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thermoelectricity

(Encyclopedia)thermoelectricity, direct conversion of heat into electric energy, or vice versa. The term is generally restricted to the irreversible conversion of electricity into heat described by the English phys...

Carnot, Nicolas Léonard Sadi

(Encyclopedia)Carnot, Nicolas Léonard Sadi kärnōˈ [key], 1796–1832, French physicist, a founder of modern thermodynamics; son of Lazare N. M. Carnot. His famous work on the motive power of heat (Réflexions ...

Thomson, William

(Encyclopedia)Thomson, William: see Kelvin, William Thomson, 1st Baron. ...

free energy

(Encyclopedia)free energy or Gibbs free energy, quantity derived from the relationships between heat and work studied in thermodynamics and used as a measure of the relative stability of a physical or chemical syst...

thermometer

(Encyclopedia)thermometer, instrument for measuring temperature. Galileo and Sanctorius devised thermometers consisting essentially of a bulb with a tubular projection, the open end of which was immersed in a liqui...

chemical equilibrium

(Encyclopedia)chemical equilibrium, state of balance in which two opposing reversible chemical reactions proceed at constant equal rates with no net change in the system. For example, when hydrogen gas, H2, and iod...

vortex

(Encyclopedia)vortex vôrˈtĕks [key], mass of fluid in whirling or rotary motion. To simplify the analysis, vortex motion usually describes motions in a frictionless fluid. In such cases the absence of friction w...

Réaumur, René Antoine Ferchault de

(Encyclopedia)Réaumur, René Antoine Ferchault de rāˈəmyo͝or, Fr. rənāˈ äNtwänˈ fĕrshōˈ də rāōmürˈ [key], 1683–1757, French physicist and naturalist. He invented an alcohol thermometer (1731) a...

Tait, Peter Guthrie

(Encyclopedia)Tait, Peter Guthrie, 1831–1901, Scottish physicist and mathematician. He was professor of natural philosophy at Edinburgh from 1860 and conducted important investigations in thermodynamics and the k...

stellar evolution

(Encyclopedia) CE5 The above Hertzsprung-Russell (H-R) diagram shows the track of stellar evolution for a typical star. After spending much of its life evolving toward or along the main sequence, the star becomes...
 

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