fusion

(noun)

A nuclear reaction in which nuclei combine to form more massive nuclei with the concomitant release of energy and often neutrons.

Related Terms

Examples of fusion in the following topics:

  • Fusion Reactors

    • A fusion reactor is designed to use the thermal energy from nuclear fusion to produce electricity.
    • Fusion power is the power generated by nuclear fusion processes.
    • To harness fusion power, a fusion reactor must be built to turn the energy released by fusion into electricity.
    • It was first derived for fusion reactors by John D.
    • State the Lawson criterion for a fusion reactor to be viable

  • The Hydrogen Bomb

    • The hydrogen bomb is a nuclear weapon that uses a mixture of fission and fusion to produce a massive explosion.
    • A thermonuclear weapon is a nuclear weapon designed to use the heat generated by a fission bomb to compress a nuclear fusion stage.
    • This type of weapon is referred to as a hydrogen bomb, or H-bomb, because it employs hydrogen fusion.
    • Oddly, in most applications, the majority of its destructive energy comes from uranium fission, not hydrogen fusion alone.
    • Radiation from a primary fission bomb compresses a secondary section containing both fission and fusion fuel.

  • Nuclear Fusion

    • Fusion is the process that powers active stars, releasing large quantities of energy.
    • Therefore, energy is no longer released when such nuclei are made by fusion; instead, energy is absorbed.
    • The fusion of lighter elements in stars releases energy, as well as the mass that always accompanies it.
    • A substantial energy barrier of electrostatic forces must be overcome before fusion can occur.
    • Therefore, the main technical difficulty for fusion is getting the nuclei close enough to fuse.

  • Steroids

    • The R group at the A:B ring fusion is most commonly methyl or hydrogen, that at the C:D fusion is usually methyl.
    • Decalin, short for decahydronaphthalene, exists as cis and trans isomers at the ring fusion carbon atoms.
    • In the conformational drawings the ring fusion and the angular hydrogens are black.
    • In each of these all chair conformations the rings are fused by one axial and one equatorial bond, and the overall structure is bent at the ring fusion.
    • The fusion of ring C to ring B in a trans configuration prevents ring B from undergoing a conformational flip to another chair form.

  • Heating Curve for Water

    • Instead, use the heat of fusion ($\Delta H_{fusion}$ ) to calculate how much heat was involved in that process: $q=m\cdot \Delta H_{fusion}$, where m is the mass of the sample of water.

  • Borates: Boron-Oxygen Compounds

    • Boron trioxide is produced by treating borax with sulfuric acid in a fusion furnace.

  • Solid to Gas Phase Transition

    • The enthalpy of sublimation (also called heat of sublimation) can be calculated as the sum of the enthalpy of fusion and the enthalpy of vaporization.

  • Nuclear Binding Energy and Mass Defect

    • Nuclear binding energy is also used to determine whether fission or fusion will be a favorable process.
    • For elements lighter than iron-56, fusion will release energy because the nuclear binding energy increases with increasing mass.

  • Iron

    • Iron's very common presence in rocky planets like Earth is due to its abundant production as a result of fusion in high-mass stars.
    • This is where the production of nickel-56 (which decays to the most common isotope of iron) is the last nuclear fusion reaction that is exothermic.

  • Elemental Boron

    • Boron is produced entirely by cosmic ray spallation (as a result of nuclear reactions), and not by stellar nucleosynthesis (not within stars as a result of fusion or supernovae).