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dialysis

(Encyclopedia)dialysis dīălˈĭsĭs [key], in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of t...

covenant

(Encyclopedia)covenant kŭvˈənənt [key], agreement entered into voluntarily by two or more parties to do or refrain from doing certain acts. In the Bible and in theology the covenant is the agreement or engageme...

chain reaction

(Encyclopedia)CE5 Chain reaction: A neutron (n) strikes the uranium nucleus (U-235), causing it to split into fission products A and B and release two neutrons. These neutrons can in turn cause further fissions....

etching

(Encyclopedia)etching, the art of engraving with acid on metal; also the print taken from the metal plate so engraved. In hard-ground etching the plate, usually of copper or zinc, is given a thin coating or ground ...

embryo screening

(Encyclopedia)embryo screening, procedure (see genetic testing) in which a single cell is removed from an embryo two or three days after it has been conceived through in vitro fertilization and tested for genetic a...

spring, in geology

(Encyclopedia)spring, in geology, natural flow of water from the ground or from rocks, representing an outlet for the water that has accumulated in permeable rock strata underground. Some of the water that falls as...

Allais, Maurice Félix Charles

(Encyclopedia)Allais, Maurice Félix Charles môrēsˈ shärl älĕˈ [key], 1911–2010, French economist, Ph.D. Univ. of Paris, 1949. After working in the French mine administration, he joined the École National...

cross-laminated timber

(Encyclopedia)cross-laminated timber (CLT), manufactured wood panels that consist of layers of boards glued together under pressure with the grain of the boards in one layer running perpendicular to the grain in ad...

copperhead

(Encyclopedia)copperhead, poisonous snake, Ancistrodon contortrix, of the E United States. Like its close relative, the water moccasin, the copperhead is a member of the pit viper family and detects its warm-bloode...

Constantine I, king of Greece

(Encyclopedia)Constantine I, 1868–1923, king of the Hellenes, eldest son of George I, whom he succeeded in 1913. Married to Sophia, sister of the German emperor William II, he opposed the pro-Allied policy of the...