The stable HCNOS isotope compositions can be reported as (a) the isotope ratio of two stable isotopes (R); (b) the isotope delta value (δ); and (c) the atom fraction of the isotopes (x). Recalculations between these different expressions are needed frequently and require the use of the absolute isotope ratio for the zero points of the stable isotope delta scales (R_std). The inconsistent use of R_std values may lead to a discrepancy in recalculated results.

中文翻译：

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重新计算HCNOS的稳定同位素表达：EasyIsoCalculator

稳定的HCNOS同位素组成可报告为（a）两种稳定同位素的同位素比（R）；（b）同位素δ值（δ）；（c）同位素的原子分数（x）。经常需要在这些不同表达式之间进行重新计算，并且需要使用绝对同位素比作为稳定同位素增量标度（R _std）的零点。R _std值的使用不一致可能会导致重新计算的结果存在差异。