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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
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
992.
Sr-doped lanthanum cuprate was recently investigated as a potential cathode material for the intermediate temperature solid oxide fuel cell using yittria-stabilized zirconia as an electrolyte. The material thermal stability of cathode material against an electrolyte at an operating temperature plays an important role in the fuel cell's performance. In this study, the structural stability between Sr-doped lanthanum cuprate and 8 mol% yittria-stabilized zirconia was investigated by using the powder mixture and diffusion couple. The chemical reaction between these two materials in the temperature ranging from 800° to 1000°C was examined by X-ray diffraction analyses. The interfacial reaction behavior between electrode and electrolyte pellets of the reaction couple was examined by a grazing X-ray diffractometer, wavelength-dispersive X-ray analysis, and an electron probe microanalyzer. No reaction products were observed as these two materials co-fired at 800°C. The reaction products of pyrochlore La2 Zr2 O7 and perovskite SrZrO3 were formed when the specimens were heat treated at over 900°C. Because of the formation of these reaction products, the CuO was precipitated. Furthermore, an excess of SrZrO3 formation leads to the phase decomposition of perovskite Sr-doped lanthanum cuprate to La2− x Sr x CuO4 and CuO due to a decrease in strontium concentration in Sr-doped lanthanum cuprate. 相似文献
993.
A stochastic model is proposed for a basic mechanism in the formation of uncertainties in physical quantity measurements.
__________
Translated from Izmeritel'naya Tekhnika, No. 1, pp. 12–17, January, 2006. 相似文献
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.
Chr. Bargholtz L. Gerén V. N. Grebenev Yu. B. Gurov V. S. Karpukhin I. V. Laukhin B. V. Martem’yanov V. A. Matveev K. Lindberg V. S. Sopov P. -E. Tegnér B. A. Chernyshev R. R. Shafigullin I. Zartova 《Instruments and Experimental Techniques》2006,49(4):461-467
A zero-degree spectrometer for tagging η mesons on the CELSIUS/WASA facility is described, and its characteristics are presented. Tagging of η mesons is performed by detecting 3He ions produced by reaction pd → 3Heη close to the production threshold. The low background level (<2%) is in good agreement with the data obtained earlier on the SATURNE accelerator. 相似文献
996.
Results are provided for an experimental study of forming trajectories during drilling and the effect on them of cutting speed
and drilling depth.
__________
Translated from Izmeritel’naya Tekhnika, No. 8, pp. 31–33, August, 2006. 相似文献
997.
A. G. Lipnitskii A. V. Ivanov Yu. R. Kolobov 《The Physics of Metals and Metallography》2006,101(3):303-308
Grain-boundary stresses in copper for 60 symmetrical tilt grain boundaries with different orientations of the grain-boundary plane and tilt axis have been calculated by the molecular-statics method with the use of embedded-atom-method potentials of interatomic interaction. It has been established that the grain-boundary stresses are negative for grain boundaries with small excess volumes and increase approximately linearly with a buildup of the excess volume. It has been shown that the increase in grain-boundary stresses is connected with a decrease in the average coordination number of atoms, whereas pairs of closely spaced atoms in the grain-boundary core cause a negative contribution to grain-boundary stresses. 相似文献
998.
999.
Yunfeng Wang Yu Zhou Maslen D.K. Chirikjian G.S. 《Communications, IEEE Transactions on》2006,54(5):868-877
A quantity of importance in coherent optical communications is the probability density of a filtered signal in the presence of phase noise (PN). The Fokker-Planck(FP) approach has been recognized as a rigorous way to describe these statistical properties. However, computational difficulties in solving these FP equation shave prevented their widespread application. In this paper, we present a new and simple computational solution method based on techniques from noncommutative harmonic analysis on motion groups. This proposed method can easily solve all the PN FP equations with any kind of intermediate frequency filter. We also present a new derivation of PN FP equations from the viewpoint of stochastic processes. 相似文献
1000.
钢结构防火涂料应用中存在的几个问题 总被引:1,自引:0,他引:1
在分析钢结构防火涂料应用发展现状的基础上,针对实际应用中影响质量的几个问题进行了剖析,提出了改进的建议。 相似文献