All articles A–Z
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Surface scattering
Surface scattering is the deflection of charge carriers, phonons, or molecules by a material's boundary, becoming dominant in thin films and raising electrical resistivity above the bulk value.
Surface staining
Surface staining labels proteins on the outer membrane of intact cells with fluorophore-conjugated antibodies, the foundation of immunophenotyping, the most common use of flow cytometry.
Surface state
A surface state is an electronic state localized at the surface of a crystal, arising from the abrupt end of the periodic lattice, first predicted by Igor Tamm in 1932.
Surface tension
Surface tension, also called interfacial tension, is a liquid surface's resistance to creating new interface, measurable as force per unit length or energy per area, in newtons per meter.
Surface Transportation Assistance Act of 1982
The Surface Transportation Assistance Act of 1982 is a US federal law signed by Ronald Reagan in 1983 that raised the federal gasoline tax from 4 to 9 cents per gallon.
Surface Transportation Board
The Surface Transportation Board (STB) is an independent US agency that economically regulates freight rail, adjudicating rates and service issues and approving rail mergers since 1996.
Surface under the cumulative ranking curve
The surface under the cumulative ranking curve (SUCRA) scores a treatment's likely ranking in a network meta-analysis from 0 to 1, introduced by Georgia Salanti and colleagues in 2011.
Surface warfare insignia
Surface warfare insignia are U.S. Navy breast pins marking surface warfare qualification: the gold SWO officer pin (1974/1975) and silver Enlisted Surface Warfare Specialist pin (1979), with staff corps variants and 2018 eligibility restrictions.
Surface water
Surface water is water in open bodies on the land surface, such as lakes, rivers, and streams; it is the most visible part of the hydrologic cycle and most cities' source.
Surface wave
A surface wave is a wave whose energy stays concentrated near the boundary between two media, including Rayleigh and Love waves in solids, ocean waves, and surface plasmons.
Surface wave tomography
Surface wave tomography is a seismological imaging method that converts measurements of how seismic surface waves disperse into 3D shear-wave velocity models of the crust and upper mantle.
Surface weather analysis
A surface weather analysis is an analyzed synoptic chart of surface observations, commonly called the weather map, showing sea-level pressure, highs, lows, fronts, and air masses.
Surface X-ray diffraction
Surface X-ray diffraction (SXRD) is an experimental technique that determines the atomic structure of crystal surfaces and buried interfaces, using grazing-incidence synchrotron X-rays and crystal truncation rods.
Surface-area-to-volume ratio
The surface-area-to-volume ratio (SA:V, or S/V) is the quotient of an object's surface area and its volume. It declines as objects grow, limiting cell size and shaping heat transfer and catalysis.
Surface-electrode ion trap
A surface-electrode ion trap is a Paul ion trap with all electrodes in one plane on a chip, holding ions above the surface for scalable quantum computing.
Surface-enhanced infrared absorption spectroscopy
Surface-enhanced infrared absorption spectroscopy (SEIRA, also SEIRAS) is a vibrational spectroscopy technique in which nanostructured gold or silver surfaces amplify infrared absorption of nearby molecules.
Surface-enhanced laser desorption/ionization
Surface-enhanced laser desorption/ionization (SELDI) is a MALDI-style mass spectrometry method that captures proteins from crude biological samples on chemically modified chips, commercialized by Ciphergen in 1997 for protein profiling and biomarker discovery.
Surface-enhanced Raman spectroscopy
Surface-enhanced Raman spectroscopy, also known as surface-enhanced Raman scattering or SERS, amplifies Raman signals from molecules on nanostructured metallic surfaces, enabling detection at very low concentrations.
Surface-enhanced resonance Raman spectroscopy
Surface-enhanced resonance Raman spectroscopy (SERRS) is a Raman technique in which surface enhancement and molecular resonance act together, enabling single-molecule detection, as in a 1995 study of rhodamine 6G.
Surface-guided radiation therapy
Surface-guided radiation therapy (SGRT) uses optical 3D imaging of the patient's body surface for radiotherapy positioning and motion monitoring, without tattoos or added radiation dose.
Surface-initiated polymerization
Surface-initiated polymerization (SIP) is a materials chemistry method that grows polymer chains from initiator-coated solid surfaces, forming dense polymer brush films a few to hundreds of nanometers thick.
Surface-mount technology
Surface-mount technology (SMT) is an electronics assembly method that solders components directly onto the surface of a printed circuit board, now used in about 90% of board assemblies.
Surface-to-air missile
A surface-to-air missile (SAM), also called an antiaircraft missile, is a guided weapon launched from the ground to destroy aircraft and missiles, ranging from short-range defense to systems like the Russian S-400.
Surface-to-surface missile
A surface-to-surface missile, also called a ground-to-ground missile, is a guided missile fired from ground or sea platforms at ground or sea targets, including ballistic and cruise types.
Surfacing
Surfacing is Margaret Atwood's second novel, published in 1972, about an unnamed artist whose search for her missing father in northern Quebec becomes a psychological breakdown.
Surfactant
A surfactant, or surface-active agent, is an amphiphilic compound with a hydrophilic head and hydrophobic tail that lowers water's surface tension and serves as a main detergent ingredient.
Surfactant metabolism
Surfactant metabolism: the synthesis, secretion, extracellular conversion, recycling, and degradation of pulmonary surfactant, a lipoprotein complex made by alveolar type II cells; its disruption causes respiratory distress syndrome and genetic lung disease.
Surfactant therapy
Surfactant therapy is the administration of exogenous pulmonary surfactant into the lungs, principally of premature newborns, to treat respiratory distress syndrome, reducing mortality most in infants under 30 weeks' gestation.
Surfactant-free synthesis
Surfactant-free synthesis is a materials chemistry method for making nanoparticles without surfactant stabilizers, leaving surfaces unblocked; stable precious-metal particles of 2–20 nm are well established.
Surfactin
Surfactin: cyclic lipopeptide biosurfactant from Bacillus subtilis (discovered 1968, Arima et al.), heptapeptide lactone ring plus β-hydroxy fatty acid, lowers water surface tension to 27 mN/m at 20 µM; NRPS-synthesized, low-yield fermentation limits commercial use.