Micromeritics AccuPyc 1330, Руководство оператора

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Since P
1
, P
2
, and P
a
are expressed in equations (1) through (9) as absolute
pressures and equation (9) is arranged so that P
a
is subtracted from both P
1
and P
2
before use, new P
1g
and P
2g
may be redefined as gauge pressures
P
1g
=
P
1
−
P
a
(10)
P
2g
=
P
2
−
P
a
(11)
and equation (9) rewritten as
V
SAMP
=
V
CELL
−
V
EXP
P
1g
P
2g
−
1
(12)
Equation (12) then becomes the working equation for the pycnometer. Calibra-
tion procedures are provided to determine V
CELL
and V
EXP
and the pressures
are measured by a gauge pressure transducer. Provisions are made for conven-
iently charging and discharging gases at controlled rates, for optimizing the
relative sizes of the sample chambers and expansion volumes, and for cleans-
ing the samples of vapors which would render equations (1), (2), and (3) in-
adequate to describe behavior.
AccuPyc 1330 APPENDIX B
September 1996 B-3