School of Engineering and Science - Jacobs University

for JMn-1 as described in Section 7.6 preclude definitive statements as to the reason
for this discrepancy, and further studies of this effect in JMn-1 are recommended.
Concentrations of Zr as reported for all CRMs in this study have been
determined solely using 90 Zr. Interferences on the 91 Zr isotope primarily result from
56 M 35 Cl interferences, where M can be Fe, CaO(H), or ArO, and the use of HNO 3 for
diluting samples will reduce these interferences. Good results using 91 Zr in an HCl
acid matrix appear to be limited to samples which contain more than ~40 mg/kg Zr,
and that contain less than ~10% Fe 2 O 3 . The use of 91 Zr for quantifying Zr should be
used with caution, and is likely to prove most useful only for samples diluted in
HNO 3 , or for those samples diluted in HCl for which the Mn content is high enough
to produce significant 55 Mn 35 interferences that preclude the use of 90 Zr for
quantifying Zr (see App. 2).
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