Browsing Qatar University Science Journal - [From 1981 TO 2007] by Title
Now showing items 727-746 of 770
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Thermoluminescence And Dielectric Properties Of An X-Ray Irradiated Double Sulphate Crystal
( Qatar University , 1994 , Article)Thermoluminescence measurements and A. C. conductivity o(w) for nonirradiated and x-ray irradiated Potassium Cesium Sulphate, KCSSO4, crystals have been studied. TL reader type Harshaw model 2000 A+B and the impedance meter ... -
Thermoluminescence induced by gamma radiation In LiCsSO4 Ferroelastic crystal doped With different heavy metals
( Qatar University , 1994 , Article)Thermoluminescence (TL) glow curves of lithium cesium sulphate ferroelastic crystals LiCsSO4 doped with 0.5% of Os, Tb, Eu and Tl have been studied in the temperature range from room temperature to 300"C. Three peaks are ... -
Thermometric Study of Inhibition of Aluminium Corrosion in Hydrochloric Acid Solution
( Qatar University , 1997 , Article)The use of 6- amino - 4- (4-phenyl)-l,4- dihydro -3- methylpyrano [2,3- c] pyrazole -5- carbonitrile and some related compounds as corrosion inhibitors for aluminium in 2 M HCl solution was studied by the thermometric ... -
Threshold Modelling Of Ship's Dynamics
( Qatar University , 1995 , Article)In this paper we consider an application of a system called threshold system in the field of marine engineering. Properties of this system are discussed and the idea of the impulse response function of threshold system is ... -
The Tidal Range And The Observed Sea Level Variations At Alexandria Harbour
( Qatar University , 1994 , Article)On the basis of sea level observations of five years period (1975-1979), the basic properties of the tidal range at Alexandria are described. The problem of the combined effect of tides and meteorological factors on sea ... -
Time And Order Of Appearance Of Ossification Centres Of The Rat Skeleton
( Qatar University , 1985 , Article)The time and sequence of ossification pattern of the skeletal system of the Rattus rattus were studied in serial whole mounts prepared from Day 10 to Day 21.5 (day of delivery). In the neurocranium, each bone is represent ... -
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 ... -
Total Mercury Levels In The Coastal Environment Of Qatar (Arabian Gulf)
( Qatar University , 1999 , Article)The levels of total Mercury (t-Hg) were determined in various segments of the marine environment of Qatar. Several coastal stations, both on the East as well as the West coast of Qatar were worked for t-Hg in seawater, ... -
Towards a prospective transplantation of the local mangrove avicennia marina (forssk.) Vierh. Growing on coast of qatar i. Ecophysiological performance of juveniles.
( Qatar University , 1990 , Article)A population sample of propagules was collected at random from average size A. marina trees growing at "Dhakhira" (Qatar). This sample was then divided into subsamples which were used to detect the effects of light intensity, ... -
Toxic Effect Of Lannate On Cellular Defence System In Erythrocyte Of Rat
( Qatar University , 1996 , Article)Lannate 1 - methomyl was incubated with erythrocytes of rats at different concentrations. It has been observed that there was a decrease in the activities of superoxide dismutase and glutathione reductase after 1/2 and 16 ... -
Toxicity of Cobalt and Nickel to Fusarium Solani Isolated From Saudi Arabian Soil
( Qatar University , 1994 , Article)Fusarium solani isolated from Saudi Arabian soil was able to grow on liquid media containing up to 300 ug/ml cobalt or nickel. F. solani was tolerant to cobalt than nickel. The results provide evidence of the accumulation ... -
Trace Metals In Qatari Fish And Shellfish
( Qatar University , 1991 , Article)Fish, prawns and crabs purchased at the retail market in Doha, were analysed for cadmium, chromium, copper, lead and zinc. The results indicated significantly elevated concentrations of cadmium in the flesh of the Qatari ... -
Trace Metals in Wastewater Ponds in Qatar
( Qatar University , 2002 , Article)A one-year monitoring program was conducted to determine the extent of metal contamination in two wastewater ponds in Qatar. Abu-Hamour pond receives untreated domestic and industrial waste while Abu-NakhIa pond receives ... -
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 ... -
Transmetalation Mechanisms
( Qatar University , 1993 , Article)Transmetalation is the stoichiometric replacement of the metals in a polymetallic target T with different metals from reagents called transmetalators, TM. Transmetalation at useful rates under mild conditions is an excellent ... -
Treptodemus Latus and chauhnotrema spiniacetabulum (tirematoda: digenea); Hemirhamphidae, parasites of the fish, hemirhamphus marginatus from Qatari waters
( Qatar University , 2000 , Article)The fish Hemiramphus marginatus recently examined from Qatari waters was found to be infected with two species of degenetic trematodes: Treptodemus latus Manter, 1961 and Chauhanotrema spiniacetabulum Nahhas ans Sey, 1998. ... -
Triaryl And Trialkyl Phosphites As Corrosion Inhibitors For Copper In Nitric Acid
( Qatar University , 1992 , Article)Some triaryl and trialkyi phosphites were investigated as inhibitors of the corrosion of copper in nitric acid. The values of inhibitor efficiency from weight-loss measurements are in good agreement with those obtained ... -
Two Forms Of The Backlund Transformation Of A Third Order Differential Equation
( Qatar University , 1996 , Article)Two explicit forms of Backlund transformation of third order dispersive differential equation are derived. The method of derivation depends on the use of a transformation that couples the equation with its modified one. -
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 ... -
A Two-Point Boundary Value Problem for a Second Order Differential Equation with Parameter
( Qatar University , 1982 , Article)
