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991.
The dependencies of the effective Hall properties on a scale, obtained by means of an iterative averaging method, manifest their fractal character. The influence of an intensity of the Hall effect on the fractal character of the Hall properties was considered. Scale ranges and dimensional characteristics of the effective Hall properties behavior were calculated and discussed.  相似文献   
992.
Data on the spatial distribution of radionuclides (241Am, 239Pu, 137Cs and 152Eu) formed during nuclear explosions of different types near P2 SNTS test site are presented. Radionuclide contamination induced by the explosions varies in the concentrations of individual radionuclides, their proportions and species. Examination of the variations is a crucial task to plan remediation activities as well as those aimed at decrease of radiation risk for population and prevention of repeated contamination. Concentrations of 241Am and 239+240Pu that are the most toxic radionuclides in the area lie in hundred thousands of Bqkg?1. The most contaminated areas are classified by the radionuclide concentration, ratio and form present in soil.  相似文献   
993.
Deformed squeezed states are introduced as the q-analogues of the conventional undeformed harmonic oscillator algebra squeezed states. It is shown that the boundary vectors in the matrix-product states approach to multiparticle diffusion processes are deformed coherent or squeezed states of a deformed harmonic oscillator algebra. A deformed squeezed and coherent-states solution to the n-species stochastic diffusion boundary problem is proposed and studied.Received: 31 January 2003, Published online: 10 October 2003  相似文献   
994.
We present a full treatment of the microcanonical ensemble of the ideal hadron-resonance gas starting from a quantum-mechanical formulation which is appropriate for the statistical model of hadronization. By using a suitable transition operator for hadronization we are able to recover the results of the statistical theory, particularly the expressions of the rates of different channels. Explicit formulae are obtained for the phase space volume or density of states of the ideal relativistic gas in quantum statistics as a cluster decomposition, generalizing previous ones in the literature. The problem of the computation of averages in the hadron gas microcanonical ensemble and the comparison with canonical ones will be the main subject of a forthcoming second paper.Received: 8 July 2003, Revised: 17 October 2003, Published online: 5 May 2004  相似文献   
995.
The European Physical Journal C - The CMS experiment&;nbsp;[1] uses a general purpose detector designed for detecting the diverse signatures associated with Higgs production and new physics...  相似文献   
996.
The problem on the diffraction of the electromagnetic plane wave on a small obstacle included in a layer is investigated. The obstacle is assumed to be an elliptic cylinder whose diameter and focal distance are small in comparison with the length of the incident wave. It is proved that the small obstacle radiates as a point source, and its amplitude is proportional to the area of the cross-section and the jumps of the dielectric and magnetic constants on the interfaces. Bibliography: 5 titles.  相似文献   
997.
Pyroelectric effect in lead-magnoniobate-based solid solutions   总被引:1,自引:0,他引:1  
A coordinated study of the dielectric, electrostriction, and pyroelectric properties of the lead-magnoniobate-based ceramic solid solutions 0.9PbMg1/3Nb2/3O3-0.1PbTiO3 and 0.55PbMg1/3Nb2/3O3-0.45PbSc1/2Nb1/2O3 conducted at the relaxor transition temperatures is reported. Electromechanical coupling stimulated by the giant electrostriction effect is shown to play an essential part in the pyroelectric effect.  相似文献   
998.
999.
A direct central collision of two identical bodies of revolution is studied. A nonstationary mixed boundary-value problem with an unknown moving boundary is formulated. Its solution is represented by a series in term of Bessel functions. An infinite system of Volterra equations of the second kind for the unknown expansion coefficients is derived by satisfying the boundary conditions. The basic characteristics of the collision process are determined depending on the curvature of the frontal surface of the bodies  相似文献   
1000.
1,3-Diarylpropynones were cleanly converted to the corresponding 3-arylindenones in various superacidic media. This new, simple, one-pot reaction proved to be efficient (yields up to 95%) and very fast (reaction time less than 30 min).  相似文献   
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