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81.
Zhongsheng Wang Chunhui Huang Fuyou Li Shuming Yang Shifu Weng Xiaoyi Fu Nianzu Wu Kurash Ibrahim Fengqin Liu Haijie Qian 《中国科学:化学(英文版)》2001,44(3):268-275
Self-assembled (SA) films (PMP, M = Ce3+ or Ce4+) of 3,4,9,10-perylenetetracarboxylic acid (PTA) on nanocrystalline TiO2 films with Ce3+ or Ce4+ as a bridge were fabricated and characterized with UV-Vis, IR, and XPS synchrotron radiation photoelectron spectroscopy (SRPES) which gave the HOMO energy levels for the SA films. It was shown that thin-layer sandwich-type solar cells based on these SA films possess good properties for photoelectric conversion. While PTA-loaded TiO2 electrode (P) generated 26.9% of incident monochromatic photon-to-electron conversion efficiency (IPCE), PMP-sensitized TiO2 electrodes yielded 55.8% and 39.1% for Ce4+ and Ce3+ respectively. PMP films can be considered as a kind of complexes whose HOMO energy levels were proved to be higher than that of film P, which is one of the major reasons for the increase in IPCE from film P to film PMP. 相似文献
82.
链型抽样方案综述(Ⅰ) 总被引:1,自引:1,他引:0
本文讨论了链型抽样方案(n,i)及其操作特性函数,并介绍了选取方案的方法。为制定链型抽样方案的检验标准及在实际中使用链型抽样方案提供理论依据 相似文献
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中国散裂中子源(Chinese Spallation Neutron Source, CSNS)靶站谱仪T0信号的高准确性和高可靠性是CSNS高效运行的重要条件之一。基于CPLD(Complex Programmable Logic Device)和PMC(Peripheral Mezzanine Card)子母板组合,设计了满足分布式架构的T0信号扇出设备,自主研制了24 V电平触发的中子斩波器专用触发信号接收插件;在1.6 GeV质子束首次打靶前,对T0信号延迟及信号调理做了优化。T0信号扇出设备接口信号灵活多变,具有较强的可维护性和可扩展性,已投入使用近三年,系统稳定可靠,为今后二期谱仪更高需求的T0信号扇出设备的研发积累了宝贵的建设经验。 相似文献
85.
Donggang Ran Hairui Xia Shangqian Sun Peng Zhao Fengqin Liu Zongcheng Ling Wenwei Ge Huaijin Zhang Jiyang Wang 《Crystal Research and Technology》2006,41(12):1189-1193
Barium tungstate (BaWO4) single crystal has been grown using Czochralski technique. It belongs to the scheelite structure, forming the space group I 41/a at room temperature and the primitive cell contains two molecular units. The polarized Raman spectra were recorded by a micro‐Raman spectrophotometer system in the backscattering geometry. All the observed Raman modes were assigned. The Raman mode at 924 cm–1, which belongs to the totally symmetrical Ag optical modes, has the strongest intensity and its linewidth is 4.6 cm–1. The infrared active lattice vibrations have been studied, eight optical modes were observed and assigned. The ultraviolet absorption edge is at 256 nm and the optical transparency range is up to 2500 nm at room temperature. The energy gap Eg of this crystal was obtained from the optical transmission spectra. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Letbe a sequence of real-valued randomvariables and be other random variables which are independentof the form sequence. Suppose that are pairwise generalized negativelyorthant dependent with heavy tails under the condition that areindependent or associated, some asymptotic formulas are established. 相似文献
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液—液相转移催化法合成芳氧基乙酰芳胺 总被引:6,自引:2,他引:6
N-(二芳基醚)酰胺和N-(2-噻唑基)芳氧基乙酰胺类化合物可用作除草剂,它们的经典合成方法由酰氧和胺在化学计算量的缚酸剂吡啶或三乙胺的存在下制得。亦可不加缚酸剂使羧酸与三氯化磷作用生成酰氯的同时紧接着与胺反应而合成。两种方法的产率都低,后一方法的反应条件还比较苛刻。 相似文献