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111.
Z. Kožíšek 《Czechoslovak Journal of Physics》1990,40(6):592-604
The kinetic equation of the classical homogeneous nucleation theory is rewritten in dimensionless form and it is shown that the numerical computation of the dimensionless kinetic equation is approximately 20 times faster in comparison with the original kinetic equation. The results are compared with known analytical results and with previous numerical results in the case of the constant and variable temperature for the model Li2O.2 SiO2 melt. It is shown, e.g., that under non-isothermal conditions the nucleation rate is greater than the quasistationary nucleation rate and the cluster distribution function is greater than the corresponding quasiequilibrium cluster distribution function. 相似文献
112.
113.
114.
The paper deals with the regime of advanced Bénard instabilities (described usually by the Lorenz system) in a more general system formulated firstly by Obukhov. It has been shown that triplet co-operation leads to characteristic courses where some new regularities occur. 相似文献
115.
The time dependence of the electron distribution function in helium afterglow, for pressures of 60–260 Pa, is calculated for the case in which metastable-metastable reactions are present. The time variation of the shape of the distribution function shows that careful consideration must be made of the time derivative of the distribution function in the Boltzmann equation for the calculation of the rate constant of such reactions from experimentally determined distribution function. 相似文献
116.
L. Havela P. Kratochvíl P. Lukáč B. Smola A. Svobodová 《Czechoslovak Journal of Physics》1988,38(4):384-387
The softening processes during and after the hot deformation (850–1180 C) in AISI 321 stainless steel were studied with respect to true strains
D and true strain rates
. The analysis of deformation curves indicates the occurrence of dynamic recrystallization for values of Zener-Hollomon parameterZ1015 s–1. The retardation of static recrystallization by fine Ti(N, C) precipitates is documented by microstructure studies and by variations of annealing conditions. 相似文献
117.
We discuss productions of scalar gluonium candidates in the radiativeJ/ decays. The branching ratios of such productions are estimated on the basis of the Euler-Heisenberg effective Lagrangian for gluon-photon couplings. We mention that these estimates cannot be expected to be accurate to better than within a factor 2. We show that the radiativeJ/ decays probably invalidate gluoniumgg interpretation of the GAMS meson F0(1590) and a narrow 0++ stateS lying below 1 GeV. However, a possible wide scalar effective gluonium candidate(920) is shown not to be excluded by the data on the decayJ/. We also find that the experimental data about radiativeJ/ decays presumably agree with a recently suggested interpretation of F0(1590) as being approximately a half-and-half mixture of pure 0++ gluoniumgg andSU(3)f singlet quarkoniumq¯q states. 相似文献
118.
The tensor product of two supersingleton representations
n of the Lie superalgebraosp (1, 2n) is studied forn2. The main results are as follows: (a) anticommutators and commutators of the odd generators in
n
n form a skew-symmetric representation of the Lie algebrau(n, n); (b) simple explicit form of all irreducible components of
n
n, which are labelled by a single parameterJ=0, 1, ..., has been found. Each of them is a*-representation ofosp (1, 2n) for which assertion (a) is valid. The dimension of its vacuum subspace equals
, i.e., the nondegenerate vacuum occurs for J=0 only. Basic property of this family of irreducible*-representations of osp(1, 2n) are analogous to those of massless representations of osp(1, 4).Dedicated to Academician Václav Votruba on the occasion of his eightieth birthday. 相似文献
119.
The generation of ozone under homogeneous conditions is described by a system of kinetic equations. We supposed a certain time dependence of electric field intensity inside a discharge gap. We computed the dependence of efficiency of the ozone generation on both the width and the maximum intensity of electric pulse. 相似文献
120.
M. Solache-Ríos I. García-Sosa S. Sosa-Reyes 《Journal of Radioanalytical and Nuclear Chemistry》1998,237(1-2):151-153
The sorption of cesium was studied on zeolites ZSM-5 and Y. It was found that the sorption is much higher on zeolite Y than
in ZSM-5 and it depends on the crystalline network of the zeolite. It was found as well that the main uptake mechanism involved
in both zeolites for cesium was ion exchange. 相似文献