水样中237Np、239～241Pu和241Am快速同时分析OA

In nuclear emergency,it is crucial to quick assess the level and extent of radioactive contamination.Highly toxic transuranic nuclides(237Np,239-241Pu and 241Am)are the most important radionuclides in radioactive contamination.In the case for analysis of multiple radionuclides in the same sample,the reported analytical methods are often time-consuming/tedious by using multiple chromatographic separation resins for the separation of every single radionuclide.In this work,a rapid analytical method for simultaneously determining transuranium nuclides in water samples was developed by coupling triple quadrupole inductively coupled plasma mass spectrometry(ICP-MS/MS)with a single DGA resin column,Np,Pu,and Am were simultaneously enriched and purified.For monitoring chemical yields of Np/Pu and Am,the chemical recoveries are greater than 80％which is monitored using 242Pu and 243Am as tracers.O2 was used as reaction gas in the collision reaction cell(CRC)of ICP-MS/MS,the chemical reaction behavior of Np and Pu with O2 is similar,and Np/Pu reacts with O2 and converts to NpO2+/PuO2,and Am reacts with O2 and concerts to AmO+.237Np,239-241Pu and241 Am in the same solution were simultaneously measured by the He-O2 mode of ICP-MS/MS in the same run,and the cross contamination of 241Pu and 241Am(＜1％)was achieved using 8.0 mL/min He-0.37 mL/min O2 as reaction gas.A sensitivity of 814×106 s-1/(mg/L)for Np,799× 106 s-1/(mg/L)for Pu,and 1 027× 106 s-1/(mg/L)for Am is achieved,and the sensitivity ratio of NpO2+and PuO2+is close to 1,indicating that 242Pu is feasible as a non-isotope tracer of Np under this condition.The abundance sensitivity of U and the interference of polyatomic ions(1H238U+,1H2238U+,206Pb35Cl+,204Pb37Cl+,204Hg37Cl+,205Tl36Ar+and 209Bi16O2+)formed by U and matrix elements(Pb,Hg,Tl and Bi)are effectively inhibited.The detection limit(DL)of 1.84 fg/L for 237Np,2.08 fg/L for 239Pu,0.70 fg/L for 240Pu,0.66 fg/L for 241Pu and 1.27 fg/L for241 Am are approached,this is three orders of magnitude lower than the DL required in nuclear emergency situations(1 Bq/L).The developed method is validated by analyzing the spiked samples,and allows for the rapid,simultaneous detection of ultra-trace amounts of Np,Pu and Am in environmental water samples within 2.5 h.This significantly reduces analysis time and meets the requirement for emergency preparedness.