| 摘要 |
A method of measuring an isotope ratio of a continuous sample in an isotope ratio spectrometer comprises: (a) measuring at least one sample isotope ratio over a measurement time period tns (n≥1) in the spectrometer; (b) measuring a sample concentration cns over at least a part of the measurement time period tns, (c) selecting a reference gas concentration cnref for the spectrometer for reference to the sample measured during the measurement time period tns on the basis of the measured sample concentration cns; (d) measuring an isotope ratio of the reference gas at the selected reference gas concentration cnref in the spectrometer; (e) calibrating the at least one isotope ratio of the sample measured during the measurement time period tns, having a sample concentration cns using the measured isotope ratio of the reference gas at the corresponding reference gas concentration cnref; and (f) determining a plurality of calibrated isotope ratios and a plurality of sample gas concentration measurements, each of the plurality of calibrated isotope ratios and the plurality of sample gas concentration measurements being for a different, respective time. |
