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Metrohm 792 Basic IC User Manual

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4.4 Methods

792 Basic IC

91

Setup

Tab

Setup

of

Integration parameters

window with integration parameters.

The two most important of these parameters for peak recognition are

Width

and

Slope

.

If the signal-to-noise ratio of the chromatogram is high enough (e.g.

100:1 or higher), the integration algorithm is not too sensitive to

changes in integration parameters. On the contrary, if the baseline

noise is high, careful tuning of these parameters may be needed.

Number of peaks

Number of peaks detected (read-only).

Delay

Time delay before starting peak detection

(in min).

Entry range:

0}

}

}

}1440 min

Width

Peak width (at the baseline, in s).

This parameter is used for setting baseline start

and end points. If this value is too low, exces-

sive narrow peaks are detected from the base-

line noise. If it is too large, several adjacent

peaks or baseline drift can be integrated as a

single peak. For an optimal evaluation, it is rec-

ommended to enter the width of the narrowest

peak on the chromatogram (normally 2}10 s).

Entry range:

0.1}

}

}

}480 s

Slope

Threshold for peak recognition.

The value of the first derivation (slope) of the

curve is divided by the baseline noise (which is

estimated using a special algorithm) and the

result is compared with the

Slope

threshold

value. Reasonable range of

Slope

parameter is

0.5...25.

Entry range:

0.1}

}

}

}400