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The composite comprised of zinc oxide quantum dots and poly(amic acid) (PAAc) was prepared and studied by X-rays diffraction, X-ray photoelectron spectroscopy, light scattering, UV absorbance and UV fluorescence. The UV absorbance of the ZnO/PAAc composite was found to be much larger than that of its components taken separately. The fluorescence of the ZnO/PAAc composite was found to be shifted to longer wavelengthes in comparison with pure ZnO. The presence of the dopant dodecylbenzenesulfonic acid was found to affect the observed fluorescence. 相似文献
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Template synthesis of a nickel(II) chelate with an (N'N'S'S)-donor ligand, 4'6-dimethyl-2'8-di-thio-3'7-diaza-5-oxanonanedithioamide-1'9, with a metal ion:ligand ratio of 1:1 is realized in getalin-immobilized nickel(II) hexacyanoferrate(II) matrices contacting with aqueous solutions containing dithiox-amide, acetaldehyde (pH > 10), where the latter two compounds play the role of ligand synthons. On directcontact of dithioxamide and acetaldehyde in the solution in the absence of Ni(II), the above (N,N,S,S)-donorligand does not form, and no nickel(II) chelates with this ligand can be obtained by reactions of known nickel(II) dithiooxamide complexes with acetaldehyde. 相似文献
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Hyperfine Interactions - Rotational J=1→J=0 transitions in muonic molecule, (3Heμd) J ++, in [(3Heμd)++,2e]–D and [(3Heμd)++,e]+–D collisions are considered. The... 相似文献
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Water-soluble polymers of acrylamide and acrylic acid that contain fullerene (more than 90% C60) have been prepared by the low-temperature radiation-induced living polymerization. In the absorption spectra of these polymers, a monotonically decaying absorption typical of the covalently bound fullerene or its associates is observed in the range 240–700 nm. The radiation initiation of the process allows preparation of high-purity polymers useful for designing medicinal preparations. 相似文献
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I. N. Medvedev G. A. Mikhailov 《Computational Mathematics and Mathematical Physics》2006,46(8):1442-1458
The efficiency of the “value” and “partial value” modeling related to the construction of a modeling distribution for an auxiliary random variable by multiplying the initial density by a value function is investigated. The value function usually corresponds to a solution of the adjoint equation. Conditions under which the value modeling of the initial distribution reduces the variance compared to the direct simulation are obtained. It is proved that the variance of the weighted estimate is bounded in the case of the partial value modeling. This proposition provides a basis for a method for determining whether or not the variance of the weighted estimate is bounded. This method uses the majorizing adjoint equation. Using a practically important problem in transport theory as an example, the asymptotic optimization of the distribution of the mean free path is presented. The application of the proposed method of the investigation of the variance boundedness for the analysis of the classical exponential transformation method of simulating the mean free path of a particle in the one-dimensional and the spherical variants is discussed. 相似文献
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We construct weighted modifications of statistical modeling of an ensemble of interacting particles which is connected with approximate solution of a nonlinear Boltzmann equation. 相似文献