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Stark, Johannes

(Encyclopedia)Stark, Johannes, 1874–1957, German physicist, Ph.D. Univ. of Munich, 1897. From 1900 until he retired in 1922, Stark served short stints on the faculties of several academic institutions, including ...

electric shock

(Encyclopedia)electric shock, effect of the passage of a current of electricity through the body. Fatality may result from shocks of from 1 to 2 amperes and 500 to 1,000 volts. However, the effect of electric shock...

spintronics

(Encyclopedia)spintronics, spin electronics, or magnetoelectronics, science and technology that harnesses the spin state of electrons in addition to the electrical charge state to store data or perform calculation...

hydroplane

(Encyclopedia)hydroplane, small, high-powered racing boat designed to skim along the surface of the water. Its hull is so shaped that at high speeds the bow is tilted up out of the water, reducing the effect of fri...

nonintercourse

(Encyclopedia)nonintercourse, in international law, refusal of a state to engage in diplomatic or commercial relations with another state. It is a hostile act of retaliation for some wrong and is intended to effect...

control systems

(Encyclopedia)control systems, combinations of components (electrical, mechanical, thermal, or hydraulic) that act together to maintain actual system performance close to a desired set of performance specifications...

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...

North American Free Trade Agreement

(Encyclopedia)North American Free Trade Agreement (NAFTA), accord establishing a free-trade zone in North America; it was signed in 1992 by Canada, Mexico, and the United States and took effect on Jan. 1, 1994. NAF...

hygrometer

(Encyclopedia)hygrometer hīgrŏmˈətər [key], instrument used to measure the moisture content of a gas, as in determining the relative humidity of air. The temperature at which dew or frost forms is a measure of...

cesium

(Encyclopedia)cesium sēˈzēəm [key] [Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.90545; m.p. 28.4℃; b.p. 669.3℃; sp. gr. 1.873 at 20℃; valence +1. Cesium is a ductil...