Results 21 to 30 of about 50 (50)

The Degradation of the Natural Pyrethrins in Crop Storage

Journal of Agricultural and Food Chemistry, 2003
Prolonged storage of harvested Tasmanian pyrethrum crop from Tanacetum cinerariaefolium has resulted in substantial losses of the pyrethrin esters due to the environmental conditions in the storage shed. The generation of heat, the presence of moisture and oxygen, and the microbial activity were identified as possible causes.
Bonnie L. Atkinson, Adrian J. Blackman, Helen Faber   +2 more
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ChemInform Abstract: Chemistry of Pyrethrins

ChemInform, 1995
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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Activation of Pyrethrins by Sesame Oil

Nature, 1944
IN an article on "Activation of Pyrethrins in Fly-Sprays", David and Bracey1 state that the test insect used in their work was the mosquito, Aedes aegypti, and point out that their findings may not hold for other insects. Nevertheless, the use of the term "fly-sprays" in the title is perhaps unfortunate, for we have found that many of their conclusions
E. A. Parkin, A. A. Green
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Chlorinated hydrocarbons and pyrethrins/pyrethroids

2011
Chlorinated hydrocarbons have lesser mammalian toxicity compared to organophosphate or carbamate insecticides; however, the former are not readily degradable under environmental conditions. As the usage of many chlorinated hydrocarbons has diminished in many parts of the world, synthetic pyrethroids have often served as replacements and are becoming ...
Manoj Aggarwal, Starling Kalpana, Jitendra K. Malik, Ramesh C. Gupta   +3 more
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Effects of Pyrethrins upon Blowflies

Journal of Economic Entomology, 1941
The penetration of contact insecticides through the cuticle of insects and the consequent lethal effect should depend on the characteristics of the cuticle at the time of treatment. Immediately after molting or after emergence of the adult from the pupa the cuticle is softer and thinner than at other times. Therefore one might suppose that insects that
R. A. Hook, L. D. Anderson
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Resistance to Pyrethrins and to Pyrethrins - Piperonyl Butoxide in a Wild Strain of Musca domestica L. in Sweden

Nature, 1958
ALTHOUGH synergized pyrethrins have been used for fly control for many years, there is no published record of Musca domestica L. becoming resistant to this insecticide in the field.
J. Keiding, M. Davies, C. G. Von Hofsten
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Photodecomposition of natural pyrethrins and related compounds

Pesticide Science, 1976
AbstractPresent knowledge of the photochemistry of the pyrethrins, and of the alcohols and acids from which they are constituted is summarised.
Michael J. Bullivant, Gerald Pattenden
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Pyrethrins and Allied Compounds

1955
Knowledge 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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Heck Arylation of the Natural Pyrethrins

SSRN Electronic Journal, 2022
Todd E. Markham, Peter J. Duggan, Martin R. Johnston   +2 more
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Chemistry and biosynthesis of natural pyrethrins

Pesticide Science, 1980
AbstractA short account is given of the occurrence, separation, and properties of the insecticidal ester pyrethrins from Chrysanthemum cinerariaefolium. Methods for the synthesis of the two component acids, chrysanthemic and 'chrysanthemumdicarboxylic acid' [3‐(2‐carboxyprop‐1‐enyl)‐2,2‐dimethylcyclopropanecarboxylic acid], and the alcohols ...
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