Appendix F ASAP 2460 Operator’s Manual
F-16 246-42800-01 - Aug 2013
Kelvin Equation with Broekhoff-de Boer Thickness Curve
N2 - Broekhoff-de Boer Model
The kernel function is calculated using the Broekhoff-de Boer equation with standard parameters:
The nitrogen properties used in the Kelvin equation are:
N2 - Broekhoff-de Boer Model
The calculation is similar to the above except that cylindrical geometry is assumed, and the film thick-
ness depends on pore size (see reference).
Geometry Slit
Substrate Average
Category: Porosity
Method: Nitrogen at 77 K
Surface tension =
8.88 dynes cm
-1
Molar density =
0.02887 g cm
-3
Geometry Cylinder
Substrate Average
Category: Porosity
Method: Nitrogen at 77 K
Reference: Specifically, equations 20 and 21 in: J.C.P. Broekhoff and J.H. de Boer,
“The Surface Area in Intermediate Pores,” Proceedings of the
International Symposium on Surface Area Determination, D.H. Everett,
R.H. Ottwill, eds., U.K. (1969).
p/p
0
16.11–
t
2
----------------
0.1682
0.1137
t
–
+=log