All articles starting with N
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Nuclear fission
Nuclear fission, also called atomic fission, is the splitting of an atom's nucleus into smaller nuclei, releasing energy. Discovered in 1938, it sustains chain reactions and powers nuclear power plants.
Nuclear fission product
Nuclear fission products, or fission products, are the highly radioactive nuclei, mainly lighter elements like cesium-137 and strontium-90, formed when heavy elements split in nuclear fission, along with their decay daughters.
Nuclear football
The nuclear football, officially the Presidential Emergency Satchel, is a briefcase of nuclear war plans carried by a military aide so the US president can authorize a strike anywhere.
Nuclear force
The nuclear force, also known as the residual strong interaction or nucleon-nucleon interaction, binds protons and neutrons into atomic nuclei; it is attractive at intermediate distances with a repulsive core below about 0.5 femtometers.
Nuclear Free and Independent Pacific movement
The Nuclear Free and Independent Pacific movement, formed in Fiji in 1975, was a coalition of Indigenous, church, union, and peace activists opposing nuclear testing and colonialism.
Nuclear fuel
Nuclear fuel, also called atomic fuel, is the material that sustains a controlled fission chain reaction in a nuclear reactor, usually ceramic pellets of enriched uranium dioxide in metal tubes.
Nuclear fuel fabrication
Nuclear fuel fabrication is the final front-end step of the nuclear fuel cycle: enriched uranium is made into uranium dioxide pellets, sealed in fuel rods, and assembled for reactor cores.
Nuclear Fuel Services
Nuclear Fuel Services (NFS) is a nuclear fuel fabrication company in Erwin, Tennessee, owned by BWX Technologies, supplying fuel for all U.S. naval reactors since 1957.
Nuclear fusion
Nuclear fusion, or thermonuclear fusion, is a reaction where two light nuclei merge into a heavier one and release energy; it powers the Sun and stars.
Nuclear fusion reactions of fusion fuels
Nuclear fusion reactions of fusion fuels surveys the D–T, D–D, D–³He, and p–¹¹B reactions, their cross sections, energy yields, and ignition conditions, with D–T the easiest to ignite.
Nuclear Gandhi
Nuclear Gandhi, aka Atomic Gandhi, is the urban legend that an integer underflow bug in Civilization (1991) made pacifist Mahatma Gandhi nuke-happy. Sid Meier's 2020 memoir debunked it; later Civ games adopted the joke as canon.
Nuclear graphite
Nuclear graphite is high-purity synthetic graphite used in nuclear reactors as a neutron moderator and often reflector, slowing fast neutrons to thermal energies that sustain the fission chain reaction.
Nuclear gravity bomb
A nuclear gravity bomb is a nuclear weapon dropped from an aircraft and falling under gravity without propulsion, in US service as the B61 family since 1968.
Nuclear holocaust
A nuclear holocaust is the destruction of human civilization by large-scale nuclear war. It has never occurred; Hiroshima and Nagasaki in 1945 remain the only wartime use.
Nuclear hormone receptor, ligand-binding domain
Nuclear hormone receptor ligand-binding domain (LBD), region E of nuclear receptors; C-terminal ~250-residue 12-helix sandwich with hydrophobic ligand-binding pocket and AF-2 helix 12 charge clamp for coactivator recruitment; main drug discovery target.
Nuclear Hydrogen Initiative
The Nuclear Hydrogen Initiative (NHI) was a Department of Energy research program established in 2003 to develop large-scale hydrogen production from nuclear energy; it was terminated at the end of fiscal year 2009.
Nuclear incompressibility
Nuclear incompressibility is the resistance of nuclear matter to compression, measured by the coefficient K∞, about 240 MeV, a key parameter of the nuclear equation of state.
Nuclear Industry Association
The Nuclear Industry Association, formerly the British Nuclear Industry Forum, is the UK's civil nuclear trade association, representing over 340 member companies and campaigning for nuclear power.
Nuclear Installations Inspectorate
The Nuclear Installations Inspectorate (NII) was the United Kingdom's regulator for licensing and inspecting nuclear installations from 1960 until 2011, when its functions passed to the Office for Nuclear Regulation.
Nuclear isomer
A nuclear isomer, or metastable isomer, is an excited nuclear state persisting far longer than the usual microsecond, decaying by gamma emission; technetium-99m enables most nuclear medicine imaging.
Nuclear lattice effective field theory
Nuclear lattice effective field theory (NLEFT) is a computational method in nuclear physics that places nucleons on a spacetime lattice and uses Monte Carlo simulation to predict nuclear properties.
Nuclear level density
The nuclear level density is the number of excited quantum states of an atomic nucleus per unit excitation energy, first calculated by Hans Bethe in 1936.
Nuclear localization sequence
Nuclear localization sequence (NLS): short basic amino acid motif, e.g. SV40 large T PKKKRKV, that directs proteins into the nucleus via importin-mediated nuclear pore transport; classical monopartite and bipartite types plus PY-NLS exist.
Nuclear magic numbers
Nuclear magic numbers are the proton or neutron counts 2, 8, 20, 28, 50, 82, and 126 at which nuclei are unusually stable because a shell of nucleons is completely filled.
Nuclear magnetic moment
The nuclear magnetic moment is the magnetic dipole moment of an atomic nucleus, arising from the spin and orbital moments of its protons and neutrons and measured by magnetic resonance.
Nuclear magnetic resonance
Nuclear magnetic resonance is a phenomenon and measurement technique in which nuclei in a magnetic field absorb radiation at a specific frequency, used for molecular structure determination and medical imaging.
Nuclear magnetic resonance diffusometry
Nuclear magnetic resonance diffusometry is a non-invasive technique, usually using pulsed magnetic field gradients, that measures molecular self-diffusion coefficients in liquids, polymers, and porous materials.
Nuclear magnetic resonance logging
Nuclear magnetic resonance logging is a well-logging technique that measures hydrogen in rock pore space to determine fluids, porosity, and permeability, with tools lowered into the borehole.
Nuclear magnetic resonance of organoselenium and organotellurium compounds
Nuclear magnetic resonance of organoselenium and organotellurium compounds measures ⁷⁷Se and ¹²⁵Te spectra of carbon-bound species to assign structure and stereochemistry, with ¹²⁵Te shifts spanning about 5000 ppm.
Nuclear magnetic resonance of proteins
Nuclear magnetic resonance of proteins is a spectroscopic method that determines protein structures and dynamics in solution at atomic resolution by measuring the magnetic response of hydrogen, carbon, and nitrogen nuclei.