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51.
G. M. Feldman 《Doklady Mathematics》2013,87(2):198-201
We prove some analogues of the well-known Skitovich-Darmois and Heyde characterization theorems for a second countable locally compact Abelian group X under the assumption that the distributions of the random variables have continuous positive densities with respect to a Haar measure on X and the coefficients in the linear forms considered are topological automorphisms of the group X. 相似文献
52.
The thermodynamic potential of a coal bed is calculated, and the gas pressure in the crack-pore system of the bed is shown
to be nonuniformly distributed. This pressure is high in “weak“ regions in the bed, i.e., at the sites of a high porosity,
low elastic moduli, and low solubility, as well as at high bearing pressure sites. All these phenomena are caused by the elastic
interaction of a gas with a solid-state coal frame and the possibility of the formation of a solid solution in the coal. The
relative increase in the gas pressure at these sites is estimated. The results obtained can be used to predict the localization
of explosive and outburst regions in coal beds. 相似文献
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55.
E.A. Feldman 《Topology》1973,12(3):201-227
56.
Mathematische Zeitschrift - 相似文献
57.
A new mechanism of dipole relaxation and molecular motion in normal aliphatic alcohols is suggested, based on the assumption of the existence of consequent reorientations of the molecules in chains It is shown that the experimental data obtained by different methods of dielectric spectroscopy, including TDS. can be described accurately within the framework of the model. 相似文献
58.
The knapsack problem, maximize Σmi = 1cixi when Σmi = 1aixi?b for integers xi?0, can be solved by the classical step-off algorithm. The algorithm develops a series of feasible solutions with ever-increasing objective values. We make a change in the problem so that the step-off algorithm produces a series of solutions of not necessarily increasing objective values. A point is reached when no better solutions can be found and the calculation is stopped. 相似文献
59.
I.?A.?Pshenichnov B.?L.?Berman W.?J.?BriscoeEmail author C.?Cetina G.?Feldman P.?Heimberg A.?S.?Iljinov I.?I.?Strakovsky 《The European Physical Journal A - Hadrons and Nuclei》2005,24(1):69-84
We have calculated the fission probabilities for 237Np, 233, 235, 238U, 232Th, and natPb following the absorption of photons with energies from 68 MeV to 3.77 GeV using the RELDIS Monte Carlo code. This code implements the cascade-evaporation-fission model of intermediate-energy photonuclear reactions. It includes multiparticle production in photoreactions on intranuclear nucleons, pre-equilibrium emission, and the statistical decay of excited residual nuclei via competition of evaporation, fission, and multifragmentation processes. The calculations show that in the GeV energy region the fission process is not solely responsible for the entire total photoabsorption cross-section, even for the actinides. The fission probabilities are 80-95% for 233U, 235U, and 237Np, 70-80% for 238U, and only 55-70% for 232Th. This is because certain residual nuclei that are created by deep photospallation at GeV photon energies have relatively low fission probabilities. The results of those model calculations are in reasonable agreement (at the 10% level) with recent experimental data on relative photofission cross-sections for 237Np and 233, 235, 238U (but not for 232Th or natPb) from the Saskatchewan and Jefferson Laboratories over a very wide range in photon energy. Using our calculated fission probabilities plus the total photoabsorption cross-sections per nucleon, estimated from previous cross-section data for nuclei from C to Pb, we can infer absolute photofission cross-sections for the actinide nuclei and compare them with the SAL and JLab results. The resulting discrepancies, however, clearly demonstrate the need for direct measurement of the total photoabsorption cross-sections for the heavy actinides. 相似文献
60.
[reaction: see text] The conversion of N-2,2-dichloropropionyl indole methyl ester into a tetracyclic cycloheptannelated indole model compound for the synthesis of dragmacidin E was accomplished in 10 steps. Key reactions include a Witkop cyclization to fashion a C-C bond at C(4) of the indole nucleus and a subsequent Dieckmann cyclization to deliver the desired cycloheptanoid ring. 相似文献