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curium

(Encyclopedia)curium kyo͝orˈēəm [key], artificially produced radioactive chemical element; symbol Cm; at. no. 96; mass no. of most stable isotope 247; m.p. about 1,340℃; b.p. 3,110℃; sp. gr. 13.5 (calculate...

code, in communications

(Encyclopedia)code, in communications, set of symbols and rules for their manipulation by which the symbols can be made to carry information. By this extended definition all written and spoken languages are codes. ...

personal computer

(Encyclopedia)personal computer (PC), small but powerful computer primarily used in an office or home without the need to be connected to a larger computer. PCs evolved after the development of the microprocessor m...

electoral college

(Encyclopedia)electoral college, in U.S. government, the body of electors that chooses the president and vice president. The Constitution, in Article 2, Section 1, provides: “Each State shall appoint, in such Man...

chain reaction

(Encyclopedia)CE5 Chain reaction: A neutron (n) strikes the uranium nucleus (U-235), causing it to split into fission products A and B and release two neutrons. These neutrons can in turn cause further fissions....

nullification

(Encyclopedia)nullification, in U.S. history, a doctrine expounded by the advocates of extreme states' rights. It held that states have the right to declare null and void any federal law that they deem unconstituti...

tape recorder

(Encyclopedia)CE5 Magnetic tape-recording system tape recorder, device for recording and replaying of sound, video, and digital information on plastic (usually polyester) or paper tape. The tape is coated with ...

electronic game

(Encyclopedia)electronic game, device or computer program that provides entertainment by challenging a person's eye-hand coordination or mental abilities. Made possible by the development of the microprocessor, ele...

digital versatile disc

(Encyclopedia)digital versatile disc or digital video disc (DVD), a small plastic disc used for the storage of digital data. The successor media to the compact disc (CD), a DVD can have more than 100 times the stor...

e-commerce

(Encyclopedia)e-commerce, commerce conducted over the Internet, most often via the World Wide Web. E-commerce can apply to purchases made through the Web or to business-to-business activities such as inventory tran...