Quadrupole-based ICPMS

In spite of the high selectivity of the technique, quadrupole-based ICPMS is not totally free from spectral interferences. The occurrence of polyatomic ions that show the same nominal mass-to-charge ratio as the analytes of interest is a well-documented problem. In the last decade, the introduction of colUsion/reaction cells has helped to minimize the importance of spectral interferences [30]. These devices most often make use of selective ion-molecule chemistry in such cells, although it is also possible to profit from selective... 

Potential for coupling the same ETV device with more sophisticated ICPMS systems (e.g., a quadrupole-based ICPMS unit equipped with a collision/ reaction cell, an ICPMS instrument equipped with a ToF mass analyzer, or a single- or multicollector sector field instrument), to further improve the abovementioned possibilities. 

In an earlier work by the same group (Gunther-Leopold et al. 2003), sample dissolution was done by digestion in a high-pressure close vessel at 150°C for 3 h with HNO3/HF and the sample was then similarly diluted to 1 M HNO3 with 0.5 mg fuel g solution. In this work, the performance of the quadrupole-based ICPMS was compared with the MC-ICPMS and with TIMS measuranents, and unsurprisingly the quadrupole was less precise than the other two instruments, but as mentioned earlier this was remedied in their later work. 

Preliminary measurements were made with a quadrupole-based system and reported (Gunther-Leopold et al. 2003), but after a multicollector ICPMS was installed in the hot laboratory, more precise isotope ratio measurements were made. The results were adjusted by use of internal correction (known isotope ratio of the same element) or by a bracketing procedure with certified reference materials (external correction). Additional measurements were made with a specially designed laser-ablation system that was coupled to the ICPMS instrument. The nuclear fuel burn-up assessment was based on measurement of the ratio between Nd isotope and the four main fissionable nuclides ( U, Pu, and " Pu) for UOj or MOX fuel. " Nd is formed... 

The three main analytical methods used for characterization of the isotopic composition of single uranium-containing particles—LA-ICPMS, FT-TIMS, and SIMS—were compared (Pointurier et al. 2013). The variability of the measurements of several particles from the Nusimep-7 intercomparison exercise by each method and the error bars for each individual particle measurement were presented. The results obtained by LA-ICP-QMS were inferior to the other two methods, but it was noted that the signal intensity obtained in the LA-ICPMS measurements with a quadrupole-based mass spectrometer was lower by a factor of 10-20 than the SIMS and FT-TIMS, which accounted for the relative uncertainties. In an earlier work by the same group, the isotopic composition of UOjFj particles from the Nusimep-6 intercomparison exercise was analyzed by the three methods. The time needed for analysis of two samples, each with 30 uranium particles, was estimated for SIMS, SEM-LA-ICPMS, ET-TIMS, and FT-LA-ICPMS to be 4, 3.5, 21, and 13 days, respectively (Pointurier et al. 2011), in partial agreement with the estimates given above (Esaka et al. 2009). 

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