大面积低水平α放射性能谱源的制备和样品的测定方法

    THE PREPARATION OF LARGE AREA AND LOW LEVEL α-SPECTROMETRIC SOURCE AND THE DETERMINATION OF SAMPLES CONTAINING α-NUCLIDES

    • 摘要: 本文叙述了1400cm~2的α放射性能谱源制备工艺流程和样品中α核素的测定方法。通过样品处理,用超声波粉碎,在真空干燥箱中制成大面积源。湿颗粒度≤1μm,不均匀性<9.5%。牢固性满足要求,源分辨率为70keV(对70μg/cm~2,~(241)Am),制源流程半机械化。8小时可作一个样品。 样品在大面积α屏栅电离室中测量,绘成谱图,计算α核素的比活度,全程回收率为99.1±4.6%,方法下限为6.7×10~(-4)Bq/g(固体)。还测定了7种样品中α核素的谱图和比活度,并用IAEA标准参考物质进行比对。

       

      Abstract: The technological process of preparing 1400 cm2 α-spectrometric source and method of determination of α-nuclides in samples are described. This process includes the pretreatment of samples, the grounding of samples to near colloidal solution by supersonic breaker and the sticking of the sample micro-particles on aluminized polyester film in vacuum drying oven. The wet particle size is 1μm, the non-evenness--9.5%.The source is firm enough to meet therequirement. The resolution is 70 keV (for 70 μg/cm2, 241Am) . One sample can be prepared in 8 hours. This process is low in cost.The procedure of determination of samples containing α-nuclides is givenThe recovery of the whole procedure is 99.1%. The detection llmit of the method is 7×10-4 Bq/g (solid). The spectrogram and specific activity of seven kinds of samples have been determinated. The results of the standard soil material of IAEA analyzed are in agreement with the data.

       

    /

    返回文章
    返回