42,772 articles
Justin J. Hagerty
Justin J. Hagerty is an American geoscientist specializing in lunar geochemistry and remote sensing who directed the USGS Astrogeology Science Center in Flagstaff, Arizona, from 2018 to 2024.
Justin Sheffield
Justin Sheffield is a British-based hydrologist, Professor and Head of the School of Geography and Environmental Science at the University of Southampton, known for global drought monitoring and analysis.
Justin Stevens
Justin Stevens is an American nuclear physicist at William & Mary who won the 2019 Presidential Early Career Award and leads GlueX detector work at Jefferson Lab.
Justus von Liebig
Justus von Liebig (1803–1873) was a German chemist who founded agricultural chemistry and created the first laboratory-based system for training research chemists at the University of Giessen.
Jüttner distribution
The Jüttner distribution, also called the Maxwell–Jüttner or relativistic Maxwellian, is the equilibrium distribution of a relativistic gas, derived by Ferencz Jüttner in 1911 as the relativistic generalization of the Maxwell–Boltzmann distribution.
Juyoung Yoon
Juyoung Yoon (born 1964) is a South Korean chemist at Ewha Womans University known for fluorescent probes and activatable photosensitizers for cancer imaging and therapy.
JWH-018
JWH-018, also known as AM-678, is a synthetic cannabinoid developed by John W. Huffman at Clemson University in 1995, later found in the smoking mixture Spice.
JWST exoplanet atmosphere spectroscopy
JWST exoplanet atmosphere spectroscopy measures how starlight filtered through an exoplanet's atmosphere changes with infrared wavelength, revealing composition, temperature, and clouds on planets outside the Solar System.
JWST infrared spectroscopy
JWST infrared spectroscopy is the observation of infrared spectra by the James Webb Space Telescope, whose four instruments cover 0.6 to 28 micrometers from Lagrange point 2.
JYFLTRAP
JYFLTRAP is a double Penning trap mass spectrometer at the IGISOL facility of the University of Jyväskylä, Finland, measuring masses of short-lived radioactive ions since 2003.
K-epsilon turbulence model
The k-epsilon (k-ε) model is a two-equation turbulence closure for RANS computational fluid dynamics, formulated by Launder and Spalding in 1974 and widely used in industry.
K-essence
K-essence is a class of dark energy models where a scalar field with non-canonical kinetic terms, not just its potential, drives the universe's late-time accelerated expansion.
K-index (meteorology)
The K-index (KI) is a meteorological measure of an air mass's thunderstorm potential, computed from temperature and dew point at 850, 700, and 500 hPa of a sounding.
k-induction
k-induction is a proof technique that verifies safety properties of transition systems by checking that the property holds in the first k states of every execution.
k-omega model
The k-omega model is a two-equation turbulence model that solves transport equations for turbulence kinetic energy and specific dissipation rate; its best-known variant is Menter's 1994 SST model.
K-shell ionization
K-shell ionization is the removal of an atom's innermost 1s electron by a photon, electron, or ion, leaving a vacancy that relaxes by X-ray or Auger emission.
k-space (MRI)
In magnetic resonance imaging, k-space is the raw data space holding spatial Fourier transform samples of the object; the image is recovered afterward by Fourier reconstruction.
K-stability
K-stability is an algebro-geometric stability condition for Fano varieties, introduced by Gang Tian and reformulated algebraically by Simon Donaldson, that characterizes which Fano manifolds admit Kähler–Einstein metrics.
K-theory
K-theory is a branch of mathematics assigning algebraic invariants, the K-groups, to spaces, rings, and operator algebras; introduced by Grothendieck in 1957, it splits into algebraic and topological branches.
K-type main-sequence star
A K-type main-sequence star, or orange dwarf, is a cool hydrogen-burning star slightly smaller and dimmer than the Sun, a favored target in the search for habitable exoplanets.
K–Ar dating
K–Ar dating, also called potassium–argon dating or K-Ar, is a radiometric dating method that determines the age of volcanic rocks and minerals from the decay of radioactive potassium-40 to argon-40.
K. Alex Müller
K. Alex Müller (Karl Alexander Müller) was a Swiss physicist at IBM Zurich who co-discovered high-temperature superconductivity in 1986 and won the 1987 Nobel Prize.
K. Barry Sharpless
K. Barry Sharpless, born 1941, is an American chemist at Scripps Research who founded click chemistry and won the Nobel Prize in Chemistry in 2001 and 2022.
K. Birgitta Whaley
K. Birgitta Whaley (K. B. Whaley), born 1956, is an American-based theoretical chemical physicist at UC Berkeley, director of its Quantum Information and Computation Center, known for decoherence-free subspaces.
K. Ferdinand Braun
K. Ferdinand Braun (Karl Ferdinand Braun) was a German physicist who invented the cathode-ray tube and shared the 1909 Nobel Prize in Physics with Marconi.
K. O. Emery
K. O. Emery, born Kenneth Orris Emery, was a Canadian-born marine geologist at Woods Hole Oceanographic Institution who reconstructed drowned landscapes and sea-level history of continental shelves.
K. Uno Ingard
K. Uno Ingard, born Karl Uno Ingard (1921–2014), was a Swedish-born physicist and acoustician who spent his career at MIT working in acoustics and plasma physics.
K2-18b
K2-18b is a temperate sub-Neptune exoplanet orbiting the red dwarf K2-18 in Leo, about 120 light-years away, discovered in 2015 and known for contested signs of life.
K3 surface
A K3 surface, also called a K3 manifold, is a compact complex surface with trivial canonical bundle and vanishing irregularity, making it a two-dimensional Calabi-Yau manifold central to string theory.
Kaali crater
Kaali crater, also known as Kaalijärv crater, is a meteorite impact crater field on Saaremaa Island, Estonia, formed by an iron meteorite in the postglacial period.