溶出伏安法测定乌药中的铜铅镉

在KNO3底液下,用线性扫描阳极溶出伏安法同时测定了乌药样品中铜、铅、镉3种金属的含量.结果表明,在最佳实验条件下,铜、铅、镉的峰电位分别为0.067、-0.45和-0.64V(vs ScE);铜、铅、镉金属离子的质量浓度在0-0.8 mg·L-1范围内,呈现良好的线性关系,相关系数分别为0.991 3、0.990 5...     

线性扫描阳极溶出伏安法测定酒中的铅

采用线性扫描阳极溶出伏安法测定酒中铅的含量，在0．1mol/L盐酸底液中，铅的加标回收率为97．4％～101．3％，测定结果的相对标准偏差为0．76％～3．32％，线性范围为0．02～1．10mg／L。     

阳极溶出伏安法测定血铅

本文采用一种金属交换剂(metexchange),使铅从红细胞中释放出来,再用阳极溶出伏安法进行测定。由于本法不用对血样进行消化处理,不仅加快了分析速度,而且避免了消化血样时可能带来的污染或损失。 1.仪器及测试条件: AD-1型极谱仪(江苏金坛分析仪器厂),XWT-206型台式记录仪(10mV),CSF-50型超声处理机,工作电极:银基汞膜电极,参比电极:Ag/AgCl电极,富集时间:1分钟,扫描电压:     

差示脉冲阳极溶出伏安法测定铅铊

采用自制流通池将介质交换技术和高灵敏度的差示脉冲阳极溶出伏安法相结合,在流动的含有样品的盐酸溶液中富集,而在静止的不含样品的乙二胺—氢氧化钠溶液中阳极溶出,得到了分辨率和灵敏度较高的溶出峰。从根本上解决了铅和铊阳极溶出峰相重叠的问题,从而实现了酸性溶液中铅和铊的同时测定。     

阳极溶出伏安法测定工业废水中痕量铅镉

玻碳汞膜电极阳极溶出伏安法测定铅镉已有人作了工作,本文将玻碳电极导线的汞接头改为镀铜焊接头,克服了使用过程中因电极内阻变化引起的异常现象及汞蒸气逃出对环境的污染,将通用的同位镀汞法改为先镀汞后富集,减少了例行分析中有毒汞盐的用量并提高了测定结果的精度。本法选取0.2MHAc-0.2MNaAc为基底溶液,氮气作除氧剂兼搅拌器,所得铅镉溶出伏安曲线的峰电位分别     

阳极溶出伏安法测定土壤中的铊

<正> 铊是一种有毒稀散元素,它在自然环境中含量甚微。通常用于测定的方法有荧光法,分光光度法、中子活化法、原子吸收光谱法、悬汞电极阳极溶出伏安法等。但这些方法如中子活化法不易推广,其它各方法用于环境污染监测灵敏度还不够。玻璃碳汞膜电极阳极溶出法可以达到较高灵敏度,这种方法已经用来测定海水、尿中的铊,但测定土壤中的铊尚未见有文献资料报道。我们试验了在不同介质中铊的阳     

阳极溶出伏安法测定水中溶解氧

测定水中溶解氧的方法很多。本文提出用阳极溶出伏安法(以下简称溶出法)测定水中溶解氧,其原理为:金属铊与水中溶解氧按下式定量地反应生成亚铊离子,4Tl+O_2+2H_2O→4Tl~++4OH~-然后用溶出法测定亚铊离子的浓度,间接求出水中溶解氧的含量。操作分为三步:(1)电解制备金属铊;(2)借金属铊的氧化固定水中溶解氧,(3)亚铊离子的溶出测定。使用883型极谱仪和银基汞膜球电极,测定亚铊离子的浓度范围为10~(-5)M～10~(-7)M,可测溶氧的浓度范围为10~(-3)M～2.5×10~(-8)M。测定氧的灵敏度可达2.5×10~(-8)M(相当于0.8ppb氧)。     

差示脉冲阳极溶出发伏安法测定铅铊

采用自制流通池将介质交换技术和高灵敏度的差示脉冲阳极溶出伏安法相结合，在流动的含有样品的盐酸溶液中富集，而在静止的不含样品的乙二胺－氢氧化钠溶液中阳极溶出，得到了分辨率和灵敏度较高的溶出峰。从根本上解决了铅和铊阳极溶出峰相重叠的问题，从而实现了酸性溶液中铅和铊的同时测定。     

Determination of Cu in Tequila by Anodic Stripping Voltammetry

Abstract

Concentrations of metals such as copper in alcoholic beverages must be strictly regulated due to negative effects ranging from beverage spoilage and hazing, to sensorial and health consequences. In this paper, a voltammetric alternative is presented for the analysis of copper in tequila, a Mexican spirituous alcoholic beverage. Anodic Stripping Voltammetry is applied and the standard addition method is used to quantify copper in this beverage at concentrations commonly present in tequila (<10 ppm) without sample pretreatment. Copper can be reduced and then oxidized quantitatively and reproducibly. A comparison of Anodic Stripping Voltammetry with Atomic Absorption Spectrometry is presented.     

Pt‐Nanoparticle Incorporated Carbon Paste Electrode for the Determination of Cu(II) Ion by Anodic Stripping Voltammetry

Pt‐nanoparticles were synthesized and introduced into a carbon paste electrode (CPE), and the resulting modified electrode was applied to the anodic stripping voltammetry of copper(II) ions. The synthesized Pt‐nanoparticles were characterized by cyclic voltammetry, scanning electron microscopy and X‐ray photoelectron spectroscopy techniques to confirm the purity and the size of the prepared Pt‐nanoparticles (ca. 20 nm). This incorporated material seems to act as catalysts with preconcentration sites for copper(II) species that enhances the sensitivity of Cu(II) ions to Cu(I) species at a deposition potential of ?0.6 V in an aqueous solution. The experimental conditions, such as, the electrode composition, pH of the solution, pre‐concentration time, were optimized for the determination of Cu(II) ion using as‐prepared electrode. The sensitivity changes on the different binder materials and the presence of surfactants in the test solution. The interference effect of the coexisted metals were also investigated. In the presence of surfactants, especially TritonX‐100, the Cu(II) detection limit was lowered to 3.9×10^?9 M. However, the Pt‐nanoparticle modified CPE begins to degrade when the period of deposition exceeds to 10 min. Linear response for copper(II) was found in the concentration range between 3.9×10^?8 M and 1.6×10^?6 M, with an estimated detection limit of 1.6×10^?8 M (1.0 ppb) and relative standard deviation was 4.2% (n=5).     

石墨炉原子吸收法测定香根草中痕量Pb、Cd、Cu

采用石墨炉原子吸收法直接测定了香根草中重金属的含量,通过一系列实验,确定了石墨炉法测定Pb、Cd、Cu的最佳灰化温度和原子化温度,考察了精密度和回收率。结果表明,该法操作简单快捷,样品用量少,灵敏度高,稳定性好。     

双硫腙修饰玻碳电极阳极溶出伏安法测定痕量镉和铅

报道了双硫腙修饰玻碳电极同时测定痕量镉和铅的电分析方法。镉和铅离子通过与电极表面的双硫腙发生螯合作用而富集在电极表面 ,同时在 -1 .2 0V(vs.SCE)还原成零价镉和铅 ,当电极电势从 -1 .2 0V向 -0 .3 0V扫描时 ,被还原的镉和铅从电极表面溶出 ,分别于 -0 .78V和 -0 .4 8V左右形成灵敏的阳极溶出峰。优化了支持电解质及pH值、双硫腙用量、富集电位及时间等实验参数。利用该修饰电极测定镉、铅的线性范围分别为 1 .0×1 0 - 8～ 2 .5× 1 0 - 6 mol L和 5 .0× 1 0 - 9～ 2 .5× 1 0 - 6 mol L。检测限分别为 5 .0× 1 0 - 9mol L和7.0× 1 0 - 1 0 mol L。该法用于实际水样中镉和铅的测定 ,平均回收率分别为 99.3 0 %和 99.5 4 %。     

Determination of Thiols and Disulfides in Whole Blood and Its Fractions by Anodic Stripping Voltammetry and Anodic Stripping Voltammetric Titration

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.     

电感耦合等离子体质谱法测定海洋贝类中镉、铬、铜和铅

采用微波消解法处理海洋贝类样品,用电感耦合等离子体质谱法测定样品中镉、铬、铜和铅等4种重金属元素的含量。选择111 Cd、53 Cr、63 Cu和208 Pb等待测元素的同位素克服了质谱干扰。4种元素分别在一定的质量浓度范围内呈线性,检出限(3s)在0.005～0.17μg.L-1之间。镉、铬、铜和铅的回收率分别为94.7%,102.1%,101.9%,105.3%;测定值的相对标准偏差(n=7)分别为4.3%,3.8%,1.5%,6.0%。     

丁二酮肟修饰碳糊电极阳极溶出伏安法测定痕量铋

报道了用丁二酮肟修饰碳糊电极测定微量铋的电分析方法。Bi~(3+)通过与电极表面的丁二酮肟作用而富集在电极表面,同时在-0.40 V(vs.SCE)还原成零价,当电极电势从-0.40 V向0.40 V扫描时,被还原的铋从电极表面溶出,在0.03 V出现一个十分灵敏的阳极溶出峰。优化了各种实验参数,如支持电解质的选择及pH值、丁二酮肟的用量、富集电位及时间等。修饰电极测定铋的线性范围为1×10~(-9)～1×10~(-6)mol/L。富集6 min后检出限可达4×10~(-10)mol/L。该方法简便快速,灵敏度高,分析成本低廉,并成功应用于实际水样中微量铋的测定。     

Sonoelectroanalysis: Anodic Stripping Voltammetric Determination of Cadmium in Whole Human Blood

The quantitative detection of cadmium in human blood is shown to be possible by anodic stripping voltammetry under conditions of insonation. An immersion horn probe is introduced into a thermostatted conventional three‐electrode cell opposite a Nafion‐coated mercury plated glassy carbon electrode. The enhanced mass transport associated with power ultrasound yields efficient preconcentration of the cadmium before it is detected using anodic differential‐pulse stripping voltammetry. Insonation further offers the crucial benefits of first surface activation and cleaning, helping to prevent electrode fouling by the organic components in blood and second fully equilibrating “free” and “bound” Cd²⁺ ions in the complex matrix. Acoustic streaming and cavitation promote the mass transport of cadmium to the surface of electrode, facilitating measurements in solutions of low cadmium concentration, where “silent” measurements fail to yield an analytical signal. The system is calibrated using standard micro additions of cadmium to give the total amount of cadmium in blood. The calibration plot, showing the dependence of the cadmium stripping peak height on cadmium concentration in 1 : 50 diluted blood samples, was linear in the range 1×10^?10 M to 4×10^?9 M Cd²⁺. The values of cadmium concentration obtained using sonoelectroanalytical methodology were compared with the results obtained by independent atomic absorption spectroscopy (AAS) measurements and good agreement was found.     

火焰原子吸收法连续测定茶叶中铅、铜、锌、镉含量

采用火焰原子吸收方法连续测定了茶叶中铜，铜，锌，镉的含量，方法灵敏，准确。测定时无需富集，萃取，操作简便，回收率93．0％－98．1％，相对标准偏差不超过5．3％。     

FAAS法连续分析测试电池锌粉中镁铁铜铅锰

提出了运用FAAS法连续分析测试电池锌粉中Mg、Fe、Cu、Pb、Mn的含量,给出了Mg、Fe、Cu、Pb、Mn最佳测定条件及线性范围,在测定中对样品中的干扰因素进行了综合考虑.方法具有很好的灵敏度和重现性,步骤简单、操作容易、干扰少.测定样品Mg、Fe、Cu、Pb、Mn含量的相对标准偏差均小于1.0%(n=10).标准加入回收率均在97.0%～101.5%(n=6)范围内.适用于电池锌粉中Mg、Fe、Cu、Pb、Mn的含量控制分析和样品系统分析.