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dew

(Encyclopedia)dew, thin film of water that has condensed on the surface of objects near the ground. Dew forms when radiational cooling of these objects during the nighttime hours also cools the shallow layer of ove...

vacuum cleaner

(Encyclopedia)vacuum cleaner, mechanical device using a draft of air to remove dust, loose dirt, or other particulate matter from dry surfaces. It is especially useful on highly textured surfaces, such as carpets a...

Holm, Jeanne Marjorie

(Encyclopedia)Holm, Jeanne Marjorie, 1921–2010, U.S. military officer, the first female general in the U.S. air force, b. Portland, Oreg. Enlisting in the Women's Army Auxiliary Corps in 1942, she soon joined (19...

smog

(Encyclopedia)smog smŏg [key] [smoke+fog], dense, visible air pollution. Smog is commonly of two types. The gray smog of older industrial cities like London and New York derives from the massive combustion of coal...

kilogram

(Encyclopedia)kilogram, abbr. kg, fundamental unit of mass in the metric system, defined as the mass of the International Prototype Kilogram, a platinum-iridium cylinder kept at Sèvres, France, near Paris. Copies ...

Myers, Richard Bowman

(Encyclopedia)Myers, Richard Bowman, 1942–, American Air Force general, b. Kansas City, Mo. He studied at Kansas State Univ., graduating and joining the Air Force in 1965; he later attended Auburn Univ. (M.A., 19...

Yost, Ed

(Encyclopedia)Yost, Ed (Paul Edward Yost), 1919–2007, American balloonist, b. Bristow, Iowa, grad. Boeing School of Aeronautics, 1940. The father of modern hot-air ballooning, Yost pioneered the used of propane (...

pneumatic tool

(Encyclopedia)pneumatic tool no͝omătˈĭk [key], instrument activated by air pressure. Pneumatic tools are designed around three basic devices: the air cylinder, the vane motor, and the sprayer. The air cylinder ...

americium

(Encyclopedia)americium ămərĭˈshēəm [key], artificially produced radioactive chemical element; symbol Am; at. no. 95; mass no. of most stable isotope 243; m.p. about 1,175℃; b.p. about 2,600℃; sp. gr. 13....

bismuth

(Encyclopedia)bismuth bĭzˈməth [key] [Ger. Weisse Masse=white mass], metallic chemical element; symbol Bi; at. no. 83; at. wt. 208.98040; m.p. 271.3℃; b.p. about 1,560℃; sp. gr. 9.75 at 20℃; valence +3 or ...