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991.
SONG Hua-Can WEN Huan LIANG Dong SUN Yi-Feng 《有机化学》2003,23(Z1):411-412
It has attracted a lot of attentions to synthesize and investigate the behaviors of organic second-order nonlinear optical (NLO) materials. [1,2] We have ever reported that acridine derivatives ,[3] 4-substituted-benzylideneoxazol-5(4H)-one[4] and 4,4′-di-styryl-biphenyl derivatives[5] possess good second-order NLO properties. Coumarin derivatives are good organic optical materials and azobenzene derivatives possess a higher second-order nonlinear polarization values, however, there are few reports about the study on the synthetic method, optical behavior, especially,second-order NLO properties of 3-substitued-6-(substituted-phenylazo) coumarin derivatives. Therefore, a series of the following compounds were prepared in order to investigate their NLO behavior. 相似文献
992.
The kinetic characteristics of the concentrated Ⅴ(Ⅳ)/Ⅴ(Ⅴ) couple have been studied at a glassy carbon electrode in sulfuric acid using rotating-disc electrode and cyclic voltammetry. The kinetics of the Ⅴ(Ⅳ)/Ⅴ(Ⅴ) redox couple reaction was found to be electrochemically quasi-reversible with the slower kinetics for the Ⅴ(Ⅴ) reduction than that for the Ⅴ(Ⅳ) oxidation. And, dependence of diffusion coefficients and kinetic parameters of Ⅴ(Ⅳ) species on the Ⅴ(Ⅳ) and H2SO4 concentration was investigated. It is shown that the concentration of active species Ⅴ(Ⅳ) should be over 1 mol·L^-1 for the redox flow battery application. Further, with increasing the Ⅴ(Ⅳ) and H2SO4 concentration, the diffusion coefficients of Ⅴ(Ⅳ) were gradually reduced whereas its kinetics was improved considerably, especially in the case of Ⅴ(Ⅳ) and H2SO4 up to 2 and 4 mol·L^-1. 相似文献
993.
Electrophoretic deposition of nickel, iron and aluminum nanoparticles on carbon fibers 总被引:1,自引:0,他引:1
Kun Luo Nanlin Shi Hongtao Cong Chao Sun 《Journal of Solid State Electrochemistry》2006,10(12):1003-1007
The electrophoretic deposition (EPD) of nickel (Ni), iron (Fe) and aluminum (Al) nanoparticles fabricated by an active hydrogen plasma evaporation method on the surface of carbon fibers was investigated, which will allow the obtained composites to be applied as practical catalysts or electrodes. SEM observations show that the Ni nanoparticles can build up a thick EPD coating with some cracks on the surface of carbon fibers, and the analyses of X-ray diffraction (XRD) and BET specific surface area indicate that fine particles from the as-received Ni powders were finally deposited after the EPD process without crystal growth. The surface oxidation of Fe and Al nanoparticles takes serious effect on the EPD process and the morphology of the as-prepared coatings. 相似文献
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锌离子掺杂羟基磷灰石(HA)不仅影响HA的晶体结构和微观形貌,还影响材料的热稳定性和生物学性能.本文采用水热合成法制备了锌离子掺杂HA(Zn-HA)晶须,通过XRD、FTIR和SEM等测定和研究了Zn-HA的晶体结构、形成过程、结晶形貌和热稳定性.结果表明,Zn2+掺杂量<5;时,可获得单相Zn-HA晶须;当Zn2+掺量为5;时,合成产物中开始有少量的CaZn2(PO4)2·2H2O杂质相生成;当增加至8;时,开始有明显的Zn(PO3)2杂质峰出现.随水热合成温度的增加,溶液的OH-不断释放,伴随HA晶核的形成和生长,还有极少量的CaZn2(PO4)2·2H2O和Ca3(PO4)2杂质相,并通过溶解再沉淀生成Zn-HA.当Zn2+的掺杂量在0~8;时,随着Zn2+掺杂量的增加,样品的结晶度逐渐降低,晶格常数a值有所增加,c值基本不变.Zn2+掺杂HA晶须在>800℃的环境下热处理,Zn2+掺杂量的增加和热处理温度的改变都会促进HA晶须向β-TCP转化,形成双相磷酸钙. 相似文献
998.
QinFenSHI XiaoMeiWANG KeJunPAN WanLiJIANG DiJiangWEN XinBoWANG 《中国化学快报》2004,15(3):375-378
Three new naphthaline-type chromophores end-capped with different (p-substituted amino) styryl groups on the both sides (named as BPASN, BHMASN and BMASN) have been synthesized. Under excitation of 380nm, strong green light-emitting locating at 517nm with the fluorescence quantum yield of 0.88 in CH2Cl2 has been obtained.In the presence of β-cyclodextrin (β-CD), strong blue-emitting at 456nm in DMF was also recorded. 相似文献
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