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Metrohm 792 Basic IC User Manual

Page 105

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4 Operation

792 Basic IC

96

External standard calibration

External standard calibration (absolute calibration) is a key way of cali-

bration. Basically this procedure calculates the dependence of injected

component's quantity versus area (or height) of the corresponding

peak. This dependence is showed as a calibration plot with injected

quantity along the Y axis and peak area (or height) along the X axis. The

injected quantity Q

i

is calculated as product of component's concentra-

tion C

i

to the reduced injected sample volume V':

Q

i

= C

i

V'

The calibration function W

i

(R)

for each component is calculated using

the RSD method.

W

i

(R) = RSD(Q

ij

, R

ij

) = RSD((C

i

V'), R

ij

)

When quantification procedure is performed, a concentration C

i

(abso-

lute concentration of a component in the sample) is determined as a ra-

tio of the computed quantity W

i

(R

i

)

to the corrected volume of sample

injected V':

C

i

= W

i

(R

i

) / V'

Component table

792 BASIC IC / Method / Calibration / Components

If the component table is opened, the chromatogram window is split

into two parts. The upper one shows the chromatogram, the compo-

nent table appears in the bottom part of the screen. When moving into

the component table, a special cursor in the upper part of the window

jumps to the peak corresponding to the current component.

The

Components table

stores the following information on the compo-

nents to be analyzed: