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ampere

(Encyclopedia)ampere ămˈpēr [key], abbr. amp or A, basic unit of electric current. It is the fundamental electrical unit used with the mks system of units of the metric system. The ampere is officially defined a...

Galvani, Luigi

(Encyclopedia)Galvani, Luigi lo͞oēˈjē gälväˈnē [key], 1737–98, Italian physician. He was professor of anatomy from 1775 at the Univ. of Bologna and was noted as a surgeon and for research in comparative a...

Foucault, Jean Bernard Léon

(Encyclopedia)Foucault, Jean Bernard Léon zhäN bĕrnärˈ lāôNˈ fo͞okōˈ [key], 1819–68, French physicist. Known especially for his research on the speed of light, he determined its velocity in air and fou...

coagulation

(Encyclopedia)coagulation kōăgˌyo͞olāˈshən [key], the collecting into a mass of minute particles of a solid dispersed throughout a liquid (a sol), usually followed by the precipitation or separation of the s...

Fiske, Bradley Allen

(Encyclopedia)Fiske, Bradley Allen fĭsk [key], 1854–1942, American naval officer and inventor, b. Lyons, N.Y., grad. Annapolis, 1874. In the U.S. navy he devoted himself to the invention of instruments for shipb...

Siemens, Sir William

(Encyclopedia)Siemens, Sir William, 1823–83, English electrical engineer, b. Germany; brother of Ernst Werner von Siemens. Originally his name was Carl Wilhelm Siemens. After visiting England to introduce an elec...

silicon carbide

(Encyclopedia)silicon carbide, chemical compound, SiC, that forms extremely hard, dark, iridescent crystals that are insoluble in water and other common solvents. Widely used as an abrasive, it is marketed under su...

quinidine

(Encyclopedia)quinidine kwĭnˈĭdēnˌ [key], heart muscle relaxant used to maintain regular heart rhythm patterns. It is an alkaloid chemically similar to quinine and, like quinine, occurs naturally in some speci...

Volta, Alessandro, Conte

(Encyclopedia)Volta, Alessandro, Conte älĕs-sänˈdrō kônˈtā vôlˈtä [key], 1745–1827, Italian physicist. He was professor of physics at the Univ. of Pavia from 1779 and became famous for his work in elec...

Van Halen, Eddie

(Encyclopedia)Van Halen, Eddie (Edward Lodewijk Van Halen), 1955–2020, American rock musician and song writer, b. Amsterdam, Netherlands; his family moved to California when he was young. He and brother Alex form...