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Pyrrolizidine alkaloids from heliotropium arbainense and h. Ovalifolium
(
Qatar University
, 1991 , Article)
Investigation of the pyrrolizidine alkaloids of Heliotropium arbainense resulted in the isolation and identification of heliotrine, europine and 7-angelylheliotrine. From H. ovalifolium three alkaloids were isolated: ...
Energy Exchange Between The Sea And The Atmosphere At Doha Harbour (Qatar) In The Arabian Gulf
(
Qatar University
, 1996 , Article)
Meteorological and oceanographic data from 1979 to 1988 have been analyzed and utilized to calculate the heat budget terms of the water at Doha Harbour. The monthly mean of solar radiation has the largest annual amplitude, ...
Geological interpretation of gravity data On a part at the western region of the High Dam Lake, South Egypt
(
Qatar University
, 1999 , Article)
The structural setting of the area was determined using the horizontal gradient of the gravitational field and the statistical analysis of its maximum trends. The gravitational field was resolved into its two components; ...
Synthesis And Spectroscopic Studies On Some Ruthenium(II) Complexes
(
Qatar University
, 1994 , Article)
The salt [RuCl2(CO)2ln has proved very useful precursor for the syntheses of a variety of organometallic complexes of transition metals. The compounds of dichlorodicarbonylruthenium(II) of the formula [RuCl2(CO)22L] or ...
Triaryl And Trialkyl Phosphites As Corrosion Inhibitors For Copper In Nitric Acid
(
Qatar University
, 1992 , Article)
Some triaryl and trialkyi phosphites were investigated as inhibitors of the corrosion of copper in nitric acid. The values of inhibitor efficiency from weight-loss measurements are in good agreement with those obtained ...
Partial characterization Of an alkalophilic extracellular Crude pectinases from a bacillus Polymyxa strain
(
Qatar University
, 1999 , Article)
A mesophilic spore forming isolate from the soil of Um-Qais region, which could produce extracellular pectinases was tentatively identified as Bacillus polymyxa. This bacterium grew best at 37°C and pH 7.0 and was able to ...
Aptian To Cenomanian Palynomorphs From The Qarun 2-1 Borehole, Western Desert, Egypt
(
Qatar University
, 1993 , Article)
Rich distinctive, miospore assemblages are recovered from four sidewall core samples obtained from the Kharita Member of Burg El Arab Formation in the Qarun 2-1 borehole located in the eastern part of the North Western ...
Comparison of mechanical shaking, ultrasonication and Homogenization as techniques used in removing attached Bacteria and their effects on the associated protozoa
(
Qatar University
, 1994 , Article)
During studying of Protozoa in the slow sand filter beds in Ashford Common Water Treatment Work (London, U.K.), it was found necessary to study the interstitial and attached bacterial populations involved with sand particles, ...
Constituents of plants growing in Qatar xxiv phytochemical investigation of salvia aegyptiaca L.
(
Qatar University
, 1994 , Article)
The study of the flavonoids revealed the isolation and identification of luteolin, luteolin 7-O- glucoside, apigenin and apigenin 7-0 glucoside; their identity was proved by m.p., TLC, UV, IR and MS. Moreover, a coumarin ...
Diffusion Problems Arising In Mathematical Biology 2
(
Qatar University
, 1996 , Article)
In this paper we consider long range diffusion, examine the local behavior of epidemics in Lp'q. In section 1 of chapter 2 we develop a model, the long range diffusion pressure in planktonic patchiness and then in secion ...