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Mishandling and exposure of farm workers in Qatar to organophosphate pesticides
(
Elsevier Inc.
, 2014 , Article)
We used a combination of subjective (questionnaire) and objective (urinary metabolites) measurements to evaluate factors that can predict the exposure of farm workers in Qatar to organophosphate pesticides and to assess ...
Synthesis and biological activity of some new 3-and 6-substituted coumarin amino acid derivatives. Part I
(
Wiley-Blackwell
, 1981 , Article)
The synthesis of 6-nitrocouarrain-3-CO-amino acids and their corresponding methyl esters (II-XVII) and some dipeptide methyl esters (XVIII-XXVI) are described. 6-(N-Tosyl- or N-phthalylaminoacyl)aminocoumarin-3-carboxylic ...
Self-assembled zirconia nanotube arrays: Fabrication mechanism, energy consideration and optical activity
(
Royal Society of Chemistry
, 2014 , Article)
We present a comprehensive roadmap for the precise control of the dimensions and optical properties of anodically fabricated zirconia nanotubes. The effects of anodization time, applied voltage, solvent composition, as ...
(−)-Paniculatol, a new ent-labdane bromoditerpene from Laurencia paniculata
(
Elsevier Science Ltd.
, 1997 , Article)
(−)-Paniculatol, 1, an unusual tricyclic bromoditerpene belonging to the ent-labdane series has been identified in the red alga Laurencia paniculata collected on Qatari coasts, Arabian Gulf. The structure displays an unusual ...
Biophysical studies of the effect of high power ultrasound on the DNA solution
(
Elsevier B.V.
, 2014 , Article)
Stability and molecular size of the DNA double helical structure were studied on an aqueous solution of DNA after exposure to high power doses of continuous wave ultrasound at frequency of 20kHz. Thermal transition ...
Evaluation of pesticide residues of organochlorine in vegetables and fruits in Qatar: statistical analysis
(
Springer Verlag
, 2016 , Article)
The study aimed to examine the residues of organochlorines pesticides (OCPs) in vegetables and fruits in Qatar. A total of 127 samples was studied. Ninety percent of the imported samples recorded residues above the maximum ...
Guaianolides from Centaurea sinaica
(
Elsevier
, 1990 , Article & Report)
Three sesquiterpene lactones were isolated from the aerial parts of Centaurea sinaica: amberboin, chlorohyssopifolin A and sinaicin. The latter is reported for the first time.
Kinetic investigations into the synthesis of disulphides via tetrathiomolybdate as a sulphur-transfer reagent
(
Kluwer Academic Publishers
, 2014 , Article)
Kinetic and mechanistic aspects of the conversion of halides to disulphides using benzyl triethyl ammonium tetrathiomolybdate as sulphur-transfer reagent were investigated. The reaction follows a 1:1 stoichiometry with ...
Synthesis, immunomodulation and cytotoxic effects of vanadium (IV) complexes
(
Bentham Science Publishers B.V.
, 2014 , Article)
Vanadium is known to exhibit several bioactivities and shows potential as a pharmaceutical drug. The current studies were conducted with the goal of synthesizing a new generation of oxovanadium(IV) complexes, investigating ...
Major sterol composition of some algae from Qatar
(
Elsevier Science Ltd.
, 1995 , Article)
Thirteen macroscopic algae belonging to the three main divisions Chlorophyceae, Rhodophyceae and Phaeophyceae from the coast of Qatar (Arabian Gulf) were investigated for their sterol composition by using GC-MS coupling ...