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hydrogen fluoride
(Encyclopedia)hydrogen fluoride, chemical compound, HF, a colorless, fuming liquid or colorless gas that boils at 19.54℃. It is miscible with water and is soluble in benzene, toluene, and concentrated sulfuric ac...atomic force microscope
(Encyclopedia)atomic force microscope (AFM), device that uses a spring-mounted probe to image individual atoms on the surface of a material, first developed by Gerd Binnig in 1986. Unlike the scanning tunneling mic...San Jose, city, United States
(Encyclopedia)San Jose sănəzāˈ, săn hōzāˈ [key], city (1990 pop. 782,248), seat of Santa Clara co., W central Calif.; founded 1777, inc. 1850. Along with San Francisco and Oakland the city comprises the fou...hafnium
(Encyclopedia)hafnium hăfˈnēəm [key], metallic chemical element; symbol Hf; at. no. 72; at. wt. 178.49; m.p. about 2,227℃; b.p. 4,602℃; sp. gr. 13.31 at 20℃; valence +4. Hafnium is a lustrous, ductile, si...ceramics
(Encyclopedia)ceramics sərămˈĭks [key], materials made of nonmetallic minerals that have been permanently hardened by firing at a high temperature, or objects made of such materials. Most ceramics resist heat a...ruthenium
(Encyclopedia)ruthenium ro͞othēˈnēəm [key], metallic chemical element; symbol Ru; at. no. 44; at. wt. 101.07; m.p. about 2,310℃; b.p. about 3,900℃; sp. gr. 12.41 at 20℃; valence commonly +2, +3, +4, +6, ...quartz
(Encyclopedia)quartz, one of the commonest of all rock-forming minerals and one of the most important constituents of the earth's crust. Chemically, it is silicon dioxide, SiO2. It occurs in crystals of the hexagon...oxide
(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...supernova
(Encyclopedia)supernova, a massive star in the latter stages of stellar evolution that suddenly contracts and then explodes, increasing its energy output as much as a billionfold. Supernovas are the principal distr...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...Browse by Subject
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