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1.
锑电极电位溶出法测定锌、镉、铅   总被引:1,自引:1,他引:0  
提出了采用锑电极作为工作电极同时测定痕量重金属锌、镉、铅的电位溶出法。探讨了同时测定锌、镉、铅的最佳条件。在pH=5.0的HAc-NaAc缓冲溶液中,Zn2+、Cd2+、Pb2+分别在-1.07、-0.70、-0.52 V得到灵敏的电位溶出峰。沉积时间为60 s时,锌、镉、铅的质量浓度分别在0~16.0、0~1.6、0~0.08 μg/mL范围内,与各自微分电位溶出峰高呈线性关系,检出限分别为4.0、0.3、0.03 μg/L。测定了水样中痕量锌、镉、铅的含量,结果令人满意。  相似文献   

2.
巯基棉-阳极溶出法测定水中超痕量镉   总被引:3,自引:0,他引:3  
镉已被公认是危险的环境污染物之一,故常需测定环境中镉的含量。采用玻璃碳电极阳极溶出法测定镉,在国内外已有工作发表,但疏基棉-阳极溶出法测定超痕量镉未见报导。我们根据在pH6-7条件下,疏基试剂能掩蔽镉离子的报导,利用自制的巯基棉,使镉离子全部吸附于其上,然后将经0.01M盐酸洗脱的镉离子的浓缩液,电解富集后,进行阳极溶出测定。方法简便,可消除大量铜对测定镉的影响。适于分析天然水中镉的本底值(0.1—0.001微克/升)。  相似文献   

3.
固体汞合金电极电位溶出法同时测定痕量锌、镉、铅   总被引:5,自引:0,他引:5  
李建平  陆继勇 《应用化学》2006,23(9):1006-0
固体汞合金电极电位溶出法同时测定痕量锌、镉、铅;固体汞合金电极;电位溶出法;锌;镉;铅  相似文献   

4.
铋膜电极微分电位溶出法测定环境样品中生物可利用镉   总被引:7,自引:0,他引:7  
建立了环境样品中生物可利用镉的镀铋膜电极微分电位溶出分析法(DPSA),考察了同位镀铋膜测定镉的条件。结果表明在HAc—NaAc介质中镉可在镀铋膜电极上得到灵敏的微分电位溶出峰(V=-0.84V),最低检出质量浓度为0.6μg/L,结合3步连续萃取,利用标准加入法对环境样品中的生物可利用镉进行测定,相对标准偏差2.3%~4.1%,加标回收率97%~104%。  相似文献   

5.
研究了以羧基化的水溶性碳纳米管(CNT)作为增敏剂,经吸附富集,用方波溶出伏安法测定痕量镉.讨论了吸附溶出的机理,对富集时间、富集电位、镉浓度、HCI加入量的影响及部分离子干扰等进行实验,并对含镉水样进行测定.实验结果发现:Cd2 在-0.65 V左右出现灵敏的溶出峰,峰电流在Cd2 浓度为2.0~10 nmol/L时呈现良好的线性关系,检出限为0.1 nmol/L,回收率为94%~103%.  相似文献   

6.
研究了以常压低功率氩微波诱导等离子体(MIP)为原子化器的原子吸收光谱法(AAS)测定银和镉。采用电热蒸发(ETV),浓H2SO4吸收去溶的进样方法。考察了微波前向功率,载气流量,去溶电压,去溶时间,蒸发电压,酸度对银,镉测定的影响。方法已用于试样分析。  相似文献   

7.
铟中镉的极谱测定,由于在一般情况二者半波电位相差很小使直接测定发生困难,Pohl等在5N HBr 介质中用异丙醚多次萃取主体元素后再用经典极谱法测定镉等痕量杂质,该法灵敏度低.用脉冲极谱溶出法测定镉灵敏度很高,但大量铟存在下测定镉尚未见报导.我们用国产 JP-MI 型脉冲极谱仪,配合玻炭电极,在0.5M 乙二胺-0.5MKOH-5×10~(-5)MHg(NO_3)_2底液中,选择适当的电解电位,铟大于镉一千倍时仍能测定 ppb 级的镉.我们  相似文献   

8.
预镀铋膜阳极溶出伏安法测定废水中微量铅和镉   总被引:3,自引:0,他引:3  
本文采用预镀铋膜法修饰玻碳电极,并用该电极对废水中微量铅和镉同时进行了阳极溶出伏安法测定,研究了预镀铋膜测定铅和镉的条件。实验结果表明:铅和镉在铋膜电极上可得到灵敏的电位溶出峰,峰高和溶出电位与汞膜电极法相近,使用预镀铋膜电极可避免使用汞电极带来的环境污染。  相似文献   

9.
研究了一乙醇胺及其衍生物的非环状醇胺的分子结构与其吸收捕集CO2性能之间的关系.通过实验测定了在313.15K和393.15K两个温度下,CO2分压从1kPa到700kPa条件下,CO2在不同醇胺水溶液中的溶解度,分析研究了羟基与烷基间的链长、取代烷基位置、氨基上烷基链数目及烷基羟基链数目、羟基位置和两个羟基的影响.结果表明,不同分子结构的醇胺水溶液对CO2的吸收能力有明显差别.根据CO2的捕集分离要求,选择合适的溶剂,可大幅度提高溶剂的CO2捕集能力.  相似文献   

10.
高纯铝中ppm级镉、铅、铜杂质的测定,现普遍采用悬汞电极或铂球镀银沾汞电极阳极溶出法测定。本文利用玻碳电极导电性好,灵敏度高和氢的超电势高等优点,与阳极溶出法连用,解决了在一般试验室中可靠的测定高纯铝中ppb级镉、铅、铜杂质的问题。试验证明方法的灵敏度,镉为3.6×10~(-9)M,  相似文献   

11.
通过对氢氧化四甲胺溶解人体指甲样品分解方法的研究,建立了石墨炉原子吸收光谱法测定指甲中痕量镉的方法,方法具有试剂用量少,空白易控制,操作方便等优点,用此法对长期从事与镉接触的工作人群与普通人群指甲中镉含量的分析对比,初步揭示指甲作为样本具有代表性,长期从事接触镉的工作会引起镉在人体中的积累。  相似文献   

12.
The simultaneous dissolution of tetraoctylammonium bromide and sodium N-lauroyl sarcosinate in water leads to the in situ formation of a water-immiscible ionic liquid, tetraoctylammonium N-lauroyl sarcosinate. The new phase formed can extract cadmium, cobalt, copper, nickel, lead, and zinc ions from aqueous solution in the presence of 4-(2-pyridylazo)resorcinol (PAR), while it can extract cadmium ions in the absence of PAR.  相似文献   

13.
Electrorecovery of cadmium(II) on filtering carbon-graphite electrodes from washing cyanide solutions formed in cadmium-plating of articles in a cyanide electrolyte was studied. The effect of the dilution factor of the supporting electrolyte on the run of cathodic polarization curves, pH value, and solution resistivity was analyzed. The influence exerted by the efficiency of cadmium(II) recovery on the carbon-graphite electrodes was studied in relation to current density, solution flow rate, cadmium(II) concentration in solution, dilution factor of the supporting electrolyte, and material of the carbon-graphite electrode. The possibility of dissolution of cadmium deposited onto a filtering carbon-graphite electrode via anodic dissolution or because of the operation of a short-circuited electrochemical system constituted by the carbon-graphite electrode, cadmium, and cyanide solution was considered.  相似文献   

14.
本文提出从工业品原料提纯制备高精密标准电池的方法。有40个酸性电池(硫酸浓度0.0490N),在1973~1979年间,于规定时间测定电动势值,每年平均上升0.33μV.初步分析了影响电池电动势值稳定性的各种因素,提出了实验数据。  相似文献   

15.
国内离子交换法处理氰化镉废水的现状及改进意见   总被引:3,自引:0,他引:3  
本文对国内现行离子交换法处理氰化镀镉废水的工艺进行了探讨,提出了用络合理论将阴树脂由Cl-1型转变成CdCl42-型后交换,便可提高对水中游离氰(CN-)的吸附能力,并能使氰、镉都得到回收利用。  相似文献   

16.
A simple, environmentally friendly, cost-effective and sensitive method was developed for the determination of trace cadmium in rice and water by using flow injection (FI) on-line precipitation–dissolution in a knotted reactor (KR) as a preconcentration scheme for thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS). The preconcentration was achieved by online merging the sample solution and the precipitating reagent in a KR and subsequently eluting the resultant precipitate of cadmium hydroxide with 1 mol/L HNO3. The eluant was then introduced into TS-FF-AAS for the determination. A self-assembled FI system was employed to hyphenate the KR system with TS-FF-AAS. Under optimal chemical and instrumental conditions, a limit of detection of 0.04 μg/L and a sensitivity enrichment factor of 34 for cadmium was obtained with a total initial sample volume of 4 mL. The proposed method was applied to the determination of cadmium in certified reference rice and water samples with analytical results in good agreement with their certified values. Real rice samples and real water samples were also determined by the proposed method, with analytical results confirmed by inductively coupled plasma mass spectroscopy (ICP-MS).  相似文献   

17.
The possibility of recovering cadmium deposited on fibrous carbon electrodes from ammonium washing solutions formed in cadmium plating via operation of a short-circuited electrochemical system or anodic dissolution was examined. A polarization study of electrode processes that occur on a renewable graphite microelectrode in ammonium solutions of varied composition was carried out. The change in the properties of fibrous carbon electrodes in their cyclic use in electrodeposition-recovery of cadmium and the possibility of their repeated use were analyzed.  相似文献   

18.
Darkowski A  Cocivera M 《Talanta》1986,33(2):187-189
A polarographic method has been developed for the simultaneous determination of cadmium and tellurium in thin-film cadmium telluride. The procedure involves dissolution of the film with concentrated nitric acid, which is subsequently removed by evaporation. The Cd(II) and Te(IV) waves are well separated at pH 10, but sufficient ammonia must be present to prevent the precipitation of cadmium hydroxide.  相似文献   

19.
采用马来酸酐-醋酸乙烯共聚物乳液为模板,分别以水、乙醇和丙酮为脱模溶剂,合成了表面层(厚度为10μm)为大孔结构(孔径为250~400nm)的聚苯乙烯(PS)孔材料.用扫描电子显微镜(SEM)测定了材料表面的微观形貌,SEM照片显示出3种脱模溶剂均能制备PS大孔材料,其中水为脱模溶剂时对PS基材的不利影响最小.用傅立叶红外光谱仪(FTIR)表征了脱模后孔内被固定的特征基团,结果表明,不同的脱模溶剂分别对应不同的孔内基团,即水-羧基、乙醇-酯基及丙酮-酐基.测定了3种脱模溶剂的脱模速率,其顺序为丙酮>>乙醇>水.  相似文献   

20.
Yebra MC  Enríquez MF  Cespón RM 《Talanta》2000,52(4):631-636
A rapid, sensitive, accurate and precise flame atomic absorption method is described for the determination of cadmium in mussels. The method is based on the continuous precipitation of cadmium as an ion pair between tetraiodocadmate and quinine and dissolution of the precipitate with ethanol. The metal can be preconcentrated 32-fold using 15 ml of sample solution by using a time-based technique at a sampling flow rate of 3.0 ml min(-1). The proposed method allows the determination of cadmium in the range 0.25-5.5 mug g(-1). The precision (relative standard deviation) obtained for different amounts of cadmium is in the range 1.5-4.7% at the 0.25-5.0 mug g(-1) level. The method demonstrates high tolerance to interferences, and the data obtained are in agreement with the certified value of a selected reference material. This procedure was applied to the determination of cadmium in mussel samples from estuaries in Galicia (Spain).  相似文献   

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