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Sesquiterpene lactones from Pulicaria sicula
(
Elsevier
, 1988 , Article)
The aerial parts of Pulicaria sicula afforded the known xanthanolides 1-6, the guaianolides 7 and 8 as well as two new ones, the lactone 9 and the corresponding epoxide 10. Furthermore nerylisobutyrate and the thymol ...
Inhibitory effect of sodium nitrite on corrosion of lead in 0.1 M sodium hydroxide solution
(
Council of Scientific and Industrial Research
, 1988 , Article)
The effect of NaNO2 as an inhibitor for corrosion of lead in 0.1 M NaOH solution has been investigated at different temperatures using the Tafel plot technique. The concentrations of NaNO2 employed are in the range 1-5×10-5. ...
Constituents of plants growing in Qatar part XV. Chemical investigation and pharmacotoxicity of pyrrolizidine alkaloids of moltikiopsis ciliata
(
Taylor & Francis
, 1988 , Article)
Chemical study of the alkaloidal constituents of Moltikiopsis ciliata resulted in the isolation and identification of heliotrine and echinatine, in addition to other minor alkaloids. Pharmacological experiments revealed: ...
Evidence for some prostaglandins in Allium sativum extracts
(
John Wiley & Sons, Ltd.
, 1988 , Article)
Homogenized garlic (Allium sativum Linn.) was extracted successively with organic solvents and the prostaglandin-rich fraction separated. Fractionation of the extract with column chromatography was performed. TLC of the ...
Effects of herbicide and timing of removal on interference between barley and weeds
(
Blackwell Publishing Ltd
, 1988 , Article)
Field experiments were done during the rainy season of 1984�85 and 1985�86 at Harma, Qatar. A weed survey of barley fields was conducted with the primary purpose of identifying the weed vegetation present. The effects of ...
Substituted phenols as corrosion inhibitors for copper in nitric acid
(
WILEY-VCH Verlag GmbH
, 1988 , Article)
The dissolution of copper in nitric acid solution in the presence of resorcinol, o, p-aminophenols, catechol, o-cresol and salicylaldehyde as corrosion inhibitors has been studied by galvanostatic polarization and weight ...
Distribution and ultrastructure of neurosecretory cells in the cerebral ganglion of the earthworm
(
Wiley Subscription Services, Inc., A Wiley Company
, 1988 , Article)
Neurosecretory (Nsy) cells within the cerebral ganglion of Lumbricus terrestris were classified ultrastructurally. The Nsy cells within the subesophageal ganglion, nerve cord ganglion, and the peripheral nervous system ...
On the Design of Bit-Slice Processors
(
Qatar University
, 1988 , Article)
In the past decade, fixed instruction microprocessors have evolved from 4 bits to 32 bits. Their compact design and relative low cost have made them very popular with design engineers. Their use extends into a lot of ...
A short critique of the Crescent English Course
(
Qatar University
, 1988 , Article)
This paper is a short critique of the "Crescent English Course", Pupils Book 2. It falls into two parts. The first is information about the course; its aims, organization and some of its general characteristics. The second ...