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semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

Dauphiné

(Encyclopedia)Dauphiné dōfēnāˈ [key], region and former province, SE France, bordering on Italy. It is now divided into three departments, Haute-Alpes, Isère, and Drôme. In the east the Alps culminate in the...

Corey, Elias James

(Encyclopedia)Corey, Elias James, 1928–, American organic chemist and educator, b. Methuen, Mass., grad. Massachusetts Institute of Technology (B.S. 1948, Ph.D. 1951). He has taught at the Univ. of Illinois (1951...

moscovium

(Encyclopedia)moscovium mŏskōˈvēəm [key], artificially produced radioactive chemical element; symbol Mc; at. no. 115; mass number of most stable isotope 288; m.p., b.p., sp. gr., and valence unknown. Situated ...

Hare, Robert

(Encyclopedia)Hare, Robert, 1781–1858, American chemist, b. Philadelphia. He was professor of chemistry (1819–47) at the medical college of the Univ. of Pennsylvania. Hare made important contributions to early ...

List, Benjamin

(Encyclopedia)List, Benjamin, 1968–, b. Frankfurt, Germany. German chemist, Managing Director of the Max Planck Institute for Coal Research and Professor of organic...

Black, Joseph

(Encyclopedia)Black, Joseph, 1728–99, Scottish chemist and physician, b. France. He was professor of chemistry at Glasgow (1756–66) and from 1766 at Edinburgh. He is best known for his theories of latent heat a...

Ernst, Richard Robert

(Encyclopedia)Ernst, Richard Robert 1933–2021, Swiss chemist, Swiss Federal Institute of Technology Zurich (ETH Zurich; B.S., 1956, Ph.D., 1962). He worked as a res...

Higgins, William

(Encyclopedia)Higgins, William, b. 1762 or 1763, d. 1825, Irish chemist. After study at Oxford he became supervisor of the Royal Dublin Society's mineralogical collection and in 1800 the Society's professor of chem...

tin

(Encyclopedia)tin, metallic chemical element; symbol Sn [Lat. stannum]; at. no. 50; at. wt. 118.710; m.p. 231.9681℃; b.p. 2,270℃; sp. gr. 5.75 (gray), 7.3 (white); valence +2 or +4. Tin exhibits allotropy; abov...