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31.
S. S. Kovalenko K. A. Petržak K. Irmer G. Musiol 《Isotopes in environmental and health studies》2013,49(10):344-346
The TCAPM was developed to absolute and precise fission cross section measurement for neutron energies from 2 MeV up to 19 MeV. Experimental results of absolute fission cross section measurements on 233U, 235U, 238U, -237Np, 239Pu and 212Pu are given. Furthermore the TCAPM is suitable for the application of inelastic scattering of neutrons by the analysis of element contents. 相似文献
32.
33.
, - 17,6 , . , (8±4)·10–23, (7±4)·10–23 (4±2)·10–23
2. , - . 相似文献
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35.
B. Ježek I. Chudáček R. Baltramiejūnas J. Kapturauskas 《Czechoslovak Journal of Physics》1978,28(12):1367-1381
The fluorescence decay time measurements by the stroboscopic method have been made on films of amorphous poly(N-vinylcarbazole) (PVCA) and PVCA doped with 2,4,7-trinitrofluorenone (TNF). The obtained lifetimes of two excimer species have at 77 K and at 300 K values of about 43 ns and 9 ns, which are similar to other measurements. The kinetics of excimer fluorescence and energy transfer in PVCA films are described by a simple model of the Stern-Volmer type. It assumes the fast migration of localized singlet excitons and their trapping in two species of excimer traps.We propose a modified kinetic model for films of PVCA with TNF. In this model we assume besides the exciton migration and trapping on excimer and impurity traps also the direct energy transfer from two excimer species to charge transfer complexes of PVCA with TNF by the Förster dipole-dipole mechanism. The estimated critical distance of this transfer are about 10 Å. 相似文献
36.
V. A. Petržílka 《Czechoslovak Journal of Physics》1978,28(1):68-73
The averaged velocity of a test particle and the averaged velocity of a plasma in an electro-magnetic wave packet with varying frequency (e.g., a radiation pulse from pulsar) is derived. The total momentum left by the wave packet in regions of plasma inhomogeneity is found. If the plasma concentration is changing due to ionization, the plasma may be accelerated parallelly or antiparallelly to the direction of the wave packet propagation, which is relevant for a laser induced breakdown in gas.The author thanks R.Klíma for numerous discussions. 相似文献
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V. Pažma 《Czechoslovak Journal of Physics》1979,29(5):481-486
A proposal for formulation of relativistic quantum mechanics in terms of path integrals is presented.We are deeply indebted to Dr. M.Petrá for many stimulating discussions. 相似文献
39.
M. Ježabek J. Karczmarczuk M. Rożańska 《Zeitschrift fur Physik C Particles and Fields》1985,29(1):55-60
In the framework of the dual parton model we calculate the spectra of secondary antibaryons in \(\bar p\) -nucleus non-annihilation inelastic interactions. We find that the number of antibaryons in the backward hemisphere in the \(\bar p\) -nucleon centre-of-mass frame can grow with the atomic number of the nucleus. 相似文献
40.
Temperature dependence of electronic and ionic components of electric conductivity and dielectric permittivity of amorphic compounds Ag0.25Sb0.25S0.5, (AgSbS2)0.95· (SbSI)0.05 and (AgSbS2)0.9·(SbSI)0.1 in the temperature range of 290–380 K have been investigated. The experimental data show that glasses investigated are solid electrolytes. Ionic conductivity as well as dielectric permittivity of the glasses Ag-Sb-S may be changed by introduction of SbSI. 相似文献