Micromeritics TRISTAR II PLUS Operator's Manual page 71

Adsorptive Properties (continued)
Selections
Dosing Method
[group box]
Ideal gas law with non-
ideality correction
[selection]
Maximum manifold
pressure [text box]
Mnemonic [text box]
Molecular cross-sec-
tional area [text box]
Non-condensing
adsorptive [check box]
Non-ideality factor
[text box]
Psat vs T [button]
TriStar II Plus Operator Manual
303-42800-01 (Rev M ) — Sep 2023
Description
ρ = liquid density
liq
ʋ = molar liquid volume
l
ʋ = molar gas volume at STP
g
Normal. Dose from a pressurized tank of gas attached to a gas inlet
port.
From Psat tube. Select if the Psat tube is to be filled with
condensed adsorptive and dosed from the Psat tube. Select this
option if using krypton. The analyzer will determine the maximum
pressure that can be dosed on the analysis temperature and the
saturation pressure information in Fluid Properties.
Use if there is no compressibility table for the gas being used or to
match existing data. This factor adjusts the ideal gas law for cal-
culating the quantity of gas in the cold free space. Most gases are
nearly ideal near room temperature and at pressures not much
above atmospheric pressure, so the cold free space is where the cor-
rection is most important. If selected, enter the non-ideality factor
field.
The highest pressure to which the manifold will be dosed. To avoid
damage to the analyzer, this number is limited to 925 mmHg. Low
pressure sources will require lower numbers. For gases to be used
for dosing after charging a tube from a gas inlet, enter the maximum
pressure for dosing from the inlet, not from the tube of condensate.
Enter the mnemonic name for the adsorptive. .
The area that a single adsorbed molecule occupies on the surface of
the sample. It is used in surface area calculations.
Select if using a non-condensing analysis gas. When selected, the
Density conversion factor field and the
abled.
Compensates for the forces of attraction between molecules in a real
gas. This value is used for a calculated free space.
Click to edit the Psat vs Temperature table. The table contains sat-
uration pressures and their corresponding temperatures. To edit,
click in a field and enter the value.
Adsorptive Properties
PSAT vs T button are dis-
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