Qatar University Science Journal - [From 1981 TO 2007]: المرسلات الحديثة
السجلات المعروضة 321 -- 340 من 770
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Pan African magmatism in the Zabara District, Central Eastern Desert, Egypt: Geochemistry and Petrogenesis
( Qatar University , 1997 , Article)The rocks of the Zabara district include ophiolitic and non-ophiolitic sequences. The ophiolitic ones are metagabbro and metabasalt associated with metasediments, whereas the non -ophiolitic sequence includes intermediate ... -
Effect Of Unfed Female Weight On The Biology Of Hyalomma (Hyalomma) Impeltatum Schulze and Schlottke (Acari: Ixodidae)
( Qatar University , 1989 , Article)Unfed female Hyalomma (Hyalomma) impeltatum Schuize and Schlottke in 4 different weight groups of 2.6-5.0, 6.2-10.0, 10.3-14.7 and 15.2-22.3 mg, respectively, were investigated for the effect of unfed female weight (UFW) ... -
Ultrastructural Study Of Type "B" Neurosecretory Cells In The Earthworm Nervous System
( Qatar University , 1991 , Article)Neurosecretory cell types Bi—B5 are widely distributed throughout the cerebral, subesophageal, nerve cord and peripheral ganglia of the oligochaete Aporrectodea caliginosa, Lumbricus terrestris, Eisenia foetida, Octolasion ... -
Azo-Hydrazo Tautomerism: Further Evidence Based On Polarographic Reduction And Acidity Function Of Some Heterocyclic Compounds Containing Oximino-Group
( Qatar University , 1994 , Article)Potentiometric pKa and polarographic behaviour of l,3-indandione-monoxime-2-phenyl azo and four of its substituted derivatives were investigated in buffer solution of pH -2-12. The results showed that the compounds are in ... -
The Appendicular Skeleton In The Hatching And In Young Bunopus Tuberculatus Blanford, 1874 (Gekkonidae, Reptilia)
( Qatar University , 1988 , Article)The appendicular skeleton and its calcification are described in Bunopus tuberculatus at 3 ages: at hatching, 6-month-old and 12-month-old. Between the 3 ages there are several differences in the osteological pattern. The ... -
Electron microscopic and autoradiographic analysis of the distribution of the vagus nerve in the ferret stomach
( Qatar University , 1999 , Article)In this study, tritiated leucine was injected into the vagal dorsal motor nucleus after acute and chronic partial vagotomy. The method of sampling of the stomach, application of % 2 test and the analysis of the electron ... -
Lead-Induced Malformations and Kidney Destruction of Developing Chick Embryos
( Qatar University , 1993 , Article)Two doses of lead nitrate, 0.5 and 0.1 mg/egg, were injected into the eggs after 3 days of indubation. Lead nitrate increased mortality rate and decreased the body weight of developing embryos. The lead nitrate also decreased ... -
Plant growth, metabolism and adaptation in relation to stress conditions. Vi. Differential effects of sodium sulphate on growth and element content of phaseolus vulgaris and zea mays
( Qatar University , 1989 , Article)Seeds of Phaseolus and Zea were germinated and then cultured either in Hoagland nutrient solution (1/4-strength) by itself or in combination with different concentrations of Na^SC^. Salinization induced, in general, varied ... -
Two Notes On Modular P-Algebras
( Qatar University , 1988 , Article)According to the definition of congruence .pairs which is given by T. Katrinak, every congruence relation of a modular p-algebra can be uniquely determined by a congruence pair. In the present paper, we characterize strong ... -
Application Of Different Methods For The Preparation Of Chlorophyll Pigments For Food And Pharmaceutical Industries
( Qatar University , 1994 , Article)The main objective of this work is to establish an economic and applied technique for the production of chlorophyll pigments and their derivatives namely Cu-chlorophyll complex in the form of colour additives. These trials ... -
Histomorphology Of The Skin Of The Gecko Cyrtodactylus Scaber (Gekkonidae, Reptilia)
( Qatar University , 1989 , Article)The histological structures from different dorsal and ventral regions of the skin of the gecko Cyrtodactylus scaber are described. Qualitative differences in the skin structures are recorded. The correlation between the ... -
The effect of doping crystals of tgs with some di- and trivalent ions on its: (ii) polarization and piezoelectricity
( Qatar University , 1987 , Article)The polarization, coercive field,piezoelectricity and electromechanical coupling for pure and doped single crystals of TGS arp investigated in the temperature range 77-325 K. The influence of the divalent ions Ni 2+, Cu2 ... -
Meiofaunal Life of Man-Made Wastewater Ponds in Qatar
( Qatar University , 2002 , Article)The meiofaunal life of two wastewater ponds around Doha City was studied for the period October 2000-October 2001. The substrate nature of the two ponds was found to be similar in mean particle sizes but the densities of ... -
Scanning electron microscopy of the egg-shell of the fly synthesiomyia Nudiseta (wulp)
( Qatar University , 1994 , Article)The ultrastructure of the egg-shell of the fly Synthesiomyia nudiseta has been studied by scanning electron microscopy. The surface of the outer chorion is highly ridged, grooved and has a reticulate appearance except at ... -
Effect Of Gossypol, Apogossypol And Gossypolone On Fertility Of Male Rats And In Vitro Sperm Motility
( Qatar University , 1993 , Article)The effect of the naturally occurring polyphenolic pigment, gossypol, and some of its metabolites, apogossypol and gossypolone, on the fertility of male rats has been studied in vivo. The normal growth of the rats was ... -
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 ... -
Petrophysical Studies For Some Lower Cretaceous Formations, Western Desert, Egypt
( Qatar University , 1988 , Article)The Kharita, the Dahab and the Alamein Formations are representing the upper part of the Lower Cretaceous rock sequence in the northern part of the Egyptain Western Desert. Some core samples have been obtained from these ... -
Geochemistry and Petrogenesis of a Late Proterozoic Volcanic Sequence in the Magal Gebriel Area, South Eastern Desert, Egypt
( Qatar University , 2000 , Article)Metabasalts and meta-andesites together with small amounts of metadacite constitute the Magal Gebriel volanic suite. Restricted amounts of unmetamorphosed rhyolitic rocks are also present. The metavolcanics show a wide ... -
The Status Of Qatar's Fisheries During 1980-1990
( Qatar University , 1992 , Article)The present study was conducted to overview the status of Qatar's fisheries during 1980-1990, using the fishery statistics data. issued annually by the Department of Fisheries, Ministry of Municipal Affairs & Agriculture, ... -
Combined effects of oxygen, partial vacuum, temperature, humidity and gamma radiation on mating competitiveness of culex pipiens complex l. Males
( Qatar University , 1993 , Article)When the pupal stage of Culex pipiens complex L. male mosquito was exposed to gamma radiation (60 Gy), oxygen, partial vacuum (0.1 torr), low temperature (10°C), for one or two hours, or low humidity (31% R. H.) for 3 ...