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Sverdrup, Harald Ulrik

(Encyclopedia)Sverdrup, Harald Ulrik häˈräl o͞olˈrĭk svĕrˈdro͝op [key], 1888–1957, Norwegian oceanographer and meteorologist. He was in charge of the scientific work on the Maud for Amundsen's arctic exp...

radiochemistry

(Encyclopedia)radiochemistry, chemistry of radioactive substances (see radioactivity). Radioactive isotopes are very useful as tracers to study the mechanisms of complex organic reactions, since even minute amounts...

Sharpless, Karl Barry

(Encyclopedia)Sharpless, Karl Barry, 1941–, American chemist, b. Philadelphia, Ph.D. Stanford, 1968. Sharpless was a professor at the Massachusetts Institute of Technology (1970–77 and 1980–90) and at Stanfor...

germanium

(Encyclopedia)germanium jərmāˈnēəm [key] [from Germany], semimetallic chemical element; symbol Ge; at. no. 32; at. wt. 72.63; m.p. 937.4℃; b.p. 2,830℃; sp. gr. 5.323 at 25℃; valence +2 or +4. Pure german...

argon

(Encyclopedia)argon ärˈgŏn [key] [Gr.,=inert], gaseous chemical element; symbol Ar; at. no. 18; at. wt. 39.948; m.p. −189.2℃; b.p. −185.7℃; density 1.784 grams per liter at STP; valence 0. Argon is a col...

lanthanum

(Encyclopedia)lanthanum lănˈthənəm [key] [Gr.,=to lie hidden], metallic chemical element; symbol La; at. no. 57; at. wt. 138.90547; m.p. about 920℃; b.p. about 3,460℃; sp. gr. 6.19 at 25℃; valence +3. Lan...

rubidium

(Encyclopedia)rubidium ro͞obĭdˈēəm [key], metallic chemical element; symbol Rb; at. no. 37; at. wt. 85.4678; m.p. 38.89℃; b.p. 686℃; sp. gr. 1.53 at 20℃; valence +1. Rubidium is a very soft silver-white ...

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...

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...

Heck, Richard Fred

(Encyclopedia)Heck, Richard Fred, 1931–2015, American chemist, b. Springfield, Mass., Ph.D. Univ. of California, Los Angeles, 1954. Heck was a researcher at the Hercules Corporation in Wilmington, Del., from 1957...