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vortex

(Encyclopedia)vortex vôrˈtĕks [key], mass of fluid in whirling or rotary motion. To simplify the analysis, vortex motion usually describes motions in a frictionless fluid. In such cases the absence of friction w...

Zeeman effect

(Encyclopedia)Zeeman effect, splitting of a single spectral line (see spectrum) into a group of closely spaced lines when the substance producing the single line is subjected to a uniform magnetic field. The effect...

benzene

(Encyclopedia)benzene bĕnˈzēn, bĕnzēnˈ [key], colorless, flammable, toxic liquid with a pleasant aromatic odor. It boils at 80.1℃ and solidifies at 5.5℃. Benzene is a hydrocarbon, with formula C6H6. The s...

elementary particles

(Encyclopedia)CE5 elementary particles, the most basic physical constituents of the universe. The first subatomic particle to be discovered was the electron, identified in 1897 by J. J. Thomson. After the...

alkyne

(Encyclopedia)CE5 Alkynes alkyne ălˈkīn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). Alkynes with one triple bond have t...

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...

amino acid

(Encyclopedia)CE5 General formula of an amino acid CE5 Peptide bond between two molecules of the amino acid alanine amino acid əmēˈnō [key], any one of a class of simple organic compounds containin...

chemical reaction

(Encyclopedia)chemical reaction, process by which one or more substances may be transformed into one or more new substances. Energy is released or is absorbed, but no loss in total molecular weight occurs. When, fo...

Potsdam Conference

(Encyclopedia)Potsdam Conference, meeting (July 17–Aug. 2, 1945) of the principal Allies in World War II (the United States, the USSR, and Great Britain) to clarify and implement agreements previously reached at ...

chemical equation

(Encyclopedia)chemical equation, group of symbols representing a chemical reaction. There are a number of other symbols used in chemical equations. A symbol written above or below the reaction arrow indicates spe...