Alpha-S Method - Micromeritics Gemini VII 2390a Operator's Manual

Gemini VII

Alpha-S Method

The Alpha-S plot converts the standard adsorption isotherm into a dimensionless isotherm using the
quantity adsorbed at a relative pressure of 0.4. In the Selected Reports list box, highlight Alpha-S
Method, then click Edit.
One predefined curve is shipped with the analysis program and is located in the Reference directory.
Use the table to enter relative pressure and the alpha-s values.
Field or Button
Open button

Relative pressure
range text boxes
Fitted Alpha-S range
text boxes

Ref. surface area
text box
239-42828-01 - Dec 2012
To import values from an existing thickness curve (.ALS ASCII file), click
Open, and select the file containing the values.
The table to be imported must be saved as ASCII text with a .ALS
extension. It must have a two-column format with the relative pressures in
the first column and the alpha-s values in the second column. Columns
must be separated by a space or a tab.
Enter the pressure range when calculation assignments are not used.
Enter minimum and maximum relative pressures to determine the fit.
Enter the surface area from the reference curve. This value is used to
calculate the sample surface area.
Description
Report Options Files
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