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Springs

(Encyclopedia)Springs, city, now part of Ekurhuleni metropolitan municipality, Gauteng prov., NE South Africa. It is an industrial center of the Witwatersrand, a gold- and uranium-mining region. Manufacturing has r...

neptunium

(Encyclopedia)neptunium nĕpto͞oˈnēəm [key], radioactive chemical element; symbol Np; at. no. 93; mass number of most stable isotope 237; m.p. about 640℃; b.p. 3,902℃ (estimated); sp. gr. 20.25 at 20℃; va...

radioactivity

(Encyclopedia)CE5 Effects of a magnetic field on the products of radioactivity CE5 Disintegration series: Radioactive decay of radium-226 into lead-206 radioactivity, spontaneous disintegration or decay of t...

Jáchymov

(Encyclopedia)Jáchymov yäˈkhĭmôf [key], Ger. Joachimsthal, town, NW Czech Republic, in Bohemia, in the Erzgebirge [ore mountains]. The productivity of its uranium mines, once extensive, has declined since Worl...

Prince Albert

(Encyclopedia)Prince Albert, city (1991 pop. 34,181), central Sask., Canada, on the North Saskatchewan River. Prince Albert is a commercial and distribution center for a lumbering, gold- and uranium-mining, and mix...

Gallup

(Encyclopedia)Gallup, town (2020 pop. 21,899), alt. 6,515 ft (1,986 m), seat of McKinley co., NW N.Mex., on the Puerco River near the Ariz. line; inc. 1891. It is a r...

Szilard, Leo

(Encyclopedia)Szilard, Leo sĭˈlärd [key], 1898–1964, American nuclear physicist and biophysicist, born in Hungary. He was educated at the Budapest Institute of Technology and the Univ. of Berlin, receiving a d...

Khan, Abdul Qadeer

(Encyclopedia)Khan, Abdul Qadeer (A. Q. Khan), 1936–, Pakistani metallurgical engineer, often called the father of Pakistan's atomic bomb, b. Bhopal, India. He moved (1952) to Pakistan and studied at the D. J. Sc...

actinium

(Encyclopedia)actinium ăktĭnˈēəm [key] [Gr.,=like a ray], radioactive chemical element; symbol Ac; at. no. 89; mass number of most stable isotope 227; m.p. about 1,050℃; b.p. 3,200℃±300℃; sp. gr. 10.07;...

protactinium

(Encyclopedia)protactinium prōˌtăktĭnˈēəm [key], radioactive chemical element; symbol Pa; at. no. 91; mass number of most stable isotope 231; m.p. greater than 1,600℃; b.p. 4,026℃; sp. gr. 15.37 (calcula...