Browsing Qatar University Science Journal - [From 1981 TO 2007] by Publication Date
Now showing items 41-60 of 770
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Subsurface geothermal investigation in the nile delta, egypt.
( Qatar University , 1983 , Article)The Nile Delta area is geothermally studied to define the behaviour of geothermal gradient in different wells and to determine the distribution of heat in some interesting rock formations. The geothermal investigation of ... -
On Dirichlet Problem With Singular Integral Boundary Condition
( Qatar University , 1983 , Article)In this paper a Dirichlet problem, with singular integral condition, is studied. It is shown that such problem can be reduced to a regular equation which allows us to construct the solution. -
On The Existence And Uniqueness Of Solutions Of A Functional Differential Equation
( Qatar University , 1983 , Article) -
A histological study on the neuroendocrinal system of a coleopterous insect, cy3ister tripunctatus africanus cast.
( Qatar University , 1983 , Article)Four different types of neurosecretory cells were identified in the brain of the adult water beetle, Cybister tripunctatus africanus Cast. These cells were identified into A, B, C, & D types according to their morphological ... -
Fe57 Mossbauer Study In Cobalt Substituted Magnetite
( Qatar University , 1983 , Article)The Mossbauer effect has been studied in the mixed ferrites CoxFe3_x04 (for x = 0.8, 0.9 and 1) with the spinel structure in the temperature range between 78 and 830K. The composition with x = 1, showed an expected Zeeman ... -
Pelagic Fish Resources And Their Fishery Around Qatar
( Qatar University , 1983 , Article)The existing pelagic fishery around Qatar is relatively smaller than the demersal fishery. Inshore and offshore gillnetting trolling and even bottom trawling, contribute to the production of pelagic fish species. About 30 ... -
On 2n+L-Vertex-Free Graphs
( Qatar University , 1983 , Article)We shall introduce the concepts of pseudoadjacent, pseudocoatraction and pseudoho-momorphism. We shall show, with the help of these concepts, in theorem 2 that every quadrilateral graph V (which is a 4-vertexgraph) has ... -
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 ... -
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 ... -
Biostratigraphy Of The Upper Cretaceous-Lower Tertiary Rocks Of South Jordan Based On Planktonic Foraminifera
( Qatar University , 1983 , Article)This paper deals with the Biostratigraphy of the Upper Cretaceous - Lower Tertiary rocks of Dm Rijam area. South Jordan. The study is based on 82 identified planktonic foraminiferal species. Ten foraminiferal biozones are ... -
ON THE CRYSTAL AND HYPERFINE PARAMETERS OF THE HEXAGONAL Ba Cax Sr1_xFe4 O8 MONOFERRITES
( Qatar University , 1983 , Article)The alkaline earth monoferrites BaCaxSr1-xFe4O8 with X = 0,0.5and 1, were studied by Mossbauer spectroscopy and neutron diffractometry over a wide range of temperatures (78 - 900 K). The lattice constants were obtained ... -
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. ... -
Synthesis And Biological Activity Of Some New 4-(Aminoacyl) Aminopyridines And 2-(Aminoacyl) Aminopyrimidine Derivatives
( Qatar University , 1983 , Article)The synthesis of 4-(N-Tos and N-Pht-aminoacyI) aminopyridines (III - XIV) and 2-(N-Pht-aminoacyl)-aminopyriniidines (XV-XXIV) has been achieved employing the acid chloride and carbodiimide methods. Hydrazinolysis of ... -
Blood Gases Of The Water Snake, Natrix Tesselluta, And The Desert Snake, Eryx Colubrinus
( Qatar University , 1983 , Article)1. This comparative study examines 0^ dissociation curves of blood of two colobrine snakes: an aquatic snake, Natrix tesselluta, and a desert snake, Eryx colubrinus. 2. In the case of the whole blood of the aquatic snake, ... -
Neutron Diffraction And Mossbauer Effect Study On A Mixed Rare Earth Garnet
( Qatar University , 1983 , Article)A powder sample of Y^YbFesO,; was prepared using the ceramic technique. X-ray diffraction pattern showed a single phase of the garnet type structure with a lattice constant 12.323 A". Specific heat for this composition was ... -
Copper Complexes Of Di-, Tri-, And Tetra-Peptides Containing Tryptophan, Histidine And Arginine
( Qatar University , 1983 , Article)Fifty Seven copper complexes of di-, tri-. and tetra-peptides containing tryptophan, histidine and arginine are studied spectrophotometrically. The ^a, and colour of the complexes are dependent on the sequence of the amino ... -
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 ... -
Air-Borne Fungi Of Wheat Fields In Egypt
( Qatar University , 1983 , Article)The air borne fungi of wheat fields in El-Minya Governorate were studied during the periods January-May 1977 and December 1977-May 1978 using the plating catch method on 1% glucose and 50% sucrose-Czapek's agar. Fifty-two ... -
Seasonal Fluctuation Of Non-Rhizosphere Soil Fungi In Wheat Fields In Egypt
( Qatar University , 1983 , Article)The study aims at intensive survey of fungal floras of non-rhizospheric soil in wheat fields in El-Minya Governorate over the periods December 1976 - May 1977 and December 1977 - May 1978. At 28°C, using 1% glucose-Czapek's ... -
Some Oceanographic Measurements In The Gulf Waters Around Qatar Peninsula
( Qatar University , 1983 , Article)During the winter of 1979/1980 four cruises were made to the study area. Salinity, temperature and current speed and direction were measured. The areal distribution, as well as the vertical distribution of these parameters ...
