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31.
32.
Haack P Limberg C Tietz T Metzinger R 《Chemical communications (Cambridge, England)》2011,47(22):6374-6376
The first structural characterisation of a copper-carbondisulfide complex revealed a hitherto unknown binding mode for CS(2): it interacts with two metal centres (Cu(I)) simultaneously via both C=S π bonds. DFT calculations showed that complex formation occurs mainly due to a donation of electron density from the copper centres into the C=S π* orbitals. 相似文献
33.
This article presents an overview over chemical pest control in agriculture. A general introduction is given to pests, active ingredients, biochemical modes of action and activity profiles. 相似文献
34.
Mauro JB Guimarães JR Hintelmann H Watras CJ Haack EA Coelho-Souza SA 《Analytical and bioanalytical chemistry》2002,374(6):983-989
Comparative tests of net mercury methylation potentials, with cultivated and macrophyte-associated periphyton and using stable ((200)HgCl(2) and CH(3)(199)HgCl) and labeled ((203)HgCl(2)) mercury, have been conducted in the Everglades nutrient removal area (Florida, USA) and in a tropical coastal Brazilian lake (RJ, Brazil). More methylmercury was formed by macrophyte-associated (up to 17% of added (203)Hg(II)) than cultivated (up to 1.6%) periphyton and methylmercury formation was lower in periphyton exposed to light (0.2%). High methylation was also observed for samples incubated with stable mercury isotopes (1.5-7.7% of added (200)Hg(II)), confirming the results obtained with labeled mercury. Simultaneous addition of (200)HgCl(2) and CH(3)(199)HgCl indicated that CH(3)(199)HgCl had no inhibitory effect on Hg methylation. The elevated methylation potentials observed in macrophytes, because of their root-associated periphyton, might contribute significantly to the high levels of methylmercury observed in Everglades biota. Comparative mercury methylation tests were also conducted in the water of a stratified temperate lake (Wisconsin, USA). Similar trends were observed for both stable and radioisotopes, with increasing mercury methylation along the depth profile. The highest levels (0.9% (203)Hg(II) and 0.8% (200)Hg(II)) were obtained below the oxic/anoxic boundary, where sulfide starts to increase, probably as a result of the intense activity of sulfate-reducing bacteria in the anoxic layer. 相似文献
35.
B. L. Clarke H. W. Hermance H. Jagoda E. Schwinger S. J. Folley E. A. Rowsell K. Schwarz und P. Haack 《Fresenius' Journal of Analytical Chemistry》1937,109(5-6):186-188
Ohne Zusammenfassung 相似文献
36.
F. L. Hahn H. Windisch H. Abel W. P. Jorissen R. Haack und F. Feigl 《Fresenius' Journal of Analytical Chemistry》1923,63(10):410-413
Ohne Zusammenfassung 相似文献
37.
Wolfgang Haack 《Mathematische Zeitschrift》1936,41(1):252-260
Ohne Zusammenfassung 相似文献
38.
Electron transport in mesoscopic conductors has traditionally involved investigations of the mean current and the fluctuations of the current. A complementary view on charge transport is provided by the distribution of waiting times between charge carriers, but a proper theoretical framework for coherent electronic systems has so far been lacking. Here we develop a quantum theory of electron waiting times in mesoscopic conductors expressed by a compact determinant formula. We illustrate our methodology by calculating the waiting time distribution for a quantum point contact and find a crossover from Wigner-Dyson statistics at full transmission to Poisson statistics close to pinch-off. Even when the low-frequency transport is noiseless, the electrons are not equally spaced in time due to their inherent wave nature. We discuss the implications for renewal theory in mesoscopic systems and point out several analogies with level spacing statistics and random matrix theory. 相似文献
39.