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Ionization degree

The ionization degree is the fraction of a plasma's heavy particles that are ionized, the parameter that separates weakly ionized gas discharges from fully ionized fusion and arc plasmas.

Ionization energy

Ionization energy, formerly called the ionization potential, is the minimum energy needed to eject an electron from a neutral atom or molecule, forming a positive ion.

Ionization front

An ionization front is the sharp boundary between ionized and neutral interstellar gas, driven outward by ultraviolet light from hot stars and bounding H II regions.

Ionization gauge

An ionization gauge measures low gas pressures indirectly via ion current and is the standard instrument for high and ultrahigh vacuum, its two families being hot- and cold-cathode gauges.

Ionization injection is a method for trapping electrons in a plasma wakefield accelerator, where a laser or particle beam ionizes dopant atoms inside the wake; it was first laser-demonstrated in 2010.

Ionization parameter

The ionization parameter is a dimensionless astrophysical quantity describing the balance between ionizing radiation and gas density in a nebula, defined as the ratio of ionizing photon flux to hydrogen density.

Ionized-air glow

Ionized-air glow, also called air fluorescence or nitrogen fluorescence, is ultraviolet and visible light emitted by excited nitrogen molecules in air bombarded by ionizing radiation.

Ionizing photon escape in early galaxies

Ionizing photon escape in early galaxies is the leakage of hydrogen-ionizing ultraviolet photons into the intergalactic medium. Its escape fraction decides whether star-forming galaxies could have driven cosmic reionization.

Ionizing radiation

Ionizing radiation is energy released by atoms as gamma rays, X-rays, or particles such as alpha, beta, and neutrons, energetic enough to remove electrons from atoms.

Ionna

Ionna is an electric vehicle fast-charging network in North America, founded by seven automakers including BMW, General Motors, and Mercedes-Benz, targeting 30,000 charging bays by 2030.

Oct 21, 2026

Ionocyte

Ionocyte: specialized ion-transporting epithelial cell (mitochondria-rich), first seen in fish gills; pulmonary ionocyte (FOXI1+, CFTR-high) discovered 2018 in airways, relevant to cystic fibrosis.

Ionogel

An ionogel is a soft composite in which an ionic liquid is confined in a polymer network, combining liquid-like ionic conductivity with solid form for sensors and batteries.

Ionomer resin

Ionomer resin is a thermoplastic polymer in which metal ions form ionic cross-links between polymer chains, giving toughness, clarity, and strong heat sealing; DuPont's Surlyn, introduced in the mid-1960s, is the best known.

Ionomer-induced poisoning of Pt fuel cell cathodes

Ionomer-induced poisoning of Pt fuel cell cathodes is the loss of oxygen reduction activity in PEM fuel cells when ionomer sulfonate groups adsorb on platinum, blocking catalytic sites.

Ionomycin

Ionomycin (SQ-23377) is a polyether antibiotic produced by the bacterium Streptomyces conglobatus that binds and transports calcium across membranes; it is widely used in cell biology research and in some fertility clinics for artificial oocyte activation.

Ionone

Ionone is a monocyclic terpenoid ketone, C13H20O, occurring as α and β isomers that smell of violets; over 1,000 metric tons are produced yearly for fragrances and flavors.

Ionophore

An ionophore, or ion carrier, is a compound that carries specific ions through cell or organelle membranes. Many are microbial antibiotics, including over 120 polyethers.

Ionosphere

The ionosphere is the ionized part of Earth's upper atmosphere, roughly 80 to 600 km up, reflecting radio waves for shortwave broadcasting and affecting satellite communication and navigation.

Ionospheric Connection Explorer

Ionospheric Connection Explorer, known as ICON, was a NASA satellite launched in 2019 to study how terrestrial weather and space weather combine to drive Earth's ionosphere.

Ionospheric tomography

Ionospheric tomography is an inverse technique, introduced in 1988, that images ionospheric electron density from total electron content measured along radio paths between satellites and ground receivers.

Ionothermal synthesis

Ionothermal synthesis is a method for preparing crystalline inorganic solids, such as aluminophosphates and metal–organic frameworks, in which an ionic liquid serves as both solvent and template.

Oct 20, 2026

Ionotropic glutamate receptor

Ionotropic glutamate receptors (iGluRs) are tetrameric, cation-permeable ligand-gated ion channels mediating fast excitatory neurotransmission. Four classes: AMPA, kainate, NMDA, and GluD, encoded by 18 genes.

IonQ

IonQ is an American quantum computing company in College Park, Maryland, that builds trapped-ion quantum computers and was founded in 2015 by Christopher Monroe and Jungsang Kim.

Iontophoresis

Iontophoresis is a drug delivery method that uses a small electric current to push charged drugs through the skin, and stimulates sweating for the cystic fibrosis sweat test.

Iontronic memristor

An iontronic memristor is a memristive device whose conductance depends on the history of applied voltages through ion movement, emulating biological synapses in soft materials for neuromorphic computing.

Iontronic neuromorphic devices

Iontronic neuromorphic devices are computing components, including artificial synapses and neurons, that use ions rather than electrons to emulate neural processing, named an IUPAC emerging technology in 2024.

Ionuț Iancu

Ionuț Iancu is the shared name of two Romanian kickboxers: Ionuț Alin Iancu "Tănculeț" (born 1998, heavyweight, GLORY) and "The Titan" (born 1990, light heavyweight, DFS). Covers records, GLORY results, and database discrepancies.