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991.
JiangBinXIA FuYouLI ShuMingYANG ChunHuiHUANG 《中国化学快报》2004,15(5):619-622
Composite nanoporous electrode SnO2/TiO2 was fabricated for the dye sensitized solar cell (DSSC) with N3 (Cis-Ru). After introducing of TiO2, the open-circuit photovoltage (Voc) was higher than that of the pure SnO2 electrode, while short-circuit photocurrent (Isc) was varied with the ratio of the TiO2. Appropriate content of the TiO2 can be beneficial to the efficiency of the solar cell, and it gives negative impact on the composite electrode when the content of TiO2 is higher. 相似文献
992.
QiongCHENG TuZhiPENG XiaoBoHU CatherineF.YANG 《中国化学快报》2004,15(12):1473-1476
A novel fibroin modified electrode with ion recognition was reported. The membrane with isoelectric point of pH 4.5, was modified on graphite and carbon fiber electrodes. The pH-responsive ion recognition of the modified electrode was investigated by use of some neurocompounds. The fibroin carbon fiber electrode has been used for in-vivo determination. 相似文献
993.
HAOSan-cun FANLe-qing WUJi-huai HUANGYun-fang LINJian-ming 《高等学校化学研究》2004,20(2):205-209
A dye-sensitized nanocrystalline TiO2 solar cell(DYSC) was assembled, of which counter electrode was modified already by platinum, nickel and carbon. It was found that the DYSC had better photoelectric performance when the electrode was modified by platinum than by nickel and carbon. The influence of the incidence light wavelength on the incidence monochromatic photoelectric conversion effieieney(IPCE) was investigated.The result shows that the IPCE mainly depends on the short-circuit current density(Isc) of a DYSC, and the IPCE reaches 48.32% under the irradiation with the wavelength of 560 nm when the counter electrode of a DYSC was modified by platinum. The influence of incident light intensity on the photoelectric properties of a DYSC was also investigated. It was found that the Isc and open-circuit voltage(Voc) increased and the fill factor(ff) of the DYSC decreased with the increase of the incident light intensity. 相似文献
994.
CHENTao AnneNeville YUANMing-dong 《高等学校化学研究》2004,20(4):381-385
Magnesium ions, which exist in formation water and injection water under downhole conditions in the oil and gas production industry, are a key determinant in the CaCO3 scale formation. Many studies have focused their attention on the effect of magnesium on the kinetics, the morphology and the content of Mg in the Ca-CO3 scale. Little attention has been paid to the effect of Mg^2 on the initial stages of CaCO3 formation on a metal surface. In this study, an electrochemical technique was used to study the influence of Mg^2 on the ini-tial stages of CaCO3 scale formed on a metal surface. With this electrochemical technique, the reduction of the dissolved oxygen in an analysis solution is considered on the surface of a rotating disk electrode (RDE) un-der potentiostatic control. The rate of oxygen reduction on the surface of the RDE enables the extent of sur-face coverage of scale to be assessed. With this electrochemical technique, a new insight into the effect of Mg^2 on CaCO3 scale formed on a metal surface is given. 相似文献
995.
IntroductionAmperometricbiosensorofhydrogenperoxideisofpracticalimportancebecauseofitswideapplicationsinchemical,biological,clinical,environmentalandmanyotherfields.Forimprovementofsensor抯quality,vari-ouskindsofchemicalmodificationmethodshavebeendevelopedforreducingredoxoverpotentialsofH2O2atelectrodesurfaces,increasingthedetectionsensitivity,linearrange,stabilityandlivetime.Ithasbeenshownthattheuseofsub-micrometersizedmetalparticlessuchasPt-blackcansignificantlyimprovethequalityofthebiosens… 相似文献
996.
Introduction Overall exposure to lead is of public health concern because of several hazardous effects that may occur to human beings. Lead poisoning may provoke irritability, anorexia, malaise and headache. Intoxication progress may lead to attacks of abdominal pain until coma and death.1 The determination of trace lead in variety of en-vironmental samples is of great importance since lead is recognized as a cumulative poison to animals and hu-mans. There is a constant demand for improved an… 相似文献
997.
998.
在Tris-NaC1*(pH=7.2)缓冲溶液中,应用循环伏安法,微分脉冲伏安法、旋转圆盘电极实验、交流阻抗法及其数据模拟等技术研究了Cu(phen)2 25(phcn=1.10-邻菲咯啉)与6-巯基嘌呤(6-MP)的相互作用.结果显示.Cu(phen)2 2MP与6-MP无论在扩散控制过程或电化学控制过程都发生了相互作用.Cu(phen)2 2及其与6-MP的作用产物于铂电极上均呈现一对氧化还原峰,但后者呈现的氧化还原峰负移.峰电流减小.交流阻抗结果显示,无论6-MP存在与否,Cu(phen)2 2在交流阻抗谱上均呈现两个清晰的电容弧,但当6-MP存在时,电化学反应电阻和电化学吸脱附电阻均增大.Cu(phen)2 2在不同转速下的阻抗拟合结果显示.随转速增大.电化学反应电阻和电化学吸脱附电阻均减小.双电层电容呈增大趋势,而吸脱附电容呈减小趋势:当6-MP存在时.仍然呈现此变化规律. 相似文献
999.
采用循环伏安法(CV),由β-环糊精(β-CD)单体在玻碳电极(GCE)表面电聚合制得聚β-CD膜修饰电极(β-CD/GCE)。实验表明,β-CD/GCE对Cu2+具有明显的电催化作用,在pH=5.85的磷酸盐缓冲溶液(PBS)中,Cu2+浓度与其峰电流在4.01×10-4~1.05×10-7 mol·L-1范围内呈良好的线性关系,线性方程为:ip=-1.975c-1.336×10-4(i:A,c:mol·L-1),相关系数R=0.9981,检出限(S/N=3)为5.03×10-8mol·L-1。方法应用于实际样品测定,回收率在98.0%~103%之间。 相似文献
1000.