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polonium

(Encyclopedia)polonium pəlōˈnēəm [key], radioactive chemical element; symbol Po; at. no. 84; mass no. of most stable isotope 209; m.p. 254℃; b.p. 962℃; sp. gr. about 9.4; valence +2 or +4. Polonium is an e...

prize

(Encyclopedia)prize, in maritime law, the private property of an enemy that a belligerent captures at sea. For the capture of the vessel or cargo to be lawful it must be made outside neutral waters and by authority...

radioactive isotope

(Encyclopedia)radioactive isotope or radioisotope, natural or artificially created isotope of a chemical element having an unstable nucleus that decays, emitting alpha, beta, or gamma rays until stability is reache...

capillarity

(Encyclopedia)CE5 Capillarity: Water wets the walls of a capillary tube and thus rises, causing the upper surface, or meniscus, of the liquid to be concave; mercury does not wet the walls of a capillary tube and...

nitrogen cycle

(Encyclopedia)CE5 Nitrogen cycle nitrogen cycle, the continuous flow of nitrogen through the biosphere by the processes of nitrogen fixation, ammonification (decay), nitrification, and denitrification. Nitrogen...

suicide

(Encyclopedia)suicide [Lat.,=self-killing], the deliberate taking of one's own life. Suicide may be compulsory, prescribed by custom or enjoined by the authorities, usually as an alternative to death at the hands o...

calculator

(Encyclopedia)calculator or calculating machine, device for performing numerical computations; it may be mechanical, electromechanical, or electronic. The electronic computer is also a calculator but performs other...

Ruwenzori

(Encyclopedia)Ruwenzori ro͞oˌwənzōˈrē [key], mountain range, E central Africa, on the Uganda-Congo border, in the western arm of the Great Rift Valley between lakes Albert and Edward. This fault-block range i...

Rio Treaty

(Encyclopedia)Rio Treaty (Inter-American Treaty of Reciprocal Assistance), signed Sept. 2, 1947, and originally ratified by all 21 American republics. Under the treaty, an armed attack or threat of aggression again...

Seely, John Edward Bernard, 1st baron of Mottistone

(Encyclopedia)Seely, John Edward Bernard, 1st baron of Mottistone, 1868–1947, British politician. He served in the South African War and entered Parliament as a Conservative in 1900. Having switched to the Libera...