Reference material IAEA-N-2 is aimed at δ15N calibrations.
The IAEA-N-2 is a relatively coarse grained dried salt of ammonium sulfate [(NH4)2 SO4] prepared by E. Salati, CENA (Centro de Energia Nuclear na Agricultura), Brazil, in the period of 1978 to 1983 [1, 2]. Its δ15N value is determined using data from several interlaboratory comparisons and assessments [2-5].
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