Röllin Stefan, Sahli Hans, Gnägi Lars, Corcho Alvarado José A
Nuclear Chemistry Division, Spiez Laboratory, Federal Office for Civil Protection, Austrasse, CH-3700 Spiez, Switzerland.
NBC Defence Laboratory 1, Swiss Armed Forces; Department of Chemistry and Biochemistry, University of Bern, Switzerland.
Chimia (Aarau). 2020 Dec 23;74(12):989-994. doi: 10.2533/chimia.2020.989.
A radiochemical procedure for the determination of plutonium (Pu) and uranium (U) radionuclides in ice samples by multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS) is presented. Pu and U radionuclides are preconcentrated by coprecipitation and then separated by extraction chromatography. The purified Pu and U fractions are analyzed by MC-ICP-MS. Detection limits of 2 × 10 -3 and 3 × 10 mBq kg were achieved for Pu and U, respectively. Surface ice samples collected from the Gauli glacier (Switzerland) were analyzed by this method. The surface of the Gauli Glacier retains historical records of Pu, Pu and U from the nuclear weapon testing (NWT) period. Pu and U radionuclides were found to be consistent in terms of pattern, showing two peaks possibly related to the two main periods of the NWTs (1954-1958 and 1961-1963). ³H measurements, also released by the NWT, further confirmed the Pu and U results. The Pu/Pu ratio ranged from 0.14 to 0.25, and U/ Pu ranged from 0.14 to 0.81. The Pu atom ratios ranged within the limits of global fallout in the most intensive period of NWT (1952 to 1962).
本文介绍了一种通过多接收电感耦合等离子体质谱仪（MC-ICP-MS）测定冰样中钚（Pu）和铀（U）放射性核素的放射化学方法。Pu和U放射性核素通过共沉淀进行预浓缩，然后通过萃取色谱法分离。纯化后的Pu和U馏分通过MC-ICP-MS进行分析。Pu和U的检测限分别达到2×10⁻³和3×10 mBq/kg。采用该方法对从瑞士高利冰川采集的表层冰样进行了分析。高利冰川表面保留了核武器试验（NWT）时期Pu、Pu和U的历史记录。发现Pu和U放射性核素在模式上是一致的，显示出两个峰值，可能与NWT的两个主要时期（1954 - 1958年和1961 - 1963年）有关。同样由NWT释放的³H测量结果进一步证实了Pu和U的结果。Pu/Pu比值范围为0.14至0.25，U/Pu比值范围为0.14至0.81。Pu原子比在NWT最密集时期（1952年至1962年）全球沉降的范围内。
