Chow, Wing Hei = 白鑄鐵特殊的微結構--網絡圖案 / 周穎熙. / Thesis submitted in: November 2007. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Chow, Wing Hei = Bai zhu tie te shu de wei jie gou -- wang luo tu an / Zhou Yingxi. / Abstract --- p.i / Acknowledgements --- p.iii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Background of Thermodynamic --- p.3 / Chapter 1.3 --- Nucleation in pure metals --- p.4 / Chapter 1.4 --- Introduction of Growth --- p.7 / Chapter 1.5 --- Solidification of the Single Phase Binary Alloy --- p.9 / Chapter 1.6 --- Solidification of the Binary Eutectic Alloy --- p.12 / Chapter 1.7 --- Phase Separation by Nucleation and Growth --- p.15 / Chapter 1.8 --- How to obtain large undercooling --- p.19 / References --- p.20 / Figures --- p.22 / Chapter Chapter 2 --- Experiment / Chapter 2.1 --- Experimental Preparation --- p.31 / Chapter 2.2 --- Experimental Procedures --- p.32 / Chapter 2.3 --- Sample Analysis --- p.33 / References --- p.36 / Figures --- p.37 / Chapter Chapter 3 --- Network patterns in a white cast iron / Result --- p.38 / Reference --- p.58 / Figures --- p.64

High nutrient, low chlorophyll (HNLC) regions, where the availability of iron (Fe) limits primary production, comprise approximately 40% of the global ocean. Variability in Fe supply to these regions has the potential to impact Earth's climate by affecting the efficiency of the biological carbon pump, and thereby carbon dioxide uptake by the oceans. Characterizing Fe sources to HNLC regions is thus crucial for a better understanding of the connections and feedbacks between the ocean and climate change. This work addresses the question of Fe supply to two HNLC regions: the Southern Ocean and the subarctic northeast (NE) Pacific Ocean. In both regions, dissolved Fe (dFe) and the reduced form of iron, Fe(II), were measured in the water column. In the Southern Ocean, measurements were undertaken under the seasonal pack ice in the East Antarctic south of Australia. The results indicate that the sea ice represents a significant dFe source for the under-ice water column in spring, and that the Fe delivered from brine drainage and sea ice-melt likely contributes to the formation of the spring bloom at the ice edge. Shelf sediments were also found to supply dFe to the water column. Their effect was most pronounced near the shelf break and at depth, but offshore transport of Fe-enriched waters was also implicated. Fe(II) concentrations in spring were very low, most likely due to a lack of electron donors in the water column and limited solar radiation underneath the sea ice. Repeat measurements along a transect in the subarctic NE Pacific indicate that shelf sediments supply dFe and Fe(II) at depth, but their influence does not appear to extend offshore beyond several hundred kilometres. Episodic events such as the passage of sub-mesoscale eddies may transport subsurface waters a limited distance from the shelf break, supplying Fe(II) in a depth range where upwelling and deep mixing could bring it to the surface. Offshore, dFe shows little variability except in June 2012, where an aerosol deposition event is suspected to have increased dFe concentrations at depth. Fe(II) concentrations offshore are generally low, but show transient maxima at depth that likely result from remineralization processes in the oxygen deficient zone that stretches from ~600 to 1400 m depth in the subarctic NE Pacific. Elevated Fe(II) concentrations at depth were also observed in conjunction with the aerosol deposition event, which might indicate Fe(II) production associated with settling particles. However, the aerosol deposition event, which most likely stemmed from forest fires in Siberia, did not appear to trigger a phytoplankton bloom in surface waters, possibly due to a lack of Fe fertilization from the deposited material, or due to toxic effects on the resident phytoplankton community. Dust deposition from the atmosphere is considered a major Fe supply mechanism to remote HNLC regions, but the factors affecting Fe solubility of dust are poorly constrained. A laboratory experiment was conducted to test whether the presence of superoxide, a reactive oxygen species, enhances the dissolution of dust from different geographic source regions. The results indicate that superoxide may promote Fe solubilization from the dust sources tested, and that the effect of exposure to superoxide is on par with the Fe solubilizing effect of photochemical reactions. Given the possibility of widespread superoxide production by heterotrophic bacteria at all depths of the ocean, this finding suggests that significant Fe dissolution of dust particles could occur throughout the water column, not only in the well-lit surface layer. / Graduate / 0425 / 0996 / cschalle@uvic.ca

Thesis (Ph.D.) -- McMaster University, 1997. / Includes bibliographical references. Also available via World Wide Web.

Thesis (M.S.)--California Polytechnic State University, 2008. / Mode of access: Internet. Title from PDF title page; viewed on April 20, 2009. Major professor: Susan Hawk, Ph.D., R.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 Agriculture, with Specialization in Food Science and Nutrition." "August 2008." Includes bibliographical references (p. 72-78). Also available on microfiche.

Thesis (Ph. D.)--Johns Hopkins University, 1909. / Life. Reprinted from Maryland geological survey [report] vo. IX, 1910.

Thesis (Ph. D.)--Johns Hopkins University, 1909. / Life. Reprinted from Maryland geological survey [report] vo. IX, 1910.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1935. / Thesis title page added with title: Correlation of the Tyler and Copps formations of the Gogebic iron district, Michigan and Wisconsin. Typescript. Abstract: 1 leaf, at end. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 65-66.

Thesis (Ph. D.)--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 167-175).

Uppsala universitet, 1780, Thesis (doctoral). / Goldsmiths'-Kress no. 11983.1-1. - OCLC, 24295930. - Reproduction of original from Kress Library of Business and Economics, Harvard University.