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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

The sorption of water-soluble cellulose ethers by cellulose.

Shriver, Ellsworth H. (Ellsworth Harold) 01 January 1950 (has links)
see pdf
82

The effects of ozone upon a lignin-related model compound containing a beta-aryl ether linkage

Balousek, Peter J. (Peter Joseph) 01 January 1979 (has links)
No description available.
83

Unambiguous Evidence of Hydrogen Bonds from Nuclear Magnetic Resonance Spectroscopy

Hong, Yu-Wen 19 August 2002 (has links)
Use of hydrogen bonding as internuclear connecting information to better determine molecular structure or dynamics.
84

Substitution, elimination, addition, and rearrangement reactions promoted by potassium salts solubilized by 18-crown-6 ("naked" anions) in non-polar and dipolar aprotic organic solvents

Dabdoub, Atif Musa 12 1900 (has links)
No description available.
85

Improvements on the synthesis of vinyl crown ethers

Kleissler, Charles Richard January 1982 (has links)
No description available.
86

Computer modelling of calixerene compounds capable of selectively extracting lanthanide metals from nuclear waste slurries

Leeson, Philip January 1996 (has links)
No description available.
87

Studies of fluxional characteristics of organic ligand complexes

Quereshi, K. B. January 1987 (has links)
No description available.
88

The preparation and study of new metal binding reagents

Mbadike, Okey Patrick January 1990 (has links)
New phosphine ligands which also contained crown ether groups were synthesized by condensing two main reagents. Reagent A was Ph2P(CH2)3NH2 and it was prepared by reductingPh2P(CH2)2CN with LiALH4 in diethyl ether. Ph2P(CH2)2CN is obtained by reacting Ph2PH and CH2=C(H)CN in a Michael-type reaction. Reagent B, 4-formyl-benzo-15-crown-5, was obtained from the reaction of 3,4 dihydroxybenzaldehyde with 1,11 dichloro-3,6,9 trioxoundecane.By condensing the benzaldehyde crown ether and the phosphine amine, a Schiff-base type crown ether containing both P(III) and N(III) centers was obtained. Spectroscopic studies of the ligand and its Pd(II) derivative have shown PdCl2[Ph2P.(CH2)3N CH-C6H3(OMe)2]2 were characterized by that metal binding occurred exclusively on the P( III) center.A model ligand was synthesized by condensing 3,4-dimethoxybenzaldehyde with Ph2P(CH2)3NH2 to obtain an analogous product. Both ligands, Ph2P(CH2)3N=CH-benzo-15crown-5 and Ph2P(CH2)3N=CH -C6H3(OMe)2 and their palladium derivatives, PdCl2[Ph2P(CH2)3N=CH-benzo-15-crown-5]2 and spectroscopic and elemental analysis. The Pd(II) derivatives were synthesized from the reactions of (Ph2CN)2)PdC12 with the ligands. / Department of Chemistry
89

Synthesis and study of dibenzodihydroxy-26-crown-8

Amoozgar, Zohreh January 2007 (has links)
The objective of this research was to synthesis dibenzo-dihydroxy-26-crown-8 (1) as an ionophore for variety of chemosensors. Complexation of the ionophore (1) to a cation would cause a change of conformation. The conformational changes could affect fluorescence, UV spectra and/or Carbon-13 NMR of the chemosensor, depending on the fluorophores attached to the hydroxyl groups of crown 1 and/ or the identity of the ion. Several synthetic routes for crown 1 formation are given in the proposed synthetic procedure. Bis-1,2[2-hydroxyethoxy]benzene (17), bis-1,2[2-(3-chloro-2-hydroxypropoxy)ethoxy]benzene (18), bis-1,2[2-(2,3-epoxypropoxy)ethoxy]benzene (19) and bis-1,2[2(3-chloro-2-oxopropoxy)ethoxy]benzene (22) were synthesized. The reaction of 17 and 19 was attempted in the presence of SnC14, basic and acidic conditions, and in several solvents. The reaction of 17 and 22, and the reaction of 17 and 1,3-dichloroacetone were attempted in various reaction conditions. Crown 1 may have formed in the reaction of 17 and 19 in methylene chloride/ toluene in the presence of SnCl4 as the Lewis acid. / Department of Chemistry
90

Solid-acid catalysed reactions with epoxides and allyl aryl ethers

Elings, Jacob Antonius, January 1900 (has links)
Thesis (doctoral)--Technische Universiteit Delft, 1997. / Vita. Includes bibliographical references.

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