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1.
Ovidiu Savin 《纯数学与应用数学通讯》2004,57(1):126-140
2.
S. P. Savin L. M. Zelenyi E. Amata J. Buechner J. Blecki S. I. Klimov B. Nikutowski J. L. Rauch S. A. Romanov A. A. Skalsky V. N. Smirnov P. Song K. Stasiewicz 《JETP Letters》2004,79(8):368-371
The study of the interaction between collisionless plasma flow and stagnant plasma revealed the presence of an outer boundary layer at the border of a geomagnetic trap, where the super-Alfvén subsonic laminar flow changes over to the dynamic regime characterized by the formation of accelerated magnetosonic jets and decelerated Alfvén flows with characteristic relaxation times of 10–20 min. The nonlinear interaction of fluctuations in the initial flow with the waves reflected from an obstacle explains the observed flow chaotization. The Cherenkov resonance of the magnetosonic jet with the fluctuation beats between the boundary layer and the incoming flow is the possible mechanism of its formation. In the flow reference system, the incoming particles are accelerated by the electric fields at the border of boundary layer that arise self-consistently as a result of the preceding wave-particle interactions; the inertial drift of the incoming ions in a transverse electric field increasing toward the border explains quantitatively the observed ion acceleration. The magnetosonic jets may carry away downstream up to a half of the unperturbed flow momentum, and their dynamic pressure is an order of magnitude higher than the magnetic pressure at the obstacle border. The appearance of nonequilibrium jets and the boundary-layer fluctuations are synchronized by the magnetosonic oscillations of the incoming flow at frequencies of 1–2 mHz. 相似文献
3.
Let G be either a split SO(2n+2), or a split adjoint group of type En, (n=6,7,8), over a p-adic field. In this article we study correspondences arising by restricting the minimal representation of G to various dual pairs in G. 相似文献
4.
A. S. Boreysho S. L. Druzhinin V. M. Malkov I. A. Kiselev A. V. Morozov A. E. Orlov A. V. Savin I. V. Shatalov V. I. Zapryagaev A. V. Sobolev 《Thermophysics and Aeromechanics》2007,14(4):561-576
The matter of development of a high-performance pressure recovery system (PRS) for a high-power HF/DF laser is discussed.
A sequence of design steps is proposed, which involves estimation of basic characteristics of PRS components with the help
of one-dimensional integral and semi-empirical procedures; simulation, to be performed using three-dimensional non-stationary
Navier — Stokes equations; experimental modelling aimed at verification of the calculation procedures and at refinement of
obtained parameters; and a fullscale experiment. An ejector-type system providing for recovery of pressure from 12 Torr to
atmospheric pressure in the gas-dynamic system of an HF/DF laser of several-tens-kilowatt power is developed. Matching conditions
for parameters of individual PRS components as well as joint functioning of the PRS with a continuous chemical laser in an
integral complex are analysed. Conditions for minimization of mass-dimensional characteristics of the laser-PRS complex necessary
for the development of ground-based mobile systems are identified. 相似文献
5.
Experimental results from HERA on diffractive vector meson production and their theoretical interpretation within microscopic
QCD are reviewed with an emphasis on the BFKL color dipole and k
T
-factorization approaches.
The text was submitted by the authors in English. 相似文献
6.
7.
Deardorff DR Savin KA Justman CJ Karanjawala ZE Sheppeck II JE Hager DC Aydin N 《The Journal of organic chemistry》1996,61(11):3616-3622
A two-step reaction sequence to homoallylic nitro compounds from allylic alcohols is presented. Ethoxy carbonylation of the alcohols with ethyl chloroformate provides the corresponding allylic ethyl carbonates in high yields. Exposure of these substrates to catalytic palladium(0) in CH(3)NO(2) initiates a reaction sequence, ionization-decarboxylation-nitromethylation, that culminates with the formation of nitroalkenes. The regio- and stereochemical outcomes of the nitromethyl allylation reaction can be explained by the behavior of the transient pi-allylpalladium complexes. This methodology serves as a centerpiece for the synthesis of an important carbocyclic nucleoside intermediate. 相似文献
8.
J. Hladký S. NĚmeček M. Novák A. Prokeš J. Votruba K. -F. Albrecht A. Meyer M. Sachwitz B. N. Guskov V. G. Krivokhizhin M. F. Likhachev I. A. Savin G. Vesztergombi 《Czechoslovak Journal of Physics》1977,27(11):1210-1218
Results of the first elastic K
S
o
regeneration experiment on carbon, using magnetic spark chamber spectrometer, are presented in the beam momentum interval 10p50 GeV/c. The d ifferentia cross section d/dt is reconstructed in the range 0·0025–t0·02 (GeV/c)2 and its slopeB is found to be momentum independent with an average valueB=(65±11) (GeV/c)–2. The results are in agreement with the calculations using the coherent production model. 相似文献
9.
10.
Energy-adjusted pseudopotentials for the rare earth elements 总被引:1,自引:0,他引:1
Nonrelativistic and quasirelativistic energy-adjusted pseudopotentials and optimized (7s6p5d)/[5s4p3d]-GTO valence basis sets for use in molecular calculations for fixed f-subconfigurations of the rare earth elements, La through Lu, have been generated. Atomic excitation and ionization energies from numerical HF, as well as SCF pseudopotential calculations using the derived basis sets, differ by less than 0.1 eV from numerical HF all-electron results. Corresponding values obtained from CI(SD), CEPA-1, as well as density functional calculations using the quasirelativistic pseudopotentials, are in reasonable agreement with experimental data. 相似文献