The air permeability specific surface of a powder material is a single-parameter measurement of the fineness of the powder. The specific surface is derived from the resistance to flow of air (or some other gas) through a porous bed of the powder. The SI units are m2·kg−1 ("mass specific surface") or m2·m−3 ("volume specific surface").
Read more about Air Permeability Specific Surface: Significance, Methods
Famous quotes containing the words air, specific and/or surface:
“People fall out of windows, trees tumble down,
Summer is changed to winter, the young grow old
The air is full of children, statues, roofs
And snow. The theatre is spinning round,
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The most massive sopranos are singing songs of scales.”
—Wallace Stevens (1879–1955)
“The more specific idea of evolution now reached is—a change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter.”
—Herbert Spencer (1820–1903)
“When we are in love, the sentiment is too great to be contained whole within us; it radiates out to our beloved, finds in her a surface which stops it, forces it to return to its point of departure, and it is this rebound of our own tenderness which we call the other’s affection and which charms us more than when it first went out because we do not see that it comes from us.”
—Marcel Proust (1871–1922)