Micromeritics TRISTAR II PLUS Operator's Manual page 77

Analysis Conditions (continued)
Selections
Options [button]
TriStar II Plus Operator Manual
303-42800-01 (Rev M ) — Sep 2023
Description
Available when the Target Pressures option is selected.
First Pressure Fixed Dose.
This option is most frequently used when performing a standard
nitrogen analysis of mesoporous materials such as catalysts. If
the first pressure table point is low and the gas uptake of the
sample is expected to be high, this option can shorten the time
required to reach the first point on the pressure table.
The sample is dosed repeatedly at low pressures with a specified
amount of gas until the first pressure point is reached. This initial
dosing quickly meets the adsorptive demand of the sample.
The first point on the pressure table is the threshold value,
triggering the transition from the Fixed Dose Mode to Pressure
Table Mode. When the first pressure table value is reached, Fixed
Dose Mode is disabled, and points are equilibrated and recorded
in accordance with the specified pressure table.
Enter the amount of gas to be added to the sample for each dose
cycle.
Maximum volume increment.
Select to determine when additional data points are collected
between target pressures in regions of adsorption. When the
maximum increment has been adsorbed since the last collected
data point, another point is equilibrated and collected. During
desorption, this field is treated as a maximum volume decrement
value.
Absolute / Relative pressure tolerance.
Analysis Conditions
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