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151.
YANG YuJuan & YAN Biao School of Materials Science Engineering Tongji University Shanghai China Shanghai Key Lab of Development Application for Metal Functional Materials 《中国科学:物理学 力学 天文学(英文版)》2011,(5)
With the multi-phase field model, the unidirectional solidification with constant velocity growth and variable velocity growth of the CBr4-C2Cl6 eutectic alloy is simulated in three dimensions. The simulated results with constant velocity growth show that with the increase of pulling velocity, the morphology of the CBr4-C2Cl6 alloy evolves in the sequence of lamellar merging →lamellar-rod transition→stable lamellar growth→oscillating growth→lamellar branching. A morphology selection map is established with ... 相似文献
152.
Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps 总被引:1,自引:0,他引:1
LU Lin TENG Bin CHENG Liang SUN Liang & CHEN XiaoBo Center for Deepwater Engineering Dalian University of Technology Dalian China State Key Laboratory of Structural Analysis for Industrial Equipment State Key Laboratory of Coastal Offshore Engineering School of Civil Resource Engineering The University of Western Australia Crawly Australia Centre for Offshore Research... 《中国科学:物理学 力学 天文学(英文版)》2011,(1)
Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water waves.The numerical results are compared with experimental data available in the literature.The comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the res... 相似文献
153.
CUI YuanQing & YANG Wei School of Aerospace Engineering Applied Mechanics Tongji University Shanghai China University Office Zhejiang University Hangzhou 《中国科学:物理学 力学 天文学(英文版)》2011,(5)
Experimental results indicate three regimes for cracking in a ferroelectric double cantilever beam (DCB) under combined electromechanical loading. In the loading, the maximum amplitude of the applied electric field reaches almost twice the coercive field of ferroelectrics. Thus, the model of small scale domain switching is not applicable any more, which is dictated only by the singular term of the crack tip field. In the DCB test, a large or global scale domain switching takes place instead, which is driven... 相似文献
154.
LONG LiuRong LI HongWei ZHOU Ping FAN Chao & YIN CaiLiu College of Physics Electronic Engineering Guangxi University for Nationalities Nanning China 《中国科学:物理学 力学 天文学(英文版)》2011,(3)
We present a scheme for multiparty-controlled teleportation of an arbitrary high-dimensional GHZ-class state with a d-dimensional (N+2)-particle GHZ state following some ideas from the teleportation (Chinese Physics B, 2007, 16: 2867). This scheme has the advantage of transmitting much fewer particles for controlled teleportation of an arbitrary multiparticle GHZ-class state. Moreover,we discuss the application of this scheme by using a nonmaximally entangled state as its quantum channel. 相似文献
155.
Vibration control of the finite L-shaped beam structures based on the active and reactive power flow
LIU ChunChuan LI FengMing TANG Liang & HUANG WenHu P.O.Box School of Astronautics Harbin Institute of Technology Harbin China P.O.Box National Laboratory of Space Intelligent Control Beijing Institute of Control Engineering Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(2)
This paper analyzes the physical meaning of the active and reactive power flow in the finite L-shaped beams and studies the active vibration control of the structures based on the active and reactive power flow.The traveling wave approach is used to calculate the structural dynamic responses.Because the error of control force is inevitable in practical applications,the effects of the error of control force on the control results are studied.The study indicates that the error of control force has pronounced ... 相似文献
156.
The third-order ghost imaging with the second-order intensity correlation is theoretically and experimentally demonstrated.The resolution and visibility of the reconstructed image are discussed,and the relationship between resolution and visibility is analyzed.The theoretical results show that a tradeoff exists between the visibility and resolution of the reconstructed image;the better the image resolution,the worse the image visibility.Numerical simulations are carried out to verify this theory,and a ghost... 相似文献
157.
We create a GaN photocathode based on graded Alx Ga1-x N buffer layers to overcome the influence of buffer-emission layer interface on the photoemission of transmission-mode GaN photocathodes.A gateshaped spectral response with a 260-nm starting wavelength and a 375-nm cut-off wavelength is obtained.Average quantum efficiency is 15% and short wavelength responses are almost equivalent to long wavelength ones.The fitted interface recombination velocity is 5×104 cm/s,with negligible magnitude,proving that the design of the graded buffer layers is efficient in obtaining good interface quality between the buffer and the emission layer. 相似文献
158.
We propose employing multi-beam propagating technology to mitigate the influence of atmospheric scintillation to the wireless optical code division multiple access (WOCDMA) system and then deduce the bit error rate (BER) formulas of systems in weak and strong scintillations,respectively.According to simulation experiment results,multi-beam propagation can improve the system performance very well compared with single-beam propagating technique.Moreover,the more beams we use,the better the performance we get.When the received optical power is-30 dBm,the BER of the system employing four beams is 5 and 1 dB lower than that of using single-beam propagating technique in weak and strong scintillations,respectively. 相似文献
159.
160.