Metrohm 792 Basic IC User Manual
Page 104
4.4 Methods
792 Basic IC
95
Notations
R
Stands for response value, either
area or height, de-
pending on setting selected in the
Calibration graphs
window.
V
Sample
Volume
injected.
D
Dilution
coefficient, shows number of times to which
the initial solution is dissolved before injection.
V' = V / D
Adjusted volume
of injected sample. A correction is
made for the dilution coefficient.
C
Concentration of the component in the initial solution
(before dilution).
Q = C
•
V'
Quantity
of component, used for calibration curve
construction.
t
Retention time
. Time needed by the mobile phase to
flow through the separation system.
t
0
Void time
. Dead time needed by the mobile phase to
flow through the separation system.
t' = t – t
0
Corrected retention time
, called also net retention time.
L
Column
length.
v = L / t
0
Linear
Flow rate
.
W(R) = k
2
R
2
+ k
1
R + k
0
Calibration function (component quantity W vs. de-
tector response R). In the case of the most common
linear calibration curve Q = W(R) = k
1
R
it comes
through the origin. The concentration of the compo-
nent in the analyzed mixture is calculated by the for-
mula C = W(R) / V'.
RSD(Q, R)
Procedure, used for computation of regression coef-
ficients (k
0
, k
1
and k
2
) of the calibration function W(R)
using RSD (Residual Standard Deviation). The proce-
dure gets input as a set of calibration points (quantity
Q
vs. response R) and outputs the calibration func-
tion W(R) used for prediction of the component
quantity Q
i
= W(R
i
)
.
Subscript values used:
j
Stands for j-th calibration level run.
s
Stands for standard component.
i
Stands for component number.