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bolometer
(Encyclopedia)bolometer bōlŏmˈətər, bə– [key], instrument for detecting and measuring radiation, e.g., visible light, infrared radiation, and ultraviolet radiation, in amounts as small as one millionth of a...tetraethyl lead
(Encyclopedia)tetraethyl lead tĕtˌrəĕthˈəl [key], (C2H5)4Pb, viscous, colorless, poisonous liquid. It is an organometallic compound prepared by reacting ethyl chloride with a sodium-lead alloy. When added to ...surface chemistry
(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...Pohl, Frederik
(Encyclopedia)Pohl, Frederik (Frederik George Pohl, Jr.) pōl [key], 1919–2013, American science-fiction writer, b. New York City. Early in his career he often collaborated with other writers, particularly Cyril ...ore
(Encyclopedia)ore, metal-bearing mineral mass that can be profitably mined. Nearly all rock deposits contain some metallic minerals, but in many cases the concentration of metal is too low to justify mining the ore...electrode
(Encyclopedia)electrode, terminal through which electric current passes between metallic and nonmetallic parts of an electric circuit. In most familiar circuits current is carried by metallic conductors, but in som...Mpumalanga
(Encyclopedia)Mpumalanga, province (2011 pop. 4,039,939), 29,535 sq mi (76,495 sq km), E South Africa. In 1994, under South Africa's post-apartheid constitution, Mpumalanga was created from the eastern portion of t...Limpopo, province, South Africa
(Encyclopedia)Limpopo, province (2011 pop. 5,404,868), 48,554 sq mi (125,754 sq km), NE South Africa. In 1994, under South Africa's post-apartheid constitution, Limpopo was created from the northern portion of the ...bead test
(Encyclopedia)bead test, test used in the identification of certain metals. Some metallic ions that cannot be identified by a flame test are identified by a bead test. The test can also be used to confirm the resul...metal
(Encyclopedia)metal, chemical element displaying certain properties by which it is normally distinguished from a nonmetal, notably its metallic luster, the capacity to lose electrons and form a positive ion, and th...Browse by Subject
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