QU Ceased Journals: Recent submissions
Now showing items 1221-1240 of 2240
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Chemical Factors Affecting Growth and Development of Lateral Root Formation in Isolated Phaseolus vulgaris L.
( 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 ... -
Combined effects of oxygen, partial vacuum, temperature, humidity and gamma radiation on mating competitiveness of culex pipiens complex l. Males
( Qatar University , 1993 , Article)When the pupal stage of Culex pipiens complex L. male mosquito was exposed to gamma radiation (60 Gy), oxygen, partial vacuum (0.1 torr), low temperature (10°C), for one or two hours, or low humidity (31% R. H.) for 3 ... -
Investigation of Magnesium (II), Calcium (II) and Barium (II) Complexes in Aqueous Solution
( Qatar University , 2005 , Article)The ionic association constants, K6, of Mg, Ca and Ba metal ions with succinate, malate and tartrate ligands were conduct metrically determined in water at 25-40°C. The conductometric data were analysed by the Shedlovsky ... -
The Flora of The State of Qatar: Its History and Present-Day Status
( Qatar University , 2005 , Article)The history of botanical exploration in the State of Qatar is of recent origin. Various collections culminated in 2 major Floras for the State of Qatar in 1981 and 1983. Since then, further collections and focus on several ... -
Flavonoids From Cressa Cretica
( Qatar University , 2005 , Article)The aerial parts of Cressa cretica L. yielded five flavonoids that were identified as quercetin (1), quercetin-3-B-O-D-glucoside (2), kaempferol-3-O-B-D-glucoside (3), kaempferol-3-O-a-L-rhamno-(1—+6)- B-D-glucoside (a) ... -
p-cds/n-Si Anisotype Heterojunction solar cells wih Efficiency of 6.4%
( Qatar University , 2005 , Article)In the present paper, p-CdS/n-Si heterojunction solar cells are prepared for the first time by the spray pyrolysis technique. Using such low-cost method, cells with 6.4'/o AM1 conversion efficiency ina O.ZZ fill factor ... -
The Optical and Electrical Properties of Low Density Polyethylene Films in CuSo4 Solution
( Qatar University , 2005 , Article)The optical and electrical properties of pure and treated low density polyethylene (LDpE) were investigated. These measurements have been carried out at various times of immersion for LDPE films in 10% solution of CuSO+. ... -
دراسة تحليلية لتحديد المفاهيم والمهارات الرياضية اللازمة لتعلم العلوم لطلاب المرحلة المتوسطة ومدى اتقانهم لها.
( Qatar University , 1995 , Article)يؤكد العديد من المتخصصين في طرق تدريس العلوم، وكذا المؤتمرات والبحوث والدراسات على أهمية التنسيق بين الرياضيات والعلوم، كما تؤكد على أن تستقي المشكلات الرياضية من الفروع المختلفة للعلوم الطبيعية. وبدراسة الأدبيات في مجال ... -
Numerical Abundance And Species Diversity Of Surface Zooplankton In The Coastal Waters Of United Arab Emirates On The Arabian Gulf A Preliminary Study
( Qatar University , 1999 , Article)Surface zooplankton of the coastal waters of the United Arab Emirates was studied bimonthly during the period September 1997 to July 1998. Species diversity, numerical abundance and seasonal dynamics were analyzed , at six ... -
Synthesis And Reactivity Of Substituted Chromones
( Qatar University , 1992 , Article)The synthesis of 2-methyl-and 2-Styryl-6-bromo-7, 8-benzochromone and 2, 6-Dimethylchromone and their reactivity towards cyclo-addition reaction under Diels-Alder conditions and towards nucleophilic and electrophilic ... -
الابتكار واشكالية البحث عن الأصالة في التعبير الفني
( Qatar University , 1997 , Article) -
Evaluation of Electron Swarm Parameters in SF6 Using Monte Carlo Method
( Qatar University , 2005 , Article)The motion of electrons in sulfur hexafluoride (SFo) in uniform electric fields is simulated using a Monte Carlo method. The swarm parameters are evaluated and compared with experimental results of drift velocity, electron ... -
Population biology of sparid fishes in qatari waters. 1 - reproductive cycle and fecundity of longspine seabream, Argyrops spinifer (Forskal)
( Qatar University , 1993 , Article)The reproductive cycle, gonads maturation, gonado-somatic indices (GSI) and fecundity of longspine seabream Argyrops spinifer from the Arabian Gulf waters off Qatar were investigated. Bi-weekly samples representing all age ... -
Biochemical Composition Of The Squid (Loligo Vulgaris) (Mollusca) From The Mediterranean Waters Off Alexandria, Egypt
( Qatar University , 1996 , Article)The seasonal biochemical variations of the squid Loligo vulgaris from the Egyptian Mediterranean waters off Alexandria were studied during November 1989 through August 1990. Water, lipid, protein and ash contents were ... -
Preliminary Assessment of the Effect of Saline Water Used in Irrigation on the Growth of the Local Barley Cultivar (Harma)
( Qatar University , 2001 , Article)ABSTRACT The effect of gradual increase m soil salinity, using diluted solutions ofseawater, on growth and yield of the local barley cul-tivar (Harma) was examined. Harma barley did not withstand osmotic shock higher than ... -
Geochemical Model And Normalization For Heavy Metals In The Bottom Sediments, Dubai, UAE.
( Qatar University , 1999 , Article)Dubai creek can be considered as the focal point of Dubai. It has great importance for trading and aesthetic values. Total and leachable heavy metals (Cd, Co, Ni, Pb and Zn), organic carbon and total carbonate were studied ... -
Effects Of Gamma Radiation On The Sexual Attraction Of The Mediterranean Fruit Fly. Ceratitis Capitata Wied
( Qatar University , 1987 , Article)The Mediterranean fruit (ly, Ceratitis capitata Weid, was gamma irradiated as full grown pupae with 50, 70 and 90 gray. The produced adults were examined for their attractiveness to the non irradiated (normal) other sex. ... -
Constituents Of Green Beans Phaseolus Vulgaris (Lipids And Flavonoids)
( Qatar University , 1992 , Article)Chemical study of the lipid fraction resulted in the isolation and identification of a hydrocarbon fraction (n-Czg -0-033); an aliphatic alcohol fraction (C^, Czp, €30) and a sterol fraction (stigmasterol and sitosterol). ... -
Analysis Of Al Diffusion In Molten Germanium Induced By Pulsed Nd: Yag Laser Using Sims Technique
( Qatar University , 1996 , Article)In this work the volume diffusion coefficients and profile distribution of Al impurities in molten germanium have been measured using secondary-iron mass spectroscopy (SIMS) technique. Diffusion is achieved with aid of ... -
A Spreadsheet Teaching Tool For Analysis Of Pipe Networks
( Qatar University , 1997 , Article)Spreadsheets are used widely in engineering to perform several analysis and design calculations. They are also very attractive as educational tools due to their flexibility and efficiency. This paper demonstrates the use ...