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17- Hydroxylation Of Progesterone By Cunninghamella Echinulata On A Laboratory Fermentor Scale
(
Qatar University
, 1985 , Article)
The mircrobiological transformation of progesterone by a local isolate of Cunninghamella echiiiulata using a laboratory fermentor was studied. Progresterone (10-50 g/1) wetted by Tween 80 was added to 48-hour old culture ...
Study of A Time Dependent Double -Diffusive Salinity Problem
(
Qatar University
, 1989 , Article)
The time-dependent, double diffusive stability problem for a horizontal layer of salty water bounded by two rigid isothermal surfaces is analyzed using a linear perturbation technique. Initially, the layer is subjected to ...
Constituents of plants growing in Qatar
(
Elsevier
, 1986 , Article)
N/A.
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, ...
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 ...
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 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 ...
Constituents of plants growing in Qatar part XV. Chemical investigation and pharmacotoxicity of pyrrolizidine alkaloids of moltikiopsis ciliata
(
Taylor & Francis
, 1988 , Article)
Chemical study of the alkaloidal constituents of Moltikiopsis ciliata resulted in the isolation and identification of heliotrine and echinatine, in addition to other minor alkaloids. Pharmacological experiments revealed: ...