共查询到19条相似文献,搜索用时 78 毫秒
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应用循环伏安法、微分脉冲伏安法对多菌灵在破碳电极上的电化学行为及其测定进行了研究。在pH=9.0的2mol/L NH3-NH4Cl底液中,对其进行循环伏安扫描,发现于0.61V(vs.Ag/AgCl)产生一灵敏的氧化峰。微分脉冲伏安法殉菌灵的检测限为4×10^-8mol/L。多菌灵的浓度在5.0×10^-7 ̄1.0×10^-5mol/L间与微分脉冲伏安峰电流呈线性关系(r=0.9942)。对于1× 相似文献
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采用循环伏安法和差分脉冲伏安法研究了咖啡酸苯乙酯(CAPE)在玻碳电极表面上的电化学行为。在0.05 mol.dm-3磷酸盐缓冲溶液(PBS,pH=7.6)中,CAPE在0.229 V和0.214 V处呈现一对明显的氧化还原峰。考察了溶液pH值和扫描速率等因素对CAPE电化学行为的影响,结果表明,电化学过程中CAPE的电子转移数为2,参与反应的质子数也为2,且为吸附控制过程。在0.05 mol.dm-3磷酸盐缓冲溶液(PBS,pH=7.6)中,CAPE的氧化峰电流与其浓度在0.34~3.40μmol.dm-3范围内成线性关系,其响应灵敏度为0.88μA/μmol.dm-3,检出限为60 nmol.dm-3(S/N=3)。本研究建立了一种简单、快速、可灵敏测定CAPE的方法。同时对CAPE在玻碳电极上的电化学行为进行了较为详细的研究。 相似文献
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将氧化石墨烯悬浮液(1g·L~(-1))10μL滴涂于玻碳电极表面,烘干后,在0.10mol·L~(-1)的KH_2PO_4溶液中于-0.9V还原600s制备了氧化石墨烯修饰玻碳电极,用扫描电子显微镜、透射电子显微镜和电化学方法对修饰电极进行了表征。用差分脉冲伏安法研究了百草枯在氧化石墨烯修饰电极上的电化学行为,发现此修饰电极对百草枯的还原有明显的电催化作用。百草枯在pH 7.5的磷酸盐缓冲溶液中,在氧化石墨烯修饰电极上产生催化还原反应,在差分脉冲伏安曲线上先后在-0.6,-0.1V处出现2个还原峰。因后者与底液的还原峰重叠,故测定中采用-0.6V处的还原峰电流为测量值。经试验,百草枯在修饰电极上的富集电位为-0.6V,富集时间为200s,选用的扫描速率为50 mV·s~(-1)。在最佳试验条件下百草枯浓度在9.00×10~(-7)~1.00×10~(-5) mol·L~(-1)和1.00×10~(-5)~5.00×10~(-5) mol·L~(-1)内与其在-0.6V处的还原峰电流呈线性关系,检出限(3s/k)为1.64×10~(-7) mol·L~(-1)。方法应用于农药中百草枯含量的测定,测定值与标示值相符,对土壤样品进行加标回收试验,回收率在89.5%~114%之间。 相似文献
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Peter M.A. Sherwood 《Trends in analytical chemistry : TRAC》1984,3(5):121-125
Surface analysis methods are becoming increasingly important in the understanding of electrochemical systems. They provide complimentary information to that provided by electrochemical studies. 相似文献
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炔雌醇,又名乙炔雌二醇(Ethinylestradiol,EE),是一种雌激素.本文采用了现代电化学分析方法系统研究了炔雌醇在玻碳电极上的电化学行为.实验表明炔雌醇在玻碳电极上的氧化是不可逆过程,在不同pH值介质中,在玻碳电极上都有一定的吸附性.实验研究了在不同pH值条件下炔雌醇的各种电化学性质,并寻找到在不同条件下的定量方法,对实际样品进行了测定. 相似文献
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《Journal of Analytical Chemistry》2011,66(10):993
Critics and Bibliography
Journal on drug analysis 相似文献15.
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L. Nei 《Fresenius' Journal of Analytical Chemistry》2000,367(5):436-439
Cu-rich Cu-Ni alloys (containing 70–90% Cu) are shown to be excellent indicator electrode materials for voltammetric measurements
at cathodic potentials. These electrodes have been characterised using a variety of methods: rotating disk voltammetry, amperometric
measurements and sono-ring-disk voltammetry. The mechanism of electrochemical oxygen reduction at the Ni-30Cu alloy has been
established. The results are compared with the surface study results.
Received: 2 December 1999 / Revised: 17 February 2000 / Accepted: 25 February 2000 相似文献
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Lars Kryger 《Analytica chimica acta》1981,133(4):591-602
The advantages of incorporating digital computers in devices for electrochemical trace elemental analysis are discussed on the basis of examples from the literature. Apart from easing data interpretation, the digital computer may control and monitor electrode processes at a high interaction frequency. For elements undergoing reversible electrode reactions, the resolution and sensitivity of electrochemical techniques can be improved by such rapid real-time interaction. Moreover, for quasi-reversible systems, the application of computerized broad-band potential excitation and simultaneous monitoring of broad band relaxation signals, permits rapid extraction of analytical information from data which represent the electrode process more accurately than do traditional single-frequency a.c. polarographic data. 相似文献
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V. V. Slepushkin Yu. V. Rublinetskaya B. M. Stifatov 《Journal of Analytical Chemistry》2005,60(2):103-106
A review of advances in local electrochemical analysis is presented.Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 2, 2005, pp. 120–123. Original Russian Text Copyright © 2005 by Slepushkin, Rublinetskaya, Stifatov. 相似文献