铜箔恒温自沉积总α、总β计数法快速联测岩石、土壤及沉积物样品中的^(210)Pb、^(210)Bi、^(210)Po

The Conjoint and Rapid Determination of ^(210)Pb,^(210)Bi,^(210)Po in Rock and Soil Samples With GrossαandβCounter Spontaneously Deposited on Cu Foil Under Constant Temperature

研究了210Bi、210Po同时且定量恒温自沉积于铜箔的最佳制源条件,建立了双样-铜箔恒温自沉积总α、总β同时计数法快速联测岩石、土壤及沉积物样品中210Pb、210Bi、210Po的分析方法。试验发现,除酸度和温度等因素外,制源体系中的氯离子浓度也会对制源效果产生重要影响。当铜镀片面积为3.14cm2,盐酸浓度为0.5mol/L,氯化钠浓度为3.5mol/L,溶液体积为20mL,恒温90℃,振速为120次/min,振幅20mm,制源70min时,210Bi和210Po可同步定量自沉积且210Pb不沉积。Vc存在下,大量共存元素不干扰自沉积。方法的精密度优于5%,全程加标回收率在99.5%～100.5%之间。

The optimum spontaneous deposition conditions of 210 Bi and 210 Po on Cu was studied in this pa- per, and a double samples conjoint and rapid testing method of 210Pb,210Bi,210Po in sedimen rock and soil samples have been set up by counting gross a and ]3 simultaneous deposited on Cu foil under constant tem- perature . The research results shew that the concentration of chloride ion has an important impact on 210 Po or 210 Bi spontaneous deposition coefficient of recovery besides the concentration of HC1 and the tem- perature of solution. Under the conditions of the Cu foil area being 3.14 cm2 , the concentration of HC1 being 0.5 mol/L, the concentration of NaC1 being 3.5 mol/L, the volume of solution being 20 mL, the constant experiment temperature being 90C, the vibration frequency being 120/min, the vibration ampli- tude being 20mm and the spontaneous deposition time being 70rain, the spontaneous deposition of 210Bi and 210Po on Cu foil are simultaneous and quantitative and 210pb is not deposited. In case of Vc presence, lots of coexisting elements do not produce interference to testing. Degree of precision of this testing tech- nology is higher than 50//00 and total recovery rate reaches 99.5%-100.5%.