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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.
701

Studies on nitrogen transformation and nitrate adsorption in soils / Nitrogen transformation and nitrate adsorption in soils

Singh, Budh Ram January 1968 (has links)
Typescript. / Bibliography: leaves [97]-105. / xiii, 105 l graphs, tables
702

Nitrogen fixation rates and controls at station ALOHA

Grabowski, Marcie N.W January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 48-54). / vii, 54 leaves, bound ill. 29 cm
703

Hydrazine in late transition metal-mediated N-C bond formation

Dabb, Serin Lloyd, Chemistry, Faculty of Science, UNSW January 2008 (has links)
This thesis describes investigations into the metal-mediated formation of nitrogen-carbon bonds from hydrazines and alkynes. Rh, Ir, Ru and Os metal complexes containing bidentate P,N- and N,N-donor ligands were all studied during the course of this work. A series of stereoisomers of metal complexes of general formula MCl2(PyP)2 (where M = Ru and Os, PyP = 1-(2-(diphenylphosphino)ethyl)pyrazole) (2.01-2.05) were synthesised. The isomerisation process of complexes 2.01-2.05 in solution was investigated. The ruthenium complex RuCl2(CO)(1-P-PyP)(2-P,N-PyP) (2.14), which contains one pendant PyP ligand bound through the P-donor ligand was synthesised, confirming the potential hemilability of the mixed P,N-donor ligand PyP. Chloride abstraction from the ruthenium complex trans,cis,cis-RuCl2(PyP)2 (2.01) was achieved using either a sodium or silver salt to yield the dimeric complexes of general formula [Ru(μ-Cl)(PyP)2]2[X]2 (where M = Ru, X = OSO2CF3 (2.06), BF4 (2.07), BPh4 (2.08), and BArF 2.09). [Os(μ-Cl)(PyP)2]2[BPh4]2 (2.10) was synthesised from sodium tetraphenylborate and trans,cis,cis-OsCl2(PyP)2 (2.04). The reactivity of dimeric complexes 2.06 and 2.08 towards substituted hydrazines was investigated. The methylhydrazine complex [Ru(PyP)2(NH2NHMe)][Cl][BPh4] (3.12) was synthesised. The methylhydrazine adduct of 3.12 binds to the metal centre in an end-on fashion via the NH2 group in solution, and in a bidentate fashion in the solid-state. This is the first reported example of a ruthenium complex containing a bidentate hydrazine ligand. The ruthenium-vinylidene complexes [RuCl(Me2PyP)2(=C=C(H)Ph)]BPh4 (4.15) and [RuCl(Me2PyP)2(=C=C(H)n-Bu)]BPh4 (4.16) (Me2PyP = 1-(2-(diphenylphosphino)ethyl)-3,5-dimethylpyrazole) were synthesised from trans,cis,cis-RuCl2(Me2PyP)2 (4.10) and the appropriate terminal alkyne. The reaction of alkynes with ruthenium complexes containing the PyP ligand was also investigated. Nitrogen-carbon bond formation was achieved through reaction of mono-substituted hydrazines with 4.06 and 4.07 to yield complexes of general formula [RuCl(1-P-Me2PyP)(2-P,N-Me2PyP)(2-N,C-(NH2N(R2)C(CH2R1)]BPh4 (where R1 = R2 = Ph (4.19), R1= Ph, R2 = Me (4.20), R1 = n-Bu, R2 = Ph, (4.21) or R1 = n-Bu, R2 = Me (4.22)). The mechanism of the formation of the stable metallocyclic complexes 4.19-4.22 was elucidated through studies of the reactivity of 4.15 towards a series of amines and hydrazines and relies on the labile nature of the N-donor of the P,N-donor ligand Me2PyP. A method for the synthesis of triflate complexes of rhodium Rh(PyP)(CO)(OSO2CF3) (5.13) and Rh(PyPhP)(CO)(OSO2CF3) (PyPhP = 1-(2-(diphenylphosphino)phenyl)pyrazole) (5.14) from rhodium chloride complexes was developed. The solid-state structure of rhodium triflate complex 5.14, which contained the more sterically rigid ligand PyPhP, exhibited a much greater distortion from the ideal square planar geometry than the rhodium analogue 5.13 which contains the PyP ligand. The triflate group of 5.13 and 5.14 was displaced by substituted hydrazines to yield new hydrazine complexes of rhodium. A series of Rh and Ir complexes with bidentate P,N- and N,N-donor ligands were found to catalyse the intermolecular hydroamination of alkynes with hydrazines. [Ir(bpm)(CO)2]BArF (6.08) was found to be the most efficient catalyst of those studies for this transformation, and was amongst the most efficient catalysts reported to date for this transformation. The influence of counter-ion was highly significant in the catalysed intermolecular hydroamination reaction. The substrate scope of the intermolecular hydroamination of alkynes with hydrazines was investigated using [Ir(bpm)(CO)2]BArF (6.08) as the catalyst.
704

Application of the acetylene reduction technique for quantifying dinitrogen fixation in Lupinus angustifolius L. / by Peter R. Gibson

Gibson, P. R. (Peter Ridley) January 1984 (has links)
Bibliography: leaves 170-191 / xv, 191 leaves, [26] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, Waite Research Institute, 1984
705

Studies on the nitrogen and water relations of wheat (Triticum aestivum L.) / by K.V.M. Parameswaran

Parameswaran, Kalathoor Velayduna Menon January 1975 (has links)
xv, 207 leaves : tables, graphs, photos ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1977) from the Dept. of Agronomy, University of Adelaide
706

Regulation of nitrate reductase activity in higher plants /

Aryan, Arun Prakash. January 1984 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1985. / Includes bibliographical references (leaves 142-164).
707

Heterocystous N₂-fixing cyanobacteria modeling of culture profiles, effect of red light, and cell flocculation study /

Pinzon-Gamez, Neissa M January 2006 (has links)
Thesis (M.S.)--University of Akron, Dept. of Chemical and Biomolecular Engineering, 2006. / "May, 2006." Title from electronic thesis title page (viewed 01/15/2008) Advisor, Lu-Kwang Ju; Committee members, Bi-min Zhang Newby, Donald Ott; Department Chair, Lu-Kwang Ju; Dean of the College, George K. Haritos; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
708

Putative dicarboxylate and amino acid transporters in soybean (Glycine max L.) : a molecular characterisation /

Christophersen, Helle Martha. January 2006 (has links)
Thesis (Ph.D.)--University of Western Australia, 2006.
709

Homogeneous sulfur tri-oxide formation in gas reburning for nitrogen oxides control

Jewmaidang, Jirasak. January 1999 (has links)
Thesis (M.S.)--Ohio University, Novmeber, 1999. / Title from PDF t.p.
710

Endogenous nitrogen recycling in the forage-fed ruminant

Atkinson, Rebecca L. January 2006 (has links)
Thesis (Ph. D.)--University of Wyoming, 2006. / Title from PDF title page (viewed on March 20, 2008). Includes bibliographical references (p. 122-132).

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