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hurricane

(Encyclopedia)CE5 View into the eye of a hurricane showing the structure of the surrounding cloud wall hurricane, tropical cyclone in which winds attain speeds greater than 74 mi (119 km) per hr. Wind speeds gu...

poison

(Encyclopedia)poison, any agent that may produce chemically an injurious or deadly effect when introduced into the body in sufficient quantity. Some poisons can be deadly in minute quantities, others only if relati...

ventilation

(Encyclopedia)ventilation, process of supplying fresh air to an enclosed space and removing from it air contaminated by odors, gases, or smoke. Proper ventilation requires also that there be a movement or circulati...

superconductivity

(Encyclopedia)superconductivity, abnormally high electrical conductivity of certain substances. The phenomenon was discovered in 1911 by Heike Kamerlingh Onnes, who found that the resistance of mercury dropped sudd...

hydrogen bomb

(Encyclopedia)hydrogen bomb or H-bomb, weapon deriving a large portion of its energy from the nuclear fusion of hydrogen isotopes. In an atomic bomb, uranium or plutonium is split into lighter elements that togethe...

Sahara

(Encyclopedia)Sahara səhârˈə [key] [Arab.,=desert], world's largest desert, c.3,500,000 sq mi (9,065,000 sq km), N Africa; the western part of a great arid zone that continues into SW Asia. Extending more than ...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

circulatory system

(Encyclopedia)CE5 Circulatory system circulatory system, group of organs that transport blood and the substances it carries to and from all parts of the body. The circulatory system can be considered as compose...

nephritis

(Encyclopedia)nephritis nəfrīˈtəs [key], inflammation of the kidney. The earliest finding is within the renal capillaries (glomeruli); interstitial edema is typically followed by interstitial infiltration of ly...

Oder-Neisse line

(Encyclopedia)Oder-Neisse line, frontier established in 1945 between Germany and Poland; it followed the Oder and W Neisse rivers from the Baltic Sea to the Czechoslovak border. The boundary, desired by most Poles ...