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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...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....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...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...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...license
(Encyclopedia)license, in public law, permission by legal authority to engage in certain acts and also the document showing such permission. Some licenses are required for the protection of the public; they assure ...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...Hastings, city, England
(Encyclopedia)Hastings, city and district, East Sussex, SE England. A resort and residential city, Hastings is backed by cliffs and has a 3-mi (4.8-km) marine esplana...half-life
(Encyclopedia)half-life, measure of the average lifetime of a radioactive substance (see radioactivity) or an unstable subatomic particle. One half-life is the time required for one half of any given quantity of th...Browse by Subject
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