Waters 2998, Обзор и руководство по обслуживанию

Страница: 24 / 94

December 5, 2017, 715004753 Rev. B
Page 24
Figure 1–8: Resolution comparison for anthracene
1.5.3.2 Average chromatographic sampling rate
Sample rate is the number of data points acquired per second. The number of times a given pixel
is read during the sample rate interval depends on its exposure time. For example, if exposure
time is 25 ms and sample rate is 20 Hz, then exposures per sample is
The readings are averaged and reported as a single data point. The baseline noise decreases as
the number of exposures/sample increases.
Tip:
The amount of data stored is based on wavelength range, spectral resolution, runtime, and
sample rate. Specify these parameter values on the General tab of the PDA Instrument Method
Editor. For details, refer to the Empower or MassLynx online Help.
3.20 3.30 3.40 3.50 3.60 3.70 3.80 3.90 4.00 4.10
4.20
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
Ab
so
rb
an
ce
252 nm at 1.2 nm, height 0.53
252 nm at 6.0 nm, height 0.45
252 nm at 12.0 nm, height 0.35
20 samples/second = = 2 exposures/sample
(1000 ms/second)
(20 samples/second)(25 ms/exposure)