a transuranic element, one of the products of high-energy helium bombardment of uranium and plutonium. Symbol: Am; atomic number: 95.
a white metallic transuranic element artificially produced from plutonium. It is used as an alpha-particle source. Symbol: Am; atomic no: 95; half-life of most stable isotope, 243Am: 7.4 × 10³ years; valency: 2,3,4,5, or 6; relative density: 13.67; melting pt: 1176°C; boiling pt: 2607°C (est)
americium am·er·i·ci·um (ām’ə-rĭsh’ē-əm)
A white metallic synthetic element of the actinide series; its longest-lived isotopes, Am 241 and Am 243, are used as radiation sources in research. Atomic number 95; specific gravity 13.7; valence 2, 3, 4, 5, 6.
Symbol Am A synthetic, silvery-white, radioactive metallic element of the actinide series that is produced artificially by bombarding plutonium with neutrons. Americium is used as a source of alpha particles for smoke detectors and gamma rays for industrial gauges. Its most stable isotope has a half-life of 7,950 years. Atomic number 95; specific gravity 11.7; valence 3, 4, 5, 6. See Periodic Table.
- Americus vespucius
Amerigo [uh-mer-i-goh;; Italian ah-me-ree-gaw] /əˈmɛr ɪˌgoʊ;; Italian ˌɑ mɛˈri gɔ/ (Show IPA), (Americus Vespucius) 1451–1512, Italian merchant, adventurer, and explorer after whom America was named. Historical Examples A few of them had seen the vessels of americus vespucius and Cabral. Martin Rattler R.M. Ballantyne Do you think that americus vespucius deserved so great an honor? […]
a city in SW central Georgia. Historical Examples In one of these letters Americus seems to have written boastfully of how he had found lands which might be called a new world. Introductory American History Henry Eldridge Bourne This seems the more strange since we know so little about the life of Americus. Introductory American […]
- Amerigo vespucci
. Amerigo [uh-mer-i-goh;; Italian ah-me-ree-gaw] /əˈmɛr ɪˌgoʊ;; Italian ˌɑ mɛˈri gɔ/ (Show IPA), (Americus Vespucius) 1451–1512, Italian merchant, adventurer, and explorer after whom America was named. Historical Examples The claims of Amerigo Vespucci to a previous discovery are doubtful. Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 2 Various The pilot of this expedition was an […]
(def 1). of or relating to Amerindians. Historical Examples This young Amerindian was dressed in beaver garments which were a nest of vermin. Pioneers in Canada Sir Harry Johnston He brought the great Amerindian nation of the Dakotas into direct relations with the French. Pioneers in Canada Sir Harry Johnston The only domestic animal possessed […]