Qatar University Science Journal - [From 1981 TO 2007]: المرسلات الحديثة
السجلات المعروضة 1 -- 20 من 770
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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). ... -
Occurence of Phytoplankton in Stomach Content and Its Selectivity by Nile Tilapia (Oreochromis niloticus L.) Cultured in Fertilized Earthen Ponds
( Qatar University , 2003 , Article)Nile tilapia (Oreochromis niloticus L.) was cultured in earthen ponds receiving 0, 20, 40, 60 and 100 kg/feddan/month of inorganic fertilizer (20:20:5 N:P:K). The obtained results showed that the composition percentage of ... -
Homomorphisms And Subalgebras Of Ms-Algebras
( Qatar University , 1995 , Article)According to the characterization of MS-algcbras from the subvaricty Kj by mean of the triple construction, we characterize the homomorphisms and the subalgebras of the MS-algcbras. Also, we solve the "Fill-in" problem for ... -
Edaphic properties and soil cyanobacteria of South Western Saudi Arabia.
( Qatar University , 1997 , Article)Three sites at each of five localities, in the South Western Region of Saudi Arabia were surveyed during 1992, for their soil physico-chemical properties, and cyanobacterial communities. The soils were moderately calcareous, ... -
Planting Date Effect On Growth Characters And Yield Of Sorghum Under A Dry Farming-System In An Arabian Gulf Environment
( Qatar University , 1996 , Article)Irrigated crop production in Qatar is a risky enterprise due to extreme weather conditions. Temperature is sufficiently warm to allow planting of grain sorghum [Sorghum bicolor (L.) Moench] from Aug through to Oct. Crops ... -
On The Earthworm Fauna And Distribution In The State Of Qatar
( Qatar University , 1986 , Article)This paper is a preliminary account of the earthworms collected in February and March, 1986, from 10 localities in Qatar. Five species, Amynthas corticis (Family Megascolecidae), Dichogaster bolaui (Family Octochaetidae), ... -
Heat Budget of the Southeastern Part of the Arabian Gulf
( Qatar University , 2001 , Article)The surface heat fluxes through the air-sea interface for the coastal water of the southeastern part of the Arabian Gulf have been estimated using the bulk formulas. The annual mean values of the sensible, latent and back ... -
Chemical Factors Affecting Growth and Development of Lateral Root Formation in Isolated Phaseolus vulgaris L.
( Qatar University , 2007 , Article)The initiation and subsequent emergence of lateral roots as secondary roots have been examined in attached and excised roots of Phaseolus vulgaris grown in the absence or presence of indol-3-yl acetic acid (IAA). Treatments ... -
Proton And Carbon-13 Nuclear Magnetic Resonance Of Some 4-Amino-3-Alkyl (Aryl)-5-Thio-1,2,4-Triazolines And Their Derivatives
( Qatar University , 1991 , Article)The proton and carbon-13 NMR spectra of some 4-amino-3-alkyl(aryl)-5-thio-1,2,4-triazolines, some 3-alkyl-5-thio- 1,2,4-triazolines and some 4-amino-3-aryl-5-thio-l,2,4-triazoles were measured in DMSO-d6 as solvent. The ... -
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 ... -
Screening Of Some Fungi For Uricolytic Activity
( Qatar University , 1996 , Article)Twenty nine species of fungi have been tested for their uricase activity. Only twenty two species of them have the ability to produce uricases. Most of the uncapable fungi to produce uricases belong to Basidiomycotina. ... -
Separation of Two Forms of Extracellular p-glucosidase From a Thermotolerant Aspergillus niveus
( Qatar University , 2003 , Article)Two forms of P-glucosidase ((3-D-glucoside glucohydrolase, EC 3.2.1.21) from the culture filtrate of Aspergillus niveus were separated and partially purified by gel chromatography on Sephadex G-100 column. The two forms ... -
Studies On The Effect Of Cadmium Chloride On The Gonads Of The Developing Chick Embryos
( Qatar University , 1987 , Article)Cadmium chloride was injected in doses of 5, 10, 15 and 20 /xg/egg into the yolk sac of 4—day—old chick embryos. Mortality due to cadmium intaxication increased with dose increase. The mortality rate of chick embryos ... -
Marine Algae As Bioindicators Of Pollution Levels In The Arabian Gulf
( Qatar University , 1995 , Article)The extensive distribution of several marine macroalgal species makes them a potential bioindicator tool for monitoring existing levels of different types of marine pollutants in the region. The present work illustrates ... -
Ascending urinary tract infection in rats caused by Proteus mirabilis
( Qatar University , 1997 , Article)A model for ascending unobstructed urinary tract infection was developed in female rats to study the pathogenesis of urinary tract infection by Proteus mirabilis. Urinary bladders of rats were inoculated by I. V. cannula ... -
Studies On The Decay Of 241Am
( Qatar University , 1989 , Article)The gamma-spectrum of '"Np following the <X -decay of "'Am has been studied using hyper pure Ge-detector and Ge-NaI(Tl) coincidence spectrometer. Some recently reported weak gamma transitions are confirmed, besides two ... -
The Neurosecretory Cells and Neurosecretions in the Developmental Stages of the Cotton Leafworm -Spodoptera Littoralis (B)
( Qatar University , 1981 , Article)In 1955 Nayar described two types of neurosecretory cells in lphita limbata (A- and B-types) [1]. Later, Johannson [2] classified these cells into four categories: A, B, C and D, which he regarded as motor neurones of ... -
Reproducing Formula and Algorithm of a Familv of Biorthonormal Wavelets
( Qatar University , 2005 , Article)In this paper we present a family of biorthonormal wavelets generated by a MRA orthonormal wavelet, which possesses two arbitrary parameters. Then we discuss new expressions of reproducing kernel as well as the corresponding ... -
The Antibiotic Activity Of Some Aquatic Plants And Algal Extracts From Jordan
( Qatar University , 1991 , Article)The antimicrobial activity of the extracts of three fresh water green algae, four marine green algae, two brown marine algae and five red marine algae from the Jordanian part of the Aqaba Gulf, together with four aquatic ... -
Trace Metals In Qatari Fish And Shellfish
( Qatar University , 1991 , Article)Fish, prawns and crabs purchased at the retail market in Doha, were analysed for cadmium, chromium, copper, lead and zinc. The results indicated significantly elevated concentrations of cadmium in the flesh of the Qatari ...