Physical world and mathematics

Melvin Schwartz

Melvin Schwartz (1932–2006) was an American experimental particle physicist who co-discovered the muon neutrino in the 1962 Brookhaven experiment, sharing the 1988 Nobel Prize in Physics.

Melvin Spencer Newman

Melvin Spencer Newman (1908–1993) was an American organic chemist at Ohio State University known for the Newman projection, a notation for viewing molecules down carbon–carbon bonds.

Melvin E. Stern (1929–2010) was an American physical oceanographer, a founding father of geophysical fluid dynamics, known for discovering salt fingers and for the monograph Ocean Circulation Physics.

Melvyn J. Shochet

Melvyn J. Shochet is an American experimental particle physicist at the University of Chicago who led the CDF collaboration to the 1995 discovery of the top quark.

Member checking

Member checking, also called participant or respondent validation, is a qualitative research technique in which data and interpretations are returned to participants to check for accuracy.

Membership and federation affiliation of physics societies

Physics societies count members differently: individual societies like the American Physical Society, with over 50,000 scientists, enroll people, while IUPAP's 52 territorial members are national communities adhering through academies.

Membership services and professional development in physics teacher associations

Membership services and professional development in physics teacher associations are the benefits societies like the AAPT and Institute of Physics offer teachers, including journals, conferences, workshops, and mentoring networks.

Membrane extraction

Membrane extraction is a sample preparation technique in analytical chemistry in which a selective membrane extracts and concentrates analytes from liquid or gas samples before analysis.

Membrane extraction with a sorbent interface

Membrane extraction with a sorbent interface (MESI) is a solvent-free sample preparation technique that extracts volatile organic compounds across a polymer membrane for gas chromatographic trace analysis.

Membrane filter

A membrane filter is a thin, porous polymeric or ceramic sheet with controlled pore size that removes particles and bacteria from fluids; sterilizing grades are rated 0.2 µm.

Membrane fluidity

Membrane fluidity describes how easily lipid and protein molecules move within a biological membrane's bilayer, determined by temperature and lipid composition such as unsaturated fatty acids and cholesterol.

Membrane paradigm

The membrane paradigm is an approach to black-hole physics in which the event horizon is replaced by a stretched horizon behaving like a viscous, electrically conducting fluid.

Membrane physics

Membrane physics is the field describing lipid bilayers and vesicles with continuum theory, chiefly the Helfrich curvature energy, measuring elastic constants by micromanipulation and simulation.

Membrane polarization

Membrane polarization is a mechanism of induced polarization in rocks and soils, in which clay surfaces and narrow pores form ion-selective zones that build up charge-storing ion concentration gradients.

Membrane protein

A membrane protein is a protein associated with a cell or organelle membrane, either embedded in the lipid bilayer or bound to its surface; over 40% of drug targets are membrane proteins.

Membrane reactor

A membrane reactor is a chemical or biochemical reactor combining reaction and membrane separation in one device, an example of process intensification best developed for hydrogen production.

Membrane separation

Membrane separation is a family of methods that split fluid mixtures with selectively permeable barriers, driven by pressure, concentration, or electrical potential, including reverse osmosis and electrodialysis.

Membrane-inlet mass spectrometry

Membrane-inlet mass spectrometry, also called membrane introduction mass spectrometry, is an analytical technique where volatile compounds diffuse through a semipermeable membrane directly into a mass spectrometer, introduced in 1963.

Memory foam

Memory foam, also called temper foam or visco-elastic foam, is a polyurethane foam that molds to body heat and pressure; it was developed under a NASA contract in 1966.

MEMS atomic clock

A MEMS atomic clock, usually called a chip-scale atomic clock (CSAC), is a tiny, low-power atomic clock built with microelectromechanical systems for battery-powered portable equipment.

MEMS deformable mirror

A MEMS deformable mirror is a reflective optical device, built with microelectromechanical systems fabrication, whose surface is deformed electrostatically to correct wavefront distortions in adaptive optics systems.

MEMS micropump

A MEMS micropump is a microscale pumping device fabricated with microelectromechanical systems technology that moves fluids precisely at low power, typically for drug delivery, lab-on-a-chip analysis, and microelectronic cooling.

Menahem Max Schiffer

Menahem Max Schiffer (1911–1997) was a German-born American mathematician, professor of mathematics at Stanford from 1952 to 1977, known for the variational method in univalent function theory called the Schiffer variation.

Menaion

The Menaion (Greek: Μηναίον, from mēn, "month") is the set of twelve liturgical books of the Byzantine rite containing offices for the feasts fixed to calendar dates.

Mendeleev's predicted elements

Mendeleev's predicted elements, known through Mendeleevian nomenclature, are elements Dmitri Mendeleev inferred from gaps in his 1869 periodic table, including eka-aluminum, found as gallium in 1875.

Mendelevium

Mendelevium (formerly Unnilunium) is a synthetic radioactive actinide with symbol Md and atomic number 101, first synthesized in 1955 at Berkeley and named after Dmitri Mendeleev.

Mendelian randomization

Mendelian randomization, or MR, is a method in genetic epidemiology that uses inherited genetic variants as instrumental variables to test causal effects, reducing confounding in observational studies.

Mendenhall Glacier

Mendenhall Glacier, known in Tlingit as Sitaantaagu, is a 13-mile glacier near Juneau, Alaska, that flows from the Juneau Icefield and has retreated several kilometers since the Little Ice Age.

Mendenhall Order

The Mendenhall Order, an 1893 administrative decision issued by Thomas Corwin Mendenhall of the Coast and Geodetic Survey, defined the US yard and pound as derived from the international prototype meter and kilogram, replacing British standards.