Qatar University Science Journal - [From 1981 TO 2007]: Recent submissions
Now showing items 581-600 of 770
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Selectivity Coefficient Of Wire Basket Traps For Tilapia Nilotica
( Qatar University , 1984 , Article)Most methods of estimating growth and mortality rates require samples representative of the population with respect to size of one or more age groups. There is no fishing gear that exhibits equal selectivity towards fish ... -
Effects of the expected sea level rise on avicennia marina L: a case study in Qatar
( Qatar University , 1995 , Article)A simulation of the expected sea levels rise was carried out by imposing a state of protracted flooding on seedlings of the mangrove species Avicennia marina L. under natural conditions. The imposed flooding resulted in ... -
Scanning Electron Microscopy Of The Egg And The Second Stage Larva Of Toxocara Vitulorum
( Qatar University , 1996 , Article)The surface topography of the egg and 2nd stage larvae of the nematode Toxocara vitulorum are described by scanning electron microscopy. The eggs are oval and their surfaces are characterized by the presence of distinct ... -
Petrogenesis And Geochronology Of The Granitic Intrusions Of Gabal Kulyiet And Seiga, South Eastern Desert, Egypt
( Qatar University , 1986 , Article)In the South Eastern Desert of Egypt tonalite. granodiorite and granite intruded intermediate to acidic metavolcanics and volcanogenic metasedimentary rocks of Precambrian age. The geological features of these granitic ... -
Sponges (Porifera) In Submarine Caves
( Qatar University , 1999 , Article)Sponges (phylum Porifera) have the most simple and probably the most ancient body plan of the multicellular animals. They are, however, very successful in most benthic ecosystems. They are dominant in submarine caves, where ... -
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 role of radiogenic heat in maturation of organic matter within oil shales of Duwi formation in Quseir-Safaga District, Red Sea coastal area, Egypt
( Qatar University , 1997 , Article)The oil shale beds of Duwi Formation at Quseir-Safaga district in Egypt show a high content of organic matter (kerogen) and a fair pyrolysis oil yield. Kerogens of these rocks are composed mainly of marine amorphous and ... -
Geology Of Wadi Sidri Radioactive Ocurrences, Western Sinai, Egypt
( Qatar University , 1995 , Article)Geologic and radiomclric investigations have been carried out in the environs of Wadi Sidri in Western Sinai, applying a combination of various geological, geophysical and gcochcmical techniques. This work revealed the ... -
A study on summability factors of infinite series
( Qatar University , 1997 , Article)A new theorem concerning N,p q , summability factors of infinite series are deduced. -
On the direct problem and scattering data for a singular system of differential Equations with discontinuous coefficients
( Qatar University , 1996 , Article)A system of Sturm-Liouiville differential equations of order n with a density matrix function is considered. The direct problem of the considered system is studied and hence the scattering data of the problem is obtained. -
Vibrational Analysis Of TaBr5
( Qatar University , 1987 , Article)Vibrational analysis for TaBr5 is achieved on the basis of D3h symmetry and employing GF matrix method. Each vibration is quantitatively assigned according to the calculated values of the potential energy distributions. ... -
Corrosion of n-GaAs/aqueous Photoelectrochemical Cell
( Qatar University , 2005 , Article)A combination of electrochemical studies, scanning electron microscopy, SEM, and light reflectivity measurements reveals information about the corrosion of enlightened n-GaAs in various aqueous electrolytes. The corrosion ... -
Plant phenology and its relation to the cool semi-arid condition of Sana'a
( Qatar University , 1997 , Article)In the cool semi-arid highland areas of Sana'a a plant phenological study of forty two species revealed that there was one major outburst of plant emergence corresponding with the first period of the heavy rainfall which ... -
Some Inferential Problems in Finite Population Sampling
( Qatar University , 2004 , Article)We review some results in problems of estimating a finite population total (mean) through a sample sur¬vey. Section 2 considers inference under a fixed population model and Section 3 addresses the same prob¬lem when the ... -
Comparison of antibiotic susceptibilities of four species of coagulase-negative staphylococci isolated rom normal skin and acne Lesions: a statistical approach
( Qatar University , 1996 , Article)Ten strains of each of four species of coagulase negative staphylococci: S. epidermidis, S. hominis, S. capitis, and S. cohnii isolated from both acne lesion and normal skin (total 80 strains) were tested for their antibiotic ... -
Weed Communities Of Date Palm In Eastern Arabia
( Qatar University , 1992 , Article)The present study deals with the recognition and description of the weed communities of date palm plantations in Al-Hassa Oasis, . Eastern Arabia. Thirty three communities are recognized. They are classified, after the ... -
The marine Mollusca of the Qatari waters, Arabian Gulf
( Qatar University , 1997 , Article)The species composition of the mollusca community in the Qatari waters of the Arabian Gulf, is reported. Data were obtained from analysis of samples collected during 1996 - 1997. A total of 246 species were recorded, ... -
The effect of temperature and relative humidity on survival of unfed hyalomma impeltatum (acarina: ixodidae)
( Qatar University , 1991 , Article)This work investigates survival of unfed Hyalomma impeltatum in which 8089 larvae, 3946 nymphs, 2058 males and 2304 females held at different combinations of temperature (21, 25, 29 and 34°C) and relative humidity (RH) ... -
Effect Of Cobra Naja Haje Venom On The Adrenal Activity In Rabbits
( Qatar University , 1989 , Article)Injection of rabbits with a sublethal dose (0.2mg/kg) of Naja haje venom induced an increase in serum cortisol, free cholesterol, glucose and potassium ions. A decrease in total cholesterol and sodium ions was observed ... -
Evaluation of methods for screening of extracellular cellulase In filamentous fungi
( Qatar University , 1996 , Article)Twenty-eight fungal species belonging to fifteen genera were isolated from Saudi Arabian soil and were screened for the production of extracellular cellulase enzymes. Cleared-zone technique, cellulose azure method and agar ...
