3. RESULTS
The 18O characterization of our 6 different highly
enriched 18O waters were carried out by measuring QMS
spectra and fitting those spectra. As described in section 2.3.1, m/z
signals 17-21 from the QMS spectra were used for this spectral fitting
method. In Figure 4 an integrated true measured QMS signal from m/z
17-21 and the fitted signal from the bespoke program are compared, their
very small residuals (in the order of 10 ppm) are shown on top panel of
the figure. These residuals show that the fitted signals are in
excellent agreement with the measured signals. The displayed error bars
are the standard deviations of 14 measurements.
<Figure 4>