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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.
361

Rhizosphere microbial diversity in PAH's contaminated and uncontaminated soil

Randima, Livhuwani Priscilla. January 2009 (has links)
Thesis (M.Sc.)(Microbiology))--University of Pretoria, 2009. / Summary in English. Includes bibliographical references.
362

Biodegradation of aromatic hydrocarbons : microbial and isotopic studies /

Diegor, Elizabeth Justa M., January 2000 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2000. / Bibliography: leaves 105-119.
363

Solid peroxide stimulated phenanthrene removal from contaminated river sediment

Schaffnit, Katherine Stuart. January 2009 (has links) (PDF)
Thesis (M.S. in environmental engineering)--Washington State University, December 2009. / Title from PDF title page (viewed on Jan. 14, 2010). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 41-42).
364

Preparation of benzoenyne-allenes, enyne-isocyanates and enyne-carbodiimides and their applications in the synthesis of polycyclic aromatic hydrocarbons and heterocycles

Li, Hongbin, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xvi, 377 p. : ill. Includes abstract. Includes bibliographical references (p. 120-128).
365

Thermal activation and intermediates of six-membered cyclic hydrocarbons and alkyl nitrites on Pt(111) and Cu(100) /

Ihm, Hyeran, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 158-168). Available also in a digital version from Dissertation Abstracts.
366

Polycyclic aromatic hydrocarbon degradaton by novel bacteria isolated from burrow sediments of marine benthic macrofauna /

Chung, Wai Ki, King, Gary Boettcher, Katherine. Distel, Daniel L. MacRae, Jean D. Singer, John. January 2001 (has links)
Thesis (Ph. D.) in Microbiology--University of Maine, 2001. / Includes vita. Advisory Committee: Gary King, Clare S. Darling Prof. of Oceanography and Prof. of Microbiology and Marine Studies, Advisor; Katherine Boettcher, Asst. Prof. of Microbiology; Daniel Distel, Assoc. Prof. of Biochemistry, Microbiology & Molecular Biology; Jean MacRae, Asst. Prof. of Civil & Environmental Engineering; John Singer, Prof. of Microbiology and Chair of Dept. of Biochemistry, Microbiology & Molecular Biology. Includes bibliographical references (leaves 77-91).
367

Genetic, metabolic, and histopathological studies of particle-associated respiratory alterations

Ghanem, Mohamed Mohamedy. January 2003 (has links)
Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xiv, 235 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 201-235).
368

Biodegradation of polycyclic aromatic hydrocarbons in marine sediment under anoxic conditions

Lü, Xiaoying, 吕晓莹 January 2011 (has links)
published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy
369

Non-heme iron(III) complexes catalyzed oxidation of saturated hydrocarbons and cis-dihydroxylation of alkenes

Chow, Wai-shan., 周慧珊. January 2010 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
370

Ruthenium porphyrin catalyzed nitrene insertion into C-H bonds of aromatic heterocycles, aldehydes and alkanes

Xiao, Wenbo., 萧文博. January 2012 (has links)
Transition metal catalyzed selective nitrene insertion into C-H bonds, which allows direct incorporation of nitrogen functionality into hydrocarbons, represents an appealing methodology for C-N bond formation, a type of bond formation of great importance in organic synthesis due to the prevalence of amino groups in biologically active natural products and pharmaceuticals. Organic azides are atom-economic and an environment-benign nitrene source. This dissertation reports the use of organic azides as a nitrene source to develop a series of protocols for C-H bond functionalization by metal-catalyzed nitrene insertion, including the diimination of indoles, the phosphoramidation of aldehydes and the amination of hydrocarbons catalyzed by ruthenium porphyrins. Carbonylruthenium(II) porphyrin complex Ru(TTP)(CO) (TTP = meso-tetrakis(p-tolyl)porphyrinato dianion) is an effective catalyst for nitrene transfer to sp2 C-H bonds of indoles using aryl azides (ArN3) as a nitrene source. This “Ru(TTP)(CO) + ArN3” protocol selectively results in the diimination of indoles without the corresponding monoimination products being detected. In the presence of a catalyst Ru(TTP)(CO), the reactions of N-methylindole with ArN3 (Ar = 4-nitrophenyl; 3,5-bis(trifluoromethyl)phenyl), and reactions of a variety of N-substituted indoles with 4-nitrophenylazide, afford 2,3-diiminoindoles in good to excellent yields (up to 90%). This unique type of 2,3-diimination products was characterized by NMR spectroscopy, mass spectrometry and single crystal X-ray crystallography. The catalytic diimination product from N-methylindole and ArN3 (Ar = 3,5-bis(trifluoromethyl)phenyl) can also be obtained through stoichiometric reaction of N-methylindole with the corresponding bis(arylimido)ruthenium(VI) porphyrin, suggesting the possible involvement of RuVI(TTP)(NAr)2 intermediates in the Ru(TTP)(CO)-catalyzed diimination reactions. Dichlororuthenium(IV) porphyrin complex Ru(TTP)Cl2 efficiently catalyzes the phosphoramidation of aldehydes with phosphoryl azides (RO)2P(O)N3 via a nitrene insertion into sp2 C-H bonds of aldehydes. This represents the first study on the catalytic activity of a ruthenium(IV) porphyrin towards nitrene insertion into C-H bonds. The “Ru(TTP)Cl2 + (RO)2P(O)N3” protocol exhibits high chemoselectivity and functional group tolerability. Good to excellent product yields (up to 99%) have been obtained for the Ru(TTP)Cl2-catalyzed phosphoramidation of a wide variety of aldehydes with commercially available (PhO)2P(O)N3 (DPPA) and phosphoramidation of p-tolualdehyde with various (RO)2P(O)N3 (R = Me, Et, CCl3CH2, 4-nitrophenyl). The reaction can be scaled up by adding phosphoryl azide dropwise. The use of commercially available DPPA in this protocol offers a convenient and practical method for the synthesis of N-acylphosphoramidates. “Ru(TDCPP)Cl2 + (CCl3CH2O)2P(O)N3” (TDCPP = meso-tetrakis(2,6-dichlorophenyl)porphyrinato dianion) serves as an effective protocol for intermolecular nitrene insertion into sp3 C-H bonds of hydrocarbons. Using this protocol, a variety of hydrocarbons including cycloalkanes (such as cyclohexane) and ethylbenzenes undergo sp3 C-H amination in moderate to high yields (up to 86%). Compared with ruthenium(II) porphyrins such as Ru(TDCPP)(CO) and dirhodium carboxylates such as Rh2(OAc)4, Ru(TDCPP)Cl2 displays a markedly higher catalytic activity towards the nitrene sp3 C-H insertion with (CCl3CH2O)2P(O)N3. In addition, intramolecular nitrene insertion into sp3 C-H bond can also take place in good yields with Ru(TDCPP)Cl2 as the catalyst. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

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