Figure 6.

Comparison of sampling schedules on a simulated spectrum of 2 indirect dimensions including Gaussian noise. Nine peaks of relative intensities 2 to 10 were created. A: Complete spectrum simulated. The central area containing the peaks is boxed and expanded in the panels of the rest of the figure. B: Contour plots of the central part plotted at two different starting levels of lowest contours. The contours are spaced by a factor of 1.5, and the relative intensity is indicated in the right-hand panel. C and D: Peak recovery with the best (C) and worst (D) of the 100 Gaussian noise sets. As best and worst noise sets we selected those that resulted in the lowest and highest L² values for the selected area containing the peaks. This indicates the quality range of peak recovery one can expect. The six panels in C and D correspond to the same total number of scans. Thus, 16 times more scans per increment can be collected for the NUS data. To take account of this we multiplied the added noise by a factor of four for the US spectra (top left panel). The simulations show that NUS recovers the peaks in the noisy spectrum significantly better than US when equal measuring times are considered. For all NUS schedules the best of 100 seed numbers were used as selected with minimizing the point spread function. (C)