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Now showing items 21-30 of 96
Petrographic Studies of the Alamein Dolomite (Lower Cretaceous) in El-Razzak Oil Field, Western Desert, Egypt
(
Qatar University
, 1982 , Article)
The origin and environment of deposition of the Alamein Dolomite in the El-Razzak Oil Field have been investigated by means of petrographic, chemical and X-ray analysis.
The studied rocks are composed of dolomite with ...
Stability Constants of Lanthanide Complexes with some Structurally Related Organic Ligands
(
Qatar University
, 1982 , Article)
The stability constants of the complexes formed between trivalent lanthanide ions and related carboxyphenylhydrazo-B-diketones ligands are repoted, at 30 °C and at constant ionic strength (0.1 KN03), in 75 % dioxane-water. ...
Studies on Soil Cements : 2 — Physicochemical Properties of the Hardened Soil Cement Pastes.
(
Qatar University
, 1982 , Article)
Various hardened soil-cement pastes were prepared from dry mixtures of montmorillonite clay and portland cement clinker by using different W/C ratios of 0.20, 40, 0.60 and 0.80 and cured in air for various ages. Compressive ...
Phytochemical investigation of thymus decassatus l. 1. Flavonoids and volatile oil
(
Qatar University
, 1993 , Article)
Investigation of the flavonoidal constituents of Thymus decassatus, L. resulted in the isolation and identification of thymonin, 5,6,4'-trihydroxy-7,3'-dimethoxyl flavone, and apigenin. Investigation of the volatile oil ...
Window Analysis Optimization Of Gas Chromatographic Separation Using Different Polarity Packed Columns
(
Qatar University
, 1996 , Article)
Window diagram theory has been described by Purnell and his research team in various publications. In this paper we apply this theory to optimize a separation of complex mixture containing propylene oxide, 1-hexene, ...
Evaluation of Some Local Egyptian Plants as a Source of Chlorophyll Pigments
(
Qatar University
, 1994 , Article)
Four plant materials viz. Spinacia oleracae Linn, (spinach), Beta vulgaris Limm (chard), Medicago sativa Linn, (alfalfa) and Petroselinum sativum Hoff. (parsely) were studied as local sources for the preparation of chlorophyll ...
Some Adsorption Characteristics of Sodium decyl and dodecyl Sulphates on the surface of Emulsifier-free Polymer Latex Particles
(
Qatar University
, 1997 , Article)
The adsorption characteristics of sodium decyl and dodecyl sulphates on polystyrene latex particles have been investigated.
The study involves the addition of known amounts of the surfactant to an emulsifier-free latex, ...
Influence Of Surface Finish Parameters On Corrosion Of Zinc
(
Qatar University
, 1989 , Article)
The effect of surface parameters on corrosion behaviour of pure zinc in sodium sulphate solution was investigated. Surface parameters were determined using a Talysurf surface analyzer, and corrosion testing was performed ...
Oxidative Addition Reactions of Sn(II) And Pb(II) with Some Hydrazide And Hydrazone
(
Qatar University
, 2000 , Article)
Bivalent tin compounds can be easily transformed to tetravalent compounds by oxidizing agents. The use of ortho-quinones for oxidation of transition metals has been the subject of many publications, but few analogous studies ...
Pyrrolizidine alkaloids from alkanna orientalis (L.) Boiss
(
Qatar University
, 1992 , Article)
Three pyrrolizidine alkaloids; 7-angelyl retronecine (I), 9-angelyl retronescine (II), and dihydroxytriangularine (III) were isolated by DCCC and VLC from Alkanna orientalis growing in Egypt. Their structures were elucidated ...