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technetium
(Encyclopedia)technetium tĕknēˈshēəm [key] [Gr. technetos=artificial], artificially produced radioactive chemical element; symbol Tc; at. no. 43; mass no. of most stable isotope 98; m.p. 2,200℃; b.p. 4,877...moscovium
(Encyclopedia)moscovium mŏskōˈvēəm [key], artificially produced radioactive chemical element; symbol Mc; at. no. 115; mass number of most stable isotope 288; m.p., b.p., sp. gr., and valence unknown. Situated ...water power
(Encyclopedia)water power, mechanical energy derived from falling or flowing water, e.g., rivers, streams, and the overflow of dams. The wooden water wheel, long utilized for driving machinery in flour mills and fa...transuranium elements
(Encyclopedia)transuranium elements, in chemistry, radioactive elements with atomic numbers greater than that of uranium (at. no. 92). All the transuranium elements of the actinide series were discovered as synthet...electron
(Encyclopedia)electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the ...Tudor
(Encyclopedia)Tudor, royal family that ruled England from 1485 to 1603. Its founder was Owen Tudor, of a Welsh family of great antiquity, who was a squire at the court of Henry V and who married that king's widow, ...Ontario, province, Canada
(Encyclopedia) CE5 Ontario ŏntârˈēō [key], province (2001 pop. 11,410,046), 412,582 sq mi (1,068,587 sq km), E central Canada. Before the arrival of Europeans the Ontario region was inhabited by several Al...Hejaz
(Encyclopedia)Hejaz or Hedjaz both: hējăzˈ, hĕjäzˈ [key], region, c.150,000 sq mi (388,500 sq km), NW Saudi Arabia, on the Gulf of Aqaba and the Red Sea. Mecca is the chief city. Extending S to Asir, Hejaz is...Cistercians
(Encyclopedia)Cistercians sĭstrˈshənz [key], monks of a Roman Catholic religious order founded (1098) by St. Robert, abbot of Molesme, in Cîteaux [Cistercium], Côte-d'Or dept., France. They reacted against Clu...Seaborg, Glenn Theodore
(Encyclopedia)Seaborg, Glenn Theodore sēˈbôrg [key], 1912–99, American chemist, b. Ishpeming, Mich., grad. Univ. of California at Los Angeles, 1934, Ph.D. Univ. of California at Berkeley, 1937. In 1939, he beg...Browse by Subject
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