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排序方式: 共有331条查询结果,搜索用时 218 毫秒
21.
本文给出了p—级数与广义积分∫10lnk-1x1-xdx,∫10lnk-1x1+xdx,∫10lnk-1x1-x2dx,∫10lnk-1x1+x2dx之间的关系.并通过一些p—级数的求和,给出了上述广义积分中某些积分的积分值. 相似文献
22.
一种全场三维共焦检测的新方法 总被引:11,自引:1,他引:10
提出了一种利用微光学阵更合成器件实现全场三维面形并行检测、记录的共焦方法。此方法的关键是,在共焦系统中引入一一微光学耻列合成器件来产生一点光源阵列,实现了对同一一剖面同时并行检测,并首次采用了CCD面阵像元取代上孔光阑直接截取三维信息光强。本文讨论了该方法的三信息检测原理,响应关系,给出了初步的实验结果和三维重构图。 相似文献
23.
In the alloy with solute content higher than the limiting solubility, the solute atoms that have failed to dissolve will precipitate from the solid solution and form precipitations. In this study, the Portevin-Le Chatelier (PLC) effects in annealed 5456 and 5052 aluminum alloys with different precipitation contents have been investigated under different applied strain rates. The results suggest that precipitations have significant effect on the PLC effect and the more the precipitations are, the greater the influence is. Furthermore, the solute diffusion is pipe diffusion in 5052 alloy with lower precipitation content. However, for 5456 alloy with higher precipitation content, the diffusion is no longer the case but more complex. 相似文献
24.
Wolfgang Bock Vyacheslav Futorny Mikhail Neklyudov 《Journal of Pure and Applied Algebra》2021,225(3):106535
A realization by linear vector fields is constructed for any Lie algebra which admits a biorthogonal system and for its any suitable representation. The embedding into Lie algebras of linear vector fields is in analogue to the classical Jordan—Schwinger map. A number of examples of such Lie algebras of linear vector fields is computed. In particular, we obtain examples of the twisted Heisenberg-Virasoro Lie algebra and the Schrödinger-Virasoro Lie algebras among others. More generally, we construct an embedding of an arbitrary locally convex topological algebra into the Cuntz algebra. 相似文献
25.
The infrared spectra of palladium(II) acetate crystals obtained from a benzene-acetic acid solution show that hexa-μ-acetato-triangulo-tripalladium(II)-water (2/1) i.e. the hemihydrate of hexa-μ-acetato-triangulo-tripalladium(II) was obtained. An empirical assignment of the observed bands is proposed. 相似文献
26.
Starting with the extended homogeneous balance method and a variable separation approach, a general variable separation solution of the Broer—Kaup system is derived. In addition to the usual localized coherent soliton excitations like dromions, lumps, rings, breathers, instantons, oscillating soliton excitations, peakon and fractal localized solutions, some new types of localized excitations, such as compacton and folded excitations, are obtained by introducing appropriate lower-dimensional piecewise smooth functions and multiple-valued functions, and some interesting novel features of these structures are revealed. 相似文献
27.
回顾了域上典型群的生成问题所得成果,对局部环上典型群生成问题的研究,作了一个展示,并按展示的范式,给出了辛群生成定理的证明. 相似文献
28.
29.
运用密度泛函理论下的广义梯度近似和交换关联函数对Cu吸附(SiO2)n(n=1—8)团簇的几何结构、电荷分布、稳定性和电子性质进行了较详细的研究,结果表明: Cu原子易于和带有悬挂键的Si原子作用并形成"铜岛膜"; Cu吸附(SiO2)n团簇后Si原子失去电子能力减弱,O原子得到电子能力增强;Cu(SiO2)n(n
关键词:
密度泛函理论
2)n (n=1—8)团簇')" href="#">Cu(SiO2)n (n=1—8)团簇
近红外吸收 相似文献
30.
This paper reports the theoretical study of combining Z-scan technique with Gauss-Bessel (GB) beams beside a phase object (PO) to measure the third-order nonlinear susceptibility components.By using this method,the sign of refractive index which depends on the shape of the close aperture Z-scan curve can be easily determined.Meanwhile,the magnitude of nonlinear coefficients can also be deduced by theoretical fit.The proposed method is advantageous for high sensitivity and imposes a lower stress in the cases of fragile materials,since small pulse energy is enough for the measurement of nonlinear coefficients.Predictions of the models are compared with Gaussian Z-scan measurement and GB Z-scan measurement.By using GB beams with a PO,the sensitivity of Z-scan measurements is found to be a factor of over 60 times greater than for Gaussian beams and 2 times greater than for Gaussian-Bessel beams. 相似文献