All articles A–Z

Supercritical carbon dioxide

Supercritical carbon dioxide, also known as supercritical CO2, is carbon dioxide held above its critical point of 31.1 °C and 7.38 MPa, used as a tunable solvent and working fluid.

Supercritical carbon dioxide Brayton cycle

The supercritical carbon dioxide Brayton cycle is a closed power cycle that uses carbon dioxide held above its critical point as the working fluid to convert heat into electricity.

Supercritical carbon dioxide cycle

The supercritical carbon dioxide cycle is a closed Brayton power cycle using carbon dioxide above its critical point, enabling compact turbomachinery and higher efficiency than steam plants.

Supercritical carbon dioxide extraction

Supercritical carbon dioxide extraction is a separation process using carbon dioxide above its critical point, 31.06 °C and 73.8 bar, as a tunable solvent, best known for decaffeinating coffee.

Oct 22, 2026

Supercritical CO2 as a C1 building block

Supercritical carbon dioxide is CO2 held above 31 °C and 7.4 MPa, used as a tunable green solvent and as a C1 building block for carbonates, carboxylic acids, and methanol.

Supercritical CO2 Brayton cycle

The supercritical CO2 Brayton cycle is a closed power cycle using carbon dioxide above its critical point as the working fluid instead of steam, pursued for nuclear, fossil, and solar power.

Supercritical Compressed Air Energy Storage

Supercritical compressed air energy storage (SC-CAES) is a form of compressed air energy storage that stores air above its critical pressure, reusing compression heat, avoiding fuel combustion.

Supercritical drying, also known as critical point drying, is a laboratory technique that removes pore liquid without capillary stress, best known for producing aerogels and preparing delicate specimens for electron microscopy.

Supercritical fluid

A supercritical fluid is a substance above its critical temperature and pressure, combining gas-like diffusivity with liquid-like solvating power that can be tuned by adjusting pressure.

Supercritical fluid chromatography

Supercritical fluid chromatography (SFC) is a chromatographic technique using carbon dioxide above its critical point as the mobile phase, offering faster separations than HPLC for nonvolatile compounds.

Supercritical fluid chromatography–mass spectrometry

Supercritical fluid chromatography–mass spectrometry (SFC–MS) is an analytical technique that separates compounds using supercritical carbon dioxide and identifies them by mass spectrometry, widely used in pharmaceutical research and lipidomics.

Supercritical fluid extraction

Supercritical fluid extraction (SFE) is a separation process that uses fluids above their critical point, usually carbon dioxide, to extract compounds for coffee decaffeination, hop extraction, and flavor recovery.

Supercritical fluid extraction–supercritical fluid chromatography

Supercritical fluid extraction–supercritical fluid chromatography (SFE-SFC) is an analytical workflow that extracts analytes with supercritical carbon dioxide, then separates them directly on an SFC column.

Supercritical methanol method

The supercritical methanol method, also called the Saka method, is a catalyst-free process for making biodiesel, introduced in 2001 by Shiro Saka and Dadan Kusdiana at Kyoto University.

Supercritical steam cycle

A supercritical steam cycle is a Rankine power cycle operating above water's critical point of 374 °C and 22.1 MPa, the standard high-efficiency configuration of large coal-fired power plants.

Supercritical water gasification

Supercritical water gasification (SCWG) is a thermochemical process that converts wet biomass and waste into hydrogen-rich gas with water above its critical point, requiring no drying.

Supercritical water gasification of biomass

Supercritical water gasification (SCWG) of biomass is a thermochemical process that gasifies wet biomass in water above its critical point into hydrogen-rich gas, pioneered at MIT in 1978.

Supercritical water oxidation

Supercritical water oxidation is a waste treatment method that destroys organic contaminants in water above its critical point, converting them to carbon dioxide and water.

Supercritical water reactor

The supercritical water reactor (SCWR) is a Generation IV nuclear reactor concept whose water coolant operates above 374 °C and 22.1 MPa, reaching about 45% thermal efficiency.

Supercruise

Supercruise, also called super cruising or supersonic cruising, is sustained supersonic flight on engine thrust alone, without the fuel-hungry afterburner; the F-22 demonstrated it in 1999.

Oct 21, 2026

Supercup

Supercup: a short football competition matching the winners of a region's two main competitions. Covers the UEFA Super Cup (since 1973), CAF Super Cup (1993, Al Ahly record 8 titles), and the Egyptian Super Cup (2001, Al Ahly 16 titles).

Superdeformation

Superdeformation is an extreme, stable elongation of an atomic nucleus into a prolate ellipsoid roughly 2:1 in axis ratio, first seen as fission isomers in the actinides.

Superdelegate

Superdelegates, formally unpledged party leaders and elected officials, are Democratic convention delegates seated by office or party position rather than primaries. Created by the 1982 Hunt Commission, first used in 1984, barred from first-ballot voting in 2018.

Superdense coding

Superdense coding, also known as quantum dense coding, is a quantum communication protocol that transmits two classical bits by sending one qubit, proposed by Bennett and Wiesner in 1992.

Superdeterminism

Superdeterminism: quantum interpretations that explain Bell-test correlations locally and deterministically by rejecting statistical independence between hidden variables and measurement settings. Coined by John Bell; key model is 't Hooft's Cellular Automaton Interpretation; criticized as conspiratorial, defended by Hossenfelder and Palmer.

Superdollar

A superdollar, also called a supernote, is a high-quality counterfeit US $50 or $100 bill, first detected in the Philippines in 1989 and often passing ordinary inspection.

Superdrag

Superdrag is a power pop band from Knoxville, Tennessee, formed in 1992 by John Davis, known for the 1996 hit "Sucked Out" from Regretfully Yours on Elektra, later Arena Rock albums, breakups, and reunions.

Superdry

Superdry is a British premium casualwear brand and retailer founded in 2003 by Julian Dunkerton and James Holder, known for vintage Americana styling with Japanese graphics, floated in 2010, restructured after heavy losses, and now trading as Superdry & Co.

Superelevation

Superelevation, also called banking, is the cross slope built into a roadway on a horizontal curve, supplying part of the lateral acceleration needed to follow it and serving as a controlling design criterion in highway engineering.