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boron 音标拼音: [b'ɔr,ɑn] n. 硼 硼 boron n 1: a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder [synonym: {boron}, {B}, {atomic number 5}] Boron \Bo"ron\ (b[=o]"r[o^]n), n. [See {Borax}.] (Chem.) A nonmetallic element occurring abundantly in borax. It is reduced with difficulty to the free state, when it can be obtained in several different forms; viz., as a substance of a deep olive color, in a semimetallic form, and in colorless quadratic crystals similar to the diamond in hardness and other properties. It occurs in nature also in boracite, datolite, tourmaline, and some other minerals. Atomic number 5. Atomic weight 10.81. Symbol B. [1913 Webster] boron Symbol: B Atomic number: 5 Atomic weight: 10.811 An element of group 13 of the periodic table. There are two allotropes, amorphous boron is a brown power, but metallic boron is black. The metallic form is hard (9.3 on Mohs' scale) and a bad conductor in room temperatures. It is never found free in nature. Boron-10 is used in nuclear reactor control rods and shields. It was discovered in 1808 by Sir Humphry Davy and by J.L. Gay-Lussac and L.J. Thenard. Boron, CA -- U.S. Census Designated Place in California
Population (2000): 2025 Housing Units (2000): 1103 Land area (2000): 13.848524 sq. miles (35.867512 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 13.848524 sq. miles (35.867512 sq. km) FIPS code: 07568 Located within: California (CA), FIPS 06 Location: 35.015177 N, 117.660799 W ZIP Codes (1990): 93516 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Boron, CA Boron
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