LI-COR LI-870, Инструкция по использованию

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Appendix B. Equations summary
Zeroing CO
2
When the command for zeroing CO
2
is received, the instrument computes the
CO
2
zero term from equation B-21, where , , , and are averaged for
5 seconds.
B-21
Spanning H
2
O
When the command for setting the span for H
2
O is received, along with the target
concentration
W
T
, from the target concentration, the target absoprtance
α
T
is com-
puted from
B-22
LI-870 computes
S
w0
from equation B-23 , where is averaged over five seconds.
B-23
where
B-24
The instrument retains the following values, which are used for subsequent sec-
ondary spans:
B-25
Secondary Span H
2
O
When the secondary span command for H
2
O is received, the instrument computes
new values for both S
w0
and S
w1
. First, it measures a new and computes a new
from equation B-24. Then, it uses these plus the retained values ( and
from the previous normal span) to compute
B-6 Using the LI-870 CO₂/H₂O Analyzer