(Encyclopedia) electronegativityelectronegativityĭlĕkˌtrōnĕgətĭvˈətē [key], in chemistry, tendency for an atom to attract a pair of electrons that it shares with another atom (see chemical bond). For…
(Encyclopedia) Nilsson, LennartNilsson, Lennartlĕnˈnärt nĭlˈsôn [key], 1922–2017, Swedish photographer who made pioneering microphotographs of embryos and the human body. Nilsson began his career as…
(Encyclopedia) Mitchell, William (Billy Mitchell), 1879–1936, American army officer and pilot, b. Nice, France. He enlisted (1898) in the U.S. army in the Spanish-American War and received a…
(Encyclopedia) weather satellite, artificial satellite used to gather data on a global basis for improvement of weather forecasting. Information includes cloud cover, storm location, temperature, and…
(Encyclopedia) Sverdrup, Harald UlrikSverdrup, Harald Ulrikhäˈräl &oomacr;lˈrĭk svĕrˈdr&oobreve;p [key], 1888–1957, Norwegian oceanographer and meteorologist. He was in charge of the…
(Encyclopedia) cationcationkătˌīˈən [key], atom or group of atoms carrying a positive charge. The charge results because there are more protons than electrons in the cation. Cations can be formed…
(Encyclopedia) organometallic chemistry, the reactions and use of a class of compounds (R-M) that contain a covalent bond between carbon and metal. They are prepared either by direct reaction of the…
(Encyclopedia) Denali National Park and PreserveDenali National Park and Preservedənälˈē [key], in the Alaska Range, S central Alaska; comprising Denali National Park (4,740,912 acres/1,919,398…
(Encyclopedia) Parsis or ParseesParseesboth: pärˈsēz, pärsēzˈ [key], religious community of India, practicing Zoroastrianism. The Parsis (numbering about 75,000) are concentrated in Maharashtra and…
