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Noise suppression: ADF™
AZURA® Detector ECD 2.1 Instructions, V6685
Fig. 27
Sine of Fig. 26: A full period is 0.41 min (25 s) which corresponds to
a frequency of 1/25 = 0.04 Hz.
7.3 Frequency of signal and noise
Also a chromatographic peak can be expressed in terms of frequencies.
The way to determine this frequency is the same. The duration of the full
peak is measured and expressed in Hz.
Fig. 28
Frequency tells how often something happens: 1 peak in about
0.25 min (15 s), f = 1/15 = 0.07 Hz.
This is further illustrated by an overlay of the same chromatographic peak
with a sine of 0.07 Hz (Fig. 29).
Fig. 29
Overlay of a chromatographic peak with 0.07 Hz sine.
-400000
-300000
-200000
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0
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4.0
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5.0
t (min)
4.56
4.15
40000
140000
240000
340000
440000
540000
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
5.0
4.05
3.8
40000
140000
240000
340000
440000
540000
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
5.0
Содержание Azura ECD 2.1
Страница 1: ...HPLC Detector ECD 2 1 Instructions Document No V6685 ...
Страница 31: ...27 ECD 2 1 controller AZURA Detector ECD 2 1 Instructions V6685 5 2 Overview of ECD 2 1 screens DC mode ...
Страница 32: ...28 ECD 2 1 controller AZURA Detector ECD 2 1 Instructions V6685 Pulse mode ...
Страница 33: ...29 ECD 2 1 controller AZURA Detector ECD 2 1 Instructions V6685 Scan mode CONFIC menu ...
Страница 34: ...30 ECD 2 1 controller AZURA Detector ECD 2 1 Instructions V6685 DIAG menu ...