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sweat

(Encyclopedia)sweat or perspiration, fluid secreted by the sweat glands of mammalian skin and containing water, salts, and waste products of body metabolism such as urea. The dissolved solid content of sweat is onl...

platinite

(Encyclopedia)platinite, alloy that is 46% nickel and 54% iron. It is used in the manufacture of electric lightbulbs because its coefficient of expansion, i.e., the rate at which its volume increases with temperatu...

Lee, David Morris

(Encyclopedia)Lee, David Morris, 1931–, American physicist, b. Rye, N.Y., Ph.D. Yale, 1959. Lee joined the faculty at Cornell in 1959, moving to Texas A&M Univ. in 2009. He was a co-recipient, with Douglas Os...

hydrogenation

(Encyclopedia)hydrogenation hīdrôjˈənāˌshən, hīˌdrəjənāˈshən [key], chemical reaction of a substance with molecular hydrogen, usually in the presence of a catalyst. A common hydrogenation is the harde...

eye bank

(Encyclopedia)eye bank, site for the collection, processing, and assignment of donated eyes. A donor's eyes are removed as soon as possible after death, sealed in a sterile container, and sent to the eye bank. Ther...

radiosonde

(Encyclopedia)radiosonde rāˈdēōsŏnd [key], group of instruments for simultaneous measurement and radio transmission of meteorological data, including temperature, pressure, and humidity of the atmosphere. The ...

stellar structure

(Encyclopedia)stellar structure, physical properties of a star and the processes taking place within it. Except for that of the sun, astronomers must draw their conclusions regarding stellar structure on the basis ...

electret

(Encyclopedia)electret, solid electrically insulating, or dielectric, material that has acquired a long-lasting electrostatic polarization. Electrets are produced by heating certain dielectric materials to a high t...

luminosity

(Encyclopedia)luminosity, in astronomy, the rate at which energy of all types is radiated by an object in all directions. A star's luminosity depends on its size and its temperature, varying as the square of the ra...

Hansen, James Edward

(Encyclopedia)Hansen, James Edward, 1941–, American astrophysicist and climatologist, b. Denison, Iowa, Ph.D. Univ. of Iowa, 1967. In 1967 he joined the Goddard Institute for Space Studies, and served as director...