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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 ...
Sesquiterpene lactones from Pulicaria sicula
(
Elsevier
, 1988 , Article)
The aerial parts of Pulicaria sicula afforded the known xanthanolides 1-6, the guaianolides 7 and 8 as well as two new ones, the lactone 9 and the corresponding epoxide 10. Furthermore nerylisobutyrate and the thymol ...
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.
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 ...
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 ...
Inhibitory effect of sodium nitrite on corrosion of lead in 0.1 M sodium hydroxide solution
(
Council of Scientific and Industrial Research
, 1988 , Article)
The effect of NaNO2 as an inhibitor for corrosion of lead in 0.1 M NaOH solution has been investigated at different temperatures using the Tafel plot technique. The concentrations of NaNO2 employed are in the range 1-5×10-5. ...
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 ...
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.
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 ...
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 ...