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electroweak theory

(Encyclopedia)electroweak theory, a unified field theory that describes two of the fundamental forces in nature, electromagnetism (see electromagnetic radiation) and the weak interaction. The electroweak theory der...

chromosome

(Encyclopedia)chromosome krōˈməsōmˌ [key], structural carrier of hereditary characteristics, found in the nucleus of every cell and so named for its readiness to absorb dyes. The term chromosome is usually res...

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...

ultrasonics

(Encyclopedia)ultrasonics, study and application of the energy of sound waves vibrating at frequencies greater than 20,000 cycles per second, i.e., beyond the range of human hearing. The application of sound energy...

nitric acid

(Encyclopedia)nitric acid, chemical compound, HNO3, colorless, highly corrosive, poisonous liquid that gives off choking red or yellow fumes in moist air. It is miscible with water in all proportions. It forms an a...

Oe, Kenzaburo

(Encyclopedia)Oe, Kenzaburo kĕnˌzäbo͝orˈō ōˈā [key], 1935–2023, Japanese writer, b. Ose,...

xenon

(Encyclopedia)xenon zēˈnŏn [key] [Gr.,=strange], gaseous chemical element; symbol Xe; at. no. 54; at. wt. 131.293; m.p. −111.9℃; b.p. −107.1℃; density 5.86 grams per liter at STP; valence usually 0. Xeno...

baryon

(Encyclopedia)baryon bârˈēŏnˌ [key] [Gr.,=heavy], class of elementary particles that includes the proton, the neutron, and a large number of unstable, heavier particles, known as hyperons. From a technical poi...

tennessine

(Encyclopedia)tennessine tĕnˈəsēn [key], artificially produced radioactive chemical element; symbol Ts; at. no. 117; mass number of most stable isotope 294; m.p., b.p., sp. gr., and valence unknown. Tennessine ...

californium

(Encyclopedia)californium kălˈĭfôrˌnēəm [key] [from California], artificially produced, radioactive metallic chemical element; symbol Cf; at. no. 98; mass no. of most stable isotope 251; m.p. about 900℃; b...

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