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Now showing items 11-20 of 32
Mössbauer effect study of Li21+Me4+Fe63+O122−spinels
(
Baltzer Science Publishers, Baarn/Kluwer Academic Publishers
, 1986 , Article)
Mossbauer effect spectra are obtained for the cubic ferrites Li2 Me Fe6 O12 (where Me4+ is one of the tetravalent elements Ge, Si and Ti) at 78K up to their magnetic transition temperatures. In a rather large temperature ...
Mössbauer study of ZnxNi5/3−xFe1Sb1/3O4 spinel ferrite
(
Springer Verlag
, 1985 , Article)
The antimony substituted nickel ferrite ZnxNi5/3–xFe1Sb1/3O4 with different values ofx are prepared, checked by x-ray and studied with57Fe Mössbauer spectroscopy over a wide temperature range. Characteristic spectra of ...
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 ...
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.
A short critique of the Crescent English Course
(
Qatar University
, 1988 , Article)
This paper is a short critique of the "Crescent English Course", Pupils Book 2. It falls into two parts. The first is information about the course; its aims, organization and some of its general characteristics. The second ...
A study of the interlanguage of some Arabic students of English
(
Qatar University
, 1988 , Article)
In this study, the contrastive analysis method is used to investigate the lnterlanguage (IL) developmental sequences of the acquisition of some aspects of English by Arabic-speaking learners. The learners, whose language ...
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: ...
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 ...
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 ...