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Tsyplenkov Anatoly Vanmaercke Matthias Golosov Valentin Chalov Sergey 《Journal of Soils and Sediments》2020,20(8):3266-3281
Journal of Soils and Sediments - The sediment dynamics of (peri-)glacial catchments can be highly variable and complex. Understanding these dynamics and their underlying causes is not only of... 相似文献
34.
J. H. Heckman H. G. Zuckerman C. H. Metzger B. A. Brown E. R. Bennett W. B. Ward C. L. Fitch O. H. Elmer Jhon S. Gardner Julan C. Miller Frank W. Hussey E. L. Newdick Ralph W. Donaldson Lionel Harris H. O. Werner Wm. H. Martin E. V. Hardenburg T. E. Odland Robert Schmidt Geo E. Prince Brooks D. Drain Harold L. Bailey G. S. Ralston Chase D. Gaines J. G. Milward John Tucker 《American Journal of Potato Research》1935,12(6):158-170
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G. D. Schmidt 《Forstwissenschaftliches Centralblatt》1951,70(11):641-665
Ohne ZusammenfassungMit 4 Abbildungen 相似文献
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Dr. H. Schmidt 《Journal of pest science》1944,20(1-3):10-12
Ohne Zusammenfassung
Mit 3 Abbildungen 相似文献
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Walter Oettmeier Ursula Hilp Wilfried Draber Carl Fedtke Robert R. Schmidt 《Pest management science》1991,33(4):399-409
Weeds resistant to the s-triazine herbicide atrazine also show resistance to the triazinone herbicide metribuzin. However, with highly lipophilic triazinones, thylakoids isolated from atrazine-resistant Amaranthus retroflexus (mutation at position Ser264 of the photosystem II D-1 reaction centre protein) in general show a higher pI50 value in photosystem II electron transport than those from the wild type (i.e. negative cross-resistance; ‘supersensitivity’). A quantitative structure–activity relationship (QSAR) can be established, wherein the lipophilicity of the compound plays a major role. In in-vivo experiments, it was found that the triazinone DRW2698 killed resistant Amaranthus retroflexus and Chenopodium album whereas the wild type was almost unaffected. Triazinones were further investigated in five different mutants of Chlamydomonas rheinhardtii (mutations in the D-1 protein at positions Ser264, Ala251, Leu275, Phe255, and Val219). Inhibitory activity of all triazinones was generally enhanced in the Phe255 mutant but decreased in the Val219 mutant. In the other mutants, biological activity was decreased when position 3 of the triazinone was substituted by CH3, OCH3, SCH3, NHCH3 or N(CH3)2. However, negative cross-resistance was again observed when this position was occupied by free thiol. It is therefore suggested that these two groups of triazinones orient themselves differently within the herbicide binding niche of the photosystem II D-1 protein. 相似文献
40.
The two insecticidal benzoylurea compounds, diflubenzuron and chlorfluazuron, show large differences in their toxicity against the larvae of insects like the tobacco budworm, Heliothis virescens, or the Egyptian cotton leafworm, Spodoptera littoralis, chlorfluazuron being about 100 times more toxic. This difference is due mainly to a much faster metabolism of diflubenzuron. Its half-life within the larvae is about 5 h, compared to about 50 h for chlorfluazuron. Chlorfluazuron is also the much better ovicide of the two, following injection of the compounds into the females of H. virescens. Again the difference in the rate of metabolism is the main cause. The rate of excretion of the parent benzoylureas is relatively low, but their metabolites are excreted very quickly. 相似文献