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151.
ON INTERACTION OF SHOCK AND SOUND WAVE (I) 总被引:1,自引:1,他引:0
Chen Shuxing 《数学年刊B辑(英文版)》1996,17(1):35-42
This paper studies the interaction of shock and gradient wave (sound wave) of solutions to the system of inviscid isentropic gas dynamics as a model for the corresponding problems for nonlinear hyperbolic systems. The problem can be reduced to a boundary value problem in a wedged dormain, By using the method of constructing asymptotic solutions and Newton‘siteration process it is proved that if a weak shock hits a gradient wave, then the grandient wave will split into two gradient waves, while the shock continuses propagating. In this paper the author reduces the problem to a standard form and constructs asymptotic solution of the problem. The existence of the genuine solution will he given in the following paper. 相似文献
152.
Two homologous series of mesogenic materials which incorporate a 1,4-tetrafluorophenylene moiety and a terminal cyano- or nitro-substituent have been synthesized by using palladiumcatalysed coupling procedures. The compounds exhibit nematic and/or smectic A phases. 相似文献
153.
酞菁钴薄膜的折射率及吸收特性 总被引:3,自引:1,他引:2
通过真空镀法在单晶硅片上制备了酞菁钴薄膜,在波长扫描和入射角可变全自动椭圆偏振光谱仪上研究了CoPc薄膜的椭偏光谱并分析了其电子结构。 相似文献
154.
155.
156.
157.
This article concerns the existence of global smooth solution for scalar conservation laws with degenerate viscosity in 2-dimensional space. The analysis is based on successive approximation and maximum principle. 相似文献
158.
C. Scheidenberger K. Beckert P. Beller F. Bosch C. Brandau D. Boutin L. Chen B. Franzke H. Geissel R. Knöbel C. Kozhuharov J. Kurcewicz S. A. Litvinov Yu. A. Litvinov M. Mazzocco G. Münzenberg F. Nolden W. R. Plaß M. Steck B. Sun H. Weick M. Winkler 《Hyperfine Interactions》2006,173(1-3):61-66
One important goal of the ILIMA project at FAIR is the study of masses and decay properties of relativistic isomeric beams
stored and cooled in the planned storage-ring complex. A new scheme is described, where a storage-cooler ring is used for
high-resolution mass separation. Experimental results on the separation of the isobaric pair 140Pr-140Ce are presented.
P. Beller, deceased. 相似文献
159.
On the basis of Tsallis’ entropy and the joint probability factorization condition, two controversial problems existing in Tsallis’ statistics are investigated, where one is whether energy is extensive or not and the other is whether it is necessary to introduce the so-called generalized zeroth law of thermodynamics or not. The results obtained show clearly that like entropy, energy is also nonextensive in Tsallis’ statistics, and that the zeroth law of thermodynamics has been implicitly used in Tsallis’ statistics since 1988. Moreover, it is expounded that the standard energy additivity rule adopted by a great number of researchers is not suitable in Tsallis’ statistics, because its corollary is in contradiction with the zeroth law of thermodynamics. 相似文献
160.
Using the Ward-Takahashi identity, on-shell condition, bound Dirac equation and off-shell expansion, a reduced version of half off-shell virtual photon nucleon vertex has been suggested. The vertex are decomposed into several different order terms: the on-shell terms, first and second off-shell terms. The off-shell behaviour of the form factors is discussed in the one meson loop model. Using the reduced vertex and parametrized off-shell form factors the quasielastic response functions are calculated for several nuclei at ¦q¦–kf and for56Fe at large ¦q¦ up to 1.14 GeV/c and at ?q2=0.9 (GeV/c)2. The Coulomb sums are evaluated and a comparison of the theoretical prediction with data is given. The off-shell electron nucleon cross section is calculated and compared with the “cc1” off-shell extrapolation. 相似文献