Browsing Qatar University Science Journal - [From 1981 TO 2007] by Subject "الكيمياء"
Now showing items 21-40 of 86
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Detection Of Small Amounts Of Lard In Other Animal Fats
( Qatar University , 1993 , Article)The composition of fatty acids at the b-position (B-FA) and a, a' -positions of the. triacylglycerol was used to establish new criteria for the detection of small amounts of lard in other fats. Determination of P-FA was ... -
Direct Electrochemical Synthesis of Mono, Bi And Polynuclear Complexes of Some Hydrazide and Hydrazone Derivatives
( Qatar University , 2000 , Article)Transition metal complexes of mono-, di- and tetrahydrazides and their hydrazones have been prepared by electrochemical techniques using the metal as a sacrifical anode. The electrochemical oxidation of Co, Ni and Cu in ... -
Ecological and phytochemical studies on the "miswak", salvadora persica l.
( Qatar University , 1984 , Article)The "Miswak", which is produced from the stolons and branches of Salvadora persica is used as a substitute for ordinary tooth brushes. The use of "Miswak" has been recommended by Islam. It is endowed by several characteristics ... -
Effect Of Ca++ And Mg++ On The Binding Of Cytoplasmic And Nuclear Estradiol Receptors In Breast Cancer Of Female Patients
( Qatar University , 1993 , Article)Specific estradiol receptors were quantitatively determined in the cytosol and nuclear fractions of four cancerous breast tissues and one normal uterus. Validated methods are described for estradiol receptor assay. The ... -
Effect of Different Doses of Inorganic Fertilizer on Water Quality, Primary Productivity and Production of Nile Tilapia (Oreochromis niloticus) in Earthen Ponds
( Qatar University , 2002 , Article)Earthen ponds (surface area 155 m2 each) were used to study the effect of different doses of inorganic fertilizer on water quality and fish production. Each pond was stocked with 150 fish of Nile tilapia; Oreochromis ... -
Effect Of Gossypol, Apogossypol And Gossypolone On Fertility Of Male Rats And In Vitro Sperm Motility
( Qatar University , 1993 , Article)The effect of the naturally occurring polyphenolic pigment, gossypol, and some of its metabolites, apogossypol and gossypolone, on the fertility of male rats has been studied in vivo. The normal growth of the rats was ... -
Effect of plastic deformation on Corrosion of cadmium in 0.1 m sodium Sulphate solution
( Qatar University , 1993 , Article)The present investigation was carried out to study the influence of prior plastic deformation and surface finish on the corrosion behaviour of pure cadmium in 0.1 M Na2SC>4 solution at 25° C. Cylindrical specimens were ... -
The effect of two substituents on different Organoselenides and tellurides to form new charge - transfer complexes
( Qatar University , 1999 , Article)Different organotellurides and selenides were prepared as electron donors and reacted with p-Benzoquinone (p-BQ) and m-Dinitrobenzene (m-DNB) as electron acceptors. The resulted molecules were considered as new charge ... -
The effects of sea water immersion on the mechanical properties of low density polythylene
( Qatar University , 1997 , Article)The effects of immersion of low-density polyethylene (LDPE) m seawater for times of up to one year were studied using mechanical and ultrasonic techniques. The studies were carried out in the laboratories of the Faculties ... -
The electrical and optical properties of poly (4-ethylidene-l, 3-cyclopentylene vinylene)
( Qatar University , 1989 , Article)The intrinsic viscosity, electrical conductivity and IR absorbance were measured for the sample of poly (4—ethylidene—1, 3—cyclopentylene vinylene). The sample is strongly oxidized in air. Under vacuum the activation energy ... -
Electrophoretic patterns of proteins and enzymes in paramphistomum (p.) Microbothrium and carmyerius gregarius
( Qatar University , 1990 , Article)The electrophoretic patterns of total soluble proteins, esterases, Glutamic-oxaloacetate transaminase (GOT) and malate dehydrogenase (MDH) are determined in two paramphistomes, infecting cows and buffaloes, namely ... -
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 ... -
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 ... -
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 ... -
Flavonoids From Cressa Cretica
( Qatar University , 2005 , Article)The aerial parts of Cressa cretica L. yielded five flavonoids that were identified as quercetin (1), quercetin-3-B-O-D-glucoside (2), kaempferol-3-O-B-D-glucoside (3), kaempferol-3-O-a-L-rhamno-(1—+6)- B-D-glucoside (a) ... -
Formation of Usual and Bridging Complexes using organoselenium and -Tellurium compounds
( Qatar University , 2005 , Article)The reactions of l,3-benzoselenadiazole with some diiodo selenium and tellurium heterocyclic compounds have led to the formation of charge transfer complexes. From the same reactions but in the presence of I9PtC14 new types ... -
Gc-ms analysis and antimicrobial activity of volatile oil of Pituranthos tortuosus (desf.)
( Qatar University , 1995 , Article)Volatile oil of Pituranthos tortuosus (Desf.), family Umbelliferae was prepared in yield of (0.5%). GC-MS analysis of the oil resulted in identification of eight components. Dill apiole was the main constituent (94.76%). ... -
Heterocyclic Aminoacrylate Esters Of Potential Biological Activity
( Qatar University , 1985 , Article)This work describes the synthesis of N-substituted piperidyl 2-benzoxazole acrylates (la-d); 2-benzothiazole acrylates (2a-d); 2-furyl acrylates (3a-d) and 2-thiophene acrylates (4a-d). The esters of 3-quinuclidyl (Ie, 2e, ... -
HPLC and MS analyses of lutein-esters from tagetes patula L.
( Qatar University , 1996 , Article)Investigation of the xanthophyll esters of Tagetes patula L. flowers resulted in the isolation and identification of lutein, lutein dimyristate, lutein myristate palmitate, lutein dipalmitate and lutein palmitate stearate. ... -
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 ...
