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Porosimetry is an analytical technique used to determine various quantifiable aspects of a material's porous structure, such as pore diameter, total pore volume, surface area, and bulk and absolute densities. The technique involves the intrusion of a non-wetting liquid (often mercury) at high pressure into a material through the use of a ...
In the derivation of Washburn's equation, the inertia of the liquid is ignored as negligible. This is apparent in the dependence of length to the square root of time, , which gives an arbitrarily large velocity dL/dt for small values of t.
In capillary flow porometry, in opposition to mercury intrusion porosimetry, the wetting liquid enters spontaneously the pores of the sample ensuring a total wetting of the material, and therefore the contact angle of the wetting liquid with the sample is 0 and the previous formula can be simplified as: P= 4*γ/D.
The vapor pressure at a convex curved surface is higher than that at a flat surface. The Kelvin equation is dependent upon thermodynamic principles and does not allude to special properties of materials. It is also used for determination of pore size distribution of a porous medium using adsorption porosimetry.
Micro CT of porous medium: Pores of the porous medium shown as purple color and impermeable porous matrix shown as green-yellow color. Pore structure is a common term employed to characterize the porosity, pore size, pore size distribution, and pore morphology (such as pore shape, surface roughness, and tortuosity of pore channels) of a porous medium.
The equation first formulated a means to calculate cumulative surface areas of porous solids based on data taken in mercury porosimetry testing. Rootare and Spencer later devised a computer program to carry out automated calculations, "A Computer Program for Pore Volume and Pore Area Distribution," Rootare & Spencer, Perspectives in Powder ...
BET model of multilayer adsorption, that is, a random distribution of sites covered by one, two, three, etc., adsorbate molecules. The concept of the theory is an extension of the Langmuir theory, which is a theory for monolayer molecular adsorption, to multilayer adsorption with the following hypotheses:
[10] [11] This is in effect an "ice intrusion" measurement (c.f. Mercury Intrusion Porosimetry), and as such in part may provide information on pore throat properties. The melting event was then previously expected to provide more accurate information on the pore body.