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Possible evidence for the existence of a hairy layer at the surface of polymer latex particles
(
John Wiley & Sons, Ltd.
, 1998 , Article)
In this work, an attempt is made to verify the existence of a hairy layer at the surface of polymer latex particles, and determine its thickness under different conditions. Two systems have been studied. In one system, ...
Mercury pollution in doha (Qatar) coastal environment
(
Wiley Periodicals, Inc.
, 1994 , Article)
Surface water and sediment samples were collected from the Doha coastal area and analyzed for content of physico-chemical forms of mercury. Dissolved reactive Hg (2.9 ng L?1) represented 81.0% of the total dissolved Hg ...
Expansion of fisheries in Qatar (1980-1992): Growth of an artisanal fleet and closure of a trawling company
(
Elsevier Science B. V.
, 1995 , Article)
Total fish landings in Qatar increased from 1736 t per annum in 1980 to 7845 t in 1992. Ninetythree percent of this growth was due to an increase in the artisanal fleet exemplified by increases in: (i) numbers of vessels ...
Ac-conductivity analysis of the effects of partial dealumination and γ-irradiation on the electric features of HZSM-5
(
Elsevier
, 1996 , Article)
For illustrating such titled effects, analysis of the electric impedance, capacitance, and dielectric loss dependences on the frequency W (0.1–100 kHz) and temperature T (373–673 K) is correlated at 0.8 V for γ-irradiated ...
Evidence by ac-conductivity for the higher mobility of boron (over aluminium)-associated Brønsted sites in boron-modified HZSM-5
(
Elsevier
, 1996 , Article)
A correlation ac-conductivity analysis is performed at 102–105 Hz, 373–613 K and 0.8 V for characterizing the effect of increasing boron incorporation in HZSM-5 lattice on altered electric features in BZSM-5 samples of ...
Flavonoids from Centaurea sinaica
(1992 , Article)
Four Newly isolated flavonoids from Centaurea sinaica
Fatty acid composition of twelve algae from the Coastal Zones of Qatar
(
Kluwer Academic Publishers
, 1997 , Article)
Fatty acid composition of twelve algal species from two different classes were determined. Three Chlorophyta species(Axetabularia calyxulux, Cladophors sericoides and Dictyosphaeria cavernosa) and nine Phaephyta species ...
Constituents of Plants Growing in Qatar, Part XXX: A New Iridoid from Cistanche Phelypaea (L) COUT
(1995 , Article)
New iridoid named phelypaeside (1) was isolated from the dried aerial parts of Cistanche phelypae (Orobanchaceae) growing in Qatar
Effect of gamma radiation on the morphology and Thermophysical properties of the pollen wall of Phoenix dactylifera L.
(
Qatar University
, 1994 , Article)
Pollen grains of Phoenix dactylifera were exposed to different doses of gamma radiation (250,500,1000 rad and 1 M rad). To access the effect of radiation on the external morphology of the pollen grains, they were examined ...
الزيادة الطبيعية ودورها في معالجة الخلل السكاني في دولة قطر
(
جامعة الكويت
, 1993 , Article)
من المعروف أن نسبة عالية من سكان دول الخليج هم من غير المواطنين ، فعلى سبيل المثال ، فهؤلاء يمثلون أكثر من 70% في كل من الكويت والإمارات وقطر . هذا البحث العلمي يحاول الإجابة على السؤال : إلى أي مدى تتمكن الزيادة الطبيعية ...