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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.
81

Antibiotic soil-drench treatments for the control of crown gall

Booth, John Austin, 1929- January 1958 (has links)
No description available.
82

Studies on the deoxyribonucleic acid of Agrobacterium tumefaciens (Smith and Town.) Conn.

Larsen, Philip Otto, 1940- January 1967 (has links)
No description available.
83

Two roads - no exit : an in camera discourse on negotiations in North America today

McIntyre, Donald G. 11 1900 (has links)
This work is an interdisciplinary exploration of negotiations between the nations that make up Canada. It explores the disparity that remains between Aboriginals and non Aboriginals in Canadian North America at a systemic level. It will show that the postcolonial era is rampant with colonial doctrine and that these principles and policies maintain a dogmatic system that can not allow for the continued existence of Aboriginals as separate and distinct peoples. I will show my understanding and interpretation of an old Indigenous system and suggest ways in which aspects of this ancient system may be valuable in creating a coordination of world views that can allow for both factions to exist and prosper. I will specifically address how the differing world views that exist between Aboriginal and non-Aboriginal Canadians—and the inequality between these two groups of peoples—has been and remains infused in the negotiation process that these governments attempt to complete. The final aspect of this work will be a theatrical production piece that allows (in some small way) the traditional Indigenous approach to ‘law’ to be given equal weight as the Supreme Court in Delgamuukw suggests.
84

Photo-active anthracene receptors for s-block and d-block metals

McSkimming, Gordon January 2001 (has links)
No description available.
85

Ecclesiastical revenue and resources in colonial La Paz : theory and practice of paying for secular churches

MacLean, R. A. January 2001 (has links)
No description available.
86

The synthesis and characterization by use of spectroscopic and x- ray methods of bromo, phosphine, and nitro derivatives of 13-phenyl- 1,4,7,10-tetraoxa-13-azacyclopentadecane

Sheu, Biing-Jahn January 1992 (has links)
The phenyl ring in the crown ether, 13-phenyl-1,4,7,10-tetraoxa-13-azacyclopentadecane (I), was used a site for functionalizing the compound. Electrophilic bromination of the ring with tribromide ion gave a 95% yield of the product substituted in the para position. This product underwent lithium-bromine exchange when reacted with n-butyllithium. The resulting anion was used to prepare PhZPX and PhPX2 derivatives, X p-C6H4NCH2(CH2OCH2)4&12 The oxide of PhZPX was completely characterized by an x-ray diffraction study which showed, in general, that the phosphorus was tetrahedral, the nitrogen planar, and the crown ether ring organized with the oxygen atoms endodentate. Several attemps were made to nitrate or nitrosate the phenyl ring in the parent crown ether. Spectroscopic evidence obtained from the products indicate that the reaction led to mixtures of mono and disubstituted products. / Department of Chemistry
87

The synthesis and study of a crown ether functionalized with both phosphine and phenol groups

Crabill, Todd W. January 2005 (has links)
This study has resulted in a crown ether functionalized with both phosphine and phenol groups, 5-diphenylphosphino-1,3-xylyl-18-crown-5. The target molecule was obtained from a six step synthesis. 4-Bromophenol was treated in sequence with formaldehyde, dimethylsulfate, and phosphorus tribromide producing 4-bromo-2,6-bis(bromomethyl)anisole. The main intermediate, 5-diphenylphosphino-1,3-xylyl-18-crown-5, was obtained by treating 4-bromo-2,6-bis(bromomethyl)anisole in sequence with tetraethylene glycol, lithium iodide, and methyldiphenyl phosphonite. The lithium iodide cleaved the anisole-to-methyl group bond, and the methyldiphenyl phosphonite provided the phosphine group for the crown ether following a lithium bromine exchange reaction. The 31P NMR of the phosphine crown ether showed a single signal at 6 -5.9, showing consistency of a single product. The IH NMR of the phosphine crown ether in deuterated chloroform showed signals at 6 3.55-3.7 (crown CH2), 6 4.6 (benzylic CH2), 6 7.1 (d, J = 7.o Hz, crown aromatic CH2), and 6 7.2-7.4 (noncrown aromatic CH2). / Department of Chemistry
88

The synthesis and characterization of phosphine functionalized crown ethers by use of spectroscopic and x-ray methods

Haddadian, Fereshteh January 1995 (has links)
The phosphine(III) crown ethers, [4'-(N-phenylaza-15crown-5)]3P (1), [4'-(N-phenylaza-l8-crown-6)]3P (2), [4'-(Naza-18-crown-6)]2-Ph-P (3), and [4'-(benzo-15-crown-5)]3P (4) were synthesized by using an electrophilic bromination of the crown phenyl ring (with a tribromide ion) followed by the preparation of a lithium salt and subsequent reaction of the resulting lithiocrowns with P(III) reagents. The oxide of compound 1 was completely characterized by an X-ray diffraction study, which showed that structurally there is not a significant difference in P-O bond distances and OPC bond angles with [4'-(N-phenylaza-15-crown-5)]-Ph2-P=O. Thespectroscopic data of compound 1 and 2 were compared. It appears that 1 and 2 are similar in P environment; also they are more air sensitive than 3 and 4. In addition, a discussion about compounds 1-4, and a literature review of the preparation of phosphines are included. / Department of Chemistry
89

The synthesis and study of 5-oxime-2-methoxy-1,3-xylyl-18-crown-5

Acord, Douglas A. January 2009 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / Department of Chemistry
90

The role of polyamines in crown gall tumor formation

Kulpa, Joan M. January 1983 (has links)
The purposes of this study were to determine the effect of the exogenous polyamines, spermidine and spermidine, on growth of crown gall tumors, to assay levels of spermidine and spermine in normal and crown gall tumor tissue and to determine the effects of selected anti-tumor compounds on growth of crown gall tumors as well as on the endogenous levels of the polyamines in those tumors.Findings1. Spermidine and spermine are present in normal potato tissue and crown gall tumor tissue grown on potato discs.2. Exogenous spermidine and spermine do affect growth of crown gall tumors depending upon the concentration of the solutions added, the type of polyamine added and the number of times the solutions are applied.3. Spermidine (1 mM) has a positive growth effect on crown gall tumors.4. Crown gall tumor tissue contains more spermidine than corresponding normal potato tissue; spermine levels are consistently low compared to spermidine levels in both crown gall tissue and normal potato tissue.5. The level of spermidine in tumor tissue increases as the tumors develop; the level of spermine remains consistently low.6. Addition of methylglyoxal bis (guanylyhdrazone) inhibits tumor growth, but the inhibitory effect is decreased by concurrent administration of spermidine.7. Both novobiocin and nalidixic acid have an inhibitory effect on tumor growth, but the effects are decreased by concurrent administration of spermidine. Reversal of the nalidixic acid effect on growth by addition of spermidine is more pronounced than reversal of the novobiocin effect.8. Methylglyoxal bis (guanylhydrazone) decreases the endogenous levels of both spermidine and spermine in crown gall tumor tissue.Conclusions1. The polyamine, spermidine, plays an important role in the growth of crown gall tumors.2. Compounds which inhibit spermidine biosynthesis or the possible mode of action of spermidine inhibit tumor growth.3. Other polyamines appear to have no significant role in crown gall tumor growth.4. The growth of crown gall tumors involves the activation of a mechanism leading to the increased biosynthesis of spermidine.5. A specific inhibitor of polyamine biosynthesis in animals also reduces endogenous levels of spermidine and spermine in crown gall tumors.6. These data further support the hypothesis that crown gall tumors are similar to animal tumors.

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