Thermo Scientific ISQ, Руководство пользователя

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4
Creating a Method
Creating a Method for the ISQ Mass Spectrometer
Thermo Scientific ISQ User Guide 41
8. In the Groups pane, review the information in each row. As you create scans in the Scans
pane, information in the groups pane is automatically displayed.
a. The Time column displays the time that the ISQ mass spectrometer begins to acquire
this particular group of scans after the GC starts.
b. The Total Scan Time column indicates the sum of all the scans in each segment. The
total scan time also contains the stabilization time that occurs between each scan. In
this method, beginning 2.5 minutes into the GC run, you will get a complete set of
scans every 0.816 seconds. At 4 minutes into the GC run, the scanning has
completely changed.Now the scans will repeat every 0.412 seconds until the GC run
is complete.
c. The Chrom Filter On column enables the chromatographic filter. This filter
smooths spectral data as it is acquired, which may increase the signal-to-noise ratio by
a factor of 2 or more. The chromatographic filter is most useful when at least four full
scans are acquired across a GC peak. This setting is typically left on.
d. Use the Chrom Filter Peak Width column to set the peak width to match the width
of the GC peak (in seconds). If the peak width is set too large, signal intensity may be
reduced. The default value is 1 s.
Note If some of the columns mentioned below are not shown in the Groups pane, you
can right-click on a heading and display them. You can also reorganize the columns by
clicking on the heading of a column and dragging it to the left or right.