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The relation between the method of coupled channels for rearrangement reactions (CRC) and the bound state approximation to the channel coupling array formalism (BSCCA), advocated in recent years, is investigated in detail for a simple 3-body system expressed in terms of truncated component wavefunctions of Faddeev type. The system is described by coupled differential or integral equations that are truncated into a model space of strongly-coupled channels. It is shown that CRC can be derived from the truncated coupled equations, either in differential or integral form, provided care is taken to use the entire model space. The corresponding BSCCA in this model space can be obtained from a restrictive condition on the integral from of the coupled equations, while it cannot be obtained consistently from the differential form of the coupled equations. The boundary conditions for the component functions are discussed in detail. 相似文献
53.
W. Diemair und K. Knopf 《Fresenius' Journal of Analytical Chemistry》1964,200(3):226-232
Zusammenfassung Rückstände geben bei mehrmaligem Homogenisieren des Pflanzen-materials mit tweenhaltigem Wasser in die wäßrige Phase über, was durch nachfolgende Extraktion des Materials nachgewiesen wurde. Der 101 verdünnte Pflanzensaft eignet sich als Testmedium für 0–24 Std alte Daphnien bei einer maximalen Versuchsdauer von 6–8 Std. Phosphor-säureester und Carbamidate sind wesentlich toxischer und finden sich zu einem höheren Prozentsatz in der wäßrigen Phase als chlorierte Kohlenwasserstoffe. Die Wirkung von Insecticiden auf Daphnien ist proportional ihrer Konzentration. Eine Steigerung der Versuchstemperatur erhöht die Empfindlichkeit der Daphnien.
I. Mitteilung: Diemair, W., u. K. Knopf: Z. Ernährungsforsch., Supplementa 3 (1963). 相似文献
Summary Insecticide residues on plantmaterial are passing into the aqueous phase when the sample is homogenized with Tween 80 containing water, as has been proved by subsequent extraction of the material. The juice (di-luted 101) is suitable as test substance for 0–24 hrs, old daphniae (maximum time of experiment 6–8 hrs.). Phosphate esters and carbamates are far more toxic and are found in the aqueous phase at a higher percentage than chlorinated hydrocarbons. The effect of insecticides on daphniae is proportional to their concentration. Raising the test temperature increases the sensibility of the daphniae.
I. Mitteilung: Diemair, W., u. K. Knopf: Z. Ernährungsforsch., Supplementa 3 (1963). 相似文献
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The reactive uptake coefficients (γ) of O(3), NO(2), N(2)O(5), and NO(3) by levoglucosan, abietic acid, nitroguaiacol, and an atmospherically relevant mixture of those species serving as surrogates for biomass burning aerosol have been determined employing a chemical ionization mass spectrometer coupled to a rotating-wall flow-tube reactor. γ of O(3), NO(2), N(2)O(5), and NO(3) in the presence of O(2) are in the range of 1-8 × 10(-5), <10(-6)-5 × 10(-5), 4-6 × 10(-5), and 1-26 × 10(-3), respectively, for the investigated organic substrates. Within experimental uncertainties the uptake of NO(3) was not sensitive to relative humidity levels of 30 and 60%. NO(3) uptake experiments involving substrates of levoglucosan, abietic acid, and the mixture exhibit an initial strong uptake of NO(3) followed by NO(3) gas-phase recovery as a function of NO(3) exposure. In contrast, the uptake of NO(3) by nitroguaiacol continuously proceeds at the same efficiency for investigated NO(3) exposures. The derived oxidative power, i.e. the product of γ and atmospheric oxidant concentration, for applied oxidants is similar or significantly larger in magnitude than for OH, emphasizing the potential importance of these oxidants for particle oxidation. Estimated atmospheric lifetimes for the topmost organic layer with respect to O(3), NO(2), N(2)O(5), and NO(3) oxidation for typical polluted conditions range between 1-112 min, indicating the potential for significant chemical transformation during atmospheric transport. The contact angles determined prior to, and after heterogeneous oxidation by NO(3), representative of 50 ppt for 1 day, do not decrease and thus do not indicate a significant increase in hygroscopicity with potential impacts on water uptake and cloud formation processes. 相似文献
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Journal of Nonlinear Science - Exact variational integrators were exposed in the context of Lagrangian mechanics in Marsden and West (2001). These integrators sample the trajectories of holonomic... 相似文献