Qatar University Science Journal - [From 1981 TO 2007]: Recent submissions
Now showing items 601-620 of 770
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Aeromagnetic Geophysical Investigation In El-Faiyum District, Western Desert, Egypt
( Qatar University , 1985 , Article)The present paper deals with the interpretation of the aeromagnetic survey executed over the Faiyum area. Western Desert, Egypt. Qualitative as well as quantitative interpretation of the aeromagnetic data were carried out ... -
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 ... -
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 ... -
Irrigation, Planting Date And Intra-Row Spacing Effects On Soybean Grown Under Dry Farming Systems
( Qatar University , 1987 , Article)Two soybean cultivars (Glycine maxima (L) Merr.) differing in maturity period, leaf size and stem height were sown five times at fortnight intervals during the rainy season at four intra—row spacings under supplementary ... -
Phospholipid Fatty Acids Compositions of Sponges from Qatar I- Haplosclerida
( Qatar University , 2006 , Article)The phospholipid fatty acid contents of six Haplosclerida sponges collected along Qatari ;ts, Arabian Gulf, were identified by coupling GC-MS experiments. More than hundred of rated and unsaturated fatty acids have been ... -
An Algorithm for the Consturction of Admissible Tests of the Weibull Distrbution
( Qatar University , 1999 , Article)The method of H. Al-Rawwash and J. Marden [2] is used here for the construction of an admissible test which dominates a given inadmissible one for testing hyupothesis about the Weibull distribution. The algorithm and its ... -
Concentration of Some Heavy Metals in Short Cores in the Nearshore Sediments of Alexandria , Egypt
( Qatar University , 2006 , Article)The Western Harbor, Eastern Harbor and Abu Qir Bay are three sites located along the Alexandria coast. These sites are characterized by extensive maritime and industrial activities. To investigate the penetration of heavy ... -
Phosphate Solubilization in Vitro By Some Soil Yeasts
( Qatar University , 2005 , Article)Soil yeasts including, Candida tropicalis, Geotrichum capitatum, Geotrichum candidum, Rhodotorula minuta and Rhodotorula rubra were isolated from soils of Saudi Arabia. The ability of these soil yeasts to solubilize insoluble ... -
Remarks On S-Closed Spaces
( Qatar University , 1986 , Article)In this paper, several characterizations for s-closed spaces are obtained using regular semiclosed sets and some sets having two properties of near openness and near closedness in the same time. Images of s-closed spaces ... -
Diversity, Habitats and Seasonal Distribution of Fish in Three Protectorates of Southern Sinai on the Red Sea, Egypt
( Qatar University , 2000 , Article)The present investigation is an attempt to study the diversity, habitats and seasonal distribution offish of inshore water at thirteen sites of the three Protectorates (Ras Muhammed, Nabq and Abou Galoum) of Southern Sinai ... -
Design and Performance Evaluation of a High Speed Transport Protocol
( Qatar University , 1994 , Article)Transport protocols that were designed for network today are not adequate for high speed networks of the future due to the increase in network bandwidth relative to the speeds of the processor components. As a result, 100 ... -
Lower Eocene Black Shale Beds Of Rus Formation In North Of Oman-Possible Oil Shales
( Qatar University , 1994 , Article)A suite of samples from some black shale beds of lower Eocene Rus Formation from north of Oman have been investigated through detailed geochemical analyses. The obtained results indicate that these shale beds contain a ... -
Late Maastrichtian And Paleocene Calcareous Nannofossils From Ain Dabadib Section, Nw Kharga Oasis, Egypt
( Qatar University , 1991 , Article)On terms of calcareous nannofossils, the late Maastrichtian and Paleocene sediments were subdivided into several biozones. The Cretaceous-Tertiary boundary is marked by a hiatus concerning the latest Maastrichtian and the ... -
Nomograms For Interpreting Gravity Anomalies Above A Finite Horizontal Cylinder
( Qatar University , 1985 , Article)The present study gives a new method for solving the inverse problem of the gravitational anomalies related to a finite horizontal cylinder, by the use of the downward continuation method. Master curves have been obtained ... -
Amplitude Features Of Fast Compressional Waves In Porous Media For Zero-Offset Synthetic Seismograms
( Qatar University , 1993 , Article)The seismic amplitude are clearly affected by the type of medium through which waves are propagated. A geologic model was designed to study the changes in'amplitudes of the seismic waves within several rocks of different ... -
New switching algorithm for combining new multi-step CG and self-scaling VM algorithms for non-linear optimization
( Qatar University , 1997 , Article)New interleaved CG and self-scaling VM algorithm is presented in this research which combines Al Bayati's self-scaling VM algorithm with another new multi-step CG algorithm with inexact line searches (ILS). In an interleaving ... -
Ecophysiological Characteristics, Distribution, and Nutritional Value of Desert Range Plants in Qatar
( Qatar University , 1993 , Article)Despite the scarcity of water, desert ranges of Qatar can support a characteristic diversity of species and an all-year-round supply of feed. A correlation between carbon dioxide fixation mechanism, distribution of species, ... -
Response of Date Palm Pollen Tube Growth to Storage Period and Conditions
( Qatar University , 1994 , Article)The growth rate of pollen tube of date palm (Pheonix dactylifera L.) pollen grains stored either freeze-dried or unfreeze-dried at 25, 4 and - 8°C was measured after 3,7 and 12 months of storage. The growth of pollen tube ... -
Synthesis And Biological Activity Of Some New 4-(Aminoacyl) Aminopyridines And 2-(Aminoacyl) Aminopyrimidine Derivatives
( Qatar University , 1983 , Article)The synthesis of 4-(N-Tos and N-Pht-aminoacyI) aminopyridines (III - XIV) and 2-(N-Pht-aminoacyl)-aminopyriniidines (XV-XXIV) has been achieved employing the acid chloride and carbodiimide methods. Hydrazinolysis of ... -
Population biology of sparid fishes in Qatari waters 2. Age, growth and mortality of black-banded bream, Mylio bifasciatus (forsskal)
( Qatar University , 1993 , Article)Age, growth and mortality of black-banded bream (faskar) Mylio bifasciatus from the Arabian Gulf waters off Qatar were estimated. The study was conducted on 314 fish obtained from the trawl catch of Qatar National Fishing ...