An Etymological Dictionary of Astronomy and Astrophysics

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فرهنگ ریشه‌شناختی اخترشناسی-اخترفیزیک

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porosity
  پرلیکی  
porliki
Fr.: porosité  

  1. General: A → dimensionless number characterizing a porous medium, expressed by the ratio of the volume occupied by the pores to the total volume of the medium.

  2. Geology: The percentage volume of hollow spaces in a rock, sediment, or soil.

  3. Dust grains: The quantity usually defined as:

P = (Vv/Vt) = (1 - Vs/Vt), where Vv and Vs are the volumes of vacuum and of the solid matter making up the particle, and Vt is the total volume of the particle within some defined surface.

See also: → porous; → -ity.