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51.
A newly designed cylindrical optical micro-rotator which has slopes for trapping and rotation on its upper surface is proposed. The cylindrical shape is effective in decreasing viscous drag force (damping factor) in the medium. A ray-tracing method considering the beam waist is employed to analyze the radiation pressure exerted on the upper surface of the rotator. We have demonstrated optical trapping and high speed rotation for various optical beam parameters such as the lens numerical aperture and the Gaussian mode profile as well as rotator shape parameters including oblique angle, height and diameter. 相似文献
52.
Zhong-Min Cai 《Acta Mechanica Solida Sinica》1991,4(1):89-99
In this paper an analytical solution for finite deformation at the simple extension of a hypoelastic cylindrical bar of grade zero under constant velocity is obtained. It is found that the difference between stress-strain curves at different tensile velocities is only due to the inertial terms in the solution. The axial stress due to inertia increases with the square of ratio of tensile velocities. 相似文献
53.
Scattering of obliquely incident plane acoustic wave by an air-filled, transversely isotropic cylindrical shell immersed in water is investigated theoretically and experimentally. The normal mode expansion technique is employed for analyzing the scattering field, and then resonance modes of the shell appearing in modal scattering form functions are identified performing the resonance scattering analysis. Dispersion curves for Sholte-Stoneley, SH and Lamb waves are obtained and their characteristics are interpreted. Calculated backscattering and resonance spectra as well as dispersion curves are compared with those from ultrasonic experiments for two composite samples having the same nominal composition but fabricated under different conditions. Sensitive change of the dispersion curves is observed for both normal and oblique incidences, which demonstrates the feasibility of systematic inverse evaluation of damage or elastic constants of the composite shell using data from the acoustic scattering measurements. 相似文献
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The bifurcation instability problem for cylindrical shells made of particulate composites with nonlinear elastic matrix and
damaged inclusions is formulated and solved
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 8, pp. 80–91, August 2007. 相似文献
59.
A few facts related to the aberrations for toroidal and plane gratings are presented. Some design aspects of the plane grating-based
monochromator devised by Petersen (1982) are discussed. We also point out that for a cylindrical grating astigmatic correction
can be reduced and suggest that following Petersen’s scheme some improvements in the monochromator performance could be achieved
with such a grating. 相似文献
60.
直接驱动柱内爆流体力学不稳定性数值模拟 总被引:2,自引:2,他引:0
给出了LARED-S程序对直接驱动柱内爆流体力学不稳定性模拟的物理方程,介绍了一种直接驱动柱内爆靶的结构,给出了模拟中使用活动网格追踪和其他一些需要注意的问题。对OMEGA激光器直接驱动柱内爆实验物理模型进行了简化处理:使用理想气体状态方程,假设烧蚀层、标识层和内部填充材料为同一介质,只在密度上有差别;采用全电离和单温近似,在内爆过程中仅考虑热传导过程而忽略辐射和非局域电子热传导等过程的影响。模拟结果表明:LARED-S程序与LASNEX程序的计算结果基本上符合。 相似文献