Qatar University Science Journal - [From 1981 TO 2007]: Recent submissions
Now showing items 661-680 of 770
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Mycoflora And Mycotoxins Of Corned Beef
( Qatar University , 1995 , Article)Sixty species and 5 varieties belonging to 21 genera of fungi were collected from 20 corned beef samples . The average total counts of fungi ranged from 56 -236,47-275 and 39-202 colonies /g on glucose - 10% NAC1 - glucose ... -
Histochemical Studies On argas (Argas) Hermanni (Ixodoidea: Argasidae) Salivary Glands
( Qatar University , 1994 , Article)Basic proteins, tryptophan, tyrosine, free NH2 and SH groups, general carbohydrates, glycogen, acid mucopolysaccharides and lipids were investigated during nymphal and adult Argas (Argas) hermanni Audouin development. In ... -
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 : 4. Growth and mortality of longspine sea bream (argyrops spinifer)
( Qatar University , 1995 , Article)Age, growth and mortality of longspine scabrcam, Argyrops spinifer in the Arabian Gulf waters off Qatar were investigated. The study was conducted on 664 fish obtained from Qatar National Fishing Company. The results ... -
Some Aspects Of Camouflage In Animals
( Qatar University , 1989 , Article)Camouflage is the principal device by which vulnerable animals escape predation. The attention of potential predators can be avoided by protective resemblance -mimicking an inedible object such as a seed or leaf. Concealment ... -
Plant growth, metabolism and adaptation in relation to stress conditions XII. Carbohydrate and acid accumulation in phaseolus vulgaris and zea mays stressed with sodium sulphate
( Qatar University , 1990 , Article)Phaseolus vulgaris and Zea mays seedlings and plants were cultured on quarter-strength Hoagland nutrient medium with or without increasing concentrations of Na^SO^. Sodium sulphate increased the levels of reducing sugars ... -
Effect Of Lead Nitrate On The Liver Of The Developing Chick Embryos
( Qatar University , 1991 , Article)The liver of chick embryos treated with 0.03, 0.05 and 0.1 mg lead nitrate/egg showed disorganization of hepatic cords, abnormally enlarged blood sinusoids and extensive cell necrosis. The hepatocytes of lead-treated embryos ... -
Air-Borne Fungi Of Wheat Fields In Egypt
( Qatar University , 1983 , Article)The air borne fungi of wheat fields in El-Minya Governorate were studied during the periods January-May 1977 and December 1977-May 1978 using the plating catch method on 1% glucose and 50% sucrose-Czapek's agar. Fifty-two ... -
Paleozoic Igneous Activity In Egypt
( Qatar University , 1989 , Article)Based on available isotopic age data, including a few K/Ar ages obtained by the writer, a geochronological sequence of the main phases of igneous activity in Egypt during the Paleozoic is presented. Five main phases at ... -
Application of optimum offset shallow seismic reflection technique In the area of west el fashn, egypt
( Qatar University , 1996 , Article)A shallow optimum offset reflection survey was performed in El Fashn area. The purpose of this survey was to determine the continuity of the subsurface boundary conditions The optimum offset shallow seismic reflection ... -
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 ... -
The effect of doping crystals of tgs with some di- and trivalent ions on its: (i) dielectric constant and a.c. Conductivity
( Qatar University , 1987 , Article)The problem of the existence of a new ferroelectric phase transition at low temperatures in TGS crystals is discussed. The influence of some inorganic divalent and trivalent ions presented in the lattice of TGS on dielectric ... -
Geochemistry of biotite and its significance as a guide to the origin of the granitoid rocks of el-imra area, eastern desert, egypt.
( Qatar University , 1988 , Article)Biotites from the granitoid rocks of El-Imra, Eastern Desert, Egypt have been examined. The chemical data of 8 new analyzed biotites are presented. The behaviour of major and trace elements in the examined biotites are ... -
Studies On Bottom Trawling And Demersal Fishes Of Qatar Waters, Arabian Gulf
( Qatar University , 1989 , Article)The bottom trawl fishery and their by-catch from Qatar waters were analysed on a systematic basis for species composition, length, weight and girth-among other things-during the year 1986-1987. The resuls proved a steady ... -
Origin And Tectonic Environment Of The Pan-African Rocks Of Abu El Tiyur Area, Eastern Desert, Egypt
( Qatar University , 1995 , Article)The present paper deals with the geochemistry and origin of the Pan - African basement rocks, which covers about 825 km2 North of Abu El Tiyur area, in the Central Eastern Desert of Egypt. The petrochemical character of ... -
On Using the One-Exposure Method for Stress Measurements by X-Rays in Technology and Scientific Research
( Qatar University , 1982 , Article)The paper discusses the connection between macroscopic internal stresses and the technological character of technical materials. The basic theoretical relations which are used with X-Ray tensiometry of macroscopic internal ... -
Synthesis and Spectroscopic Studies ofAtenolol Derivatives with Enhanced Lipophilicity as Potential Prodrugs
( Qatar University , 2002 , Article)Atenolol, a selective pi-adrenoceptor blocking agent is characterized by its low bioavailability. A number of atenolol prodrugs were synthesized to improve its lipid solubility and hence bioavailability. These compounds ... -
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 ... -
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 ... -
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 ...