Micromass Quattro Ultima, Руководство пользователя

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In the case of too many consecutive peaks missed:
Check the data in the on-screen calibration report to see if the missed peaks are
present in the acquired calibration file.
If the peaks are not present then the first three reasons above are likely causes.
If the peaks are present in the data but are not recognised during calibration
then the latter four are likely reasons.
Having taken the necessary action, proceed as follows:
If
Intensity threshold
,
Initial error
and
Peak window
are adjusted to
obtain a successful calibration, check the on-screen calibration report to ensure
that the correct peaks have been matched.
With a very low threshold and wide ranges set for the initial error and peak
window it may be possible to select the wrong peaks and get a “successful”
calibration. This is particularly relevant for calibrations with PEG where there
may be peaks due to PEG+H
+
, PEG+NH
4
+
, PEG+Na
+
, and also doubly charged
species.
Select OK from the calibration report window to accept the new calibration, or
select Cancel to retain the previous calibration.
Mass Calibration
Page 119
Quattro Ultima
User's Guide