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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...

carbon black

(Encyclopedia)carbon black, mixture of partially burned hydrocarbons. Carbon black is produced by partial combustion of natural gas. It is used as a black pigment for inks and paints, and is used in large amounts b...

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...

solar energy

(Encyclopedia)solar energy, any form of energy radiated by the sun, including light, radio waves, and X rays, although the term usually refers to the visible light of the sun. Solar energy is needed by green plants...

engine

(Encyclopedia)engine: see diesel engine; internal-combustion engine; steam engine; rotary engine; automobile. ...

Berthollet, Claude Louis, Comte

(Encyclopedia)Berthollet, Claude Louis, Comte klōd lwē, kôNt bĕrtōlāˈ [key], 1748–1822, French chemist. His contributions to chemistry include the analysis of ammonia and prussic acid and the discovery of ...