Now showing items 41-60 of 2240

    • Planting Date Effect On Growth Characters And Yield Of Sorghum Under A Dry Farming-System In An Arabian Gulf Environment 

      Ismail, A.M.A.; Ali, A.H. ( Qatar University , 1996 , Article)
      Irrigated crop production in Qatar is a risky enterprise due to extreme weather conditions. Temperature is sufficiently warm to allow planting of grain sorghum [Sorghum bicolor (L.) Moench] from Aug through to Oct. Crops ...
    • On The Earthworm Fauna And Distribution In The State Of Qatar 

      Al Yousuf, Shoa'a [شعاع السيد اليوسف]; Hagras, Ahmed E. W. ( Qatar University , 1986 , Article)
      This paper is a preliminary account of the earthworms collected in February and March, 1986, from 10 localities in Qatar. Five species, Amynthas corticis (Family Megascolecidae), Dichogaster bolaui (Family Octochaetidae), ...
    • Heat Budget of the Southeastern Part of the Arabian Gulf 

      Sultan, S. A. R. [سلطان]; Elghribi, N. M. ( Qatar University , 2001 , Article)
      The surface heat fluxes through the air-sea interface for the coastal water of the southeastern part of the Arabian Gulf have been estimated using the bulk formulas. The annual mean values of the sensible, latent and back ...
    • Chemical Factors Affecting Growth and Development of Lateral Root Formation in Isolated Phaseolus vulgaris L. 

      Zeadan, Sahla Mohammad ( Qatar University , 2007 , Article)
      The initiation and subsequent emergence of lateral roots as secondary roots have been examined in attached and excised roots of Phaseolus vulgaris grown in the absence or presence of indol-3-yl acetic acid (IAA). Treatments ...
    • Proton And Carbon-13 Nuclear Magnetic Resonance Of Some 4-Amino-3-Alkyl (Aryl)-5-Thio-1,2,4-Triazolines And Their Derivatives 

      El Toukhy, Ahmed [احمد الطوخي]; Al-Kubaisi, Abdulla H.; Kenawy, Ibrahim ( Qatar University , 1991 , Article)
      The proton and carbon-13 NMR spectra of some 4-amino-3-alkyl(aryl)-5-thio-1,2,4-triazolines, some 3-alkyl-5-thio- 1,2,4-triazolines and some 4-amino-3-aryl-5-thio-l,2,4-triazoles were measured in DMSO-d6 as solvent. The ...
    • Pyrrolizidine alkaloids from alkanna orientalis (L.) Boiss 

      Hammouda, F. M. [فايزة محمود حمودة]; Ismail, S. I.; Hassan, N. M.; Tawfiq, W. A.; Kamel, A. ( Qatar University , 1992 , Article)
      Three pyrrolizidine alkaloids; 7-angelyl retronecine (I), 9-angelyl retronescine (II), and dihydroxytriangularine (III) were isolated by DCCC and VLC from Alkanna orientalis growing in Egypt. Their structures were elucidated ...
    • Screening Of Some Fungi For Uricolytic Activity 

      El Din, Mahmoud M. Nour [محمود متولي نورالدين]; El-Fallal, A. ( Qatar University , 1996 , Article)
      Twenty nine species of fungi have been tested for their uricase activity. Only twenty two species of them have the ability to produce uricases. Most of the uncapable fungi to produce uricases belong to Basidiomycotina. ...
    • Separation of Two Forms of Extracellular p-glucosidase From a Thermotolerant Aspergillus niveus 

      Taj Aldeen, Saad J. [سعد جابر تاج الدين] ( Qatar University , 2003 , Article)
      Two forms of P-glucosidase ((3-D-glucoside glucohydrolase, EC 3.2.1.21) from the culture filtrate of Aspergillus niveus were separated and partially purified by gel chromatography on Sephadex G-100 column. The two forms ...
    • Studies On The Effect Of Cadmium Chloride On The Gonads Of The Developing Chick Embryos 

      El Shabaka, H. A. [حمزة احمد الشبكة] ( Qatar University , 1987 , Article)
      Cadmium chloride was injected in doses of 5, 10, 15 and 20 /xg/egg into the yolk sac of 4—day—old chick embryos. Mortality due to cadmium intaxication increased with dose increase. The mortality rate of chick embryos ...
    • 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 ...
    • Ascending urinary tract infection in rats caused by Proteus mirabilis 

      Al Murayati, H. Y. A. [حيدر المراياتي]; Al-Murayati, H. Y.; Al-Ani, I. M.; Gani, H. M. ( Qatar University , 1997 , Article)
      A model for ascending unobstructed urinary tract infection was developed in female rats to study the pathogenesis of urinary tract infection by Proteus mirabilis. Urinary bladders of rats were inoculated by I. V. cannula ...
    • Studies On The Decay Of 241Am 

      Al Houty, L [لطيفة ابراهبم الحوطي]; El-Kameesy, S. U.; Abou-Leila, H. ( Qatar University , 1989 , Article)
      The gamma-spectrum of '"Np following the <X -decay of "'Am has been studied using hyper pure Ge-detector and Ge-NaI(Tl) coincidence spectrometer. Some recently reported weak gamma transitions are confirmed, besides two ...
    • The Neurosecretory Cells and Neurosecretions in the Developmental Stages of the Cotton Leafworm -Spodoptera Littoralis (B) 

      Banhawy, M. A. [محمود احمد البنهاوي]; Anwar, Ibrahim M. ( Qatar University , 1981 , Article)
      In 1955 Nayar described two types of neurosecretory cells in lphita limbata (A- and B-types) [1]. Later, Johannson [2] classified these cells into four categories: A, B, C and D, which he regarded as motor neurones of ...
    • Reproducing Formula and Algorithm of a Familv of Biorthonormal Wavelets 

      Lehua, Mu [مو ليهوا] ( Qatar University , 2005 , Article)
      In this paper we present a family of biorthonormal wavelets generated by a MRA orthonormal wavelet, which possesses two arbitrary parameters. Then we discuss new expressions of reproducing kernel as well as the corresponding ...
    • The Antibiotic Activity Of Some Aquatic Plants And Algal Extracts From Jordan 

      Mesmar, M. N. [محمد نزار مسمار]; Abussaud, M. ( Qatar University , 1991 , Article)
      The antimicrobial activity of the extracts of three fresh water green algae, four marine green algae, two brown marine algae and five red marine algae from the Jordanian part of the Aqaba Gulf, together with four aquatic ...
    • Trace Metals In Qatari Fish And Shellfish 

      Aboul Dahab, O.; أبو الذهب, أسامة ( Qatar University , 1991 , Article)
      Fish, prawns and crabs purchased at the retail market in Doha, were analysed for cadmium, chromium, copper, lead and zinc. The results indicated significantly elevated concentrations of cadmium in the flesh of the Qatari ...
    • Two Forms Of The Backlund Transformation Of A Third Order Differential Equation 

      El Sherbiny, H. M. [حامد مصطفى الشربيني]; Mansour, M. B. ( Qatar University , 1996 , Article)
      Two explicit forms of Backlund transformation of third order dispersive differential equation are derived. The method of derivation depends on the use of a transformation that couples the equation with its modified one.
    • Thermoluminescence (TL) Response Of Gamma-Irradiated Raw Material And The Influence Of Doping By Different Activators 

      El Kolaly, M. A. [محمد عبد الفتاح القللي] ( Qatar University , 1994 , Article)
      Thermoluminescence of raw materials has been frequently employed to determine the exposure dose as well as effective energy of gamma radiation. In this work, thermoluminescence (TL) properties of cement clinker (C) and its ...
    • Diffuse Phase Transition In Non-Stoichiometric LiRbSO4 Crystals 

      Al Houty, L.; Kassem, M. E.; El-Muraikhi, M.; Mohammad, A. A. ( Qatar University , 1992 , Article)
      The influence of changing the ratio of Li2S04 on the structure transition of (RbxLi1-x)2S04 , LRS crystals, where x ranged from 0.1 to 0. 7, was studied by thermal analysis techniques in the temperature range 300 - 600 K. ...
    • Growth and protein content of wheat kernels treated with three Growth regulators 

      Abo Hamed, S. A.; Mansour, F. A.; Al-Desuquy, H. S.; أبو حامد, سامي أبو القاسم; منصور, فتحي عواد; الدسوقي, حشمت سليمان... more authors ( Qatar University , 1993 , Article)
      Alar, asulam or kinetin at different doses were sprayed on wheat plants and their effects on growth and protein of the developing kernels were investigated. Grain fresh matter was significantly increased in response to 200 ...