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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.
131

A study of structures and corrosion properties of boron implanted 440C and 316 stainless steels

Kim, Ku-Yong 05 1900 (has links)
No description available.
132

GROUP 13 CHELATES IN PHOSPHATE DEALKYLATION

Mitra, Amitabha 01 January 2006 (has links)
A series of mononuclear boron halides of the type LBX2 (LH = N-phenyl-3,5-di-tbutylsalicylaldimine,X = Cl (2), Br (3)) and LBX ( LH2 = N-(2-hydroxyphenyl)-3,5-di-tbutylsalicylaldimine,X = Cl (7), Br (8); LH2 = N-(2-hydroxyethyl)-3,5-di-tbutylsalicylaldimine,X = Cl (9), Br (10); LH2= N-(3-hydroxypropyl)-3,5-di-tbutylsalicylaldimine,X = Cl (11), Br (12)) were synthesized from their borate precursorsLB(OMe)2 (1) (LH = N-phenyl-3,5-di-t-butylsalicylaldimine ) and LB(OMe) (LH2 = N-(2-hydroxyphenyl)-3,5-di-t-butylsalicylaldimine (4), N-(2-hydroxyethyl)-3,5-di-tbutylsalicylaldimine(5), N-(3-hydroxypropyl)-3,5-di-t-butylsalicylaldimine (6)). Theborate precursors, 1, 4 - 6, in turn, were prepared by refluxing the corresponding ligandsLH or LH2 with excess B(OMe)3. The boron halide compounds were air- and moisturesensitiveand compound 7 on hydrolysis gave the oxo-bridged compound 13 thatcontained two seven-membered boron heterocycles. The boron halide compoundsdealkylated trimethyl phosphate in stoichiometric reactions to produce methyl halide andunidentified phosphate materials. Compounds 8 and 12 were found to be the mosteffective dealkylating agents. Compound 8 on reaction with t-butyl diphenyl phosphinateproduced a unique boron phosphinate compound LB(O)OPPh2 (14) containing a terminalphosphinate group. Compounds 1-14 were characterized by 1H, 13C, 11B, 31P NMR, IR,MS, EA and MP. Compounds 5, 6, 11, 12 and 13 were also characterized by singlecrystalX-ray diffraction.The alkane elimination reaction between Salen(tBu)H2 ligands and diethylaluminumbromide was used to prepare the four Salen aluminum bromide compounds,salen(tBu)AlBr (15) (salen = N,N'-ethylenebis(3,5-di-tert-butylsalicylideneimine)),salpen(tBu)AlBr (16) (salpen = N,N'-propylenebis(3,5-di-tert-butylsalicylideneimine)),salben(tBu)AlBr (17) (salben = N,N'-butylenebis(3,5-di-tert-butylsalicylideneimine)) andsalophen(tBu)AlBr (18) (salophen = N,N'-o-phenylenenebis(3,5-di-tertbutylsalicylideneimine)).The compounds contained five-coordinate aluminum either in adistorted square planar or a trigonal bipyramidal environment. The bromide group inthese compounds could be displaced by triphenylphosphine oxide or triphenyl phosphateto produce the six-coordinate cationic aluminum compounds [salen(tBu)Al(Ph3PO)2]Br(19), [salpen(tBu)Al(Ph3PO)2]Br (20), [salophen(tBu)Al(Ph3PO)2]Br (21) and[salophen(tBu)Al{(PhO)3PO}2]Br (22). All the compounds were characterized by 1H,13C, 27Al and 31P NMR, IR, mass spectrometry and melting point. Furthermore,compounds 15, 16, 17, 18, 20, 21 and 22 were structurally characterized by single-crystalX-ray diffraction. Compounds 15, 17 and 18 dealkylated a series of organophosphates instoichiometric reaction by breaking the ester C–O bond. Also, they promoted thedealkylation reaction between trimethyl phosphate and added boron tribromide.Stoichiometric reaction of compound 15 with trimethyl phosphate produced thealuminophosphinate compound salen(tBu)AlOP(O)Ph2 (23). Compound 16 on reactionwith tributyl phosphate produced the aluminophosphate compound[salpen(tBu)AlO]2[(BuO)2PO]2 (24). Compounds 23 and 24 were characterized by singlecrystalX-ray diffraction and spectroscopically.
133

Sustainable development and the global mining industry

Argust, Peter William January 2000 (has links)
No description available.
134

The machining of annealed and hardened steels using advanced ceramic cutting tools

Abrão, Alexandre Mendes January 1995 (has links)
No description available.
135

Effects of boron deficiency on RNA metabolism in Phaseolus aureus root tips

Chapman, Keith Samuel Roy January 1972 (has links)
vii, 122 leaves : ill. ; 25 cm / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1973) from the Dept. of Agricultural Biochemistry and Soil Science, University of Adelaide
136

Effects of boron deficiency on RNA metabolism in Phaseolus aureus root tips

Chapman, Keith Samuel Roy January 1972 (has links)
vii, 122 leaves : ill. ; 25 cm / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1973) from the Dept. of Agricultural Biochemistry and Soil Science, University of Adelaide
137

Boron cosmochemistry.

Zhai, Mingzhe. SHAW, D.M. Unknown Date (has links)
Thesis (Ph.D.)--McMaster University (Canada), 1994. / Source: Dissertation Abstracts International, Volume: 56-08, Section: B, page: 4197. Adviser: D. M. Shaw.
138

Application of boron isotope ratios for identifying nitrate contamination sources in the groundwater of Avra Valley, Arizona.

Leenhouts, James M. January 1994 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1994. / Includes bibliographical references (leaves 133-135).
139

Synthesis of conjugates of L-fucose and ortho-carborane as potential agents for boron neutron capture therapy and Synthesis of 2,3-dideoxy-2,3-methanoribofuranoside glycosyl donors and a study of their use in stereocontrolled glycosylation reactions

Basak, Prakriti. January 2003 (has links)
Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xiii, 279 p.: ill. (some col.). Includes abstract and vita. Advisor: Todd L. Lowary, Dept. of Chemistry. Includes bibliographical references (p. 150-154).
140

Study of the boron nitrogen interaction and its influence on the catalysis of amide formation reactions by aromatic boronic acids

Li San Cheung, Ken Jason, January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Chemistry. Title from title page of PDF (viewed 2009/06/29). Includes bibliographical references.

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