排序方式: 共有77条查询结果,搜索用时 203 毫秒
71.
通过应用Miedema热力学模型方法对添加了微量Er的Al-5Mg合金中的Er的存在形式进行了初步的分析,并结合XRD,TEM试验进行了验证。微量Er在Al-5Mg合金中主要是以Al3Er的形式存在,并且不会出现元素Mg与Er之间的金属间化合物;同时通过XRD和TEM分析证实,含微量Er(0.1%~0.7%)的Al-5Mg合金中Er是以Al3Er相存在并且弥散分布,讨论了Al3Er相与Al基体之间的取向关系,分析了Al3Er相的存在能够改善Al-5Mg合金材料的机械性能。 相似文献
72.
Xiuqin Yang Chunping Zhang Shengwen Qi Kuan Chen Jianguo Tian Guangyin Zhang 《Optik》2005,116(6):251-254
Methyl orange is an excellent nonlinear optical material. Both ordinary intense modulation holograph and the polarization holograph can be recorded in the methyl orange-polyvinyl alcohol (MO-PVA) film. The polarization state relationship among two writing beams, reading beam, and diffraction beam can be used for construction all-optical Boolean logic gate. 相似文献
73.
74.
抗滑桩设计推力计算方法研究 总被引:3,自引:0,他引:3
滑坡推力是抗滑桩设计推力的重要依据,工程中通常使用剩余推力法来计算滑坡推力。为了比较准确合理地计算出抗滑桩的设计推力,提出了在剩余推力法基础上的一种新的抗滑桩设计推力取值方法。分析极限平衡状态下和工程安全要求下各条块的剩余下滑力,选择合理的桩位,使得抗滑桩位于滑坡体的抗滑段;然后调整桩后滑体的剩余下滑力,其调整量一方面保证桩前桩后滑体满足工程安全要求,另一方面则作为抗滑桩设计推力的修正依据,其过程由程序实现。通过实例证明了该方法的合理性。同时对今后抗滑桩设计推力的合理取值提供了参考作用。 相似文献
75.
Shengwen Qi Chunping Zhang Xiuqin Yang Kuan Chen Lianshun Zhang Yongliang Liu Tang Xu Jianguo Tian 《Optik》2007,118(9):425-429
With the Z-scan method, the nonlinear optical properties of ethyl red (ER) in ethanol solution are measured by using the lasers of 441.6, 535 and 633 nm, respectively. As a result, the effective indexes of refraction n2 of CR at the three wavelengths are in the range from 10−10 to 10−9 m2 W−1. The nonlinear absorption of ER ethanol film at the three wavelengths is measured respectively. The self-diffraction of the ER solution at 441.6 and at 535 nm is investigated, respectively, and the results indicate it possesses high quality of optical limiting. 相似文献
76.
Mu Y Qiu T Li X Guan Y Zhang S Li X 《Langmuir : the ACS journal of surfaces and colloids》2011,27(8):4968-4978
Polymer latex particles were synthesized with multilayer core-shell structure via surface cross-linking emulsion polymerization. The latex core is coated with a five-layer shell. The polymerization was done in a semicontinuous fashion monitored by a dynamic laser scattering (DLS). The copolymer in each layer is designed with alternating high and low glass transition temperature (T(g)). Divinylbenzene (DVB) was added as the cross-linking agent in the synthesis of the "hard" layers to prevent the molecular diffusion from the adjacent "soft" layers. The layer-by-layer increment on the latex core is proved by the alternating changes on the film-formation capabilities of different latex emulsions at room temperature in correspondence with the variance in the T(g) of the outermost polymer layer. The detailed morphologies of the films formed by the latex with different number of layers were characterized by atom force microscopy (AFM). The deformation of the latex particles is largely depended on the nature of the polymer in the outermost layer of the latex particles. Further characterization carried out by multifrequency temperature-modulated differential scanning calorimetry (TOPEM-DSC) confirmed the layer-by-layer structure of the particles, although the molecular redistribution and the interlayer structures were observed. The work provides a routine toward the synthesis of multilayer polymer latexes. 相似文献
77.