to this alloy. A Sn-modified 2XXX series alloy has also been produced with mechanical properties nearly 20% above current commercial alloys. Along with the addition of 0.1wt%Sn, this improvement required an alteration to the solution treatment cycle which allowed the use of a higher sintering temperature without the formation of large amounts of boundary phase.

Thesis (Ph. D.)--Ohio State University, 2007. / Originally issued in print. "Publications [by Jih-Pai Lin]": p. ix-x. Includes bibliographical references (p. 342-392). Full text release at OhioLINK's ETD Center delayed at author's request

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

Diss. (sammanfattning). Umeå : Sveriges lantbruksuniv. / Härtill 5 uppsatser.