Figure 7–4: Overlay of a chromatographic peak with 0.07 Hz sine
Narrow chromatographic peaks are typically in front of a chromatogram, while peaks with longer
retention times get wider. As a consequence, frequencies are not constant but vary between 0.1
and 0.01 Hz, which corresponds to 10 – 100 s peak width
Figure 7–5: Typical chromatogram with peak widths between 10 and 100 s
Noise in chromatography can come from various sources. Pump pulsations are typically shown
as a very regular noise pattern, while electronic noise has a more random character. This is
illustrated in
Figure 7–6: Typical random noise in chromatography (lower trace) (Page 67)
,
where a noise trace is shown with an overlay of 10 and 0.4 Hz sines.
December 16, 2021, 715007395 Ver. 00
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