Micromeritics ASAP 2460 Operator's Manual page 341

ASAP 2460 Operator's Manual
a.) The thickness of the adsorbed layer at the end of the interval is calculated using the equation
located in
Thickness Curve
For the last pressure interval from the lowest Pr
lations from the equations in
For the first pressure interval, there are no previously opened pores so the volume of liquid
desorbed from walls of previously opened pores is zero (Vd
(a) is skipped.
The change in thickness of the wall layer due to desorption from previously opened pores is
calculated as:
Tw
The annular cross-sectional area of the wall layer desorbed is calculated for all previously
opened pores:
CSA
The total volume of gas desorbed from walls of previously opened pores is calculated:
Vd
i
where LP
j
246-42800-01 - Aug 2013
Calculations, page C-44.
Thickness Curve
= Tw – Tw
1 i + 1
2
 Rc    
= + Tw –
j j

   
= LP CSAa
j j
j
= length of previously opened pores as calculated in Step b(2).
to zero relative pressure, reference the calcu-
i
Calculations, page C-44.
= 0), and the remainder of Step
1
2
 
cm
2 – 16
 10
--------- -
 
Rc
j
2
 
Å
for all previously opened pores
Appendix C
C-17