This expression assumes the capillary phenomenon occurs within a tube with a circular cross section. Real pores only approximate this, and then only if they are intergranular or intercrystalline (Coalson, personal communication, 1997).
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This expression assumes the capillary phenomenon occurs within a tube with a circular cross section. Real pores only approximate this, and then only if they are intergranular or inter crystalline (<ref name=CoalsonPC>Coalson, personal communication, 1997</ref>).