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排序方式: 共有10000条查询结果,搜索用时 9 毫秒
991.
Electrolytic hydrogen saturation of polycrystalline aluminum leads to a significant (up to about 30%) decrease in the shear moduli G of samples. This change in G is accompanied neither by the loss of plasticity (no hydrogen-induced brittleness) nor by a change in the electric resistance (in contrast to that observed during the hydrogenation of typical hydride-forming metals and alloys, including those in the amorphous state). 相似文献
992.
A study is made of the statistical characteristics of isotropic velocity and scalar fields in supply of the kinetic energy
of turbulence from the energy of the average flow. Two models based on the distributions of the kinetic turbulence energy
and the intensity of scalar-field pulsations by wave numbers and length scales are used for calculation of the statistical
characteristics of turbulent velocity and scalar fields. The calculation results are compared to the data of the direct numerical
modeling performed under the same initial conditions.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 79, No. 1, pp. 148–154, January–February, 2006. 相似文献
993.
994.
Yu. V. Alekseev G. Yu. Alekseev V. A. Bityurin A. V. Plaskeev 《Protection of Metals》2006,42(6):526-531
A simplified topokinetic dissolution model of a solid taking into account the correlation between the dissolution rate and
the atomic surface topography enables one to interpret a linear (in semilogarithmic coordinates) segment of the steady-state
curves of the active anodic dissolution of metals. Its slope corresponds to the product of a concentration of kinks and the
elementary reaction rate, both of which exponentially depend on the potential, rather than a simple (Tafel) elementary rate
of the atom dissolution at a semi-crystal kink.
Original Russian Text ? Yu.V. Alekseev, G.Yu. Alekseev, V.A. Bityurin, A.V. Plaskeev, 2006, published in Zashchita Metallov,
2006, Vol. 42, No. 6, pp. 568–573. 相似文献
995.
S. A. Avsarkisov Z. V. Jibuti N. D. Dolidze B. E. Tsekvava 《Technical Physics Letters》2006,32(3):259-261
Laser annealing of amorphous silicon (a-Si) at different initial temperatures (77 and 300 K) has been studied. It is established that the laser-stimulated crystallization of silicon is possible at relatively low temperatures. A theoretical model is proposed, which explains this phenomenon by melting via the electron mechanism followed by recrystallization. 相似文献
996.
O. B. Gol’tsova V. S. Klekovkin O. B. Nagovitsin S. V. Antonychev 《Glass and Ceramics》2006,63(3-4):127-129
The results of experimental studies of heat losses via the enclosing structures of an operating brick-firing kiln using a
thermal imager are described.
__________
Translated from Steklo i Keramika, No. 4, pp. 24–25, April, 2006. 相似文献
997.
Gerasimov S. A. Zhikharev A. V. Berezina E. V. Zubarev G. I. Pryanichnikov V. A. 《Metal Science and Heat Treatment》2004,46(1-2):13-17
The main laws of formation of structure and properties of nitrided structural steels are studied depending on their composition, parameters of preliminary heat treatment, and nitriding modes. New factors controlling the structure and operational properties based on new concepts of the mechanism of formation of nitride particles in the nitriding process are determined. 相似文献
998.
Constrained coding as a method to increase the data rate in dispersion-managed soliton (DMS) communication systems is proposed. This approach is well known and widely used in the context of magnetic and optical recording systems. This paper shows that it is also applicable to DMS systems due to certain similarities between the underlying physical channels. Since timing jitter is an important error-generating mechanism for solitons, a coding scheme specifically designed to combat pulse shifts is also presented, and its properties in the framework of a particular information-theoretic channel model are analyzed. A connection between the model used and the real physical channel is then established. Next, the coded system is compared with the original one from the channel capacity point of view with the help of numerical examples. Finally, the fact that the application of constrained coding may alleviate soliton pulse-to-pulse interaction is exploited. This, in turn, opens the door to the usage of higher-than-usual map strengths and ultimately leads to a significant increase of up to 50% in the bit rate. 相似文献
999.
1000.