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ethylene

(Encyclopedia)ethylene ĕthˈēn [key], H2C=CH2, a gaseous unsaturated hydrocarbon. It is the simplest alkene. Ethylene is colorless, has a faint odor, and has a slightly sweet taste; it melts at −169.4℃ and bo...

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...

Rosenberg Case

(Encyclopedia)Rosenberg Case, in U.S. history, a lengthy and controversial espionage case. In 1950, the Federal Bureau of Investigation arrested Julius Rosenberg (1918–53), an electrical engineer who had worked (...

Wu, Chien-Shiung

(Encyclopedia)Wu, Chien-Shiung chyĕnˈ-shyo͝ongˈ wo͞o [key], 1912–97, Chinese-American physicist. She emigrated to the United States from China in 1936 and received a Ph.D. from the Univ. of California, Berke...

antiseptic

(Encyclopedia)antiseptic, agent that kills or inhibits the growth of microorganisms on the external surfaces of the body. Antiseptics should generally be distinguished from drugs such as antibiotics that destroy mi...

ether, in chemistry

(Encyclopedia)CE5 Ethers ether, any of a number of organic compounds whose molecules contain two hydrocarbon groups joined by single bonds to an oxygen atom. The most common of these compounds is ethyl ether, C...

phosphoric acid

(Encyclopedia)phosphoric acid, any one of three chemical compounds made up of phosphorus, oxygen, and hydrogen (see acids and bases). The most common, orthophosphoric acid, H3PO4, is usually simply called phosphori...

white lead

(Encyclopedia)white lead, heavy, white substance, poisonous, insoluble in water, extensively used as a white pigment and base in paints. It is one of the oldest paint pigments used by humans. Chemically, it is basi...

diffusion

(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...

exobiology

(Encyclopedia)exobiology or astrobiology, search for extraterrestrial life within the solar system and throughout the universe. Philosophical speculation that there might be other worlds similar to ours dates back ...