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71.
K. Muthukkumaran P. Kuppusami R. Srinivasan K. Ramachandran E. Mohandas S. Selladurai 《Ionics》2007,13(1):47-50
Thermal properties of 15-mol% gadolinia doped ceria thin films (Ce0.85Gd0.15 O1.925) prepared by pulsed laser ablation on silicon substrates in the temperature range 473–973 K are presented. Thermal diffusivities
and thermal conductivities were evaluated using photoacoustic spectroscopy. The influence of grain size on thermal properties
of the films as a function of deposition temperature is studied. It is observed that the thermal diffusivity and the conductivity
of these films decreases up to 873 K and then increases with substrate temperatures. The thermal properties obtained in these
films are discussed on the basis of influence of grain size on phonon scattering. 相似文献
72.
Toshiki Yasokawa Ichirou Ishimaru Masahiro Kondo Shigeki Kuriyama Tsutomu Masaki Kaoru Takegawa Naotaka Tanaka 《Optical Review》2007,14(4):161-164
This paper describes a method for measuring the three-dimensional (3D) refractive-index distribution in a single cell. The
method can be used to observe the distribution of cell components without fluorescence staining. The two-dimensional optical
path length distributions from multiple directions are obtained by non-contact rotation of the cell. These optical path lengths
are converted into the line integrals of the refractive index, and the 3D refractive-index distribution is reconstructed by
means of computed tomography. The refractive-index distribution in a breast cancer cell can be measured using a phase-shifting
Mach—Zehnder interferometer in conjunction with proximal two-beam optical tweezers. 相似文献
73.
为提高纯相位衍射光学元件的设计效果,实现高衍射效率的三维光场衍射传播控制,在原有GS迭代算法的基础上提出了新的相位加权迭代优化设计算法。此算法的特点是,建立多衍射输出平面迭代加权算法模型,并通过反馈各个设计输出平面在迭代计算过程中的设计误差,引入一定的相位动态加权整调策略,以达到更加优化的设计效果。以此算法设计一个纯相位衍射光学元件,将输入的高斯光束在距离输入面300mm~400mm内的每个平面上变换为2×2等强度光束阵列。通过对比实验发现此方法在原有算法基础上能进一步改善算法的收敛效果,提高整体设计质量,实现更加优化的运算。 相似文献
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A comparative analysis is made of the infinite-fiber and finite-fiber models in the three-dimensional theory of stability
of composites. The results analyzed have been obtained using the three-dimensional linearized theory of stability of deformable
bodies. A historical sketch is given of the theory of stability for and approaches used in the mechanics of laminated and
fibrous composite materials
Translated from Prikladnaya Mekhanika, Vol. 44, No. 8, pp. 3–31, August 2008. 相似文献
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77.
By using the finite-part integral concepts and limit technique, the hypersingular integrodifferential equations of three-dimensional
(3D) planar interface crack were obtained; then the dominant-part analysis of 2D hypersingular integral was further used to
investigate the stress fields near the crack front theoretically, and the accurate formulae were obtained for the singular
stress fields and the complex stress intensity factors. After that, a numerical method is proposed to solve the hypersingular
integrodifferential equations of 3D planar interface crack, and the problem of elliptical planar crack is then considered
to show the application of the method. The numerical results obtained are satisfactory.
Project supported by the Foundation of Solid Mechanics Open Research Laboratory of State Education Commission at Tongji University
and the National Natural Science Foundation. 相似文献
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