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rectifier

(Encyclopedia)rectifier, component of an electric circuit used to change alternating current to direct current. Rectifiers are made in various forms, all operating on the principle that current passes through them ...

Proclus

(Encyclopedia)Proclus prōˈkləs [key], 410?–485, Neoplatonic philosopher, b. Constantinople. He studied at Alexandria and at Athens, where he was a pupil of the Platonist Syrianus, whom he succeeded as a teache...

Charles II, king of England, Scotland, and Ireland

(Encyclopedia)Charles II, 1630–85, king of England, Scotland, and Ireland (1660–85), eldest surviving son of Charles I and Henrietta Maria. Charles was a ruler of considerable political skill. His reign was m...

aerodynamics

(Encyclopedia)aerodynamics, study of gases in motion. As the principal application of aerodynamics is the design of aircraft, air is the gas with which the science is most concerned. Although aerodynamics is primar...

nationalism

(Encyclopedia)nationalism, political or social philosophy in which the welfare of the nation-state as an entity is considered paramount. Nationalism is basically a collective state of mind or consciousness in which...

electors

(Encyclopedia)electors, in the history of the Holy Roman Empire, the princes who had the right to elect the German kings or, more exactly, the kings of the Romans (Holy Roman emperors). Until the reign (1493–1519...

Logos

(Encyclopedia)Logos lōˈgŏs [key] [Gr.,=word], in Greek and Hebrew metaphysics, the unifying principle of the world. The central idea of the Logos is that it links God and man, hence any system in which the Logos...

homeopathy

(Encyclopedia)homeopathy hōmēŏpˈəthē [key], system of medicine whose fundamental principle is the law of similars—that like is cured by like. It was first given practical application by Samuel Hahnemann of ...

Calvo, Carlos

(Encyclopedia)Calvo, Carlos kärˈlōs kälˈvō [key], 1824–1906, Argentine diplomat and historian. He spent much of his life in diplomatic service abroad. He edited a collection of Latin American treaties and d...

teleportation, in physics

(Encyclopedia)teleportation, in physics, the transfer of key properties from one particle (or group of particles) to another a significant distance apart without a physical connection between the two particles (or ...