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101.
基于单平板的两种旋转特性(绕表面中心法及绕入射光束光轴旋转)作者提出了一种任意剪切方向的全方位剪切干涉仪,这不仅对于旋转对称发光,尤其对于非旋转对称激光束的定量检测具有十分重要的应用价值,文中描述了该仪器原理,参数及应用实例。 相似文献
102.
光学轮廓仪对光学元件表面空间波长回应的研究 总被引:2,自引:0,他引:2
在分析光学轮廓仪的空间分辨率和带限功率谱密度函数的基础上,用新测不同要品的大量数据研究了光学元件表面粗糙度测量与光学轮廓仪对表面空间波长的带限顺应关系,对由光学轮廓仪不同带宽限制内测量元件表面粗糙度不同回应所引起的不同偏差的解决办法提出了几点建议。 相似文献
103.
聚氯乙烯树脂的不饱和度和热稳定性的关系 总被引:6,自引:0,他引:6
用紫外 可见光谱法表征了不同来源的聚氯乙烯树脂(PVC)的热稳定性,用一氯化碘加成法测量了PVC的总的双键含量,用红外光谱法测量了PVC的孤立双键和共轭双键的相对含量.结果表明,PVC在加工期间的初期着色行为和长期热稳定性并不直接相关,前者取决于PVC分子链中共轭双键的含量,而后者则和孤立双键的含量有关 相似文献
104.
The photo-oxidative degradation process of polypropylene film containing iron ions was investigated via FTIR and absorbance substraction technique. It is shown that the iron ions play an important role in the decomposition of hydroperoxide and the increase of the degradation rate of polypropylene film. The amorphous region of PP film undergoes degradation prior to the crystalline one. 相似文献
105.
Jianfeng Jia Kai Huang Qingtao Pan Deyan He 《Journal of Sol-Gel Science and Technology》2007,42(1):9-12
The leakage behavior and dielectric property of BST80/MgO heterostructured thin films deposited on LaNiO3 (LNO)/Si substrates by sol-gel were investigated. The dielectric constant and the leakage current are modified by MgO insertion.
The dramatic reduction in the leakage current effectively increased the charge retention of the capacitors consisted of heterostructured
thin films as compared to the pure BST films. The significant reduction in the leakage current can be attributed to the minute
solid solubility of MgO in the BST lattice and the potential barrier built in the interface between BST and MgO layers in
the heterostructured thin films. 相似文献
106.
简要介绍了同步辐射的原理、装置和特点,综述了它在高分子取向态结晶、熔化、相分离、相转变和银纹产生等高分子研究方面的应用。 相似文献
107.
The morphology of a special blend system composed of liquid crystalline aromatic random copolyester (LCP) and semiflexible polyester PET over the whole composition range has been studied by means of polarized microscope, density measurement, DSC, FTIR and SEM. Based on the microscopic observation, it is found that under suitable mechanical mixing condition, LCP may be rather homogeneously dispersed in the PET matrix, with the middle composition range of the contents of LCP at 30--70 wt % the anisotropic and isotropic phase segregation appears, while with LCP contents over 80 wt% the blends exhibit wholly anisotropie. The DSC thermographs of the melt-pressed and quenched films show single T_(?), T_(cc) and T_m. T_(?) increases with increasing content of LCP and ap, proaches to the T_(?) of pure LCP. The experimental results indicate that the two components of this blend system are miscible, there exist some specific interactions between them. 相似文献
108.
非晶态聚对苯二甲酸乙二酯膜应力屈服机制的示差扫描量热研究 总被引:1,自引:2,他引:1
采用示差扫描量热法、应力应变测量研究了物理老化对非晶态聚对苯二甲酸乙二酯(PET)膜单轴拉伸过程中应力屈服行为的影响.结果表明,非晶高聚物经物理老化后屈服应力,应力屈服峰及热焓吸热峰均增大;屈服前后的DSC结果表明,经过屈服点后试样热焓吸热峰消失,屈服后的试样经物理老化后,应力屈服峰又再现.从凝聚缠结的观点解释了非晶高聚物物理老化和应力屈服的本质. 相似文献
109.
110.
We present ab initio calculation within the framework of the density‐functional theory (DFT) on band structure and vibrational properties of bulk V2O5. The structure of V2O5 comes from optimization of the experimental data with lattice parameters fixed. The band structure of the optimized structure has been calculated, and the result fits the experimental data very well and also gives similar results as those calculated by other methods. The phonon eigenwavenumbers of the Γ‐ point of V2O5 bulk have been calculated ab initio in density‐functional perturbation theory (DFPT). The calculated vibrational wavenumbers are in good agreement with observed infrared and Raman wavenumbers, and the predictive full phonon dispersion of bulk V2O5 has also been obtained. Further we calculated the Raman spectrum of vanadium pentoxide (V2O5) powder sample using the obtained Raman susceptibility. Calculated and measured intensities show overall good agreement. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献