Qatar University Science Journal - [From 1981 TO 2007]: المرسلات الحديثة
السجلات المعروضة 321 -- 340 من 770
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Capabilities/limitations of landsat-tm data for bathymetric analysis of shallow marine environment: A case study
( Qatar University , 1999 , Article)The intensity of the light received by Landsat satellite sensors is inversely proportional to the path length though the sea water column. Since the light passes down to the sea floor and back again, the intensity should ... -
Effect of level of relative humidity on fungi and germination capacity of paddy (oryza sativa l.) Grains in egypt
( Qatar University , 1993 , Article)The changes in the composition of paddy grain-borne fungi in the germination capacity, and in the moisture content of paddy grains at various levels of relative humidity (r.h.) (~ 0-100%) stored at 20°C for 1, 2, 3 and 4 ... -
Calcareous Nannoplankton From The Turonian-Maastrichtian Sequence East Of El Qusaima, Ne Sinai, Egypt
( Qatar University , 1992 , Article)On terms of calcareous nannoplankton, the Turonian-Maastrichtian sequence in the studied area is subdivided into a number of nannoplankton zones. The recorded biozones represent the Turonian, Coniacian, Campanian and ... -
Mercury Pollution In Abu Kir Bay East Of Alexandria, Egypt
( 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 ... -
A Rational Exponential Model for Unconstrained Non-Linear Optimization
( Qatar University , 2002 , Article)In this Paper, a new algorithm based on the non-quadratic model is suggested for solving unconstrained optimization problems which modifies the classical conjugate gradiant methods. This technique has the same properties ... -
A rational logarithmic model for unconstrained non-linear optimization
( Qatar University , 1997 , Article)A new non-quadratic model is proposed for solving unconstrained optimisation problems which modifies and develops the classical conjugate gradient methods. The technique has the same properties as the classical conjugate ... -
Constituents of catha edulis (alkaloids, triterpenoids and related substances and saponins)
( Qatar University , 1989 , Article)The study of the alkaloids of khat samples from Egypt and Yemen revealed qualitative and quantitative differences. Cathine and the dimer of cathinone occured in both samples, while norephedine was detected only in Yemen ... -
HPLC and MS analyses of lutein-esters from tagetes patula L.
( Qatar University , 1996 , Article)Investigation of the xanthophyll esters of Tagetes patula L. flowers resulted in the isolation and identification of lutein, lutein dimyristate, lutein myristate palmitate, lutein dipalmitate and lutein palmitate stearate. ... -
Changes in some chemical constituents of stored grain and animal feed In two provinces in Saudi Arabia
( Qatar University , 1995 , Article)Changes in total acidity, total carbohydrates, reducing sugars, starch, total protein, ether soluble fraction, sodium, potassium, calcium, magnesium, total phosphorus, ash, dry and wet gluten, crude fibres and specific ... -
Floating capital pattern and biomass slope allocation method in the life history of calotropis procera (AIT.) AIT. F.
( Qatar University , 1992 , Article)Plants of the woody perennial Calotropis procera (Asclepediaceae) were grown from seed to seed-set in an open field. Smith's slope allocation and fractional-allocation or percentage methods were used to study dry matter ... -
Petrographic And Chemical Microheterogeneity In Dolomite, Bahariya Oasis, Egypt
( Qatar University , 1994 , Article)Dolomite samples from the lower member of the El-Hafhuf Formation (Turonian-Santonian) possess noticeable petrographic and chemical heterogeneity among their fabric components. Petrographically, the study samples can be ... -
Cloning and Expression of Methionine-enriched Glycinin GY4-Genes in E. Coli
( Qatar University , 2002 , Article)Cloned cDNAs encoding glycinin subunit GY4 was modified to increase methionine content. The effect of the modification was evaluated using an in vitro transcription / translation system. The modifications were carried out ... -
Mycoflora associated with dry dates in upper egypt ii. Osmophilic fungi and test of osmophilic ability
( Qatar University , 1988 , Article)19 fungal species which belong to 8 genera were collected from 30 dry date samples of which 9 species appeared on all sucrose concentrations (20%, 40% and 60%) namely, Aspergillus amstelodami, A. niger, A. raber, A. sydowii, ... -
Synthesis and Reactivity of Iron-Iridium Heterobimetallic Complexes Using Tridentate Phosphine Ligands
( Qatar University , 1994 , Article)Treatment of {Fe (CO)3 {(PPh2) 2 C=CH2}] with PPh2H gives the addition product [Fe (CO)3 {(PPh2) 2 CHCH2 PPh2}] (1). The uncoordinated phosphine group of complex 1 reacts with Ir4 (CO)12 to give mono-, di- and tri-substituted ... -
Some Results Concerning Cobb - Voxman's Conjecture
( Qatar University , 2000 , Article)In this paper we shall give some partial results of the following conjecture raised in [3]: Suppose that X is a connected space with a dispersion point p and let f: X —> X be a nonconstant continuous function. Then f(p) = p. -
Explicit Forms of Conservation Laws of a Class of Differential Equations
( Qatar University , 1994 , Article)Explicit forms of conservation laws of a class of nonlinear partial differential equations are derived; firstly from BScklund transformation and secondly from the. fundamental equations of the corresponding inverse method. -
Elliptic surfaces over a genus 1 curve with exactly the pair (I8, IV) of singular fibers
( Qatar University , 2000 , Article)In this paper we classify all minimal elliptic surfaces (TI : E —> C) over a genus 1 curve C, with a section and exactly the pair (Is, IV) of singular fibers. -
Preliminary Survey on Parasites Infecting Some Amphibian and Reptilian Species from United Arab Emirates and Qatar
( Qatar University , 2002 , Article)The common amphibian toad Bufo orientalis and four species of reptiles (Scincus muscatensis, Mabuya brevicolis, Uromastyx microlepis and Diplometopon zarudnyi) were collected from five localities in the United Arab Emirates ... -
Seasonal Variations of Acoustic Properties in Ropme Sea Area
( Qatar University , 1993 , Article)Hydrographic data collected in the periods from 1961 to 1988 are used to investigate sound speed distribution in the Regional Organization for Protection of Marine Environment (ROPME) sea area in the Gulf, during four ... -
The influence of oxygen, partial vacuum, temperature, relative humidity combined with gamma radiation on the mosquito, Culex pipiens complex l. I. Effect of exposure to temperature and relative humidity alone.
( Qatar University , 1993 , Article)The results revealed that a temperature of 10°C was the most effective temperature on pupal mortality of Culex pipiens complex L. followed by 32°C then 20 and 26°C. There was a gradual increase in pupal mortality with ...
