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Mossbauer Effect Study of Libyan Desert Silica Glass
(
Qatar University
, 1981 , Article)
The Mossbauer effect and X-ray fluorescence techniques are applied to study the Libyan Desert Silica Glass. The X-ray flourescence proved the existence of 13 elements in each sample of five glass types with differences in ...
Acute Toxicity Of Some Oil Dispersants To Mullet Fry ( Liza Macrolepis) Of The Arabian Gulf
(
Qatar University
, 1986 , Article)
The acute toxicity of Shell LTX, Shell Concentrate, Servo CD 2000 and Exxon OSD 9217 were used to calculate 72 - hr. LC ci\ and toxicity curves to the Mullet Fry ( Liza macrolepis) under the Arabian Gulf conditions (Temp. ...
The Superimprimitive Subgroups Of The Alternating Group Of Degree 8
(
Qatar University
, 1984 , Article)
A transitive permutation group G is called superimprimitive if it is imprimitive with non-trivial block systems of imprimitivity of lengths all the non-trivial divisors of the degree of G; The superimprimitivity concepts ...
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 ...
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 ...
Absolute evaluation of ferrous and ferric concentration in Ca amphibole
(
WILEY-VCH Verlag
, 1982 , Article)
Studies are made of M?sshauer absorption of 57Fe in a Ca-amphibole schist sample at room and liquid nitrogen temperatures. The absolute concentration and the recoilless fraction for ferrous and ferric cations are determined ...
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 ...
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 ...
Phyto-Ecological Observations In Northern Oman
(
Qatar University
, 1985 , Article)
The present study has evolved out of a limited field work during a short visit to Oman. It is an attempt to record more detailed data on the plant communities and their habitat features in three sectors of northern Oman. ...