Inficon HAPSITE ER, Руководство по эксплуатации

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074-471-P1E HAPSITE ER Operating Manual 345 / 436
Window Expand Factor This option multiplies the retention time of the peak by the Window
Expand Factor to give a period of time by which the search window will be
expanded. For example, if the peak retention time is 10 minutes and the
Window Expand Factor is set to its default setting of 0.05, the 10 minute
retention time will be multiplied by the 0.05 Window Expand Factor to
equal 30 seconds. Then, 30 seconds is added to the Search Window . If
the default value of the Search Window is 20 seconds, adding 30 seconds
from the Window Expand Factor to the Search Window would increase
the search range to 50 seconds.
Min. Width This value is the minimum number of scans per peak, which designates the
area measurement for peak integration. Any peaks with fewer scans than
this value will be disregarded by the software. Decreasing this number will
result in the software accepting broader peaks.
Min. Fit This compares the mass intensities of the compound to those saved in the
library. Reasonable values depend on the selectivity of the calibration, but
typically 0.5 to 0.9 is used. A higher Min. Fit number is more discriminative.
Peak Resolution (dx) This number indicates the minimum number of scans between two peaks.
It is used to determine whether a peak should be considered a single peak
or if the peak should be split into two separate peaks.
Max Width This value is the maximum number of scans per peak, which designates
the area measurement for peak integration. Any peaks with more scans
than this value will be disregarded by the software. Increasing this number
will result in the software accepting broader peaks.
Min. Purity This compares the purity level of the detected peak to the mass peak in the
library. Reasonable values depend on the selectivity of the calibration, but
typically 0.5 to 0.9 is used. A higher Min. Purity number is more
discriminative.
Noise Level Mult The peak intensity must be greater than the product of the Noise Level
Mult number multiplied by the baseline noise in order to be identified as an
analyte.
Precedence Level Determines if the search uses the global parameters or compound-specific
parameters. Leaving this set to zero allows the use of specific search
parameters for individual compounds as discussed in Calibration [
}
370].
Min. Area This number discriminates against low responses which are usually
attributed to noise rather than analyte detection. Increase this number to
10,000 or more if false positives are encountered.
Max Width The peak must contain less scans than the setpoint number.
Low Mass NIST will only use masses above this setpoint to make an identification.
High Mass NIST will only use masses below this setpoint to make an identification.
Minimum Match Factor The net fit in AMDIS must be above this number.