Browsing Qatar University Science Journal - [From 1981 TO 2007] by Title

Now showing items 379-398 of 770

    • Magnetic Studies on High - Tc Bi - Pb- Sr - Ca - Cu - O Ceramics 

      Al Hawery, A. S. [عبد العزيز الهويري] ( Qatar University , 1997 , Article)
      The superconducting material with a nominal composition BiI 6 Pb0 4 Sr2 Ca2 Cu3 Ox has been recently synthesized and characterized by the authors using the Q- factor method. The Q-factor data reported in this work shows ...

    • Mangrove As A Bioindicator For Environmental Pollution In The Coastal Marine Environments-Review 

      Sadooni, Fadhil N. [فاضل السعدوني]; El-Kassas, Ibrahim A. ( Qatar University , 1999 , Article)
      Mangrove stand components have been used widely as bioindicators for different types of environmental pollution including heavy metals, organic pollutants and hydrocarbons as as well as in the detection of ozone depletion ...

    • Marine Algae As Bioindicators Of Pollution Levels In The Arabian Gulf 

      Kureishy, Tariq W.; Abdel-Moati, M. A. R.; Al-Muftah, A. R. ( Qatar University , 1995 , Article)
      The extensive distribution of several marine macroalgal species makes them a potential bioindicator tool for monitoring existing levels of different types of marine pollutants in the region. The present work illustrates ...

    • The marine Mollusca of the Qatari waters, Arabian Gulf 

      Al Khayat. J. L. [جاسم عبد الله الخياط] ( 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, ...

    • A Markov Chain Model For River Flow 

      Salim, A. J. [عبد الغفور جاسم سالم]; Thanoon, B. Y. ( Qatar University , 1996 , Article)
      This paper is concerned with a trinary transformation of river flow. The transformed flow is modeled as a three-states Markov chain and both upcrossing and downcrossing problems are studied simultaneously. The stationary ...

    • A Mathematical Model Of The Dynamics Of Schistosomiasis 

      Badran, Yehia [يحيى بدران]; Sherief, Hany ( Qatar University , 1996 , Article)
      In this work the authors develop a mathematical model for the dynamics of a major helminth parasite of man, schistosomiasis. The model is a system of coupled non-linear equations. Numerical experimentations with the model ...

    • Measurements Of Radon Permeability Through Some Membranes 

      Arafa, W. [وفاء محمود عرفه] ( Qatar University , 1994 , Article)
      The diffusion of 222Rn through different types of membranes has been studied by an equilibrium method using a Si surface barrier a-detector with a resolution of 14 keV FWHM for ^'Am. The permeability constant for Aluminized ...

    • Mechanism of Dehydration of Ethanol over Alumina 

      Ebeid, Fikry M. [فكري عبيد] ( Qatar University , 1981 , Article)
      The dehydration reaction of ethanol to ether and ethylene was kinetically investigated in a flow system using •y-alumina. Pyridine was found to inhibit the formation of ethylene and ether. The rate of ethylene formation ...

    • Mechanism Of The Inhibition Afforded By Some Hydrazone Oxime Derivatives Towards Aluminium In 2m Naoh Solution 

      Fouda, A. S. [عبد العزيز السيد فوده]; Elbaz, A. M.; Moussa, M. N. ( Qatar University , 1991 , Article)
      The effect of some hydrazone oxime derivatives on the corrosion of aluminium in 2M NaOH solution was studied by polarization and weight-loss techniques. Polarization data indicated that all inhibitors tested were of a mixed ...

    • Meiofaunal Life of Man-Made Wastewater Ponds in Qatar 

      Elhag, E.A. [الحاج ابو جبر الحاج]; Kardousha, M.M.; Al-Thani, R.F.; Abdulfatih, H.A.; Al-Naimi, I.S.; ... more authors ( Qatar University , 2002 , Article)
      The meiofaunal life of two wastewater ponds around Doha City was studied for the period October 2000-October 2001. The substrate nature of the two ponds was found to be similar in mean particle sizes but the densities of ...

    • Mercury Pollution In Abu Kir Bay East Of Alexandria, Egypt 

      Aboul Dahab, O.; أبو الذهب, أسامة ( Qatar University , 1992 , Article)
      Abu Kir Bay, east of Alexandria, is subjected to substantial pollution from two direct point sources which are Tabia Pumping Station (TPS) and Lake Edku Outlet (LEO). Mercury was speciated into dissolved reactive, dissolved ...

    • Mesozoic Igneous Activity In Egypt 

      Meneisy, M. Y. [محمد يسري منيسي] ( 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 ...

    • Metabolic Effects Of Cyproterone Acetate And Corticosterone In The Chicken Callus Domesticus 

      Saleh, F. [فؤاد صالح]; Ezzat, A. R. ( Qatar University , 1990 , Article)
      The metabolic effects of corticosterone were compared with those of cyproterone acetate , a steroidogenic inhibitor with suggested corticoid-like effects. Corticosterone significantly increased serum levels of ...

    • Methylated Flavonoids From Artemisia Monosperma 

      Ismail, S. I. [شمس الدين امبابي اسماعيل]; Hammouda, F. M.; Rizk, A. M.; Hassan, N. M. ( Qatar University , 1989 , Article)
      Investigation of the flavonoid constituents of Artemisia monosperma resulted in the isolation and identification of four methylated flavonoids: quercetin 3,3',4'-trimethylether, diosmetin (luteolin 4'-methylether), ...

    • Microbial utilization of some agricultural And agro-industrial waste products for the Production of single cell protein (scp). 

      Abo Hamed, N. A. A.; أبو حامد, نبيل أبو القاسم ( Qatar University , 1993 , Article)
      The dried residues of com crop (com straw) were hydrolysed by 0.5 NH2SO4. Saccharomyces cerevisiae has been allowed to grow on media containing different concentrations of the com straw hydrolysate (CSH). The optimal ...

    • Microdetermination Of Some Organic Nitriles Using The Cyanide Ion Selective Electrode 

      Hassan, S. S. M. [سعد السيد محمد حسن] ( Qatar University , 1985 , Article)
      The response characteristics of the solid state cyanide ion selective electrode toward some organic nitriles are investigated. In 10 M KOH solution, the electrode exhibits near Nemstian response over the range of 10~2 to ...

    • Microfacies of the Upper Cretaceous-Lower Tertiary Rocks of Um Rijam Area, South Jordan 

      Youssef, M. I. [مراد يوسف] ( Qatar University , 1982 , Article)
      This paper deals, for the first time, with the microfacies of the Upper Cretaceous - Lower Tertiary rocks of south Jordan. Twenty three microfacies associations are recognized, described, discussed and illustrated. This ...

    • Microscopic Study Of The Rabbit Pancreas After Vagotomy 

      Al Muhtaseb, M. H. [محمد هاشم المحتسب]; Ali, Khalid A. ( Qatar University , 1997 , Article)
      The microscopic study of the morphological changes in the rabbit pancreas were investigated after vagotomy. Structural changes were observed in the pancreatic acinar cells and in the islets of langerhans two and three weeks ...

    • Microwave Spectra of 13CH3C15N and 13CH3 13C 15N Molecules In the Frequency Range 17-95 GHz 

      Al Share, M. [محمد الشرع] ( Qatar University , 2002 , Article)
      Some microwave frequencies of the v^ + Vg vibrational combination band for the two isotopes CH^C N and CH^ C N of methyl cyanide were measured in the frequency range 17-95 GHz, for the transitions AJ = 1<-0, AJ = 2<-1, AJ ...

    • Middle-Upper Devonian And Lower Carboniferous Miospore Assemblages From Western Desert Of Egypt 

      El Ghazaly, G. [جمال عبد المجيد الغزالي]; Ali, S. M. ( Qatar University , 1985 , Article)
      Important morphological features of some spore assemblages from Middle-Upper Devonian and Lower Carboniferous of Western Desert of Egypt are described. Comparing the present assemblages with those obtained from other ...