Qatar University Science Journal - [From 1981 TO 2007]: Recent submissions
Now showing items 401-420 of 770
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Some Aspects Of The Autecology Of Panicum Turgidum Forsk
( Qatar University , 1983 , Article)The germination of Panicum turgidum seeds was tested under different conditions. They showed ability to germinate under a range of temperatures from 25-42°C. The maximum percentage of germination was 45%, at 30°C. The ... -
The effects of sea water immersion on the mechanical properties of low density polythylene
( Qatar University , 1997 , Article)The effects of immersion of low-density polyethylene (LDPE) m seawater for times of up to one year were studied using mechanical and ultrasonic techniques. The studies were carried out in the laboratories of the Faculties ... -
Senso-Neuroendocrine Cells Within The Cerebral Ganglion Of The Earthworm Aporrectodea Caliginosa
( Qatar University , 1992 , Article)Ciliated neurones of probable endocrine function are present inside and outside the cerebral ganglion of the earthworm Aporrectodea caliginosa. Cell fibers contain clusters ofsynaptoid vesicles in regions adjacent to the ... -
Pliocene Coralline Algae, South Of Safaga (Red Sea, Egypt)
( Qatar University , 1984 , Article)Coralline algae are highly abundant in the Pliocene succession of the area south of Safaga (Red Sea, Egypt). The articulated corallines (Corallinoideae) are represented here by a single genus, Amphiroa. The crustose coralline ... -
Investigations on the growth abnormalities of medicago sativa l. Under field conditions
( Qatar University , 1996 , Article)Morphological growth abnormalities were pursued and studied in field-grown alfalfa (Medicago sativa L.) in Al-Kharj agricultural area, south east of Riyadh. Significant differences between normal and abnormal plants were ... -
Lumping Processes of Periodic ARMA Processes
( Qatar University , 2004 , Article)In this article various lumping processes are defined for periodic ARMA (PARMA) processes, namely, the forward, the backward and the cyclic lumping processes. The inter-relations between the parameters of these lumping ... -
On Finite Group Actions On The Solid Klein Bottle
( Qatar University , 1989 , Article)In this paper we classify all G-actions on the solid Klein bottle when G= Z2 and when G= Z^ ® Z2. -
Effect Of Ca++ And Mg++ On The Binding Of Cytoplasmic And Nuclear Estradiol Receptors In Breast Cancer Of Female Patients
( Qatar University , 1993 , Article)Specific estradiol receptors were quantitatively determined in the cytosol and nuclear fractions of four cancerous breast tissues and one normal uterus. Validated methods are described for estradiol receptor assay. The ... -
The Study Of Compaction Using Seismic Velocity Analyses In East - Baghdad Oil Field (Mid - Iraq)
( Qatar University , 1995 , Article)The present study deals with estimation of empirical equations relating travel time (T) and transit time (T.T) with depth (Z) which are expressed in the forms : T = BZN + A, log T. T. = - s log Z + H For this aim, ... -
A Qualitative Approach to Direct Inference Principle
( Qatar University , 2002 , Article)In this paper,we study the suitability of a symbolic model of syllogistic reasoning and direct inference principle with the representation and the management of knowledge based on statistical information and evaluated in ... -
Delineation of charged deltaic rock genetic types in algyo-2 hydrocarbon reservoir, hungary; Based on log curve shapes
( Qatar University , 1986 , Article)Most of the deltaic sandstone reservoirs exhibit complex lithofacies as well as petrophysical variations in both time and space. Facies analysis and reconstruction of facies patterns for the Algyo-2 reservoir rocks encountered ... -
Water Relations Of Some Woodlice (Oniscidea) From Arid And Mesic Environments
( Qatar University , 1987 , Article)The desert woodlouse Porcellio evansi from Bahrain and Qatar has a transpiration rate as low or lower than recorded from other desert species. The synanthropic mesic Porsellionides pruinosus has a much higher rate, while ... -
Inhibitory Effect Of Some Oc —Aminocarboxylic Acids On Corrosion Of Aluminium In Hydrochloric Acid Solution
( Qatar University , 1992 , Article)The corrosion of metallic aluminium in 2N hydrochloric acid solution in the presence of L-alanine, L-tyrosine, L-histidine and L-tryptophan as corrosion inhibitors has been studied using hydrogen evolution and thermometric ... -
Mesozoic Igneous Activity In Egypt
( Qatar University , 1986 , Article)A geochronological sequence of the main phases of igneous activity in Egypt during the Mesozoic is presented in this paper. This is essentially based on scrutinized isotopic age data. New K / Ar ages are also included. Three ... -
Subsurface Geothermal Study In The Central Part Of The Northern Western Desert, Egypt
( Qatar University , 1983 , Article)Geothennal investigation of the studied area was carried out using the bottom hole temperatures recorded in deep wells drilled for petroleum exploration. The study revealed interesting data regarding the geothennal gradient ... -
Constituents of plants growing in qatar part xxvii: flavonoids Of cymbopogon parkeri
( Qatar University , 1995 , Article)The study of the flavonoids of Cymbopogon parkeri resulted the isolation and indentification of tricin and isoorientin. Three other flavonoids have been isolated and partially identified. -
Combined effects of gamma radiation and Some physical factors on the rate of development of culex pipiens complex(L)
( Qatar University , 1993 , Article)The present work deals with the role of some physical factors, applied separately or combined with gamma radiation on the Fj rate of development of Culex pipiens L. when treated in the pupal stage. The results showed no ... -
Solvent Effects Of The Oxidation Of Iron (II) - Tartrate Complex By Molecular Oxygen In Aqueous Solutions Of Alcohols
( Qatar University , 1985 , Article)The solvent effects on the oxidation of Fe(II)-tartrate by molecular oxygen have been investigated in aqueous acidic solutions of alcohols such as methanol, ethanol, isopropanol and t-butanol. The second-order rate constant ... -
Algal Nitrogen Fixation In The Northwestern Part Of The Arabian Gulf
( Qatar University , 1988 , Article)Nitrogen fixation and cell counts of blue-green algae and diatoms in the northwestern area of the Arabian Gulf were assayed during the (period, 7-20 November, 1984. Spatial variations indicated that the maximum rate of ... -
Enzyme production and antibiotic susceptibility of propionibacterium acnes and p. Granulosum from acne vulgaris patients and healthy persons
( Qatar University , 1996 , Article)Seventeen strains of Propionibacterium acnes and ten strains of P. granulosum were isolated from acne patients, in addition to ten isolates of each species from healthy persons. All strains were examined for their enzymatic ...
