Talk:Porosity

Nanoporous Materials
Where is the section on nanoporous materials (zeolites, activated carbon and so on)??? Its a shocking absence! 130.195.86.38 10:13, 11 May 2007 (UTC)Spikeyi

I agree that these should be mentioned. Also, the nanopores in volcanic ash have some implications for the ways in which porosity in sediments is measured and how quickly these sediments are altered. Unfortunately, I don't have any free and open sources from which to write this section at the moment. It's on my to-do list unless someone else does it first.Elriana (talk) 21:56, 20 December 2013 (UTC)

Measuring Porosity
This section needs attention. It is written as a basic how to manual. Suggest leaving only types of methods and removing explanations. I will leave as is for now, but will return later to amend. Halogenated (talk) 03:05, 7 December 2007 (UTC)


 * Done. Also removed irrelevant info on porosity in manufacturing.

Porality?
I have not heard of porality before, and it did not reveal any good google matches either. It might be a WP:NEOLOGISM, in any case, unless it can be sufficiently referenced, it has to be removed. --Berland (talk) 12:12, 18 July 2009 (UTC)
 * No comments here, so I am removing the paragraph. --Berland (talk) 18:35, 23 July 2009 (UTC)

Optical methods for determining porosity
Optical methods (e.g., determining the area of the material versus the area of the pores visible under the microscope)

In this case, is the porosity measured on the section $$ \phi_A = A_v/A_t $$ equal to the porosity of the volume $$ \phi_V = V_v/V_t $$, or do the different spacial dimensions have to be accounted for by raising $$ \phi_A $$ to the power 1.5.

That is, is
 * $$ \phi_V = \phi_A $$

or is
 * $$ \phi_V = \phi_A^{1.5}. $$

As in the article, $$ V_t, V_v $$ are the total and the pore volume, respectively. Accordingly, $$ A_t, A_v $$ are the total cross section area and the cross section area of the pores. T om ea s y T C 07:24, 24 July 2009 (UTC)


 * As you note, the symbols in the equation for the gas expansion method may need to be changed (to bring in in line with the rest of the article).
 * The areal and volumetric porosities are equal, I (hopefully) clarified this in the article--sorry I have missed it. Stan J. Klimas (talk) 11:29, 24 July 2009 (UTC)
 * Thanks for your quick response.
 * I did not mean to comment on the notation used in the article. I simply tried to use a notation similar to the first equation in the article. If this triggered some improvement pertaining to the gas expansion method, I am happy.
 * My only concern was the optical method. You made the statement very clear now. However, are you sure that this is correct? Or how can you justify this? At least we must assume that the cross section is representative for all possible cross sections, I think. Under this assumption, I think you are right, but I also have doubts. I'll try to explain my doubting reasoning.
 * Think of two discs with surface areas A1 and A2 = 0.01*A1, where A1 is the surface area of a cut through a sphere and A2 is the surface area of a pore in the sphere. In this case, the corresponding volumes are related by V2 = 0.01^1.5*V1.
 * I guess there is something wrong in this line of thought, but I am lacking a clear cut reasoning why things are as simple as the article says after your correction. T om ea s y T C 19:00, 24 July 2009 (UTC)


 * To the statement in the article, I added a reference (Dullien) that summarizes the solution (page 7) as follows:
 * The issue of interdependence of volumetric, areal, and linear porosities is discussed in more detail here. Hope this helps!  Best regards, Stan J. Klimas (talk) 14:42, 25 July 2009 (UTC)
 * Thanks a lot for helping me and improving the article. T om ea s y T C 19:20, 25 July 2009 (UTC)