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991.
992.
水蒸气沉淀法制备SiO2/偏氟乙烯-六氟丙烯共聚物复合微孔型聚合物电解质的研究 总被引:4,自引:0,他引:4
用水蒸气沉淀法制备了SiO2 偏氟乙烯 六氟丙烯共聚物 [P(VDF HFP) ]复合微孔型聚合物电解质 ,并研究了纳米SiO2 的加入对微孔结构及复合微孔型聚合物电解质性能的影响 .SEM观察发现当纳米SiO2 的添加量大于 0 1倍聚合物质量时 ,可以在微孔中观察到纳米粒子的严重团聚现象 .电导率的测量表明添加 0 0 5倍聚合物质量的纳米SiO2 后 ,微孔型聚合物电解质的电导率有明显提高 ,但进一步增大添加量后 ,电导率有所下降 .另外 ,实验发现添加纳米SiO2 可以明显提高微孔型聚合物电解质与锂金属电极之间的界面稳定性 ,特别是添加量为 0 0 5倍聚合物质量时的效果良好 . 相似文献
993.
研究了甲醇在温度301K、压力169.2~713.8MPa下的拉曼特征。其中νCH区伸缩振动随压力增大,拉曼位移向高频方向移动,说明C-H键键能在增大;而νOH区伸缩振动随压力增大,拉曼位移则向低频方向移动,表明氢键对O-H基团的影响大于压力效应。另外,O-H伸缩振动峰的相对面积随压力的增大而减小,说明对C-H键而言,O-H键总强度是减弱的。 相似文献
994.
Li Z Du AJ Sun Q Aljada M Cheng LN Riley MJ Zhu ZH Cheng ZX Wang XL Hall J Krausz E Qiao SZ Smith SC Lu GQ 《Chemical communications (Cambridge, England)》2011,47(43):11894-11896
Co(2+)-doped CdSe colloidal nanowires with tunable size and dopant concentration have been prepared by a solution-liquid-solid (SLS) approach for the first time. These doped nanowires exhibit anomalous photoluminescence temperature dependence in comparison with undoped nanowires. 相似文献
995.
Concise total synthesis of (-)-8-epigrosheimin 总被引:1,自引:0,他引:1
A highly efficient route was developed to synthesize (-)-8-epigrosheimin in four steps from aldehyde 2 based on a substrate-controlled method. The key steps of the synthesis included (1) a stereo- and regioselective allylation addition, (2) an intramolecular translactonization, and (3) an aldehyde-ene cyclization. 相似文献
996.
Out of the frame: A marker study using gold frames was designed to reveal that silver nanoplates undergo a shape transition during their seeded growth from triangular to circular to hexagonal plates before ultimately returning to triangular structures with an orientation 180° relative to that of the original triangular seeds (see picture, the original gold triangular frame is visible at the center of the silver nanoplate). 相似文献
997.
Bingbing Sun Li Qi Yaping Li Juan Qiao Minglin Wang 《Journal of separation science》2013,36(21-22):3629-3634
A new and simple open‐tubular CEC (OT‐CEC) method with a novel diblock copolymer poly(butyl methacrylate)71‐block‐poly(glycidyl methacrylate)9 as the coating based on its self‐assembled properties has been developed. Compared with the bare capillary, this coating could act as a surfactant and improve the separation efficiency of aromatic amines. Meanwhile, the effects of pH value, buffer concentration, and the copolymer block ratio on the separation efficiencies were investigated in detail. It has been found that the three tested aromatic amines could be baseline separated by the OT‐CEC method with the cooperation of SDS. The proposed OT‐CEC method showed good repeatability with RSDs <3.2% for testing the EOF. Moreover, it was also well validated by satisfactory linearity and favorable recovery, which ensured its successful application in the separation of aromatic amines in nail polish samples. The results revealed the potential applicability of the OT‐CEC method in cosmetic analysis. 相似文献
998.
Shi-Xia Li Gui-Qiu Li Sheng-Zhi Zhao Xiao-Mei Wang Ke-Jian Yang De-Chun Li Wen-Chao Qiao Hai-Juan Zhang Tian-Li Feng Hong-Wei Chu 《Optical and Quantum Electronics》2014,46(9):1179-1186
By using GaAs wafer as the saturable absorber, the laser-diode pumped passively Q-switched composite Nd:YVO \(_{4}\) laser has been successfully demonstrated. For this passively Q-switched operation, the average output power obtained is as high as 846 mW at the incident pump power of 5.31 W, while the pulse duration is as short as 14.5 ns. The largest single-pulse energy of 2.49 \(\upmu \) J and the highest peak power of 166 W are obtained. The GaAs saturable absorber with thickness of 400 \(\upmu \) m has shown more excellent laser performance comparing with 700 \(\upmu \) m thick GaAs. 相似文献
999.
基于LCTF的多光谱面阵CCD相机的辐射定标 总被引:4,自引:0,他引:4
基于液晶可调谐滤光片(LCTF)的多光谱面阵CCD相机是一种新型的多(高)光谱成像系统,它利用液晶的电控双折射效应和偏振光的干涉原理,在面阵CCD上记录任意一个波长的图像信息.由于LCTF和帧转移型面阵CCD工作方式的特殊性,普通的定标方法不能满足遥感应用的精度需求.提出用积分球+标准探测器的定标系统对相机进行性能检测... 相似文献
1000.
This paper proposes a corrected method of distorted image based on adaptive control. First, the adaptive control relationship of pixel point positions between distorted image and its corrected image is given by using polynomial fitting, thus control point pairs between the distorted image and its corrected image are found. Secondly, the value of both image distortion centre and polynomial coefficient is obtained with least square method, thus the relationship of each control point pairs is deduced. In the course of distortion image processing, the gray value of the corrected image is changed into integer with bilinear interpolation. Finally, the experiments are performed to correct two distorted printed circuit board images. The results are perfect and the mean square errors of residual error are tiny. 相似文献