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particle accelerator

(Encyclopedia)CE5 Linear accelerator (LINAC) CE5 Cyclotron: As the charged particles move faster, they spiral out to the edge of the Ds. particle accelerator, apparatus used in nuclear physics to produce bea...

space station

(Encyclopedia)space station or space platform, artificial earth satellite, usually manned, that is placed in a fixed orbit and can serve as a base for astronomical observations; zero-gravity materials processing; s...

quantum chromodynamics

(Encyclopedia)quantum chromodynamics (QCD), quantum field theory that describes the properties of the strong interactions between quarks and between protons and neutrons in the framework of quantum theory. Quarks p...

Elementary Particles (table)

(Encyclopedia)Elementary Particles Leptons Quarks1 Gauge Bosons Some Sample Hadrons For each of these particles, except the photon, gluon, and Z-boson, there is an antiparticle with the same mass and op...

meson

(Encyclopedia)meson mēˈzŏn [key] [Gr.,=middle (i.e., middleweight)], class of elementary particles whose masses are generally between those of the lepton class of lighter particles and those of the baryon class ...

magnetic resonance

(Encyclopedia)magnetic resonance, in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then a...

atom

(Encyclopedia)CE5 Bohr-Rutherford atom CE5 Probability distribution of the electron in the hydrogen atom: A. Ground state B. Highly excited state atom [Gr.,=uncuttable (indivisible)], basic unit of matte...

electron

(Encyclopedia)electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the ...

interstellar matter

(Encyclopedia)interstellar matter, matter in a galaxy between the stars, known also as the interstellar medium. The interstellar gas, which constitutes about 99% of the interstellar matter, consists mostly of hyd...

coenzyme

(Encyclopedia)coenzyme kō-ĕnˈzīm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

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