Figure 3

Schematic explanation of how correction for scan time variability is performed. The example illustrates the effect of a ±20-min deviation from the targeted scan time (T=60 min). The straight lines define the K_m vs. SUR relation presuming ${\bar{V}}_{\mathrm{r}}=0.53$ and the linear Θ(T) relation according to Equation 7 with b=0.313. The correction procedure yields the SUR values which would have been measured if all scans had been performed at T=60 min. Without correction, there is a spurious fractional deviation that is roughly equal to the corresponding deviation of the actual from the targeted scan time (1/3 in this example).