Browsing Qatar University Science Journal - [From 1981 TO 2007] by Subject "Chemistry"
Now showing items 1-20 of 95
-
Adsorptive Properties of a Desert Salsola Vermiculate Species from Synthetic Aqueous Solutions
( Qatar University , 2006 , Article)Pollution is becoming a major environmental problem and the current trend is to use available biomass to remove toxic substances from aqueous solutions. The preliminatry adsorption results on a natural Salsola Vermiculata ... -
Aminoacid derivative? With psychotogenic activity by
( Qatar University , 1989 , Article)As a part of an extensive programme concerned with the syntheses and investigation of a group of benzilyl-aminoacid and diphenylacetylaminoacid, piperidine esters possessing psychotogenic properties, attention has been ... -
Analytical Studies Of Some Controlled And Noncontrolled Drugs Of Abuse
( Qatar University , 1991 , Article)Separation and identification of some depressants and stimulants by GLC, combined GC-MS and HPLC techniques was attempted. The results obtained are successful, valuable and may be applied in routine forensic analysis. -
Analytical Studies Of Some Controlled And Noncontrolled Drugs Of Abuse (II)
( Qatar University , 1993 , Article)Benzodiazepines, barbiturates, amphetamines and some other non-controlled drugs were identified by GLC and HPLC then confirmed by GC-MS techniques. Comparative studies and discussions on the results obtained by GLC and ... -
Application of Stripping Voltammetry for the Determination of Cadmium, Lead, Copper and Zinc in Yemani soils and Vegetables
( Qatar University , 2004 , Article)Heavy metals contents in the solutions from acid digestion of Yemeni soils and vegetables were deter¬mined by differential pulsed anodic stripping voltammetry. The geometric mean for Cd, Pb, Cu and Zn concentrations for ... -
Biochemical Characterization Of Human Schistosomes And Their Molluscan Hosts By Electrophoretic Techniques
( Qatar University , 1994 , Article)The recent application of biochemical techniques in taxonomy markedly improved the specific identification and strain characterization of a wide range of living organisms. These techniques are gradually replacing classical ... -
Biochemical studies on the blood and tissue components of the common Egyptian toad bufo regularis
( Qatar University , 1995 , Article)The effect of insulin and/or cortisone on the blood, serum and tissue levels of glucose, glycogen, pyruvic acid, lactic acid cholinesterase, alkaline phosphatase, aspartate amino transferase (AST), alanine amino-transferase ... -
The Complexation of Lanthanides by Azo-B-Diketones Stability Constants
( Qatar University , 1982 , Article)The stability constants of the complexes between the trivalent lanthanide series of cations and series of azo-B-diketone ligands are reported. The measurements were conducted at 30°C and zero ionic strength (free KN03), ... -
Conductance Measurements in Corrosion Studies of Aluminium
( Qatar University , 1994 , Article)A new method is suggested for studying the rates of dissolution of oxide film on aluminium and its alloys. The method is based on measuring the conductance between two aluminium (or its alloys) electrodes immersed in 3.0 ... -
Constituents of catha edulis (alkaloids, triterpenoids and related substances and saponins)
( Qatar University , 1989 , Article)The study of the alkaloids of khat samples from Egypt and Yemen revealed qualitative and quantitative differences. Cathine and the dimer of cathinone occured in both samples, while norephedine was detected only in Yemen ... -
Constituents Of Centaurea Species
( Qatar University , 1992 , Article)A comprehensive review of Centaurea species including all the isolated consituents is given. The biological activities of the studied species are also reported. -
Constituents Of Cymbopogon Species
( Qatar University , 1986 , Article)A comprehensive review of the Cymbopogon species including the essential oils and their constituents is given. An account of the other components viz. non volatile terpenoids and phenolic compounds is also given. The ... -
Constituents Of Green Beans Phaseolus Vulgaris (Lipids And Flavonoids)
( Qatar University , 1992 , Article)Chemical study of the lipid fraction resulted in the isolation and identification of a hydrocarbon fraction (n-Czg -0-033); an aliphatic alcohol fraction (C^, Czp, €30) and a sterol fraction (stigmasterol and sitosterol). ... -
Constituents of plants growing in qatar part xxvii: flavonoids Of cymbopogon parkeri
( Qatar University , 1995 , Article)The study of the flavonoids of Cymbopogon parkeri resulted the isolation and indentification of tricin and isoorientin. Three other flavonoids have been isolated and partially identified. -
Constituents of plants growing in qatar x.* seasonal variations of the volatile oil of cymbopogon parkeri
( Qatar University , 1985 , Article)The seasonal variation of the volatile oil of Cymbopogon parkeri Stapf. was studied. The oil content is higher during the hot dry season than during the humid hot season and the cold season. No qualitative differences among ... -
Constituents of plants growing in qatar xxiii. Flavonoids of francoeuria crispa
( Qatar University , 1993 , Article)Investigation of the flavonoid constituents of Francoeuria crispa, resulted in the isolation and identification of four flavonoids: quercetin, qucrcetin-3-O-gIucoside, quercetin-7-0-glucoside and quercetin-3-methyl ether. -
Constituents of plants growing in Qatar xxiv phytochemical investigation of salvia aegyptiaca L.
( Qatar University , 1994 , Article)The study of the flavonoids revealed the isolation and identification of luteolin, luteolin 7-O- glucoside, apigenin and apigenin 7-0 glucoside; their identity was proved by m.p., TLC, UV, IR and MS. Moreover, a coumarin ... -
A convenient synthesis of Carbocyclic fused Thieno [2,3-b] Pyridines and Carbocyclic fused IH-Pyrazolo [3,4-b] Pyridines
( Qatar University , 2001 , Article)A synthesis of Carbocyclic fused thieno [2,3-b] pyridines and carbocyclic fused 1H- pyrazolo [3,4-b] pyridines utilizing car-bocyclic fused 2(lh)-pyridinethiones as starting components is described. The structures of the ... -
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 ... -
Corrosion of n-GaAs/aqueous Photoelectrochemical Cell
( Qatar University , 2005 , Article)A combination of electrochemical studies, scanning electron microscopy, SEM, and light reflectivity measurements reveals information about the corrosion of enlightened n-GaAs in various aqueous electrolytes. The corrosion ...
