Browsing Qatar University Science Journal - [From 1981 TO 2007] by Title
Now showing items 660-679 of 770
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Stable isotopic composition, stoicometry and origin of Siliceous dolomite of naqb siwa member Bahariya oasis, Egypt
( Qatar University , 1994 , Article)The Lower Campanian Naqb Siwa member exposed near Bahariya Oasis, Egypt, is a shoal ing-upward dolomite sequence that hosts chert nodules and lenses and cavity fillings of quartz and calcite. Dolomite is dominantly replacive, ... -
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, ... -
Stereochemistry of some high coordination compounds of dioxouranium(VI) With thiosemicarbazones
( Qatar University , 1994 , Article)The UO2 ion is peculiar in its coordination behaviour, because of its inherent capacity of forming compounds with higher coordination number. In the present work we describe the synthesis of a series of eight, nine and ten ... -
Stochastic Classes Of Life Distributions
( Qatar University , 1990 , Article)The concept of stochastic ordering of random variables is used to characterize the behaviour of the life length variables. This leads to some new classes of ageing namely, the stochastic classes of life distributions. The ... -
Strain Broadening of E.P.R. Linewidths in Fe/Mgo Single Crystals and Powders
( Qatar University , 2004 , Article)The E.P.R. linewidth of the M= + 1/2 <-» -1/2 transition of Fe3+ spectrum of Fe/MgO single crystals and powders have been measured at 9 GHz before and after annealing. The nominal iron concentrations ranged from 310 to ... -
Stratigraphy and paleobathymetry of upper cretaceous-lower tertiary exposures in beris-doush area, kharga oasis, western desert, Egypt.
( Qatar University , 1990 , Article)The detailed study of the Upper Cretaceous-Lower Tertiary succession exposed in Beris-Doush area enabled the subdivision of this succession into a number of rock units well known in the Nile Valley facies area in Egypt. ... -
Stratigraphy And Petrology Of The Eocene Rocks At Maghagha (East And West), Nile Valley, Egypt
( Qatar University , 1985 , Article)Combined paleontological and petrological studies on the Eocene rocks at Maghagha revealed that the succession belongs to one biostratigraphic zone; the Numrnulites gizehensis gizehensis zone. Nummulites striatus was ... -
Strong and Weak n-Homogeneous Spaces
( Qatar University , 2004 , Article)In this paper we introduce new types of n-homogeneity, we call them n-homogeneous of type 2 and type 3, denoted by nH2, nH3 respectively. We show that every 3H3-space is bihomogeneous space. Also, every finite nH3-space ... -
Structural Elements And Formation Parameters For Some Lower Cretaceous Sequences In The Western Desert, Egypt
( Qatar University , 1987 , Article)The Lower Cretaceous sequences in the northern part of the Western Desert has been penetrated by many of drilled bore—holes adopted by different oil companies. It was encountered at depths ranging from 1200 to 3500 m. The ... -
The structure of tetraketones in the solid state: the crystal structure of 1,6- Diphenylhexane-1,3,4,6-tetrone
( Qatar University , 1994 , Article)The crystal structure of l,6-diphenylhexane-l,3,4,6-tetrone was determined, CjgHi4O4, M 294.31 monoclinic, space group P2j/n (# 14), a 5.1192 (6) A, b 9.085 (9) A, c 15.366 (4) A, b 97.91 (4)°, p (calc) 1.362 g/cm3, Z 2, ... -
The Structures And Mode Of Formation Of Some Cyclodiphosphazane Derivatives With Urea And Thiourea
( Qatar University , 1986 , Article)The methods of preparation and possible reaction mechanisms for the formation of some geminal and nongeminal aminocyclodiphosph (v) azanes of the type (II - V) are discussed. These cyclodiphosphazanes obtained from the ... -
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 ... -
Studies for determining antimicrobial activity of solenostemma argel (del) hayne. 2-extraction with chloroform/methanol in different proportions
( Qatar University , 1994 , Article)Aerial parts of Solenostemma argel plant were successively extracted with chloroform/methanol in different proportions (4 fractions). The phytochemical and chromatographic screening as well as quantitative determination ... -
Studies in bidirectional movement in vicia faba l.
( Qatar University , 1984 , Article)Surgery was used to investigate bidirectional movement in a single vascular bundle of Vicia faba L. In one experiment it was found that radiocarbon had moved upwards and downwards via one isolated bundle when leaf one and ... -
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 ... -
Studies On Catch Rates Of Bottom Trawlers In Qatar Waters, Arabian Gulf
( Qatar University , 1990 , Article)Data pertaining to catch, effort, time, space, landing, commercial value, by-catch and some environmental parameters covering the period from 1983 to 1988 were used in this regard. The results conformed that; the CPUE ... -
Studies on digenetic trematodes of some red sea fish 1. General survey
( Qatar University , 1983 , Article)812 Red Sea fish, belonging to 33 species, were examined for digenetic trematodes. All species of fish were infected with one or more genera of trematodes. Out of 812 fish, 394 (48.5%) were positive. The incidence of ... -
Studies on growth and chemical composition of tobacco varieties. IV - comparative effects of various combinations of fertilizers on economic potentialities of tobacco plants
( Qatar University , 1987 , Article)In two experiments, tobacco plants were treated with various combinations of ammonium nitrate (23% N) and compound C (3.5% N, 23% P and 16% K). At all levels used in experiment I, stem length and number of leaves were ... -
Studies On Plant Growth Regulators And Enzymes Production By Some Bacteria
( Qatar University , 1994 , Article)Twenty four bacterial strains of thallobacteria belonging to genus Streptomyces were tested for their potentialities to produce plant growth regulators and some hydrolases in shake cultures. Seven strains namely; Streptomyces ... -
Studies On Possible Factors In Saliva In The Etiology Of Oral Cancer
( Qatar University , 1994 , Article)The present study was performed on 195 individuals divided according to their oral hygiene into the following four groups; Group I: Control healthy individuals; Group II: Patients suffering of early to moderate periodontitis; ...