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sea anemone

(Encyclopedia)sea anemone ənĕmˈənēˌ [key], any of the relatively large, predominantly solitary polyps (see polyp and medusa) of the class Anthozoa, phylum Cnidaria. Unlike the closely related corals, these or...

Alvarez, Luis Walter

(Encyclopedia)Alvarez, Luis Walter, 1911–88, American physicist, b. San Francisco, grad. Univ. of Chicago, 1932, Ph.D. 1936. He was awarded the 1968 Nobel Prize in Physics for his discovery of a large number of r...

hail, in meteorology

(Encyclopedia)hail, precipitation in the form of pellets composed of ice or of ice and snow, occurring at any time of the year, usually during the passage of a cold front or during a thunderstorm. Small hailstones ...

synchrotron radiation

(Encyclopedia)synchrotron radiation, in physics, electromagnetic radiation emitted by high-speed electrons spiraling along the lines of force of a magnetic field (see magnetism). Depending on the electron's energy ...

osmosis

(Encyclopedia)osmosis ŏzmōˈsĭs [key], transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass. Osmosis refers only to transfer of solvent; transfer o...

electromagnetic radiation

(Encyclopedia)CE5 Electromagnetic spectrum electromagnetic radiation, energy radiated in the form of a wave as a result of the motion of electric charges. A moving charge gives rise to a magnetic field, and if ...

metallurgy

(Encyclopedia)metallurgy mĕtˈəlûrˌjē [key], science and technology of metals and their alloys. Modern metallurgical research is concerned with the preparation of radioactive metals, with obtaining metals econ...

Gestalt

(Encyclopedia)Gestalt gəshtältˈ [key] [Ger.,=form], school of psychology that interprets phenomena as organized wholes rather than as aggregates of distinct parts, maintaining that the whole is greater than the ...

animism

(Encyclopedia)animism, belief in personalized, supernatural beings (or souls) that often inhabit ordinary animals and objects, governing their existence. British anthropologist Sir Edward Burnett Tylor argued in Pr...

mixture

(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...