The behaviour of the complexes of copper,lead,cadmium and antimony with salicylfluorone (SAF) adsorbed on HMDE has been investigated by derivative chronopotentiometry in NH_3/NH_4C1. The dependence of the peak height...The behaviour of the complexes of copper,lead,cadmium and antimony with salicylfluorone (SAF) adsorbed on HMDE has been investigated by derivative chronopotentiometry in NH_3/NH_4C1. The dependence of the peak height on the dt/dE vs E curve on preconcentration time, the pH of solution and the constant reducing current are discussed. This method achieved the simultaneous determination of copper, lead, cadmium and antimony in human hair.展开更多
A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopoten...A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopotentiometry can be: enhanced about one order.展开更多
The theory of if-E curve in cyclic derivative chronopotentiometry is presented. Theoretical equations of if-E curves in the case of quasi-reversible and irreversible electrode reactions are deduced respectively.
Theories of the second reciprocal derivative chronopotentiometry analysis were deduced and experimentally verificated.Results in this study show that chronopotentiometry is significantly developed in both sensitivity ...Theories of the second reciprocal derivative chronopotentiometry analysis were deduced and experimentally verificated.Results in this study show that chronopotentiometry is significantly developed in both sensitivity and resolution for signals treated by the second reciprocal derivative.展开更多
A new method of oscillographic chronopotentiometry at silver disk electrode was investigated. By using it, a series of ions such as Pb, In, Cr, Tl, Bi etc. were determined. The detection limits are two or three orders...A new method of oscillographic chronopotentiometry at silver disk electrode was investigated. By using it, a series of ions such as Pb, In, Cr, Tl, Bi etc. were determined. The detection limits are two or three orders of magnitude lower than those by oscillographic chronopotentiometry at mercury electrode. The proposed method is characterized by fine sensitivity, stable oscillogram and no mercury. The research on the mechanism of this method shows that these achievements are caused by the characterristics of silver electroxidation and electroreduction and the oscillographic chronopotentiometry (OC).展开更多
Introduction Quantitative analysis in cyclic derivative chronopotentiometry(CDC) is based on the measurement of the depth of incision on the (dE/dt)～E curve. A serious disadvantage of the method is that a large charg...Introduction Quantitative analysis in cyclic derivative chronopotentiometry(CDC) is based on the measurement of the depth of incision on the (dE/dt)～E curve. A serious disadvantage of the method is that a large charging current obscures the measurement. To improve the sensitivity and the accuracy of CDC, a microcomputer-based data acquisi-展开更多
The equations of the second and third order derivative curves of time with respect to potential for a reversible process in adsorption chronopotentiometry are derived and experimentally verified.
This paper presents a new method called improved oscillographic chronopotcntiometry. It changes the incision of dE/dt-E curve into a peak shape and has the advantages of good reproducibility and wider linear range.
Cyclic voltammetry and chronopotentiometry were used to study the reaction mechanism of Pb（Ⅱ） and the co-deposition of Pb,Mg and Li on molybdenum electrodes in LiCl-KCl-PbCl2-MgCl2 melts.The diffusion coefficient o...Cyclic voltammetry and chronopotentiometry were used to study the reaction mechanism of Pb（Ⅱ） and the co-deposition of Pb,Mg and Li on molybdenum electrodes in LiCl-KCl-PbCl2-MgCl2 melts.The diffusion coefficient of lead ions in the melts was determined by different electrochemical techniques.The results obtained by cyclic voltammetry and chronopotentiometry indicated that the underpotential deposition of lithium on pre-deposited Pb leads to the formation of a liquid Li-Pb alloy,and the Mg-Li-Pb alloys are formed after the addition of MgCl2.X-ray diffraction confirmed that in the Mg-Li-Pb alloy,PbLi3,Mg2Pb and Li7Pb2 phases exist by galvanostatic electrolysis at 6.21 A/cm2 for 2 h at 873 K and the phases can be controlled by changing the concentration of PbCl2 and MgCl2.展开更多
By applying the convolution technique to the treatment of oscillographic signal,a new electroanalytical method,0.5-3.5 order differential A.C.oscillographic chronopotentiometry is presented.This note represents the ex...By applying the convolution technique to the treatment of oscillographic signal,a new electroanalytical method,0.5-3.5 order differential A.C.oscillographic chronopotentiometry is presented.This note represents the experimental circuits,principle and characteristics of the method.展开更多
Applying Fourier transform technique to deduction of background and noise on dE/dt-t curve,a new electrochemical method,high order harmonic oscillographic chronopotentiometry is proposed in this paper.
基金Project is supported by Natural Science Foundation of Shandong Province
文摘The behaviour of the complexes of copper,lead,cadmium and antimony with salicylfluorone (SAF) adsorbed on HMDE has been investigated by derivative chronopotentiometry in NH_3/NH_4C1. The dependence of the peak height on the dt/dE vs E curve on preconcentration time, the pH of solution and the constant reducing current are discussed. This method achieved the simultaneous determination of copper, lead, cadmium and antimony in human hair.
基金The authors gratefully acknowedge the financial support from the National Natural Scicllcc Foundation of China Nat
文摘A novel electroanalytical method. oscillographic chronopotentiometry with high and low frequency current. is presented in this paper. With this method, the sensitivity or almost all kinds of oscillographic chronopotentiometry can be: enhanced about one order.
基金Supported by the National Natural Science Foundation of China
文摘The theory of if-E curve in cyclic derivative chronopotentiometry is presented. Theoretical equations of if-E curves in the case of quasi-reversible and irreversible electrode reactions are deduced respectively.
基金Project supported by the Natural Science Foundation of the Education Committee of Hunan Province.
文摘Theories of the second reciprocal derivative chronopotentiometry analysis were deduced and experimentally verificated.Results in this study show that chronopotentiometry is significantly developed in both sensitivity and resolution for signals treated by the second reciprocal derivative.
文摘A new method of oscillographic chronopotentiometry at silver disk electrode was investigated. By using it, a series of ions such as Pb, In, Cr, Tl, Bi etc. were determined. The detection limits are two or three orders of magnitude lower than those by oscillographic chronopotentiometry at mercury electrode. The proposed method is characterized by fine sensitivity, stable oscillogram and no mercury. The research on the mechanism of this method shows that these achievements are caused by the characterristics of silver electroxidation and electroreduction and the oscillographic chronopotentiometry (OC).
基金Supported by the National Natural Science Foundation of China
文摘Introduction Quantitative analysis in cyclic derivative chronopotentiometry(CDC) is based on the measurement of the depth of incision on the (dE/dt)～E curve. A serious disadvantage of the method is that a large charging current obscures the measurement. To improve the sensitivity and the accuracy of CDC, a microcomputer-based data acquisi-
文摘The equations of the second and third order derivative curves of time with respect to potential for a reversible process in adsorption chronopotentiometry are derived and experimentally verified.
文摘This paper presents a new method called improved oscillographic chronopotcntiometry. It changes the incision of dE/dt-E curve into a peak shape and has the advantages of good reproducibility and wider linear range.
基金Projects(50871033,21173060,21103033) supported by the National Natural Science Foundation of ChinaProject supported by the Fundamental Research Funds for the Central Universities,ChinaProjects(2011AA03A409,2009AA050702,2007CB200906) supported by the Basic Research Foundation of Harbin Engineering University,China
文摘Cyclic voltammetry and chronopotentiometry were used to study the reaction mechanism of Pb（Ⅱ） and the co-deposition of Pb,Mg and Li on molybdenum electrodes in LiCl-KCl-PbCl2-MgCl2 melts.The diffusion coefficient of lead ions in the melts was determined by different electrochemical techniques.The results obtained by cyclic voltammetry and chronopotentiometry indicated that the underpotential deposition of lithium on pre-deposited Pb leads to the formation of a liquid Li-Pb alloy,and the Mg-Li-Pb alloys are formed after the addition of MgCl2.X-ray diffraction confirmed that in the Mg-Li-Pb alloy,PbLi3,Mg2Pb and Li7Pb2 phases exist by galvanostatic electrolysis at 6.21 A/cm2 for 2 h at 873 K and the phases can be controlled by changing the concentration of PbCl2 and MgCl2.
基金supported by the National Natural Science Foundation of Chinaby the Special Subject Foundation of Educational Committee of Shaanxi Province.
文摘By applying the convolution technique to the treatment of oscillographic signal,a new electroanalytical method,0.5-3.5 order differential A.C.oscillographic chronopotentiometry is presented.This note represents the experimental circuits,principle and characteristics of the method.
基金supported by the National Natural Science Foundation of Chinaby Special Subject Foundation of Educational Committee of Shanxi Province.
文摘Applying Fourier transform technique to deduction of background and noise on dE/dt-t curve,a new electrochemical method,high order harmonic oscillographic chronopotentiometry is proposed in this paper.
