Metrohm 761 Compact IC - Manual (Page 149)

4.4 Methods
761 Compact IC
139
raw concentration Absolute concentrations (raw quantity) of the
components, calculated as
C
i
= W
i
(R
i
) / V'
Total value for the column is the sum of con-
centrations for all components.
concentration% Normalization of concentrations for all peaks
using the NORM value entered in the Total % for
normalization field (default setting 100%):
C
i
% = NORM • W
i
(R
i
) / Σ W
i
(R
i
)
Total value for the column equals NORM for
the main table, and the sum of concentrations
in the group for the group table.
rel. concentration Relative concentration of the component rela-
tive to the standard component, assumes con-
centration of one of the components to be
known in advance. The concentration of the
component is calculated by the formula:
C'
i
= W
i
(R
i
) / V' = W
i
(R
i
) • C
s
/ W
s
(R
s
) ,
where V' = W
s
(R
s
) / C
s
is the effective (redu-
ced) volume of injected sample. The standard
component concentration C
s
is entered by the
user.
Total value for relative concentration column
does not include the concentration of the stan-
dard component.
rel. concentration% Relative concentration percent differs from con-
centration% by exclusion of standard compo-
nent(s) from summation, so that sum of all con-
centrations (excluding standard) equals
NORM
.
Total value for the column equals NORM value
for main peak table, and the sum of concentra-
tions in the group for Group table.
index
Linear or logarithmic retention index for identi-
fied components.
Total value for the column is a weighted index
average with absolute concentration as weight.
I = Σ (I
i
C
i
) / Σ C
i
.
type The types of components are designated by a
one-letter code:
R Reference component (used for peak identifica-
tion).
S Standard component.
C Calibration standard in the case it is different
from the quantification standard.