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:
“Oh, it’s home again, and home again, America for me!
I want a ship that’s westward bound to plow the rolling sea,
To the blessed Land of Room Enough beyond the ocean bars,
Where the air is full of sunlight and the flag is full of stars.”
—Henry Van Dyke (1852–1933)
“I was asking for something specific and perfect for my city,
Whereupon lo! upsprang the aboriginal name.
Now I see what there is in a name, a word, liquid, sane, unruly,
musical, self-sufficient,
I see that the word of my city is that word from of old,
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Rich, hemm’d thick all around with sailships and steamships, an
island sixteen miles long, solid-founded,”
—Walt Whitman (1819–1892)
“Here Men from The Planet Earth
First Set Foot upon The Moon
July, 1969 AD
We Came in Peace for All Mankind”
—Plaque left behind on the moon’s surface by the crew of Apollo 11.