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maser

(Encyclopedia)maser māˈzər [key], device for creation, amplification, and transmission of an intense, highly focused beam of high-frequency radio waves. The name maser is an acronym for microwave amplification b...

hydrocarbon

(Encyclopedia)hydrocarbon hīˌdrōkärˈbən [key], any organic compound composed solely of the elements hydrogen and carbon. The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their ...

anemia

(Encyclopedia)anemia ənēˈmēə [key], condition in which the concentration of hemoglobin in the circulating blood is below normal. Such a condition is caused by a deficient number of erythrocytes (red blood cell...

Sanger, Frederick

(Encyclopedia)Sanger, Frederick săngˈər [key], 1918–2013, British biochemist, grad. Cambridge (B.A., 1939; Ph.D., 1943). He continued his research at Cambridge after 1943. He won the 1958 Nobel Prize in Chemis...

cyano group

(Encyclopedia)cyano group sīˈənō, sī-ănˈō [key], in chemistry, functional group that consists of a carbon atom joined to a nitrogen atom by a triple bond; it can be joined to an atom or another group by a s...

Edelman, Gerald Maurice

(Encyclopedia)Edelman, Gerald Maurice, 1929–2014, American biochemist and neuroscientist, b. Queens, N.Y., M.D. Univ. of Pennsylvania, 1954; Ph.D. Rockefeller Institute, 1960. He was a professor at the Rockefelle...

alkyl group

(Encyclopedia)alkyl group ălˈkĭl [key], in chemistry, group of carbon and hydrogen atoms derived from an alkane molecule by removing one hydrogen atom (see radical). The name of the alkyl group is derived from t...

protonation

(Encyclopedia)protonation prōˈtənāˌshən [key], in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a sin...

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...

Betzig, Robert Eric

(Encyclopedia)Betzig, Robert Eric, 1960–, American physicist, b. Ann Arbor, Mich., Ph.D. Cornell, 1988. Betzig worked at AT&T Bell Laboratories from 1988 to 1996, when he become vice president of research and...