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The Structures And Mode Of Formation Of Some Cyclodiphosphazane Derivatives With Urea And Thiourea
(
Qatar University
, 1986 , Article)
The methods of preparation and possible reaction mechanisms for the formation of some geminal and nongeminal aminocyclodiphosph (v) azanes of the type (II - V) are discussed. These cyclodiphosphazanes obtained from the ...
The electrical and optical properties of poly (4-ethylidene-l, 3-cyclopentylene vinylene)
(
Qatar University
, 1989 , Article)
The intrinsic viscosity, electrical conductivity and IR absorbance were measured for the sample of poly (4—ethylidene—1, 3—cyclopentylene vinylene). The sample is strongly oxidized in air. Under vacuum the activation energy ...
Dehydration of Ethanol over HF-treated Al2 O3 using the GC-column as Chemical Reactor
(
Qatar University
, 1981 , Article)
The effect of treating •y-alumina with hydrofluoric acid on the dehydration reaction of ethanol was investigated at 325°C. The gas chromatographic column was used as a chemical reactor. The rate of formation of ethylene ...
A New Tetrafluoroborate Liquid Membrane Electrode For Selective Determination Of Boron
(
Qatar University
, 1986 , Article)
The construction and performance characteristics of a new liquid membrane electrode selective for BF^ion are herein described. The electrode incorporates nitron-tetrafluoroborate ion pair complex in nitrobenzene as a liquid ...
Influence Of Surface Finish Parameters On Corrosion Of Zinc
(
Qatar University
, 1989 , Article)
The effect of surface parameters on corrosion behaviour of pure zinc in sodium sulphate solution was investigated. Surface parameters were determined using a Talysurf surface analyzer, and corrosion testing was performed ...
Pyrrolizidine Alkaloids From Senecio Aegyptius L.
(
Qatar University
, 1988 , Article)
Investigation of the alkaloidal constituents of Senecio aegyptius L. resulted in the isolation and identification of senecionine, dehydrosenkirkine and probably an isomer of seneciphylline. TLC, HPLC and GLC showed the ...
Solvent Effects Of The Oxidation Of Iron (II) - Tartrate Complex By Molecular Oxygen In Aqueous Solutions Of Alcohols
(
Qatar University
, 1985 , Article)
The solvent effects on the oxidation of Fe(II)-tartrate by molecular oxygen have been investigated in aqueous acidic solutions of alcohols such as methanol, ethanol, isopropanol and t-butanol. The second-order rate constant ...
Ecological and phytochemical studies on the "miswak", salvadora persica l.
(
Qatar University
, 1984 , Article)
The "Miswak", which is produced from the stolons and branches of Salvadora persica is used as a substitute for ordinary tooth brushes. The use of "Miswak" has been recommended by Islam. It is endowed by several characteristics ...
Copper Complexes Of Di-, Tri-, And Tetra-Peptides Containing Tryptophan, Histidine And Arginine
(
Qatar University
, 1983 , Article)
Fifty Seven copper complexes of di-, tri-. and tetra-peptides containing tryptophan, histidine and arginine are studied spectrophotometrically. The ^a, and colour of the complexes are dependent on the sequence of the amino ...
Spectroscopic Studies On Some Methylphosphonothioic Diamides And Related Compounds
(
Qatar University
, 1987 , Article)
A series of methylphosphonothioic diamides MrP (S) (NHR)., ( R = Mr, pr' and Bu') and some related compounds viz, PhP(S)(NHBu)a ,P1^P(S) ( NHCHJ'h ) arc preparpd and their infrared, n.m.r. and mass spectra arc- recorded. ...