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conduction

(Encyclopedia)conduction, transfer of heat or electricity through a substance, resulting from a difference in temperature between different parts of the substance, in the case of heat, or from a difference in elect...

Mayer, Julius Robert von

(Encyclopedia)Mayer, Julius Robert von, 1814–78, German physician and physicist, studied medicine at Tübingen, Munich, and Paris. From a consideration of the generation of animal heat, he was led to determine th...

cramp

(Encyclopedia)cramp, painful uncontrollable contraction of a muscle or group of muscles. The type that results from cold, strain, or disturbance of circulation (as experienced by swimmers) is eased by massage and t...

hardening

(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...

wind chill

(Encyclopedia)wind chill, the cooling effect of wind and temperature combined, expressed in terms of the effect produced by a lower, windless temperature, also called wind chill factor, wind chill temperature, wind...

vulcanization

(Encyclopedia)vulcanization vŭlˌkənəzāˈshən [key], treatment of rubber to give it certain qualities, e.g., strength, elasticity, and resistance to solvents, and to render it impervious to moderate heat and c...

convection

(Encyclopedia)convection, mode of heat transfer in fluids (liquids and gases). Convection depends on the fact that, in general, fluids expand when heated and thus undergo a decrease in density (since a given volume...

Melloni, Macedonio

(Encyclopedia)Melloni, Macedonio mächādôˈnyō māl-lōˈnē [key], 1798–1854, Italian physicist. Known especially for his investigations of heat, he pointed out the similarity of heat to light, showing that i...

Black, Joseph

(Encyclopedia)Black, Joseph, 1728–99, Scottish chemist and physician, b. France. He was professor of chemistry at Glasgow (1756–66) and from 1766 at Edinburgh. He is best known for his theories of latent heat a...

thermography

(Encyclopedia)thermography thûrˌmŏgˈrəfē [key], contact photocopying process that produces a direct positive image and in which infrared rays are used to expose the copy paper. In a specially designed machine...