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Atomic Energy Commission

(Encyclopedia)Atomic Energy Commission (AEC), former U.S. government commission created by the Atomic Energy Act of 1946 and charged with the development and control of the U.S. atomic energy program following Worl...

atomic mass unit

(Encyclopedia)atomic mass unit or amu, in chemistry and physics, unit defined as exactly 1⁄12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is e...

law of simple multiple proportions

(Encyclopedia)law of simple multiple proportions, in chemistry, the statement that when two or more elements form more than one compound, the ratio of the weights of one element that combine with a given weight of ...

Atomic Energy Agency, International

(Encyclopedia)Atomic Energy Agency, International (IAEA), independent intergovernmental organization established in 1957 under the aegis of the United Nations to promote safe, secure, and peaceful uses of atomic e...

atomic force microscope

(Encyclopedia)atomic force microscope (AFM), device that uses a spring-mounted probe to image individual atoms on the surface of a material, first developed by Gerd Binnig in 1986. Unlike the scanning tunneling mic...

mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

European Atomic Energy Community

(Encyclopedia)European Atomic Energy Community (Euratom or EAEC), economic organization that came into being as the 3d treaty organization of what has become the European Union; established by the Treaty of Rome (1...

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