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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

The Late Quaternary Climate and Environmental Changes of the Southwest China¡GStalagmite Carbon and Oxygen Isotope Records From Libo, Guizhou

Chung, Wei-Lin 28 August 2009 (has links)
Three stalagmites, JSD 01, JSD 02, and L12, were collected from Libo county in the southern Guizhou provence. JSD 01 and JSD 02 are 14cm long stalagmites from Golden Lion Cave and L12 is a 7.1cm long stalagmite from Dragon Spring Cave. Subsamples were drilled along the central axis for JSD 01V while subsamples of JSD 01H were obtained along the horizontal axis. Subsamples were analyzed for carbon and oxygen stable isotopes. The age determination for stalagmites were done by U-Th dating. The JSD 01 dates range from 93,700 to 95,200 yr B.P.; the JSD 02 dates are from 87,900 to 88,200 yr B.P.. The L12 dates are from 750 to 9,560 yr B.P.. The stalagmite record from Golden Lion Cave is correspondent to the marine isotope stage 5 (MIS 5) in age. The £_18O values of stalagmite JSD 01 record in MIS 5c are ranging from -6.58‰ to -5.17‰ ; £_13C values are from -9.19‰ to -6.84‰. Stalagmite JSD 01H records are ranging from -8.11‰ to -5.7‰ for £_18O and from -9.67‰ to -2.46‰ for £_13C. The £_18O values for stalagmite JSD 02 record in MIS 5c are from -8.15‰ to -7.12 ‰ and are from -9.09‰ to -5.19‰ for £_13C. The results indicate a warm and wet climate prevailing during MIS 5c and MIS 5b in Guizhou. An intensification of summer mosoon would increase in precipitation and vegetation above the cave. Result from JSD record shows data obtained from the horizontal axis may be younger in age than vertical axis in terms of sampling direction. The stalagmite L12 contains two sections: (1) Dates range from 700 to 2,400 yr B.P. between top and 35mm: the £_18O values are ranging from -8.23‰ to -7.07‰ while £_13C values are ranging from -11.61‰ to -6.98 ‰; (2) The £_18O values are ranging from -10.52‰ to -7.54‰ and £_13C values are from -10.75‰ to -6.98‰ between 35mm and 71mm. Results suggest a warm and wet climate prevailing during 9,000-9,600, with lighter £_18O values reflecting a strong summer monsoon. A decline of summer monsoon occurred around 9,000 yr B.P. as shown by a sharp increase in the £_18O. This sudden climatic change might lead to a decrease in vegetation and soil loss above the cave, resulting in the cease growth of the stalagmite. Around 2,400 yr B.P. the growth of stalagmite was resumed. The lighter £_13C values and heavier £_18O values represent a cooler and drier climate in late Holocene. After ~1,000 yr BP, a deforestation event occurred in the area probably which was induced by human activity.
282

Enhanced desorption : a method for off-line bioregeneration of granular activated carbon loaded with high explosives /

Morley, Matthew Christopher, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 171-183). Available also in a digital version from Dissertation Abstracts.
283

Production and characterization of activated carbon from waste tyre char by steam activation /

Yeung, Kit Ying. January 2009 (has links)
Includes bibliographical references (p. 159-170).
284

The influence of diet on stable carbon isotope composition in otoliths of juvenile red drum (sciaenops ocellatus)

Hanson, Chad W. Chanton, Jeffrey P. January 2004 (has links)
Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. Jeffrey P. Chanton, Florida State University, College of Arts and Sciences, Department of Oceanography. Title and description from dissertation home page (viewed June 16, 2004). Includes bibliographical references.
285

Tribological properties of hydrogenated and hydrogen-free diamond-like carbon coatings /

Ronkainen, Helena. January 2001 (has links) (PDF)
Thesis (doctoral)--Helsinki University of Technology, 2001. / Includes bibliographical references. Also available on the World Wide Web.
286

Development of a trans-rotational temperature diagnostic for vibrationally-excited carbon monoxide using single-photon laser-induced fluorescence

Leiweke, Robert John, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xviii, 265 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Walter R. Lempert, Dept. of Mechanical Engineering. Includes bibliographical references (p. 198-210).
287

The carbon budget of a shallow, tropical aquifer sources, sinks, and processes /

Richmond, Nicole L. January 2003 (has links)
Thesis (M.S.)--Miami University, Dept. of Geology, 2003. / Title from first page of PDF document. Document formatted into pages; contains vii, 127 p. : ill. Includes bibliographical references (p. 108-113).
288

Some thermodynamic properties of air and of carbon dioxide

Worthing, Archie G. January 1911 (has links)
Thesis (Ph. D.)--University of Michigan, 1911. / "Reprinted from the Physical review, vol. XXXIII, no. 4, October, 1911."
289

Size distributions of elemental carbon, organic carbon, and polycyclic aromatic hydrocarbons in ambient aerosols of the Pearl River Delta region /

Yu, Huan. January 2009 (has links)
Ph.D. in Atmospheric Environmental Science. Includes bibliographical references (p. 152-168).
290

Carbon chemistry the high temperature syntheses and applications of nanotubes and sp-hybridized compounds /

Mitchell, Daniel Robert, January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

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