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In this paper, a comparison viral made between the two results of determining Pb, Cd, Cu and Zn in seawater by direct current (tripping voltammetry (DCS) with rotating glass carbon electrode and by differential pulse stripping voltammetry (DPS) with hanging mercury drop electrode (HMDE). By DCS, the range of linear calibration curves obtained was 4×10-3 M-2×10-7M for Cu, Zn and Cd, and 4× 10-9M-2×10-3M for Pb. By using DPS, the range of linear calibration curve was as follows: Cu 0.65-1.9 ppb; Pb 1.0-10 ppb; Zn 0.65-2.0 ppb; Cd 0.02-0.14 ppb. It was found that DCS could be used for determining Pb, Cu, Zn in coastal waters, but it is necessary to add gallium ion to it to eliminate the interference of Cu-Zn inter-metallic compound for determining Zn. The DPS is better for determinig Cd. 相似文献
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本文提出采用悬汞电极示差脉冲阳极溶出伏安法和导数技术直接同时一次连测海水中Zn、Cd、Pb、Cu及Bi,研究了在本实验条件下Cu是否干扰Zn的测定,本方法的精密度和准确度均好,测定步骤简便快速,只需调海水的pH为2.5,电解富集10分钟就能测定近岸海水中这五种元素的存在含量,五种元素的单份海水测定约需25分钟。 相似文献
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海水中溶解镉的浓度范围一般在0.01-0.6微克/升之间[1].镉的污染毒性是众所周知的,研究痕量元素镉在海洋食物链中的转移变化过程,对人们研究污染物在海洋的扩散以及海洋环境的自净能力均有积极意义。近年来,国内出现了不少各有特色的用于水质测定的较好的阳极溶出伏安法[2,3],但直接测定海水中痕量镉均有困难。 相似文献
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DIRECT AND SIMULTANEOUS DETERMINATION OF Zn, Cd, Pb, Cu and Bi IN SEAWATER BY DERIVATIVE-VOLTAMMETRY
吕荣辉 《海洋学报(英文版)》1985,4(4):557-563
This paper suggests direct and simultaneous determinations of the reducible species of Zn, Cd, Pb, Cu and Bi in seawater made by the derivative-differential pulse anodic stripping voltammetry with a hung mercury drop electrode. The influence of Cu on the determination of Zn in this experiment condition has been studied, of which both the accuracy and precision are satisfactory. The procedure of determination is so quick, simple and convenient that the background concentration of these five elements in coastal seawaters can be determined only by adjusting the acidity of seawater to pH 2.5 and by taking 10-minutes plating time. Actual measurement time of these five elements for every sample is approximately 25 min. 相似文献
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An analytical method is proposed for the direct determination of Cd in seawater by differential pulse anodic stripping voltammetry and the derivative technique with a hanging mercury drop electrode. The process of determination is quick, simple and convenient. The concentration of Cd in seawater is only determined by adjusting the acidity of seawater to pH 2 and by taking three minutes' plating time. Sensitivity of the method is about 1×10-10M, and accuracy of that satisfactory. Relative standard deviation is about 12% when the concentration of Cd in seawater is approximately 0.04 ppb. A good agreement was obtained by a standard curve and a standard addition technique respectively from determining Cd in the same seawater. Actual measurement time per sample is about 10 min. 相似文献
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