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811.
硫代乙酰胺体系电沉积法制备CdS纳米膜 总被引:6,自引:0,他引:6
The film of surface active agents spread out on the surface of the electrolyte of Thioacetamide and cadmium chloride. CdS nanofilm was deposited at the interface of surface active agents and electrolyt by the method of electrodeposition. The optimal conditions on which the nanofilm was prepared of the least crystals and uniform particles could be attained via analytical results of L16(45) orthogonal experiments. The optimal conditions: castor oil/hexadecanoll 0.06 mL·cm-2,CdCl2/CH3CSNH2 4 mmol·L-1, cell voltage 5 V, electrodeposition temperature 15 ℃. The effects on the grain size of temperature, surface-active agent, electrodyte concentration, cell voltage and pH become smaller in the series. If the temperature was high, the movement of molecules of surface-active agent and electrodyte would be faster, thus the preparation of the film would be difficult. The grain size of thinfilm varied with the surface-active agents, however, when the amount of surface-active agents reached a certain value, the grain size would remain unchanged. The higher the electrodyte concentration, the larger the grain size of nanofilm. The surface forms were changed at the same time. If the pH of the electrodyte was higher or lower, nanofilm could not be prepared successfully, thus the pH range should be is 3~6. SEM image of the nanofilm shows the occurance of dendrite. The sucessful preparation of nanofilm is closely related to the nature of surface activre agent due to the nanofilm growth mechanism. 相似文献
812.
Zhong Jie ZOU Yue Sheng DONG Jun Shan YANG 《中国化学快报》2005,16(11):1484-1486
A new β-carboline alkaloid, 4-(9H-β-carbolin-1-yl)-4-oxobutyric acid and a new derivate of isoferulic acid, (E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester, were isolated from the roots of Anemone altaica. Their structures were determined on the basis of spectral data. 相似文献
813.
1mTRODUCT1ONBinuclearcoppercomplexesareimportantnotonlyincoordinationchemistryandmagnetostructuralstudiesbutalsoinpracticalapplication.tliInanattempttoseekthedisPersionandemulationreagentsofCWM(themixtureofcoalandwater),thetitlecomP0undwassynthesizedbyanoxidativepreparationmethodt2i,whosesynthesisandstructurearedifferentfromthosedescribedbyWangetoft3i.Here,0nlythesynthesisandstructureofthetitlecomP0undarereportedandthestudiesofitsappli-cationareinprogress.2EXPERIMENTAL2.1Preparati0n… 相似文献
814.
815.
The influences of UV light irradiation (313 nm) and diffused daylight on the polymerization of methyl acrylate initiated by the ceric ammonium nitrate without any reducing agent have been studied both in aqueous nitric acid and in pure water. The rate of polymerization was found to be accelerated and the overall activation energy and the induction time were found to be decreased sharply by the UV light irradiation. Under UV light, the rate of polymerization is 8 times as high as the rate in dark. The rate of polymerization was found to attain a maximum with the increase of nitric acid concentration and the rate of polymerization became less sensitive to UV light in the presence of nitric acid whereas the induction period reduced outstandingly. Based on the experimental results, the mechanism is proposed. 相似文献
816.
原子吸收光谱法测定拉伸断口铬镍钼钛钢样品中主成分 总被引:4,自引:0,他引:4
研究了毫克级铬镍钼风样品中主成分镍的火焰原子吸收光谱法(FAAS法)和铬、钼、钒、钛、铝的塞曼恒温平台石墨炉原子吸收光谱法(ZSTPF-AAS法)。采用了微波溶样技术作为防污染样品预处理技术,采用石墨管硅涂层改进技术提高了仪器的测试精度。其中铬、镍、钼、钒、钛、铝的相对标准偏差分别为2.7%,0.97%,8.6%,7.3%,1.7%,7.3%。其加标回收率分别为96.5%,97%,96.7%,93%,98%,91%。通过分析,发现在较低温度下铬镍钼钛钢断面上有轻微的钼偏析现象,可能是拉伸断裂的主要化学影响因素。 相似文献
817.
818.
用激光光解-激光诱导荧光方法研究了室温下(T=293K)HCF(X%A′)自由基与SO2分子的反应动力学.实验中1HCF(X%A′)自由基是由213nm激光光解HCFBr2产生的,用激光诱导荧光(LIF)检测HCF(X%A′)自由基的相对浓度随着11反应时间的变化,得到此反应的二级反应速率常数为:k=(1.81±0.15)×10-12cm3?molecule-1?s-1,体系总压为1862Pa.高精度理论计算表明,HCF(X%A′)和SO2分子反应的机理是典型的加成-消除反应.我们运用RRKM-TST理论计算了1此二级反应速率常数的温度效应和压力效应,计算结果和室温下测定的二级反应速率常数符合得较好. 相似文献
819.
ChangLuSHAO HongYuGUAN ShangBinWEN BinCHEN XingHuaYANG JianGONG YiChunLIU 《中国化学快报》2004,15(4):492-494
Thin PVA/cobalt acetate composite fibers were prepared by using sol-gel processing and electrospinning technique.After calcination of the above precursor fibers,Co3O4 nanofibers with a diameter of 50-150 nm could be successfully obtained.The fibers were characterized by SEM,FT-IR,WAXD,respectively. 相似文献
820.
采用聚乙烯醇与环氧乙烷非均相加合反应合成了不同环氧乙烷结合量的羟乙基化聚乙烯醇(HEPVA).在通过13C-NMR和IR对产物进行表征的基础上,讨论了反应与PVA空间立构性及结晶性间的关系,证明了HEPVA中聚氧乙烯链的存在,且其含量增长速率随反应深度的增加而增大. 相似文献