College of Arts & Sciences: المرسلات الحديثة
السجلات المعروضة 501 -- 520 من 3563
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Constituents of plants growing in Qatar
( Elsevier , 1986 , Article)N/A. -
Constituents of plants growing in Qatar XVII anti-inflammatory and cytotoxic activities of extracts of thirty indigenous species
( Taylor & Francis , 1990 , Article)Thirty plants, indigenous to Qatar, were extracted separately with hexane, chloroform and ethanol. The dried extracts were examined for potential anti-inflammatory activities both in vitro by their ability to inhibit ... -
Constituents of plant growing in Qatar. II. Investigation of Euphorbia granulata
(1982 , Article)N/A. -
Constituents of plants growing in Qatar III - Nutritive constituents of Garawah (Glossonema edule)
( Junk Publishers , 1983 , Article)Both the pericarp and the unripe seeds of the unripe fruits of Glossonema edule were separately analysed. The crude protein content of the unripe seeds is double that of the pericarp. Investigation of the amino acids of ... -
Constituents of plants growing in qatar V. Constituents of the volatile oil of cymbopogon parkeri
( Elsevier , 1983 , Article)Analysis of the volatile oil of Cymbopogon parkeri has been carried out by capillary gas chromatography-mass spectrometry. To facilitate identification, prefractionation of the oil by adsorption high-performance liquid ... -
Constituents of plants growing in Qatar VII an examination of certain plants for anti-inflammatory activity
( Taylor & Francis , 1985 , Article)Six desert plants native to the State of Qatar were successively extracted with hexane, chloroform and ethanol. These extracts were examined for their ability to inhibit aggregation of rabbit blood platelets induced by ... -
Iridoids and flavonoids of Teucrium polium herb
( Thieme , 1986 , Article)The iridoid glycoside teucardoside and the flavonoids salvigenin and cirsiliol have been isolated from Teucrium polium var. pilosum and T. polium var. alba. The medicinal significance of these findings is discussed. -
Constituents of plants growing in Qatar IX. The antispasmodic components of cymbopogon parkeri stapf. Parkeri stapf
( Taylor & Francis , 1986 , Article)Investigation of the lipid fraction of Cymbopogon parkeri revealed the presence of several active constituents, one of which possesses an antispasmodic activity and was identified as cryptomeridiol. Study of the other ... -
Amphetamine Selective Electrodes Based on Dibenzo-18-crown-6 and Dibenzo-24-crown-8 Liquid Membranes
( American Chemical Society , 1989 , Article)Two novel membrane electrodes highly sensitive and selective for amphetaminium cation are developed and electrochemically evaluated according to IUPAC recommendations. These electrodes Incorporate amphetamine-dibenzo-18-crown-6 ... -
Selective determination of thiamine (vitamin B1) in pharmaceutical preparations by direct potentiometric argentometric titration with use of the silver-silver sulphide ion-selective electrode
( Elsevier , 1989 , Article)A simple and selective argentometric titration method is described for determination of thiamine (vitamin B1), based on direct potentiometric titration in alkaline media (⩾0.5M) in which a chemical transformation takes ... -
Liquid membrane electrodes for the selective determination of nicotine in cigarette smoke
( The Royal Society of Chemistry , 1989 , Article)Five liquid membrane electrode systems responsive to the nicotinium cation are described. These electrodes are based on the use of the ion-association complexes of the nicotinium cation with tetraphenylborate, 5-nitrobarbiturate, ... -
Solid-state planar microsensors for selective potentiometric determination of ethylmorphine
( Marcel Dekker Inc. , 1999 , Article)The potentiometric performance characteristics of microelectronically fabricated solid-state planar ethylmorphine sensors based on silicon/silicon nitride substrate and a mixture of ethylmorphine-tetraphenylborate and ... -
Spectrophotometric Determination of Hydrogen Peroxide by a Hydroquinone-Aniline System Catalyzed by Molybdate
( Korean Chemical Society , 2004 , Article)In this system hydroquinone is oxidized to pbenzoquinone by H2O2. 2 aniline are added, in successive stages, to pbenzoquinone, to yield the disubstituted quinone as the final product. 20 The UV-VIS spectrum of the product ... -
Thiamine-reineckate liquid membrane electrode for the selective determination of thiamine (vitamin B1) in pharmaceutical preparations
( The Royal Society of Chemistry , 1989 , Article)The construction and electrochemical response characteristics of a liquid membrane electrode for thiamine (vitamin B1) based on the formation of an ion pair between the thiamine cation and the reineckate anion in nitrobenzene ... -
Poly(vinyl chloride) matrix membrane electrodes for manual and flow injection determination of metal azides
( The Royal Society of Chemistry , 1992 , Article)Novel poly(vinyl chloride) matrix membrane electrodes for the azide ion are developed, electrochemically evaluated and used for manual and flow injection determinations of soluble and insoluble metal azides. These electrodes ... -
Nitron tetrachloroaurate(III) electrodes with poly(vinyl chloride) and liquid membranes for the selective determination of gold
( Elsevier , 1991 , Article)PVC matrix and liquid membrane electrodes have been developed for direct potentiometric determination of gold(III). The membranes incorporate nitron tetrachloroaurate(III) as electroactive material. Fast response for ... -
Determination of amitriptyline, imipramine and orphenadrine in antidepressant drugs by potentiometry, spectrophotometry and atomic absorption spectrometry
( Springer-Verlag , 1993 , Article)Methods are described for the determination of amitriptyline, imipramine and orphenadrine in some antidepressant drugs. They are based on a prior reaction with ammonium reineckate to form 1∶1 water-insoluble drugreineckate ... -
Liquid and poly (vinyl chloride) matrix membrane electrodes for the selective determination of cocaine in illicit powders
( Elsevier , 1992 , Article)The construction of liquid membrane and PVC matrix-type cocainium ion selective electrodes and their use for direct potentiometry and potentiometric titration of cocaine are described. The ion-pair complexes of cocaine ... -
Determination of glafenine in dosage forms and serum by thin layer densitometry and high performance liquid chromatography
( Elsevier , 1997 , Article)New thin layer densitometry and high performance liquid chromatography (HPLC) methods are described for quantitative determination of glafenine in dosage forms in the presence of its photo-degradation products and in serum ...