LI-COR LI-830, Руководство пользователя

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where V
c
and V
co
are the raw detector signals for sample and reference, Z
c
is the
CO
2
zero parameter, and X
wc
is a cross sensitivity parameter for the effect of water
vapor on CO
2
. Its value is reported on the calibration sheet as
XS=
.
The empirical pressure correction function g
c
() depends on CO
2
absorptance and
pressure:
When P = P
o
, g
c
() = 1.
When P < P
o
A-11
where a = 1.10158, b = -6.1217E-3, c = -0.266278, d = 3.69895, and z is the asymp-
totic value of absorptance, obtained from the calibration coefficients (equation
A-15).
A-12
When P > P
o
A-13
where X , A , and B are computed as in equation A-11. CO
2
concentration C (µmol
mol
-1
) is computed from
Appendix A. Equation Summary
A-3 Appendix A. Equation Summary