Qatar University Science Journal - [From 1981 TO 2007]: المرسلات الحديثة
السجلات المعروضة 81 -- 100 من 770
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Experimental Investigation of the N-Pbs/P-Si Heterojunction Band Lineup with I-V and C-V Measurements
( Qatar University , 2005 , Article)In this paper we present experimental investigation of band lineup of near ideal PbS/Si heterojunction diode using I-V and C-V measurements. The C-V measurements show that the fabricated diodes were abrupt type, and the ... -
Plant diversity, dispersion, community similarity, and vegetation description in united arab emirates. II eastern coast
( Qatar University , 1995 , Article)Papers presented at The gulf symposium on Environmental biology, University of Qatar, 7-9 May 1994 *********** The vegetation on the eastern coast of UAE was studied in 3 undisturbed sites. Dispersion, species-area, and ... -
Forecasting Of The Storm Surge In Winter At Alexandria (Egypt)
( Qatar University , 1992 , Article)Since storms frequently occur in the winter season, at Alexandria, SE of the Mediterranean Sea. storm surges often affect this area. In this paper, we attempt to forecast the storm surge heights in the commercial Western ... -
Gamma Irradiation of 4th Instar Larva of Angoumois Grain Moth and Effects on Parent and Their Generations
( Qatar University , 2006 , Article)Late fourth stage larvae of Angomous grain moth, Sitotroga cerealella (Olivier) were gamma irradiated with doses 0 ( control), 25, 50 75, 100, 125 and 150 Gy. The moths originated from larvae irradiated with 150 Gy became ... -
Regeneration of the vagus nerve after highly selective vagotomy, an autoradiographic study in the ferret stomach .
( Qatar University , 1995 , Article)This study investigates the regeneration of the vagal nerve fibres after highly selective vagotomy in the ferret stomach by using the autoradiographic technique. Autoradiographic examination of the body of the stomach in ... -
Abundance Of Insects And Mites Infesting Stored Grain And Animal Feed In Riyadh And Dammam Provinces, Saudi Arabia
( Qatar University , 1994 , Article)Insects and mites infesting wheat, maize and wheat bran, stored in plants at Riyadh and Dammam, Saudi Arabia, were scanned in 2 seasons, 1987 and 1988. Grains from the local markets and dust from both provinces were also ... -
Mechanism Of The Inhibition Afforded By Some Hydrazone Oxime Derivatives Towards Aluminium In 2m Naoh Solution
( Qatar University , 1991 , Article)The effect of some hydrazone oxime derivatives on the corrosion of aluminium in 2M NaOH solution was studied by polarization and weight-loss techniques. Polarization data indicated that all inhibitors tested were of a mixed ... -
Effect of the insecticide sumicidin on the biology and survival of the american cockroach nymph periplaneta americana l. (blattidae, dictyoptera).
( Qatar University , 1995 , Article)This study was conducted under laboratory conditions to evaluate the effect of sumicidin (a pyrethriod insecticide) on the heart rates, convulsion and mortality of the american coackroach nymph Periplaneta americana L., a ... -
Histological And Histochemical Studies On The Decidua And The Uterine Glands During Early Pregnancy In The Rat (Rattus rattus)
( Qatar University , 1986 , Article)Histological and histochemical studies were carried out on the decidua and uterine glands in the uteri of pregnant rats 'Rattusrattus' between 129 hours post.-coitum (p.c) and day nine of pregnancy. Decidualization was ... -
Dehydration of Ethanol over HF-treated Al2 O3 using the GC-column as Chemical Reactor
( Qatar University , 1981 , Article)The effect of treating •y-alumina with hydrofluoric acid on the dehydration reaction of ethanol was investigated at 325°C. The gas chromatographic column was used as a chemical reactor. The rate of formation of ethylene ... -
Ecological and phytochemical studies on the "miswak", salvadora persica l.
( Qatar University , 1984 , Article)The "Miswak", which is produced from the stolons and branches of Salvadora persica is used as a substitute for ordinary tooth brushes. The use of "Miswak" has been recommended by Islam. It is endowed by several characteristics ... -
Studies for determining antimicrobial activity of solenostemma argel (del) hayne. 1-extraction with methanol/water in different proportions
( Qatar University , 1994 , Article)Aerial parts of Solenostemma argel plant were successively extracted with methanol/water in different proportions (4 fractions). The phytochemical and chromatographic screening as well as quantitative determination of the ... -
Completeness Of Distributive P-Algebras
( Qatar University , 1988 , Article)According to the triple characterization of distributive p-algebras which is given by T. Katrinak, we characterize the completeness of distributive p-algebras. -
Biostratigraphy Of The Subsurface Oligocene Sediments In The North Western Desert, Egypt
( Qatar University , 1984 , Article)This paper deals with the study of planktonic foraminifera, larger foraminifera and ostracoda in the Oligocene sediments in four wells: Abu Tunis No. IX, East Faghur-I, Khalda No. I and North Ghazalat No. I, North Western ... -
Translation - invariant Positive-definite Generalized Kernels of Infinite Number of Variables
( Qatar University , 1981 , Article)In the theory of spectral analysis of positive-definite j<.ernels, there exist well-developed methods based on the ideas of Krein connected with the construction of a Hilbert space by means of a kernel [ 1, 11]. In the ... -
Ionic Conductivity and Ionic Jump Distance of Nuclear Detectors Group CR-39 and BM-355
( Qatar University , 2000 , Article)Electric properties of two nuclear detectors (CR-39 and BM-355) have been investigated as a function of temperature differences. The conductivity appears to be ionic and it was increased with the temperature increase for ... -
Total Mercury Distribution In Surface Sediments From The Arabian Gulf
( Qatar University , 1994 , Article)Surface sediment samples collected during the first leg of Mt. Mitchell cruise and covering the entire Gulf, were analysed for their total Hg content. The total Hg concentrations ranged from 0.032 to 0.27 ug/g dry wt. The ... -
Nitrogen Transformations as affected by some factors at cultivated soils in Saudi Arabia
( Qatar University , 2001 , Article)The influence of serial concentration of salts (0.5, 1.0 and 1.5%), application of organic matter (0.5, 1.0 and 1.5% of wheat strat) and varying soil moisture content 50, 70 and 90%) on nitrification in sandy loam soil was ... -
Comparative Study of 11 Honey Samples Sold in Riyadh Saudi Arabia
( Qatar University , 2006 , Article)11 honey various samples commercially available in Saudi Arabia, were subjected to chemical, toxicological and bacteriological tests. The samples were checked for As and CN, presence of pollens, and for bacteria contamination. ... -
A Family Of Nonramified Functions, Defined In Zz<1
( Qatar University , 1983 , Article)In this article a family of nonramified functtions, defined in zz<l, is obtained. It is characterized by an achieved distortion theorem; its Bloch constant and the limit of convexity are determined. Peschl's principle is. ...
