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An examination of polymerized pyrethrins
Journal of the Science of Food and Agriculture, 1950AbstractThe resinous material formed by polymerization of a highly purified pyrethrum concentrate has been examined. It was insoluble in cold light petroleum or deodorized kerosene, and gave high values for apparent pyrethrins by the Seil or mercury‐reduction methods, although it was devoid of insecticidal effect on houseflies.
A. Campbell, Wm. Mitchell
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Paper Chromatography of Pyrethrins and their Derivatives
Nature, 1956VARIOUS methods have been described for the chromatographic separation of pyrethrin-type compounds. Alumina, silica and kieselguhr have been used as adsorbents for separation of ‘pyrethrin I’ from ‘pyrethrin II’1–3. A separation of cinerin I from ‘pyrethrin I’, and ‘cinerin II’ from ‘pyrethrin II’, has almost certainly been achieved by Ward2, using ...
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Pyrethrin and Pyrethroid Insecticides
Veterinary Clinics of North America: Small Animal Practice, 1990Pyrethroids have a wide spectrum of insecticidal potency, vertebrate toxicity, and environmental stability. The exceptionally high selectivity ratios of pyrethrins and pyrethroids have resulted in their use for insect control in numerous formulations.
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Pyrethrins and Pyrethroid Insecticides
2011Pyrethrum is one of the oldest and most widely used botanical insecticides and its insecticidal properties have been known for more than 150 years. The commercial limitations of pyrethrum extracts, which are collectively known as pyrethrins, have long been recognized because of their high rate of photodegradation and a short “knockdown” (rapid ...
Jerome J. Schleier III* +1 more
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BIOASSAY SYSTEMS FOR THE PYRETHRINS
Annals of Applied Biology, 1950The special properties of pyrethrum assays with crawling insects by the film technique lend themselves to the twin cross‐over design, hitherto restricted to assays with graded responses. The conditions under which this design is appropriate, and the treatment of control responses, are discussed.
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Heck Arylation of the Natural Pyrethrins
SSRN Electronic Journal, 2022Todd E. Markham +2 more
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Pyrethrins and Allied Compounds
1955Knowledge of the value of pyrethrum flowers as an insecticidal material was kept well hidden by the original discoverers and it was not until the nineteenth century that European populations became aware of the disinfesting value of a material known as „Persian Insect Powder“.
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