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崔春国 《化学学报》1983,41(10):927-933
A method of simultaneous determination of copper (II), lead (II) and cadmium (II) in sulphuric acid-iocide ion medium was established by derivative anodic stripping voltammetry (DASV) on the gold electrode. The peak theights of lead and cadmium were increased by enhancement effect of iodide ion and the peaks of bismuth and copper were well formed and completely resolved on gold electrode in the presence of iodide ion, therefore peak of copper is not affected by bismuth. The sensitivities for copper, lead and cadmium were very high and their peak potentials in the stripping voltammogram were +0.25, -0.2 and -0.27 volt, respectively. The dependence of peak height of these elemets on their concentrations was linear. The detection limits for copper, lead and cadmium were 0.2 0.2 and 0.05 ppb, respectively. We have further studied the electrode process by means of triangle cyclic voltammetry and proved that he electrode reaction of copper is reversible, and that the reversibility of electrode reactions of lead and cadmium is not good.  相似文献   

4.
银微盘电极上碘离子的示差脉冲溶出伏安法   总被引:6,自引:0,他引:6  
方宾  方惠群 《分析化学》1997,25(1):59-62
基于I能与Ag生成难溶出化合物特性,在银微盘电极上研究了I的示差脉冲溶出伏安法(DPSV)。该法不需镀汞,不要搅拌,可在较稀稀的支持电解质溶液中实施。于0.08mol/LHAc-NaC及0.01mol/LEDTA介质中,能检出1.00×10^-8mol/L的I,I的浓度为5.00×10^-6--1.20×10^-8mol/L范围与峰电流有良好的线性关系。该法用于自来水中I的测定,相对偏差为4.3%  相似文献   

5.
离子缔合富集阴极溶出伏安法测定痕量碘:Ⅰ....   总被引:5,自引:0,他引:5  
  相似文献   

6.
微分脉冲阳极溶出伏安法测定碘离子   总被引:9,自引:0,他引:9  
基于I-能被氧化生成IO3-的特性,以铂球电极为工作电极,研究了微分脉冲阳极溶出伏安法(DPAS)测定碘离子.由于产物IO3-在电极上有吸附,因而在+1.3V电清洗120s.在pH=4的0.1mol/LKH2PO4-K2HPO4缓冲溶液底液中,能检测出5.00×10-7mol/L的I-,在5.00×10-71.50×10-5mol/L范围内I-的浓度与峰电流有良好的线性关系.该方法用于海带、食用碘盐中碘的测定,取得了较好的结果.  相似文献   

7.
邵勇  王曙 《分析化学》1997,25(7):780-783
采用自制的简易电解池,以圆盘旋转玻碳电极为工作电极,用于阳极溶出伏安法改换溶出介质的可行性研究。以同时测定Cu(Ⅱ),Sb(Ⅲ)为例,试验了改换溶出介质的条件。此方法用于矿样中铜和锑的同时测定,结果满意。  相似文献   

8.
研究了铜膜电极代替汞膜电极测定重金属铋的差分脉冲溶出伏安法。实验了同位镀膜法测定铋的条件。在最佳实验条件下,Bi3+浓度在5×10-8~2×10-5mol/L范围内,其溶出峰峰高与浓度呈线性关系,检出限达到1×10-8mol/L。测定了一些药物中铋的含量,结果准确。  相似文献   

9.
本文以十六烷基三甲溴化铵阳离子(R~+)为离子缔合剂,选择适当电位,使I~-经电极氧化生成I_2,与Br~-络合成I_2Br~-,再缔合为RI_2Br沉淀,富集于玻碳电极上,随后以直流电压线性扫描阴极溶出,方法灵敏,选择性好,用于测定生物样品中碘含量,结果满意。  相似文献   

10.
水中痕量氯化物的阳极溶出伏安法   总被引:1,自引:0,他引:1  
  相似文献   

11.
《Analytical letters》2012,45(7):1411-1420
Abstract

Cadmium in the presence of 0.04 M NaCl as the electrolyte was determined using stripping voltammetry with superimposed constant amplitude pulses of negative polarity (SVPNP) or positive polarity (SVPPP), and differential pulses stripping voltammetry using rotating disc glass carbon electrode (RDGCE). The SVPNP was found to give the greatest sensitivity. The anodic peak was obtained at potential ?850 to ?795 mV due to the oxidation of cadmium to cadmium(II). Linear calibration curves were obtained in the concentration range between 1.5×10?9–2×10?10 M. The relative standard deviation is 4.25% at very low concentration of 2×10?10 M. This method was successfully applied to the determination of cadmium in some foodstuffs (wheat and its products, vegetables) after acid digestion.  相似文献   

12.
An electrochemical anodic stripping procedure for ultra-trace assay of xanthine in Cu2+ solution at a glassy carbon electrode (GCE) is described. Cyclic voltammetry was used to characterize the nature of the process taking place at the GCE. The anodic stripping response in the presence of Cu2+, at 150mV (peak I) and 600mV (peak II), is evaluated with respect to various experimental and instrumental conditions. Voltammetric studies show that the mechanism of the overall reaction is similar to that of the oxidation of purine derivatives at a pyrolytic graphite electrode. It is found that the copper metal deposited onto the GCE was oxidized to Cu+ at around –180mV vs. Ag/AgCl and the generated Cu+ reacted with xanthine to accumulate on the GCE as an insoluble compound. The Cu+-xanthine compound accumulated on the GCE was redissolved by the oxidation of Cu+ to Cu2+ at ca. 150mV, and the concentration of xanthine in the vicinity of the GCE increased. The results enabled us to use the measurement of the oxidation peak current as the basis of a simple, accurate and rapid method of determining xanthine within a concentration range of 19.9 to 166nM for peak (I) and 0.24 to 17.2µM for peak (II). Promising results were obtained for xanthine determination by using an external mixing step prior to stripping measurements, which yielded a detection limit of 0.138µgL–1 (9.1×10–10M) xanthine. The effect of some interferences (e.g. purine compounds, amino acids and some metal ions) was considered.  相似文献   

13.
用微分脉冲阳极溶出伏安法同时测定癌症病人血液中的锌、镉、铅和铜,以为癌症与这4种微量元素在血液中含量的相关性研究提供实验数据;癌症病人血液用硝酸-高氯酸消化,消化后的白色固体加水溶解,以0.100mol/L硫酸铵为底液,在三电极体系中进行测定,以峰电位定性,峰电流定量;用该法测定了3种癌症病人血液中的锌、镉、铅和铜,相对标准偏差为2.9%—3.3%(n=6),加标回收率为98%—110%;该法不用除氧、干扰少、分辨率好、准确度高,适用于临床血液中锌、镉、铅和铜的测定和研究。  相似文献   

14.
《Analytical letters》2012,45(1-2):89-98
Abstract

An A.S.V. method for determination of mercury in ultrapure gallium has been developed. The procedure is very simple and allows a sensitivity high enough to verify the highest purity level of Ga as concerns Hg traces (i.e. 1×10?5 % Hg in Ga by weight).

The above method was applied to some samples of gallium used in this laboratory.  相似文献   

15.
Nafion修饰金电极阳极溶出伏安法测定痕量碲   总被引:4,自引:0,他引:4  
本文用Nafion修饰金盘电极,在0.04mol/LLiCl和PH2的H2SO4底液中,阳极溶出伏安法测定痕量碲,研究了富集溶出过程的特性和优化条件,碲浓度在0.2-15ng/mL范围内与溶出峰电流呈良好的线性关系。本法灵敏度高,选择性好,用于测定小麦粉和玉米粉中痕量碲,测定标准偏差小于0.07μg/g,与ICP测定结果比较其相对误差小于16%。  相似文献   

16.
倪永年 Kokot  S 《分析化学》1994,22(5):431-435
本文利用微分脉冲阳极溶出伏安法对微量铜、锑、铋混合溶液进行同进分析,实验在盐酸-氯化钠介质中进行,悬汞电极作工作电极,在-400mV处富集电解5min,然后由-400mV向0V作微分脉冲溶出伏安扫描,扫描速度为2mV/s,脉冲振幅为40mV,由于计算机采集溶出伏安数据后采用偏最小二乘法计算并建立数学模型,然后据此模型对未知溶液进行定量分析,获得了较好的结果。  相似文献   

17.
The voltammetric performance of an in situ plated antimony film screen-printed carbon electrode in hydrochloric acid, acetate buffer, and tartrate buffer was evaluated for the detection of copper(II) with differential pulse anodic stripping voltammetry. The tartrate buffer was superior, providing high sensitivity and good separation of copper and antimony stripping peaks. The analytical conditions for the determination of copper(II) were optimized. The detection limit was estimated to be 0.14?µg?L?1 copper(II) and the relative standard deviation for 2.5?µg?L?1 copper(II) was 3%. The applicability of the method was illustrated by the analysis of soil conditioner samples.  相似文献   

18.
碳纳米管修饰电极差示脉冲阳极溶出伏安法测定腺嘌呤   总被引:7,自引:0,他引:7  
在HAc NaAc缓冲溶液中,玻碳电极上修饰的少量碳纳米管对腺嘌呤的氧化起增强作用.研究了腺嘌呤在修饰电极上的伏安行为,优化了电氧化的最佳条件,并对其进行含量测定.方法的线性范围为2.0×10-8~1.0×10-5mol/L,检出限为1.0×10-9mol/L.用于模拟样品中痕量腺嘌呤的测定,结果满意.  相似文献   

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