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991.
双溶剂浸渍法制备VOX/MCF催化剂及丙烷选择氧化 总被引:1,自引:0,他引:1
采用双溶剂法制备了负载型氧化钒类催化剂(VOx/MCF),N2物理吸附、X射线衍射、透射电镜、拉曼光谱、程序升温脱附、程序升温还原等系统研究了催化剂的物化性质并测试了其在丙烷选择氧化反应中的催化性能.结果表明,由双溶剂法制备的VOx/MCF催化剂具有较好的催化活性,且在氧化钒负载量基本一致的前提下,双溶剂法制备的VOx/MCF催化剂比普通浸渍法制备的VOx/MCF具有更高的催化活性,这与双溶剂法的制备过程可以使得钒物种尽可能进入载体内表面,有利于氧化钒的较好分散有关,而高度分散的氧化钒物种,正是丙烷选择氧化反应的活性中心. 相似文献
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Yuanhua Liu Najun Li Xuewei Xia Jianfeng Ge Qingfeng Xu Jianmei Lu 《European Polymer Journal》2011,47(5):1160-1167
Two styrene/maleimiade copolymers with pendant azobenzene chromophores, poly(styrene-1-(4-phenylazo-phenyl)-pyrrole-2,5-dione) (PS-DP) and poly((4-vinyl-benzyl)-9H-carbazole-1-(4-phenylazo-phenyl)-pyrrole-2,5-dione) (PVCz-DP), were synthesized. The polymeric memory devices based on each of the two polymer films (ITO/Polymer/Al) show similar rewritable flash memory behaviors but different transition voltages. By introduction of carbazole groups in the polymer side chains, the voltage difference from OFF to ON state of ITO/PVCz-DP/Al is reduced obviously in comparison with that of ITO/PS-DP/Al, which is beneficial to the protection of devices. Both ITO/PS-DP/Al and ITO/PVCz-DP/Al show high stability under a constant stress or continuous read pulses voltage of 1.0 V. The memory mechanism is governed by space-charge limited conduction (SCLC) on the basis of the I–V curves of these fabricated memory devices. With excellent flash memory characteristics and simple processability, the memory devices fabricated with these two styrene/maleimiade copolymers have potential applications for the future electronic memory devices. 相似文献
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A novel temperature controlled ionic liquid dispersive liquid phase microextraction(TCIL-DLPME) coupled with rapid resolution liquid chromatography-electrospray tandem mass spectrometry(RRLC-ESI-MS-MS) has been developed for the enrichment and determination of three hexabromocyclododecane diastereomers(HBCDs) in water samples.Green solvent ionic liquid(IL) was used as extraction solvent instead of toxic organic solvents.This technique also avoided the usage of dispersive solvent.Some important parameters that might affect the extraction efficiency were optimized.Under the optimum conditions,good linear relationship,sensitivity and reproducibility were obtained.All the limits of detection for the three diastereomers were 0.1 ng/ mL.The linear range was obtained in the range of 1-100 ng/mL for the total amount of three HBCD diastereomers.It was satisfactory to analyze real environmental water samples with the recoveries ranging from 77.2%to 99.3%.The main advantage of the method is toxic organic solvent-free. 相似文献
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Shi XH Wang Z Xia Y Ye TH Deng M Xu YZ Wei YQ Yu LT 《Molecules (Basel, Switzerland)》2012,17(4):3933-3944
A series of novel benzothiazole-2-thiol derivatives were synthesized and their structures determined by 1H-NMR, 13C-NMR and HRMS (ESI). The effects of all compounds on a panel of different types of human cancer cell lines were investigated. Among them, pyridinyl-2-amine linked benzothiazole-2-thiol compounds 7d, 7e, 7f and 7i exhibited potent and broad-spectrum inhibitory activities. Compound 7e displayed the most potent anticancer activity on SKRB-3 (IC(50) = 1.2 nM), SW620 (IC(50) = 4.3 nM), A549 (IC(50) = 44 nM) and HepG2 (IC(50) = 48 nM) and was found to induce apoptosis in HepG2 cancer cells. 相似文献