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Constituents of plants growing in qatar xxiii. Flavonoids of francoeuria crispa
(
Qatar University
, 1993 , Article)
Investigation of the flavonoid constituents of Francoeuria crispa, resulted in the isolation and identification of four flavonoids: quercetin, qucrcetin-3-O-gIucoside, quercetin-7-0-glucoside and quercetin-3-methyl ether.
Thermogravimetry and infrared spectroscopy Of Moroccan oil shales in an oxidative Dynamic atmosphere
(
Qatar University
, 1994 , Article)
Thermogravimetric analyses were carried out on raw Timahdit (Morocco) oil shales and its demineralisation products in an oxidative atmosphere. The kerogen was isolated by successive HCl, HF and float-sink separation ...
Evaluation of Electron Swarm Parameters in SF6 Using Monte Carlo Method
(
Qatar University
, 2005 , Article)
The motion of electrons in sulfur hexafluoride (SFo) in uniform electric fields is simulated using a Monte Carlo method. The swarm parameters are evaluated and compared with experimental results of drift velocity, electron ...
Constituents Of Green Beans Phaseolus Vulgaris (Lipids And Flavonoids)
(
Qatar University
, 1992 , Article)
Chemical study of the lipid fraction resulted in the isolation and identification of a hydrocarbon fraction (n-Czg -0-033); an aliphatic alcohol fraction (C^, Czp, €30) and a sterol fraction (stigmasterol and sitosterol). ...
Synthesis And Biological Activity Of Some New 4-(Aminoacyl) Aminopyridines And 2-(Aminoacyl) Aminopyrimidine Derivatives
(
Qatar University
, 1983 , Article)
The synthesis of 4-(N-Tos and N-Pht-aminoacyI) aminopyridines (III - XIV) and 2-(N-Pht-aminoacyl)-aminopyriniidines (XV-XXIV) has been achieved employing the acid chloride and carbodiimide methods. Hydrazinolysis of ...
Mechanism of Dehydration of Ethanol over Alumina
(
Qatar University
, 1981 , Article)
The dehydration reaction of ethanol to ether and ethylene was kinetically investigated in a flow system using •y-alumina. Pyridine was found to inhibit the formation of ethylene and ether. The rate of ethylene formation ...
Analytical Studies Of Some Controlled And Noncontrolled Drugs Of Abuse (II)
(
Qatar University
, 1993 , Article)
Benzodiazepines, barbiturates, amphetamines and some other non-controlled drugs were identified by GLC and HPLC then confirmed by GC-MS techniques. Comparative studies and discussions on the results obtained by GLC and ...
Facile synthesis of several new pyridine and fused pyridine derivatives with Anticipated biological activity
(
Qatar University
, 1994 , Article)
The reactions of benzothiazol-2-N-acetylacetohydrazide 1 with a, (}-unsaturated aldehyde, ketone, ester or diketoester led to the formation of the titled ring systems. The same target was also achieved through the reactions ...
Corrosion of n-GaAs/aqueous Photoelectrochemical Cell
(
Qatar University
, 2005 , Article)
A combination of electrochemical studies, scanning electron microscopy, SEM, and light reflectivity measurements reveals information about the corrosion of enlightened n-GaAs in various aqueous electrolytes. The corrosion ...
Vibrational Analysis Of TaBr5
(
Qatar University
, 1987 , Article)
Vibrational analysis for TaBr5 is achieved on the basis of D3h symmetry and employing GF matrix method. Each vibration is quantitatively assigned according to the calculated values of the potential energy distributions. ...