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161.
According to Electrodynamics in curved spacetime, the interaction between gravitational waves (GW) and electromagnetic (EM) fields will produce perturbative electromagnetic fields. In a special EM system, namely, a Gaussian beam (Gb) propagating through a static magnetic field, the photon flux along the direction of the electric field of the Gb will be only a pure perturbative photon flux,when a GW propagates along the symmetric axis of a Gaussian beam. Detailed alanysis and calculation of the photon flux along several typical surfaces are performed, and a possible optimum plane which can receive perturbative photons up to 10~4s~(-1) is proposed. It is possible to provide an important method to detection of GW. 相似文献
162.
XU Jiang WANG Wei-zhong YANG Xiu-gui WANG Hongl Disaster Control Engineering Under the State Ministry of Education Chongqing University Chongqing Chin 《保鲜与加工》2004,(12):60-62
The deformation characteristics of the fine-sandstone is studied under the loading and unloading conditions at the three different deformation-rates and the two different stress-levels. The experimental results show that there is really the plastic-loop in the deformation curve for the loading deformation curve is different from the unloading deformation curve. But the plastic-loop is nearly unchangeable since the second circulate loading. The residual-deformation is be almost zero since the second circulate loading, and that the slope of the deformation curve increases as the deformation-rate increases, and that the residual-deformation increases as the stress-levels increases. 相似文献
163.
Zhang Shiqing 《保鲜与加工》1989,(1):105-107
In this paper, by use of the pseudo-gradient vector field, the three critical points theorem in [2] is extended to the C1 function in the Ba-nach space, and therefore the three critical, points theorem in [5] is strengthened and the existence of the saddle point of the C2 function is discussed. 相似文献
164.
Mathematical model of power frequency electric field is established based on Charge Simulation Method(CSM) to analyze power frequency electric field caused by EHV lines with overhead ground wires and its effect, which are entering the megalopolis. Calculative method on the electric field under the transmission lines is analyzed and validated. According to the criterion of environmental evaluation, the distributing characteristic of electric field is summarized, in case of various arrangement manners of lines. At last, some advice and methods of eliminating electric field under the transmission lines entering the megalopolis is proposed with regard to protecting environment. 相似文献
165.
166.
In general, the process of synthesis the refractory nanoparticles Is classified as solid state, liquid state and gaseity. The new progress and development in the study of refractory nanoparticles are investigated. The synthesis technology of the refrectory nanoparticle in liquid state is discussed mostly. The refrectory nanoparticles is synthesized by the liquid state. The characteristics and the structure of the refrectory nanoparticles have been studied in this paper. 相似文献
167.
Yun Zhengqing Tan Bangding 《保鲜与加工》1993,(5):79-84
Based on [l].this paper presents a new spline-BEM for calculating 3-D electrostatic fields,in which bi-cubic B-splines are used as basis functions. The corner problem in BEM and the extreme conditions for splines are circumvented. The numerical results presented show that the global approximation .convergence and stability of the method are satisfactory. 相似文献
168.
Feng Hailiang Wu Junliang 《保鲜与加工》1997,(6):108-113
Some conceptions of stable quaternion matrices and some judging criteria are given.The Robrach theorem,Taussky theorem,Ostrowski Schneider theorem and Gerschgorin theorem are generalized to quaternion field.The conclusion about two quaternion matrices,i.e.,inferior positive matrices are unstable,interior negative matrices are stable and some other results are pointed out. 相似文献
169.
LIU Qing-song~ 《保鲜与加工》2004,(4):15-19
The mechanism of television interference is discussed from High voltage transmission line. Then the computational model is established, and scattering fields are calculated with the finite-difference time-domain(FDTD) method, and the results are visualized. The scattering effects of High voltage transmission lines on horizontal polarization waves (corresponding to TM mode) are greater than on vertical polarization waves (corresponding to TE mode). 相似文献
170.