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Chernobyl

(Encyclopedia)Chernobyl chĭrnōˈbyēl [key], Ukr. Chornobyl, abandoned city, N Ukraine, near the Belarus border, on the Pripyat River. Ten miles (16 km) to the north, in the town of Pripyat, is the Chernobyl nucl...

gamma radiation

(Encyclopedia)gamma radiation, high-energy photons emitted as one of the three types of radiation resulting from natural radioactivity. It is the most energetic form of electromagnetic radiation, with a very short ...

neutron star

(Encyclopedia)neutron star, extremely small, extremely dense star, with as much as double the sun's mass but only a few miles in radius, in the final stage of stellar evolution. Astronomers Baade and Zwicky predict...

radio range

(Encyclopedia)radio range, geographically fixed radio transmitter that radiates coded signals in all directions to enable aircraft and ships to determine their bearings. An aircraft or ship can determine its line o...

Laval, Pierre

(Encyclopedia)Laval, Pierre lävälˈ [key], 1883–1945, French politician. Elected (1914) to the chamber of deputies as a Socialist, he held various cabinet posts and in 1926 became a senator as an Independent, ...

duck

(Encyclopedia)duck, common name for wild and domestic waterfowl of the family Anatidae, which also includes geese and swans. It is hunted and bred for its meat, eggs, and feathers. Strictly speaking, duck refers to...

neural network

(Encyclopedia)neural network or neural computing, computer architecture modeled upon the human brain's interconnected system of neurons. Neural networks imitate the brain's ability to sort out patterns and learn fr...

cystitis

(Encyclopedia)cystitis sĭstīˈtĭs [key], common acute or chronic inflammation of the urinary bladder. The disease occurs primarily in young women and frequently results from bacterial invasion of the urethra fro...

phenothiazine

(Encyclopedia)phenothiazine fēˌnəthīˈəzĭn [key], any one of a class of drugs used to control mental disorders. Phenothiazines, along with other antipsychotic, or neuroleptic, drugs are used for such disorder...

ultrasonics

(Encyclopedia)ultrasonics, study and application of the energy of sound waves vibrating at frequencies greater than 20,000 cycles per second, i.e., beyond the range of human hearing. The application of sound energy...