42,772 articles
Meitnerium
Meitnerium, formerly called unnilennium, is a synthetic, highly radioactive chemical element with symbol Mt and atomic number 109, first produced in Darmstadt, Germany in 1982.
Mel-frequency cepstral coefficients
Mel-frequency cepstral coefficients (MFCCs) are audio features that approximate human pitch perception and are widely used in speech recognition, introduced by Davis and Mermelstein in 1980.
Mel-frequency cepstrum
The mel-frequency cepstrum (MFC), which produces mel-frequency cepstral coefficients (MFCCs), represents a sound's short-term power spectrum warped onto the mel scale of perceived pitch and long used in speech recognition.
Melamine foam
Melamine foam, commercially known as Basotect, is a lightweight open-cell foam of melamine-formaldehyde resin used for acoustic panels, thermal insulation, and abrasive magic eraser cleaning sponges.
Melamine phosphate
Melamine phosphate is the salt of melamine and phosphoric acid with formula C₃H₉N₆O₄P, used mainly as a halogen-free flame retardant and, on heating, condensed into melamine polyphosphate.
Melamine resin
Melamine resin, also called melamine-formaldehyde resin, is a thermosetting polymer formed by condensing melamine with formaldehyde into a hard, water-resistant network used in laminates, wood adhesives, coatings, and tableware.
Melanie Mitchell
Melanie Mitchell is a complexity scientist and AI researcher at the Santa Fe Institute, known for the Copycat analogy program and her books on complexity and artificial intelligence.
Melanie S. Sanford
Melanie S. Sanford is an American organometallic and inorganic chemist who has spent her career at the University of Michigan, known for palladium-catalyzed C–H functionalization, new fluorination chemistry, and electrolytes for redox-flow batteries.
Melanie Schnell
Melanie Schnell is a German physical chemist at Kiel University and DESY who studies rotational spectroscopy of cold molecules and microwave detection of molecular chirality.
Melanterite
Melanterite is a monoclinic sulfate mineral, ferrous sulfate heptahydrate (FeSO₄·7H₂O), formed mainly by oxidation of pyrite and marcasite in mine workings, and named in 1850 from the Greek for "copperas."
Melatonin
Melatonin, also known as N-acetyl-5-methoxytryptamine, is a hormone produced chiefly by the pineal gland at night that conveys the darkness signal and helps regulate sleep; it was isolated in 1958.
Melba Phillips
Melba Newell Phillips was an American nuclear physicist who co-discovered the Oppenheimer–Phillips process and, fired in 1952 for refusing to testify, became the first female president of the AAPT.
Meldrum's acid
Meldrum's acid (2,2-dimethyl-1,3-dioxane-4,6-dione) is a cyclic malonate derivative prepared from malonic acid and acetone, used in organic synthesis as a highly acidic building block for heterocycles.
Meliadine mine
The Meliadine mine is a gold mine owned by Agnico Eagle in Nunavut, Canada, 25 km north of Rankin Inlet, which began commercial production in May 2019.
Melissa K. Gardner
Melissa K. Gardner is a biophysicist and professor at the University of Minnesota who studies how proteins control the mechanics and dynamics of microtubules during cell division.
Mellin transform
The Mellin transform is an integral transform converting a function on the positive real axis into a function of a complex variable, the multiplicative counterpart of the Fourier transform.
Melnikov method
The Melnikov method is an analytical technique in dynamical systems theory that predicts chaos by measuring the splitting of stable and unstable manifolds under small perturbations.
Melotte 111
Melotte 111, also called the Coma Star Cluster, is a nearby open star cluster in the constellation Coma Berenices, visible to the naked eye and about 280 light-years from the Sun.
Melotte 20
Melotte 20, also known as the Alpha Persei Cluster, is a nearby open star cluster in Perseus centered on Mirfak, containing roughly 100 young, hot stars.
Melt crystallization
Melt crystallization is a solvent-free purification technique in which crystals grown from an impure melt reject impurities into the liquid, achieving purities above 99.99% for organic chemicals.
Melt flow index
The melt flow index, also called the melt flow rate or melt index, measures how readily molten thermoplastic flows, reported in grams per 10 minutes.
Melt pond
A melt pond is a pool of meltwater that collects on the surface of sea ice, most commonly on Arctic sea ice during summer, where ponds lower albedo and speed melting.
Melt-quenched MOF glasses
Melt-quenched MOF glasses are amorphous hybrid solids made by melting a crystalline metal–organic framework and rapidly cooling it, forming a rare fourth class of glass alongside metallic, inorganic, and organic glasses.
Melting
Melting is the phase transition in which a solid loses its ordered structure and becomes a liquid, normally as temperature rises at a given pressure, and remains one of the less settled problems in condensed-matter physics.
Melting point
The melting point is the temperature at which a substance changes from solid to liquid; the solid and liquid coexist in equilibrium there, and it ideally equals the freezing point.
Melting point depression
Melting point depression is the lowering of a substance's melting temperature by a dissolved solute or by small particle size, described by colligative and Gibbs–Thomson relations.
Melville Wolfrom
Melville Wolfrom was an American carbohydrate chemist who spent his career at Ohio State University and was elected to the National Academy of Sciences in 1950.
Melvin Hochster
Melvin Hochster is an American mathematician known for his work in commutative algebra, including tight closure theory, at the University of Michigan from 1977 to 2022.
Melvin Kranzberg
Melvin Kranzberg (1917–1995) was an American historian who built the history of technology into an academic field, co-founding SHOT, founding Technology and Culture, and formulating Kranzberg's Laws.
Melvin Lax
Melvin Lax (1922–2002) was an American theoretical physicist, a pioneer in quantum optics, known for the quantum theory of laser fluctuations and the Lax-Onsager regression theorem.