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 共查询到19条相似文献,搜索用时 135 毫秒
1.
MC98-A型多功能极谱仪研制   总被引:1,自引:0,他引:1  
以8090单片机作智能部件的小型多功能极谱仪,采用STD标准总线结构,汉字菜单式提示,人-机对话方式操作。以阳极溶出和电位溶出分析为主。用三种定量分析方法直接显示,打印出测试曲线和分析结果。  相似文献   

2.
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   

3.
电位溶出装置的组装及其性能测试   总被引:1,自引:0,他引:1  
利用实验室中原有的设备组装电位溶出装置,用于教学实验可直观地诠释电位溶出法的基本原理。操作简单,教学效果良好。  相似文献   

4.
连续流动电位溶出分析测定血清中镉,铅   总被引:1,自引:0,他引:1  
蔡震  漆德瑶 《分析化学》1992,20(7):862-862
1 引言 本文设计了微机控制的连续流动电位溶出分析系统,并应用此系统测定了血清中镉、铅元素的含量。测定时样品的电积和溶出在两种不同的介质溶液中完成,以消除样品中对溶出有影响的因素,改善溶出的信噪比。测定结果表明测试系统具有样品预处理简单及用量少,测试速度快,自动化程度高等特点,尤其适用于大批量样品的分析。  相似文献   

5.
红参的微量元素含量及溶出率研究   总被引:2,自引:0,他引:2  
采用电感耦合等离子体发射光谱法(ICP-AES)测定了红参中15种微量元素的含量及溶出率。结果显示在红参及其水煎液中Ca,Mg,Fe,Mn,Zn,Sr,Al元素的含量较高。Cr,Al,Mg,Cd,Ni,Fe元素的溶出率较高。  相似文献   

6.
本文对在玻璃碳电极上不可逆溶出催化的理论进行了研究,推导了溶出催化过程的电流方程,峰电流和峰电势方程,并用微计算机模拟出各种关系曲线,从理论方程得知溶出催化伏安法所得的峰电流比溶出伏安法的峰电流提高了二个数量级。本文还用钯的溶出催化实验验证理论方程,所得的实验结果均与理论方程相吻合。  相似文献   

7.
综述了近十年来矿产品中污染物的溶出方法和溶出特征的研究进展,着重介绍了湿度室测试、淋溶试验、静态浸泡试验和萃取试验等溶出方法,以及pH、淋溶或浸泡时间、温度、电导率、固液比以及矿产品自身粒径等试验条件对溶出量的影响(引用文献32篇)。  相似文献   

8.
利用ICP-MS光谱仪,探讨铜质水表中重金属的溶出,分析了水质、浸泡时间、pH值对重金属溶出的影响。各元素在模拟自来水中的溶出量是超纯水的1.5-2倍,溶出量由大到小依次为Cu,Pb,Cr(VI),Cd;一般在0.5d时出现溶出拐点,在4d时达基本饱和;在pH4的酸性水质中,各元素的溶出量为极大值。该方法适于铜质水表中重金属溶出的分析。  相似文献   

9.
邵勇  王曙 《分析科学学报》1999,15(4):328-331
设计制作了用于改换介质的简易电解池,并以旋转圆盘玻碳电极为工作电极,研究了其用于电位溶出分析改换溶出介质的可行性。以同时测定Pb^2+、Cd^2+为例,试验了改换溶出介质的条件。结果表明,改换介质可消除共存离子的干扰,只要选择合适的溶出介质,可有效地提高测定方法的分辨率和灵敏度。此方法用于矿样中铅和镉的同时测定,结果满意。  相似文献   

10.
煤中无机矿物组分的溶出性及其对水煤浆流变特性的影响   总被引:2,自引:4,他引:2  
用等离子体原子发射光谱考察了14种不同变质程度煤中的无机矿物质在煤浆分散体系中的溶出性,并就其对浆体流变特性的影响进行了讨论。结果发现;煤中无机矿物质的溶出性视煤种和煤中矿物质含量的不同而有很大差异,而且,除个别煤熔出相当数量的铝离子外,其余煤在浆体分散体系中溶出的无机矿物离子均主要以钙出子为主,其次为镁,铁离子。  相似文献   

11.
Muñoz E  Palmero S 《Talanta》2005,65(3):613-620
This paper provides a review that summarizes several examples of the literature from 1980 to 2003, to illustrate the applications of stripping potentiometry for the determination and speciation of arsenic in several samples. A discussion on the main advantages of stripping potentiometry in comparison with other electrochemical methods employed for arsenic determination is presented. Special attention is devoted to stripping modes (constant current or chemical stripping) and to issues related to the choice of working electrodes and supporting electrolyte. This approach has been also applied at arsenic determination in flow systems. A section is dedicated to speciation of arsenic and total arsenic determination and other to analytical characteristic of method and their interferences. An extensive compilation, organize by experimental and analytical parameters and real sample studied is presented.  相似文献   

12.
毛细管电泳多脉冲溶出安培检测方法的研究   总被引:1,自引:0,他引:1  
 摘要:将用于电化学检测的三电极与驱动电泳分离的电化学系统的接地电极在毛细管出口处的外面作适当的布置,可最大程度地减少高压电场对安培检测的干扰。多阶脉冲溶出安培检测方式提高了电流检测灵敏度,并可在一定程度上通过不同的溶出电位鉴别分离组分。将该方法应用于铜、锌、铅、铊、镉等离子的毛细管电泳分离,得到了较满意的结果。  相似文献   

13.
BasedonthefirstideaspresentedbyBeck',anewmethodcalledalternatingpulsecurrent-chronopotentiometricstrippinganalysis(APC-CPSA)hasbeendeveloped.Inthistechnique,duringthestrippingstepthecurrentimposedontheelectrol,ysi$cellcomprisesofanalternatingpulsecurrent(APC)andtheinherentdirectcurrentofCPSA.TheAPCisoperatedwithahighfrequencyinasquarewavemode.isandiRisdefinedastheanodicandcathodicpulsecurrent,respectively,isandtRisthetimeforwhichthesecurrentsflow.So,whenisandiRalternates,partsofthestri…  相似文献   

14.
《Electroanalysis》2006,18(23):2343-2353
SH‐ and SS‐groups content and their ratio is one of the most important factors of organism antioxidant system. Change in ratio of thiols to disulfides can serve as an indicator of oxidative stress. Anodic stripping voltammetry and anodic stripping voltammetric titration (direct and reverse variants) methods are proposed for determination of thiols and disulfides concentration. Disulfides are preliminary reduced with sodium sulfite. Ag++RSH→AgSR+H+ reaction is used to provide the information. Unreacted silver ions concentration is determined by anodic stripping voltammetry method using platinum working electrode. Calibration free method is suggested. The possibilities of express analysis of blood and its fractions are described. Reliability of results and accuracy are confirmed by model solutions analysis and recovery study of whole blood and its fractions. Results of whole blood, erythrocyte mass, plasma and serum taken from different groups of patients' investigations are given, that demonstrate perspectives of the application methods in clinical practice.  相似文献   

15.
Adsorptive stripping voltammetry (‘formazone-method’) is already known as one of the most sensitive methods for platinum analysis with a detection limit in the low picograms range. In this work, it is shown that the detection limit can be lowered even more by one order of magnitude to 0.2 pg (=1 fmol) Pt in 15 mL electrolyte, corresponding to 68 fmol/L, by applying forced convection during the stripping step of the voltammetric measurement. The sensitivity of the method (given in nA/pg Pt) is enhanced by a factor of 3-5 (in differential pulse mode and 15 mL vial), up to a factor of 30 (using square-wave mode and 3 mL vial). The maximum enhancement factor is limited by the maximum stirrer speed, which can be applied without negative effects on the hanging mercury drop electrode.To check for similar enhancement effects in other types of stripping methods, the behaviour of adsorptive stripping voltammetry for Pt is compared to conventional anodic stripping voltammetry (ASV) of lead, and to adsorptive stripping voltammetry of nickel and cobalt using their dimethylglyoxime (DMG) complexes. No enhancement effect is observed in ASV of lead upon stirring, and the nickel-DMG-system exhibits only a smaller enhancement factor of about 1.5. A reasonable explanation of the higher signal enhancement in the catalytic Pt-formazone-system is the mass transport of reaction products, namely hydrogen, away from the working electrode during the catalytic hydrogen evolution cycle.  相似文献   

16.
A new automated batch method for the determination of ultratrace metals (nanogram per liter level) was developed and validated. Instrumental and chemical parameters affecting the performance of the method were carefully assessed and optimized. A wide range of voltammetric methods under different chemical conditions were tested. Cadmium, lead and copper were determined by anodic stripping voltammetry (ASV), while nickel, cobalt, rhodium and uranium by adsorptive cathodic stripping voltammetry (AdCSV). The figures of merit of all of these methods were determined: very good precision and accuracy were achieved, e.g. relative percentage standard deviation in the 4-13% for ASV and 2-5% for AdCSV.The stripping methods were applied to the determination of cadmium, lead, copper, nickel, cobalt, rhodium and uranium in lake water samples and the results were found to be comparable with ICP-MS data.  相似文献   

17.
The paper describes a simple and low‐cost multisensing instrument based on neural network to monitor multiple environmentally significant metals in solution by implementing the potentiometric stripping analysis technique. Our analyzer consists of a measuring unit, implemented on a lap‐top/notebook computer equipped with a simple electronic circuitry, and a reusable sensor, based on glassy‐carbon technology. The current system has been characterized with synthetic samples containing different concentrations of lead, copper, cadmium and zinc, showing detection limits suitable for the first monitoring of metal traces. A linear relationship between peak area and concentration has been observed for all tested metals. Therefore, a simple linear regression can be used by the analyzer to determine the actual metal concentration from the PSA peak area. The presence of a second metal or of a real matrix, often, interferes with stripping measurements in different ways: compounds with oxidation potentials close to that of the analytes of interest may interfere if the instrument does not have sufficient resolution to resolve the overlapping PSA peaks; species which form intermetallic compounds with the analytes may result in erroneously low analyte concentration readings, since the oxidation potential of the intermetallic compound is rarely near that of the original analyte. In order to overcome these problems, the described analyzer has been integrated with a Neural Network algorithm, able to separate the different contributions, after a proper training.  相似文献   

18.
A study of chlorophenols using differential pulse cathodic stripping voltammetry (dpcsv) is reported. Of the wide range of chlorophenols investigated, only pentachlorophenol and 2,3,4,6-tetrachlorophenol yield stripping peaks.For pentachlorophenol in water, two peaks are obtained at stripping potentials of –1.2 V and –1.58 V versus SCE. In methanol, pentachlorophenol shows one peak with a stripping potential at –1.6 V versus SCE.In the case of 2,3,4,6-tetrachlorophenol in water, two peaks are observed at –1.06 V and –1.6 V versus SCE, while in methanol only one peak arises at a stripping potential of –1.6 V. A procedure was developed for the determination of pentachlorophenol in natural waters.  相似文献   

19.
微电极电位溶出法研究进展   总被引:2,自引:0,他引:2  
本文介绍用于电位溶出分析(PSA)的固体微电极的种类及制作,综述了该领域研究的理论进展、技术应用及其方法的优越性,引用文献41篇  相似文献   

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