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electron

(Encyclopedia)electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the ...

manganese

(Encyclopedia)manganese măngˈgənēs, mănˈ– [key] [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244℃; b.p. about 1,962℃; sp. gr. 7.2 to 7.45, depending o...

retrograde motion

(Encyclopedia)retrograde motion, in astronomy, real or apparent movement of a planet, dwarf planet, moon, asteroid, or comet from east to west relative to the fixed stars. The most common direction of motion in the...

venom

(Encyclopedia)venom or zootoxin, any of a variety of poisonous substances produced by animals. In poisonous snakes, venom is secreted in two poison glands, one on each side of the upper jaw, and enters the fang by ...

dissociation

(Encyclopedia)dissociation, in chemistry, separation of a substance into atoms or ions. Thermal dissociation occurs at high temperatures. For example, hydrogen molecules (H2) dissociate into atoms (H) at very high ...

roentgenium

(Encyclopedia)roentgenium, artificially produced radioactive chemical element; symbol Rg; at. no. 111; mass number of most stable isotope 280; m.p., b.p., sp. gr., and valence unknown. Situated in Group 11 of the p...

stock, in finance

(Encyclopedia)stock, in finance, instrument certifying to shares in the ownership of a corporation. Bonds are similar evidences of shares in a loan to a corporation. Stock yields no dividends until claims of bondho...

bonobo

(Encyclopedia)bonobo, smaller of two species of chimpanzee, genus Pan. Whereas the common chimpanzee, P. troglodytes, lives in forests across most of equatorial Africa, the bonobo, P. paniscus (sometimes called the...

von Klitzing, Klaus

(Encyclopedia)von Klitzing, Klaus, 1943–, German physicist, Ph.D. Univ. of Würzburg, 1972. He was a professor at the Technical Univ. of Munich (1980–85) and then director of the Max Planck Institute for Solid ...

perturbation

(Encyclopedia)perturbation pŭrˌtərbāˈshən [key], in astronomy and physics, small force or other influence that modifies the otherwise simple motion of some object. The term is also used for the effect produce...