Qatar University Science Journal - [From 1981 TO 2007]: Recent submissions
Now showing items 181-200 of 770
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Ultrastructural localization of acid and alkaline Phosphatases, glucose-6-phosphatase and odium-potassium Atpase enzymes in the neurosecretory and oesophageal Cells of earthworm
( Qatar University , 1994 , Article)In the present study we have localized acid and alkaline phosphatases, glucose-6-phosphatase and sodium-potassium ATPase (Na-K-ATPase) in ultra-thin sections of cerebral neurosecretory cells and oesophageal cells of the ... -
On Symboloic Reasoning and Direct Inference Principle
( Qatar University , 2004 , Article)This paper discusses an approach using the M-valued symbolic logic with syllogistic reasoning and direct inference principle (reasoning from statistical information to conclusions about individuals), to manipu¬late statistical ... -
Proline Accumulation In Plants Of Different Ecological Groups As A Response To Water Deficit
( Qatar University , 1985 , Article)The diurnal changes in proline content were investigated in different plants including a desert shrub (Retama raetam), a halophytic grass (Spombolus virgimcus) and a cultivated crop (Zea mays). Though these species have ... -
The Possible Effects of Some Mineral Nutrients and Industrial Chemical Effuents on Wild Plants in Central Sudan
( Qatar University , 2006 , Article)The effects of some mineral nutrients and industrial chemical effluents from a textile factory and tanning activities on the growth and distribution of Typha angustata, Cyperus laevigatus. Paspalum viginatum, Cassia senna ... -
Ecology and biodiversity profile of the Genus Streptomyces in the soil of the State of Qatar
( Qatar University , 2007 , Article)Ecology and biodiversity profile of Streptomyces in the soil of Qatar have been studied in 123 soil samples from different sites distributed all over the country. Moisture contents of soils samples ranged between 0.2-8.8% ... -
Approximate Solution For A Problem Of Propagation Of Elastic-Plastic Wave In The Half-Space
( Qatar University , 1984 , Article)In this paper, we consider a half-space occupying an elastic-plastic medium. Treatments were carried out under the assumption of perpendicular load, on boundary which propagates with a constant speed D. The assumption ... -
New Contributions To The Geology, Geochemistry And Tectonic Setting Of The Aswan Granites, Southern Egypt
( Qatar University , 1990 , Article)The Aswan granitic rocks occupy a region in southern Egypt between the stable Archaean craton of the south Western Desert and the less stable Pan-African belt of the south Eastern Desert. They include light-grey medium ... -
Phytoplankton In An Area Of Multi-Polluting Factors West Of Alexandria, Egypt
( Qatar University , 1987 , Article)A year cycle of phytoplankton community in polluted inshore area of the Egyptian Mediterranean water, west of Alexandria, was followed. Seasonal and regional variations of the physico-chemical characteristics were studied ... -
Lithofacies and depositional environments Of the lower jurassic sediments In central Saudi Arabia
( Qatar University , 1999 , Article)The lithofacies, microfacies and sedimentary environments of the surface Lower. Jurassic sediments in central Saudi Arabia are studied. The Lower Jurassic is represented by the marine clastic Marrat Frormation which is ... -
Whole-rock powders and their analysis by an electron mocroprobe technique
( Qatar University , 2001 , Article)Basic rock powders finder than 100 mesh were fushed in a molybdenum and tungsten boat in nitrogen atmosphere. The fusion technique uses very small amounts of sample which is suitable for rapid analysisof rock sample, ... -
On an inverse scattering problem with a discontinuous coefficient On the whole line
( Qatar University , 1994 , Article)This paper is devoted to study the inverse scattering problem of a generalized Sturm-Liouville equation on the whole line.The solutions of the considered problem and their asymptotic behaviour are presented.The expansion ... -
Helminth parasites of fishes from the arabian gulf 2 . the digenetic trematode genera Hamacreadium linton, 1910 and cainocreadium Nicoll, 1909
( Qatar University , 1986 , Article)The status of the related digenetic trematode genera Hamacreadium Linton 1910 and Cainocreadium Nicoll, 1909 is briefly reviewed. Hamacreadium Linton 1910 is described from Lutjanus fulviflamma and L. russelli. Cainocreadium ... -
Helminth parasites of fishes from the arabian gulf: 5. On helicometrina qatarensis n. Sp. (digenea: opecoelidae) and stephanostomum nagatyi N. SP. (digenea: acanthocolpidae); parasites of Epinephelus Spp. from Qatari Waters
( Qatar University , 1988 , Article)Helicometrina qatarensis n. sp. is described from Epinephelus tauvina and E. summana. It differs from other species of Helicometrina which have 9 testes in the body shape, position of genital pore, distribution of vitellaria ... -
On Three Species Of The Trematode Genus Plagioporus Stafford, 1904 From Red Sea Fishes
( Qatar University , 1985 , Article)The genus PIagioporus is breiefly reviewed. P. (Caudotestis) neopercis is re-described from Anampses caeruleopunctatus and Lethrinus miniatus and P. (Caudotestis) lethrini from L. nebulosus and L. miniatus. Both trematodes ... -
Studies On Possible Factors In Saliva In The Etiology Of Oral Cancer
( Qatar University , 1994 , Article)The present study was performed on 195 individuals divided according to their oral hygiene into the following four groups; Group I: Control healthy individuals; Group II: Patients suffering of early to moderate periodontitis; ... -
Z1, center orientations and adsorption of atomic halogens at the (001) surfaces of Alkaili Chloride Crystals: DFT Calculations.
( Qatar University , 2004 , Article)An attempt has been made to examine the relative stabilities of Z, center orientations at the surfaces of Be2+, Mg2+ and Ca2+ doped LiCl, NaCl and KC1 ionic crystals as well as the effects of Z, center on the adsorption ... -
Plant diversity, dispersion, community similarity and vegetation description in united arab emirates. I. North western area
( Qatar University , 1995 , Article)Papers presented at The gulf symposium on Environmental biology, University of Qatar, 7-9 May 1994 *********** Plant population patterns in six natural communities (A-F) in the northern part of the UAE were studied. The ... -
The effect of the insecticide (primicid) On neurosecretory cells of the earthworm aporrectodea caliginosa
( Qatar University , 1995 , Article)The effect of the insecticide "Primicid" on the neurosecretory cells of the cerebral ganglion of the earthworm Aporrectodea caliginosa was studied. The fine changes in the organelles of certain ncurosecrelory cells was ... -
Paragorgorhynchus aswanensis n.sp. (acanthocephala: Echinorhychidae): an intestinal parasite of some fishes from aswan high dam lake in upper egypt
( Qatar University , 1990 , Article)Paragorgorhynchus aswanensis n.sp. is described, both by light and scanning electron microscopy, from Lates niloticus,, Clarias lazera, Bagrus bayad, B. docmac, and Tetraodon fahaka, caught from the Aswan High Dam Lake in ... -
Correlations of partition data of carboxylic acids in water/organic solvent Systems with solvatochromic parameters
( Qatar University , 1994 , Article)The partition coefficients of C2-Cg carboxylic acid monomeric forms between water and various organic solvents as well as the dimerization constants have been shown to be well correlated in terms of the solvatochromic ...