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1.
I. F. Golovnev E. I. Golovneva L. A. Merzhievsky V. M. Fomin V. E. Panin 《Physical Mesomechanics》2015,18(3):179-186
Molecular dynamics simulation was performed to study the formation of cluster structure, interfaces, and surfaces with different curvature radii in a perfect nanocrystal passed through by a nonlinear wave. It is shown that this process is a type of nanostructure self-organization in response to an external energy flux with subsequent development of a strong rotational field. 相似文献
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The results of experimental investigations on thermal nonequilibrium ionization in CO2: N2: He mixtures are presented. Measurements of electron density, ne, in vibrationally excited nitrogen were made in a supersonic flow with different CO2 contents as well as in a CO2: N2: He = 1 : 5 : 4 mixture laser gas. The mixtures were heated in a shock tube and expanded through a supersonic nozzle. Furthermore, supersonic mixing of N2 and CO2 + He was used in some experiments. The measured values of ne in the plenum chamber and in the supersonic nozzle are reported, and the processes responsible for nonequilibrium ionization in a laser-active medium are discussed. 相似文献
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In 1997 Lampert and Slater introduced parallel knock-out schemes, an iterative process on graphs that goes through several rounds. In each round of this process, every vertex eliminates exactly one of its neighbors. The parallel knock-out number of a graph is the minimum number of rounds after which all vertices have been eliminated (if possible). The parallel knock-out number is related to well-known concepts like perfect matchings, hamiltonian cycles, and 2-factors.We derive a number of combinatorial and algorithmic results on parallel knock-out numbers: for families of sparse graphs (like planar graphs or graphs of bounded tree-width), the parallel knock-out number grows at most logarithmically with the number n of vertices; this bound is basically tight for trees. Furthermore, there is a family of bipartite graphs for which the parallel knock-out number grows proportionally to the square root of n. We characterize trees with parallel knock-out number at most 2, and we show that the parallel knock-out number for trees can be computed in polynomial time via a dynamic programming approach (whereas in general graphs this problem is known to be NP-hard). Finally, we prove that the parallel knock-out number of a claw-free graph is either infinite or less than or equal to 2. 相似文献
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L. A. Blyumenfel'd A. V. Karyakin V. A. Kuz'min G. V. Fomin A. K. Chibisov S. I. Sholina 《Russian Chemical Bulletin》1969,18(11):2463-2464
Conclusions The formation of OH radicals in the photoreduction of aqueous solutions of anthraquinonesulfonic acid as the result of electron transfer from water (OH–) to a triplet molecule has been demonstrated.Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2615–2617, November, 1969. 相似文献
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A. N. Zelentskii G. V. Fomin N. V. Kutafina A. A. Berlin 《Russian Chemical Bulletin》1970,19(5):1105-1107
Conclusions Intermediate formation of 3-oxynaphthenyl-2 radical during oxidation of 3-oxythionaphthene to thioindigo was demonstrated by the inhibitor method. The 1:1 recombination product of this radical and diphenylpicrylhydrazyl was isolated. It is assumed that the postulated oxidation mechanism is general for compounds possessing a methylene group bonded to an electron-donating X group and an electron-accepting C=O group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1168–1170, May, 1970. 相似文献