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991.
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
992.
Kukharev B. F. Stankevich V. K. Klimenko G. R. 《Russian Journal of Organic Chemistry》2003,39(5):625-629
Russian Journal of Organic Chemistry - 相似文献
993.
Thermal oxidation of polyethylene filled with dispersed copper and containing an amine antioxidant was studied. The concentration ranges in which the catalytic effect of the metal on the polymer oxidation or the stabilizing effect of the antioxidant prevails were determined. Under certain conditions, dispersed copper enhances the stabilizing effect of the antioxidant. 相似文献
994.
An ultrasonic Doppler velocimeter (UDV) is used for an experimental investigation of turbulent pipe flow at eight different Reynolds numbers (22,300–854,900). The UDV is a multipoint probe in the sense that it takes instantaneous measurements of fluid velocities at different locations simultaneously, with remarkable resolutions in space and time. The performances of the instrument with respect to the properties of the overlap layer of the turbulent flow field are investigated; the experimental results are compared with both already existing and more recently proposed scaling laws, and with other data of experimental nature. 相似文献
995.
Nešetřil and Sopena introduced the concept of oriented game chromatic number. They asked whether the oriented game chromatic
number of partial k-trees was bounded. Here we answer their question positively.
Received: January 12, 2001 Final version received: February 25, 2002 相似文献
996.
997.
V. A. Popov S. I. Lopatin L. Sh. Tsemekhman L. A. Pavlinova S. P. Kormilitsyn V. V. Barsegyan 《Russian Journal of Applied Chemistry》2003,76(10):1564-1567
Evaporation of chromium ore and concentrates was studied using high-temperature differential mass-spectrometry. The data obtained, concerning the component vapor pressures in evaporation of complex oxide systems in the range 1700-2100 K, can be used to calculate the evaporation loss in melting and to assess the possibility of utilization of the sublimates formed. 相似文献
998.
V. A. Burov I. M. Grishina O. I. Lapshenkina S. A. Morozov O. D. Rumyantseva E. G. Sukhov 《Acoustical Physics》2003,49(6):627-637
In the ultrasonic diagnostics of small-size neoplasms of biological tissues at the earliest stage of their development, an efficient way to eliminate the distorting influence of high-contrast or large inhomogeneities of the biological medium is to apply the iterative technique. A simple approach is proposed, which makes it possible with only two iteration steps to achieve an efficient focusing of the tomograph array. At the first step, the unknown distribution of the large-scale inhomogeneities of sound velocity and absorption over the scatterer is reconstructed, where the large-scale inhomogeneities are those whose size exceeds several wavelengths. At the second step, the fine structure of the scatterer is reconstructed against the large-scale background, which can be performed with a high accuracy owing to the evaluation of the background at the first step. The possibility of simultaneous reconstruction of the large-scale and fine structures by the noniterative Grinevich-Novikov algorithm is considered as an alternative. This algorithm reconstructs in an explicit form two-dimensional refractive-absorbing acoustic scatterers of almost arbitrary shape and strength. Taking into account the effects of multiple scattering, this algorithm provides resolution of the fine structure almost as good as that achieved in reconstructing the same structure against an undistorting homogeneous background. The results of numerical simulations of both algorithms are presented. 相似文献
999.
R. Norvaisa 《Lithuanian Mathematical Journal》2005,45(4):447-457
We give a characterization of Gaussian chaos laws on Banach function spaces which do not contain ℓ
∞
n
's uniformly. The result is applied to describe the convergence in law of U-processes with sample paths in certain Banach function spaces.
__________
Published in Lietuvos Matematikos Rinkinys, Vol. 45, No. 4, pp. 553–566, October–December, 2005. 相似文献
1000.
The results of experimental investigation into the mechanical properties of blends of low-density polyethylene (LDPE) with chlorinated polyethylene (CPE) in tension are presented. The specimens of pure LDPE, CPE, and nine types of LDPE/CPE blends, with different content of components at 10 wt.% intervals, were examined. Data on the influence of blend composition on the tensile stress-strain diagram, elastic modulus, yield stress, breaking stress, and ultimate elongation are obtained. The results of investigations of creep are also reported. It is found that the creep compliance (the total current compliance minus the elastic compliance) obeys the power law of creep.__________Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 3, pp. 391–404, May–June, 2005. 相似文献