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Metrohm 844 UV/VIS Compact IC User Manual

Page 87

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3.3 Settings

844 UV/VIS Compact IC / Gebrauchsanweisung 8.844.1051

75

A selection can be made from three different spectra, the absorption
spectrum, intensity spectrum and the zero spectrum. Please note that
each time you click on

Absorption

,

Intensity

or

Zero

the function of the

button will be triggered.

The 844 measures the current intensity spect-

rum and sends it together with the last zero

spectrum to have been recorded to .

The absorption spectrum is recalculated from

these two spectra.

Absorption

The absorption (with the units mAU) is given on

the y-axis as a function of the wavelength (x-

axis). The absorption values are calculated for

all measured wavelengths and shown as spect-

rum. The calculation formula for the absorption

value is shown here as an example for the

wavelength set for measuring channel 1:

akt

Int

zero

Int

Abs

1

1

log

λ

λ

=

where:

zero

Int

1

λ

The intensity measured when

recording the zero spectrum at the
wavelength set for measuring
channel 1.

akt

Int

1

λ

The actual intensity measured at

the wavelength set for measuring
channel 1.

If you are working with a reference channel (can
be activated on the subtab

Configuration

) the

formula is as follows: