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Lanzhou

(Encyclopedia)Lanzhou or Lanchow both: länˈjōˈ [key], city (1994 est. pop. 1,295,600), capital of Gansu prov., W China, on the Huang He (Yellow River) at its confluence with the Wei. It is a rail, highway, and ...

Soddy, Frederick

(Encyclopedia)Soddy, Frederick sŏdˈē [key], 1877–1956, English chemist. He worked under Lord Rutherford at McGill Univ. and with Sir William Ramsay at the Univ. of London. After serving (1910–14) as lecturer...

radiation

(Encyclopedia)radiation rāˌdēāˈshən [key], term applied to the emission and transmission of energy through space or through a material medium and also to the radiated energy itself. In its widest sense the te...

uncertainty principle

(Encyclopedia)uncertainty principle, physical principle, enunciated by Werner Heisenberg in 1927, that places an absolute, theoretical limit on the combined accuracy of certain pairs of simultaneous, related measur...

quantum theory

(Encyclopedia)quantum theory, modern physical theory concerned with the emission and absorption of energy by matter and with the motion of material particles; the quantum theory and the theory of relativity togethe...

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 ...

ozone

(Encyclopedia)ozone ōˈzōn [key], an allotropic form of the chemical element oxygen (see allotropy). Pure ozone is an unstable, faintly bluish gas with a characteristic fresh, penetrating odor. The gas has a dens...

spectrum

(Encyclopedia)CE5 Dispersion of white light by a triangular prism spectrum, arrangement or display of light or other form of radiation separated according to wavelength, frequency, energy, or some other propert...

nuclear reactor

(Encyclopedia)CE5 Power reactor system nuclear reactor, device for producing controlled release of nuclear energy. Reactors can be used for research or for power production. A research reactor is designed to pr...

Michigan, University of

(Encyclopedia)Michigan, University of, main campus at Ann Arbor; state supported; coeducational; chartered 1817 at Detroit as the Catholepistemiad, or Univ., of Michigania, rechartered 1821 (as Univ. of Mich.) and ...