LI-COR LI-870, Инструкция по использованию

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B-1 Using the LI-870 CO₂/H₂O Analyzer
Appendix B.
Equations summary
The LI-870 computes CO
2
concentrations using an equation of the form
B-1
where
c
is concentration,
f
() is the calibration function,
α
" is the absorptance,
g
(
α
,
P
) is the pressure correction,
S
(
α
) is the span, and
T
is the temperature (°C) of
the gas in the cell, typically 51.5 °C. Absorptance is computed from
B-2
α
' is a span corrected absorptance, and g(
α
',
P
) is the pressure correction.
B-3
S
(
α
) is the span function, and raw absorptance
α
is computed from
B-4
where
V
and
V
o
are the raw detector sample and reference readings, and
Z
is the
zeroing parameter.
Span is a linear function of absorptance.
B-5