Micromeritics ASAP 2460, Operator'S Manual

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Analysis Conditions Files ASAP 2460 Operator’s Manual
3-16 246-42800-01 - Aug 2013
Adsorptive
(continued)
•
Adsorptive
dropdown list- defaults to the adsorptive listed on the
previous window.
•
Mnemonic
- enter the mnemonic name for the adsorptive.
•
Non-condensing adsorptiv
e - Select this option if this file is for a non-
condensing gas (adsorptive). When you select this option, the Density
conversion factor field and the
Psat vs. T
push button become disabled.
•
Maximum manifold pressure
- the highest pressure that the manifold
will be dosed to. To avoid damage to the instrument, this number is
limited to 925 mmHg. Low pressure sources, such as vapors, will
require lower numbers.
•
Non-ideality factor
- The factor compensating for the forces of
attraction between molecules in a real gas.
•
Density conversion factor
- This value is used to convert the gas
volume at STP to liquid volume for the adsorptive. It is the ratio of gas
density at STP to liquid density.
•
Therm. tran. hard-sphere diameter
- an estimate of molecular size
used in calculating the thermal transpiration correction.
•
Molecular cross-sectional area
- the area that a single adsorbed
molecule occupies on the surface of the sample. It is used in surface area
calculations.
•
Adsorbate molecular weight
- the molecular weight is used for the
weight % column of the isotherm tabular report and for the pressure
Dosing Method
group box - select the dosing method to be used.
–
Normal
- select for standard and high throughput analyses. Dose
from a pressurized tank of gas attached to a gas inlet port.
–
From last port
- select if the sample tube on the last port is filled
with adsorptive and dosed from the sample tube. This option is used
for krypton analysis.
Absolute pressure
dosing
checkbox
Select to specify pressure targets in mmHg, mbar, or kPa rather than relative
pressure. This option is typically selected when using adsorptives at
analysis conditions above the critical point of the gas; for example, H
2
adsorption on carbon at liquid nitrogen temperature.
Field or Button Description (continued)