Qatar University Science Journal - [From 1981 TO 2007]: Recent submissions
Now showing items 121-140 of 770
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The blood cells of a sea urchin from abou-kir coast Alexandria, Egypt.
( Qatar University , 1993 , Article)The blood cells of a common sea urchin, collected from Abou-Kir region, were investigated using light and electron microscopy. Their distribution, properties, characteristics and histogenesis were determined. On the basis ... -
Hepatitis-B Markers In Sera Of Egyptian Hepatoma Patients
( Qatar University , 1994 , Article)The present study was performed on 52 hepatoma patients; 46 of them were of the histopathological type known as hepatic cell carcinoma (HCC), aiming to investigate the possible role of hepatitis B viral (HBV) infection in ... -
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 ... -
On Two New Haemogregarines (Protozoa: Apicomplexa) From Colubrid And Elapidae Snakes In Egypt
( Qatar University , 1996 , Article)Two species of colubrid and elapid snakes collected from different localities in Egypt were examined for protozoan blood parasites. TWo new species of Haemogregarina senso lato are described: Haemogregarina garnhami n.sp. ... -
New Potassium/Argon Ages For The Volcanic Rocks Of Halul Island (Qatar)
( Qatar University , 1988 , Article)The only rocks of igneous origin known to be exposed in Qatar are those of Halul and Shra'Auh Islands. They occur within a salt diapir and the age of these rocks is uncertain. They have generally been assigned to the Hormuz ... -
The effect of two substituents on different organoselenides and tellurides to form new charge-transfer complexes
( Qatar University , 2004 , 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 ... -
Calculation Of Mass Yield Distributions In Fission Induced By High Energy Protons
( Qatar University , 1991 , Article)An analytical expression is obtained for the mass-yield distribution in fission induced by high-energy protons, using a two-step model. In the first step, the incident proton penetrates the target nucleus, knocking out ... -
A Special System Of Boundary Value Problems
( Qatar University , 1987 , Article)In this paper we introduce a special system of boundary value problems and give a method for solving it. Then we give a detailed application of this method to a system of boundary value problems of Hilbert type. -
The Reproducing Capacity of Gamma Irradiated Adults of Trogoderma Versicolor (Creutz)
( Qatar University , 1993 , Article)Male and female, Trogoderma versicolor (Creutz.) were irradiated by gamma radiation as newly emerged adults (12-24 hrs. after emergence). Males required higher doses than females to be sterilized and the reproductive ... -
Improvement Of The Piecewise Approximation Methods
( Qatar University , 1996 , Article)A piecewise approximation method is described for planar curves. The order of classical piecewise approximations is improved. The method exploits the freedom in the choice of the parametrization and rises the approximation ... -
On 2n+L-Vertex-Free Graphs
( Qatar University , 1983 , Article)We shall introduce the concepts of pseudoadjacent, pseudocoatraction and pseudoho-momorphism. We shall show, with the help of these concepts, in theorem 2 that every quadrilateral graph V (which is a 4-vertexgraph) has ... -
Separation and preconcentration of malathion and azamethiphos by Unloaded polyurethane foams
( Qatar University , 1994 , Article)The feasibility of using unloaded polyether type polyurethahe foams for the extraction and separation of malathion and azamethiphos in batch and column operations has been examined. The effects of pH, ionic strength, shaking ... -
A New Tetrafluoroborate Liquid Membrane Electrode For Selective Determination Of Boron
( Qatar University , 1986 , Article)The construction and performance characteristics of a new liquid membrane electrode selective for BF^ion are herein described. The electrode incorporates nitron-tetrafluoroborate ion pair complex in nitrobenzene as a liquid ... -
Indecomposable Representations Of Order Of E6
( Qatar University , 1985 , Article)The extended Dynkin diagram is a valued graph. We are going to construct a Baechstrom order A associateed to Eg. We prove, by constructions, that the order A of infinite lattice-type but can be listed (tame-type), i.e., ... -
Stable isotopic composition, stoicometry and origin of Siliceous dolomite of naqb siwa member Bahariya oasis, Egypt
( Qatar University , 1994 , Article)The Lower Campanian Naqb Siwa member exposed near Bahariya Oasis, Egypt, is a shoal ing-upward dolomite sequence that hosts chert nodules and lenses and cavity fillings of quartz and calcite. Dolomite is dominantly replacive, ... -
On Some Shrinkage Techniques For Estimating The Parameters Of Exponential Distribution
( Qatar University , 1986 , Article)A variety of shrinkage methods have been proposed for estimation of some unknown parameter by considering estimators based on a prior guess of the value of the parameter. We compare some of the shrunken estimators for the ... -
Possible Ionic Effects of NaCl on Two Mexican Wheat Cultivars
( Qatar University , 2005 , Article)The effect of NaCl on growth and physiology of two Mexican wheat (Triticum asestivum L) cultivars (Cajeme: salt tolerant, and Yecora: salt sensitive) was compared with that of other osmotic agents, Na2SOa (ionic compound) ... -
Chromite Enrichment in the Recent Fluviatile Sediments, North Iraq
( Qatar University , 1999 , Article)The Recent sediments from North Iraq are characterized by a higher content of chromite. This paper deals with the mineralogy and geochemistry of chromite in the heavy mineral assemblages from Recent fluvial sediments in ... -
Glaciations In The Arabian Peninsula
( Qatar University , 1990 , Article)Glaciations affected the Arabian Peninsula three times. This was during the Late Ordovician, the Late Carboniferous-Early Permian, and the Pleistocene. Recorded evidence of Paleozoic glaciations in Arabia, includes tillites, ... -
Prediction Intervals For Future Sample Mean From Inverse Gaussian Distribution
( Qatar University , 1991 , Article)A random sample Xi, Xz, ..., Xn from Inverse Gaussian distribution I(/x,X) is observed. On the basis of this observed sample a lOOp prediction interval of the mean Y of a future sample Yi, ..., Ym from I(^,^.) has been ...
