Browsing Chemistry & Earth Sciences by Publication Date
Now showing items 1-20 of 312
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Synthesis and biological activity of some new 3-and 6-substituted coumarin amino acid derivatives. Part I
( Wiley-Blackwell , 1981 , Article)The synthesis of 6-nitrocouarrain-3-CO-amino acids and their corresponding methyl esters (II-XVII) and some dipeptide methyl esters (XVIII-XXVI) are described. 6-(N-Tosyl- or N-phthalylaminoacyl)aminocoumarin-3-carboxylic ... -
Synthesis and biological activity of some new aminoacylcarbazole derivatives. Part I
( Wiley-Blackwell , 1982 , Article)The syntheses of different 9-(N-phthalyl- or N-tosyl- or free aminoacyl)carbazoles and the corresponding derivatives of 3,6-dinitrocarbazoles and some derivatives of 3,6-diamino-9-(N-phthalylaminoacyl)carbazoles (II-XXXII) ... -
Polarization Resistance Study on Copper Corrosion in Aqueous Potassium Hydrogen Phthalate Solution
( WILEY-VCH Verlag , 1987 , Article)The effect of temperature on corrosion of copper in 0.1 M aqueous solution of potassium hydrogen phthalate (KHPh) has been investigated using polarization resistance technique. it was found that that the corrosion rate in ... -
Substituted phenols as corrosion inhibitors for copper in nitric acid
( WILEY-VCH Verlag GmbH , 1988 , Article)The dissolution of copper in nitric acid solution in the presence of resorcinol, o, p-aminophenols, catechol, o-cresol and salicylaldehyde as corrosion inhibitors has been studied by galvanostatic polarization and weight ... -
Evidence for some prostaglandins in Allium sativum extracts
( John Wiley & Sons, Ltd. , 1988 , Article)Homogenized garlic (Allium sativum Linn.) was extracted successively with organic solvents and the prostaglandin-rich fraction separated. Fractionation of the extract with column chromatography was performed. TLC of the ... -
Chemical survey of some plants Growing in Qatar
(1989 , Other)Fifty one plants growing in Qatar, belonging to thirty families, were surveyed for alkaloids, anthraquinones, coumarins, flavonoids, tannins and saponins. The medicinal uses of these plants arereported. -
Inhibitive Effect of Butyltin Trichloride on Dissolution and Localized Corrosion of Aluminium in Sodium Hydroxide and Hydrochloric Acid
( WILEY-VCH Verlag , 1990 , Article)The dissolution of aluminium in sodium hydroxide and hydrochloric acid in the presence of butyltin trichloride as corrosion inhibitor has been studied by hydrogen evolution and thermometric methods. Experimental findings ... -
Guaianolides from Centaurea sinaica
( Elsevier , 1990 , Article & Report)Three sesquiterpene lactones were isolated from the aerial parts of Centaurea sinaica: amberboin, chlorohyssopifolin A and sinaicin. The latter is reported for the first time. -
Metathesis ring opening polymerization of 5,6-dimethylenebicyclo[2.2.1]hept-2-ene
( John Wiley & Sons, Ltd , 1992 , Article)5,6-Dimethylenebicyclo[2.2.1]hept-2-ene (I) polymerizes in the presence of the two-component ring opening metathesis polymerization (ROMP) initiators WCl6/(CH3)4Sn and MoCl5/(CH3)4Sn. The product polymers were insoluble ... -
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). ... -
Flavonoids from Centaurea sinaica
(1992 , Article)Four Newly isolated flavonoids from Centaurea sinaica -
The amino acid composition of some Common marine algae from Qatar (Arabian Gulf)
( Qatar University , 1993 , Article)The most dominant twenty algal species representing the main three groups of benthic macroalgae, Chlorophyceae, Phaeophyceae and Rhodophyceae were collected from the coastal zones of the Qatar peninsula. The algae were ... -
Triterpenoids from Salvia aegyptiaca
(1993 , Article)Newly isolated secondary metabolites from Salvia aegyptiaca growing in Qatar -
Glycosides of Heterocycles: A Direct Route to 1-(β-D-Glycopyranosyl)pyridinethione Nucleosides
( WILEY-VCH Verlag , 1994 , Article)A novel synthesis of 1-(β-d-glycopyranosyl)pyridinethione nucleosides 6 utilizing pyridine-2(1H)-thiones 3 and α-halogeno sugars 4 as starting components is reported. -
Kinetics and mechanism of H2O2 decomposition by Cu(II)-, Co(II)-, and Fe(III)-Amine complexes on the surface of Silica-Alumina (25% Al2O3)
( John Wiley & Sons, Inc. , 1994 , Article)The kinetics of the H2O2 decomposition by Cu(II)-, Co(II)-, and Fe(III)-amine complexes supported on the surface of silica-alumina (25% Al2O3) catalyst have been investigated. The decomposition process proceeded with ... -
Constituents of plants growing in qatar xxv flavonoids of Picris Radicata (forssk.) Less.
( Qatar University , 1994 , Article)Four flavonoids were isolated from the plant and were identified as apigenin, chrysin 7-glucoside, leuteoline and luteolin 7-glucoside. -
Mercury pollution in doha (Qatar) coastal environment
( Wiley Periodicals, Inc. , 1994 , Article)Surface water and sediment samples were collected from the Doha coastal area and analyzed for content of physico-chemical forms of mercury. Dissolved reactive Hg (2.9 ng L?1) represented 81.0% of the total dissolved Hg ... -
Biochemical And Environmental Studies On Hepatoma Patients In Egypt
( Qatar University , 1994 , Article)The present study was carried out on 102 hepatoma patients collected mainly from the National Cancer Institute, Cairo University, during the period 1988-1991 . Environmental and personal data were collected for each patient. ... -
REMOTE MONITORING AND CONTROL OF MICROCOMPUTER RAISED DATA ACQUISITION SYSTEMS
( Blackwell Publishing Ltd , 1994 , Article) -
Flow injection potentiometric determination of harmine and harmaline hallucinogens
( Wiley-VCH Verlag , 1995 , Article)Flow injection analysis (FIA) systems incorporating potentiometric sensors for harmine and harmaline hallucinogens are described. The sensors are based on the use of harmine and harmaline tetraphenylborate or reineckate ...