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Dong Zhang Yan-tao Zhu Da-hui Zhao Xin-hua Wan Qi-feng Zhou Department of Polymer Science & Engineering College of Chemistry Peking University Beijing China 《高分子科学》2000,(2):95-99
A variety of mesomorphic side-chain polysiloxanes were synthesized by using hydrosilylation reaction withdicyclopentadienylplatinum (Ⅱ) (DPPC) as the catalyst. The mesogenic groups are derivatives of stilbene with cyano or nitrotail groups. The products were characterized by DSC, X-ray deffraction and polarizing optical microscopy (POM). All thepolymers were found to have relatively low T_g and can form a smectic liquid crystal phase. 相似文献
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低强度X射线影像仪的新发展 总被引:2,自引:1,他引:1
扼要介绍国内外Lixiscope的概况。提出在国产系统中在X射线源前加置X射线准直器,X射线影像增强采用纤维光学输出窗和小孔径大面积微反,可以必普像质、扩大视场。 相似文献
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Molecular interactions of the ternary mixtures of 1-butyl-3-methylimidazolium chloride ([C4C1im]Cl)-water-2,6-dimethoxyphenol (2,6-DMP, a phenolic monomer lignin model compound) were investigated in comparison with the [C4C1im]Cl-water binary systems through attenuated total reflection infrared spectroscopy. Results indicated that the microstructures of water and [C4C1im]Cl changed with varying mole fraction of [C4C1im]Cl (xIL) from 0.01 to 1.0. This change was mainly attributed to the interactions of [C4C1im]Cl-water and the self-aggregation of [C4C1im]Cl through hydrogen bonding. The band shifts of C-H on imidazolium ring and the functional groups in 2,6-DMP indicated that the occurrence of intermolecular interactions by different mechanisms (i.e., hydrogen bonding or π-π stacking) resulted in 2,6-DMP dissolution. In the case of xIL=0.12, the slightly hydrogen-bonded water was fully destroyed and [C4C1im]Cl existed in the form of hydrated ion pairs. Interestingly, the maximum 2,6-DMP solubility (238.5 g/100 g) was achieved in this case. The interactions and microstructures of [C4C1im]Cl-water mixtures influenced the dissolution behavior of 2,6-DMP. 相似文献
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研究了耦合微腔结构的有机发光器件的光学和电致发光性能。通过将被动腔作为底部反射镜的方法,简化了耦合微腔的光学和发光性能的模拟,所得到的结果与实验符合得较好。在相同电流密度下与同样结构的普通OLED相比,耦合腔OLED的光谱强度在502 nm处增强了3.6倍,在550 nm处增强了5.6倍,光谱积分强度增加了0.5倍。普通OLED的最大电流效率和亮度是4.2 cd/A 和13 600 cd/m2。而耦合腔OLED则为7.0 cd/A 和 22 660 cd/m2。这种结构的器件出射光更集中于腔轴方向,有利于设计开发较高效率的有机激光器件。 相似文献
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