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actinide series

(Encyclopedia)actinide series, a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a...

astatine

(Encyclopedia)astatine ăsˈtətēn, –tĭn [key] [Gr.,=unstable], semimetallic radioactive chemical element; symbol At; at. no. 85; at. wt. of most stable isotope 210; m.p. 302℃ (estimated); b.p. 337℃ (estima...

air mass

(Encyclopedia)air mass, large body of air within the earth's atmosphere in which temperature and humidity, although varying at different heights, remain similar throughout the body at any one height. Air masses for...

Randall, Lisa

(Encyclopedia)Randall, Lisa, 1962–, American theoretical physicist and writer, b. New York City, B.A. Harvard University, 1983, Ph.D. Harvard University, 1987. Rand...

Land, Edwin Herbert

(Encyclopedia)Land, Edwin Herbert, 1909–91, American inventor and photographic pioneer. While at Harvard, Land became interested in the properties and manipulation of polarized light. He left Harvard and, in 1932...

physical chemistry

(Encyclopedia)physical chemistry, branch of science that combines the principles and methods of physics and chemistry. It provides a fundamental theoretical and experimental basis for all of chemistry, including or...

ceramics

(Encyclopedia)ceramics sərămˈĭks [key], materials made of nonmetallic minerals that have been permanently hardened by firing at a high temperature, or objects made of such materials. Most ceramics resist heat a...

cladistics

(Encyclopedia)cladistics fīˌlōjənĕtˈĭk [key], an approach to the classification of living things in which organisms are defined and grouped by the possession of one or more shared characteristics (called cha...

Levi, Primo

(Encyclopedia)Levi, Primo prēˈmō lāˈvē [key], 1919–87, Italian writer. A chemist of Jewish descent, Levi was sent to the concentration camp at Auschwitz during World War II. His first memoir, If This Is a M...

lungfish

(Encyclopedia)lungfish, common name for any of a group of fish belonging to the families Ceratodontidae, Lepidosirenidae, and Protopteridae, found in the rivers of Australia, South America, and Africa, respectively...
 

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