Buchi DuMaster D-480, Operation Manual

Page: 150 / 354

Operating instructions DuMaster D-480 ©BÜCHI Labortechnik AG
7 - Using the instrument 150
Mean value
The mean value of "n" element concentrations is computed with this formula:
whereas:
/c = Mean value of concentrations
c
i
= Individual concentrations in the group
n = Number of group members
i = index from 1 to n
Absolute standard deviation
Absolute standard deviation is computed according to this formula:
whereas:
s = Absolute standard deviation
c
i
= Individual concentrations in the group
n = Number of group members
i = index from 1 to n
Relative standard deviation
Relative standard deviation is computed according to this formula:
whereas:
s
rel
= Relative standard deviation
s = Absolute standard deviation
/c = Mean value of concentrations
Delta
Delta is computed according to this formula:
whereas:
δ = Delta
c
max
= Highest element concentration in a group
c
min
= Lowest element concentration in a group
Manual peak integration
What is "manual peak integration"?
The instrument software offers the possibility to manually determine area values of peaks measured
during an analysis run.
Why manual peak integration?
Normally the measurement of the peak areas (integration) is done automatically in the control
electronic and/or the firmware of the analyzer itself. In few cases, it may be possible that the
automatic integration algorithm does not give satisfactory results, in particular if two peaks are
superimposed etc. In these cases the "manual reintegration" is recommended.
Peak types
In these instructions you will find different peak types. Their characteristics are listed in the follwing.