All articles starting with S

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.

Oct 15, 2026

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.

Oct 15, 2026

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.

Oct 22, 2026

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.

Oct 22, 2026

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.

Surfana Vlieland

Surfana Vlieland, also Surfana Beach Hostel Bed & Breakfast, is a surf school and surf camp founded 2011 on Campsite Stortemelk, Kampweg 1, car-free Vlieland, Netherlands, rated 8.6 on Booking.com.

Surfari Surf Shop

Surfari Surf Shop (surfari.ch) is a Zürich surf shop and online retailer at Badenerstrasse 18 near Stauffacher, run by Surfari GmbH and owner Roman Hartmann; over 20 years online, with Surfwise travel agency and an Urbansurf wavepool outlet, distinct from unrelated Surfari shops in Swanage, Gloucester, Florida, and San Diego.