Vario Isotope Select元素分析仪在AMS石墨靶合成中的应用

Application of Vario Isotope Select element analyzer in synthesis of AMS graphite target

石墨单质是目前利用加速器质谱进行14C测量的最佳靶物质,在石墨靶的制备过程中,样品含碳量、回收率等是关键参数,决定了后续精确定量的合成石墨,进而获取精确的年代数据。该文采用德国Elementar公司生产的Vario Isotope Select元素分析仪,针对AMS石墨靶合成中不同类型的测年材料,进行了燃烧测试实验。确定了各类测年材料的含碳量、适宜样品量和通氧模式,获取了最优的分析方法。在此基础上,分析了不同材料的有机碳含量,计算了回收率,确定了最佳称量范围。该方法操作简便快速、灵敏度高,具有较高的精密度和准确度,适用于常见年代样品的氧化燃烧过程。

Graphite is the best target material for the measurement of 14C by the accelerator mass spectrometry.In the preparation of graphite target,carbon content and recovery rate are the key parameters,which determine the subsequent accurate and quantitative synthesis of graphite,and then obtain accurate age data.In this paper,the Vario Isotype Select element analyzer produced by German Elementar Company is used to test the combustion of different types of materials used in the synthesis of AMS graphite target.The carbon content,appropriate sample mass,oxygen mode and the optimum analysis method are determined.On this basis,the organic carbon content of different materials is analyzed,the recovery rate is calculated,and the best weighing range is determined.This method is simple,rapid and sensitive,and has high precision and accuracy,which is suitable for oxidation combustion process of common samples.