Radioactive noble-gas isotopes, SSKr (half-life tl/2=10.8 y), 39Ar (tl/2=269 y), and SlKr (t1/2-229,000 y), are ideal tracers and can be detected by atom trap trace analysis (ATTA), a laser-based technique, fr...Radioactive noble-gas isotopes, SSKr (half-life tl/2=10.8 y), 39Ar (tl/2=269 y), and SlKr (t1/2-229,000 y), are ideal tracers and can be detected by atom trap trace analysis (ATTA), a laser-based technique, from environmental samples like air and groundwater. Prior to ATTA measurements, it is necessary to efficiently extract krypton and argon gases from samples. Using a combination of cryogenic distillation, titanium chemical reaction and gas chromatography, we demonstrate that we can recover both krypton and argon gases from 1-10 L "air-like" samples with yields in excess of 90% and 98%, respectively, which meet well the requirements for ATTA measurements. A group of testing samples are analyzed to verify the performance of the system, including two groundwater samples obtained from north China plain.展开更多
基金This work was supported by the Special Fund for Land and Resources Research in the Public Interest (No.201511046) and the National Natural Science Foundation of China (No.21225314 and No.41102151). We would like to give our gratitude to Zong-yu Chen from IHEG for organizing the field campaign.
文摘Radioactive noble-gas isotopes, SSKr (half-life tl/2=10.8 y), 39Ar (tl/2=269 y), and SlKr (t1/2-229,000 y), are ideal tracers and can be detected by atom trap trace analysis (ATTA), a laser-based technique, from environmental samples like air and groundwater. Prior to ATTA measurements, it is necessary to efficiently extract krypton and argon gases from samples. Using a combination of cryogenic distillation, titanium chemical reaction and gas chromatography, we demonstrate that we can recover both krypton and argon gases from 1-10 L "air-like" samples with yields in excess of 90% and 98%, respectively, which meet well the requirements for ATTA measurements. A group of testing samples are analyzed to verify the performance of the system, including two groundwater samples obtained from north China plain.