Now showing items 606-625 of 2240

    • 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 ...
    • Mineral analysis of soil, euphorbia hirta l. And mycoflora from the industrial Yanbu City, Saudi Arabia 

      Hashem, Abdulwahab R. [عبد الوهاب رجب هاشم بن صادق]; Al-Farraj, M. M. ( Qatar University , 1995 , Article)
      Soil and Euphorbia hirta L. samples were collected from five localities from the industrial Yanbu city Saudi Arabia, and analysed for their metal and fungal flora. Soil type is sandy, alkaline and contained low percentage ...
    • Mineral Content Of Soil And Wild Plants From Saudi Arabia 

      Hashem, Abdulwahab R. [عبد الوهاب رجب هاشم بن صادق] ( Qatar University , 1996 , Article)
      Soil and wild plant samples were collected from different localities from the industrial Yanbu city, Saudi Arabia, and analyzed for their mineral content. Soil samples from the tested localities differed greatly and contained ...
    • Mineralogical and Chemical Properties of El-Fa Youm Clays 

      Abdel Maksoud, M. A.; Ebied, E. A.; Sabarah, B. A.; عبد المقصود, محمد علي; صبرة, برى عبد الغني; عبيد, إلهام أحمد... more authors ( Qatar University , 1993 , Article)
      El-Batts Demo Area constitutes a part of El-Fayoum province in Egypt, it is dominated by clay formations 17 meters thickness, covered in part by a thin layer of Pleistocene deposits. XRD studies reveal that smectite is ...
    • Mineralogical and Geochemical Compositions of Modern Bivalve Shells from The Mediterranean Coast Of Egypt 

      Holail, Hanafy [حنفي محمود هليل]; Tony, R. ( Qatar University , 1993 , Article)
      The stable isotopic (8 ^C and 8^O) and elemental (Sr and Mg) compositions are presented for marine mollusc Carditacea and Solenacea shells collected off the Mediterranean coast of Egypt. Based on shell microstructures and ...
    • Mineralogical And Geochemical Evaluation Of Upper Cretaceous Black Shales, Safaga District, Egypt. 

      Holail, Hanafy [حنفي محمود هليل]; El Dahhar, M.; Abd Alla, M. ( Qatar University , 1995 , Article)
      Lithologic and compositional properties of black shale and pyrite from the Upper Cretaceous phosphorite/black shale deposits (Duwi Formation) of Eastern Desert of Egypt indicate similarity in mineralogy, geochemical ...
    • The mineralogy and chemistry of cement and cement raw materials In the united arab emirates 

      Nasir, Sobhi J. [صبحي جابر نصر]; El Etr, H. ( Qatar University , 1996 , Article)
      The raw materials, clinkers and cements from different cement factories in the United Arab Emirates have been investigated using polarizing microscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), and ...
    • Mineralogy and Chemistry of Desert Roses, Ayn Dar Area, Abqaiq, Eastern Province, Saudi Arabia 

      Al Mohandis, Ahmed A. [احمد عبد القادر المهندس] ( Qatar University , 2002 , Article)
      Desert roses are crystals which usually take the form of rose petal. They have definite crystal shapes, and enclose sand grains. The desert roses were scattered along an area of about 500m2 in the Ayn Dar area, near Abqaiq, ...
    • The Mineralogy and Chemistry of Urinary Stones from the United Arab Emirates 

      Nasir, Sobhi J. [صبحي جابر نصر] ( Qatar University , 1999 , Article)
      The purpose of this study is to characterize urinary stones from the United Arab Emirates using mineralogical techniques and compare it with stones in nature. Twenty six urinary calculi were subjected to chemical analysis, ...
    • Mineralogy and Genesis of Heavy Minerals in Coastal Dune Sands, South Eastern Qatar 

      Nasir, Sobhi J. [صبحي جابر نصر]; El-Kassas, Ibrahim A.; Sadiq, A. Ali M. ( Qatar University , 1999 , Article)
      Large amounts of aeolian sand occur in the southeastern coastal zone of Qatar Peninsula as sand dunes accumulated in a vast sand field locally called " Niqyan Qatar ". The present work, carried out on a sand dune belt of ...
    • Mineralogy Of The Marrat Clay Deposits, Riyadh Region, Central Saudi Arabia 

      Al Mohandis, Ahmed A. ( Qatar University , 1989 , Article)
      Clays in the Marrat Formation, which crop out 200 km west of Riyadh, Saudi Arabia, are dominantly composed of brownish red to dark red mudstones and shales. Marrat clays are chiefly composed of kaolinite and lesser amounts ...
    • Mineralogy, petrography and manufacturing of good quality Blackboard chalk 

      Nasir, Sobhi J. [صبحي جابر نصر] ( Qatar University , 1996 , Article)
      Most of the Arabian countries produce bad quality and dusty blackboard chalk. Good quality and dustless blackboard chalk are usually imported from Europe, China, Taiwan and the United States of America. The essential raw ...
    • Mitotic Disturbances Induced By The Drug "Novalgin" In Allium Cepa Root Tips 

      El Bayoumi, A. S. [عبد العزيز البيومي]; Halieem, A. S.; Habib, A. A. ( Qatar University , 1984 , Article)
      Growing root tips of Allium cepa are treated with seven concentrations of Novalgin ranging from 2.81 x 10 4 M to 1.5 x 10 4 M for 4, 8, 24,48 and 72 hours. The frequency of mitotic phases in the treated roots varies ...
    • A Mixed Markovian Time Series Model 

      Thanoon, B. Y. [باسل يوتس ذنون]; Khalaf, A. M. ( Qatar University , 1997 , Article)
      We study a simple time series model the noise properties of the proposed model are derived. An algorithm based on the conditional mean and the conditional variance, for estimating the parameters of the proposed model is ...
    • Mixed Model For Analyzing Variability in Mortality Rates Over Time With Reference To Qatar Mortality Data 

      El bolkiny, Mohamed Tawfik ( Qatar University , 1993 , Article)
      It was observed that variability in mortality rates over time in the state of Qatar is not of binomial nature. A method of analyzing these mortality rates in the heterogeneous population is presented in this paper. Three ...
    • A Model For A Narrow-Cut Fractionating Column 

      Farag, Hassan A.; Ali, Ezzat A. ( Qatar University , 1997 , Article)
      A mathematical model was developed to simulate the operation of a narrow-cut fractionating column. The model can calculate boiling point and dew point on the feed plate, the number of liquid and vapour moles, the enthalpy ...
    • A Model Reference Adaptive Control Scheme with External Controllers 

      Al Salman, Riyadh; Nagarajan, R.; Jerwe, Dakhil H. ( Qatar University , 1989 , Article)
      A new model reference adaptive control scheme, suitable for linear multivariable discrete time systems, is proposed. A set of parameter adaptation algorithms are developed based on the validity of perfect matching between ...
    • Modelling and simulation of flexible assembly systems A petri net approach 

      Banaszak, Zbigniew [اربكنيف بناشك]; Abdul-Hussin, Mowfak H. ( Qatar University , 1995 , Article)
      This paper presents an approach towards constructing a class of Placc/TYansition nets for modelling, simulation and control of processes occurring in the Flexible Assembly Systems. Its objective lies in the formal statement ...
    • Modelling Of The Basement Surface Of Siwa-Qattara Depression Area, Northern Western Desert Of Egypt 

      Rizkalla, R. I. [رزق الله ابراهيم رزق الله]; Awad, Morad B. ( Qatar University , 1990 , Article)
      Modelling study of the basement surface of Siwa-Qattara Depression area was done through the calculation of basement depth for 62 selected points using gravity interpretation methods. The constructed basement relief map ...
    • The Models of a General Component of a Distributed Computing Systems Based On Stochastic Petri Nets 

      Serhan, Sami [سامي سرحان]; Al-Qadi, Ziad ( Qatar University , 1994 , Article)
      In this paper we propose models of a distributed computing system (DCS) based on general stochastic Petri nets (GSPN). We also propose the means to decrease the number of states. We indicate that the complexity of DCS ...