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radioimmunoassay
(Encyclopedia)radioimmunoassay (RIA), highly sensitive laboratory technique used to measure minute amounts of substances including antigens, hormones, and drugs present in the body. The substance or antigen (a fore...ray, in physics
(Encyclopedia)ray, in physics, term denoting the straight line along which light or other form of radiation is propagated from its source. It generally refers to the line of propagation of waves but is also applied...radium
(Encyclopedia)radium rāˈdēəm [key] [Lat. radius=ray], radioactive metallic chemical element; symbol Ra; at. no. 88; mass number of most stable isotope 226; m.p. 700℃; b.p. 1,140℃; sp. gr. about 6.0; valence...Hahn, Otto
(Encyclopedia)Hahn, Otto ôˈtō hän [key], 1879–1968, German chemist and physicist. His important contributions in the field of radioactivity include the discovery of several radioactive substances, the develop...Paneth, Friedrich Adolf
(Encyclopedia)Paneth, Friedrich Adolf frēˈdrĭkh äˈdôlf päˈnĕt [key], 1887–1958, Austrian chemist. He was educated at Vienna, Munich, and Glasgow. He held a number of teaching posts in Germany until he wa...ionization chamber
(Encyclopedia)ionization chamber, device for the detection and measurement of ionizing radiation. It consists basically of a sealed chamber containing a gas and two electrodes between which a voltage is maintained ...Geiger, Johannes Wilhelm
(Encyclopedia)Geiger, Johannes Wilhelm (Hans Geiger) gīˈgər [key], 1882–1945, German physicist. Geiger received a doctorate in physics at Erlangen in 1906, then went to Manchester, where he assisted British c...Bikini
(Encyclopedia)Bikini bēkēˈnē [key], atoll, c.2 sq mi (5.2 sq km), W central Pacific, one of the Ralik Chain, Marshall Islands. It comprises 36 islets on a reef 25 mi (40 km) long. After its inhabitants were rem...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...scintillation counter
(Encyclopedia)scintillation counter, device for detecting and measuring radiation by means of tiny visible flashes produced by the radiation when it strikes a sensitive substance known as a phosphor (see phosphores...Browse by Subject
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