تصفح Qatar University Science Journal - [From 1981 TO 2007] حسب العنوان
السجلات المعروضة 572 -- 591 من 770
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Progress Of Ocean Sciences In India
( Qatar University , 1999 , Article) -
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 ... -
Proteins of cottonseed (gossypium barbadense) .• extraction and characterization by electrophoresis
( Qatar University , 1995 , Article)The seed proteins of cotton (Gossypium barbadense) were quantitavely and qualitavely investigated. The qualitative study was carried out using different electrophoretic techniques ((PAGE, SDS-PAGE, Poro-PAGE, SDS-Poro-PAGE, ... -
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 ... -
Pullulan production from sugar beat molasses
( Qatar University , 1997 , Article)Sugar beet molasses was used as the substrate for the production of pullulan with Aureobasidum pullulans ATCC 42023. In addition biomass, residual sugar and final pH of the culture medium were investigated. In comparing ... -
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 ... -
Pyrrolizidine alkaloids from heliotropium arbainense and h. Ovalifolium
( Qatar University , 1991 , Article)Investigation of the pyrrolizidine alkaloids of Heliotropium arbainense resulted in the isolation and identification of heliotrine, europine and 7-angelylheliotrine. From H. ovalifolium three alkaloids were isolated: ... -
Pyrrolizidine Alkaloids From Senecio Aegyptius L.
( Qatar University , 1988 , Article)Investigation of the alkaloidal constituents of Senecio aegyptius L. resulted in the isolation and identification of senecionine, dehydrosenkirkine and probably an isomer of seneciphylline. TLC, HPLC and GLC showed the ... -
A Qualitative And Quantitative Survey On The Helminth Parasites Of Fishes From The Aswan High Dam Lake In Egypt
( Qatar University , 1984 , Article)The present investigation is concerned with a helminthological survey of 19 species of fish collected along different seasons from the Aswan High Dam Lake in the southernmost part of Egypt. 615 out of 850 fish (72.4%) are ... -
A Qualitative Approach to Direct Inference Principle
( Qatar University , 2002 , Article)In this paper,we study the suitability of a symbolic model of syllogistic reasoning and direct inference principle with the representation and the management of knowledge based on statistical information and evaluated in ... -
Qualitative Dealing with Quantified Assertions
( Qatar University , 2002 , Article)In this paper we present a newapproach to a symbolic treatment ofquan-tified statements having the following form "Q A's are 5's", knowing that A and B are labels denoting sets,and Q is a linguistic quantifier interpreted ... -
A Random Binary Trees Generation Method
( Qatar University , 2000 , Article)There are two widely used random distributions on binary trees, namely the binary search tree distribution and the uniform distribution. By analyzing the performance of algorithms that manipulate binary trees generated at ... -
A Rational Exponential Model for Unconstrained Non-Linear Optimization
( Qatar University , 2002 , Article)In this Paper, a new algorithm based on the non-quadratic model is suggested for solving unconstrained optimization problems which modifies the classical conjugate gradiant methods. This technique has the same properties ... -
A rational logarithmic model for unconstrained non-linear optimization
( Qatar University , 1997 , Article)A new non-quadratic model is proposed for solving unconstrained optimisation problems which modifies and develops the classical conjugate gradient methods. The technique has the same properties as the classical conjugate ... -
Rayn formation, a new name for the permian khuff formation (S. S.) In saudi arabia
( Qatar University , 1991 , Article)The rank of the Khuff Formation (late Carboniferous-late Permian) in Saudi Arabia is raised to group status and it is divided into Unayzah (late Carboniferous-early Permian) and Rayn (middle-late Permian) Formations. The ... -
Recent Benthic Foraminifera from the Local Water of Qatar, Arabian Gulf
( Qatar University , 2000 , Article)ABSTRACT In the present study, fifty species of Foraminifera are identified from the bottom sediments of the local Qatari waters on the eastern and northern sides of Qatar Peninsula in the Arabian Gulf. These comprise 7 ... -
Record of a fruiticose lichen, Ramalina farinacea (L.) Ach. for Qatar
( Qatar University , 1997 , Article)Lichens are thallophytic lower plants. Ramalina farinacea (L.) Ach., family Ramalinaceae, is the only fruticose lichen recorded in Qatar. It occurs on stony terrain bordering the coastline in association with other more ... -
Records of Marine Interstitial Hymenostomatid Ciliates from the Jubail Marine Wildlife Sanctuary, Saudi Arabia
( Qatar University , 1999 , Article)Sediment samples were collected at low tide from various localities of Jubail Marine Wildlife Sanctuary in the Arabian Gulf during 1996-1997 for the study of the marine interstitial ciliate fauna of the Sanctuary. Eleven ... -
Red cell superoxide dismutase in patients with different liver diseases
( Qatar University , 1995 , Article)Supcroxidc dismutase (SODs, supcroxidc oxidoreductasc, E.C. 1.15.1.1.) activity has been estimated in red blood cells from patients suffering from liver cirrhosis and hcpatoccllular carcinoma. Erythrocytcs supcroxide ... -
Regeneration from different levels along the tail of the geckonid lizard, Bunopus tuberculatus
( Qatar University , 1994 , Article)Study of the influence or amputation level on regenerate length, elongation rate and mitotic index of the tail of the geckonid lizard, Bunopus tuberculatus revealed that the tails amputated such that three-fourth, or ...
