42,772 articles
Drinking bird
The drinking bird, also sold as the dippy bird, is a glass novelty toy that tips to dip its beak in water, powered by evaporation and patented in 1946.
Driss Abouabdillah
Driss Abouabdillah is a number theorist known for the Abouabdillah theorem on maximum antichains of integers under divisibility, and for a geometry monograph published in Rabat in 2001.
Drizzle (astronomy)
Drizzle is an image-combination algorithm that resamples and combines dithered telescope exposures onto a finer pixel grid, developed for undersampled Hubble cameras and now standard in HST and JWST pipelines.
Drools
Drools, also known as JBoss Rules, is an open source rule engine and business rule management system written in Java, begun in 2001 and now part of Apache KIE.
Drop (liquid)
A drop is a small volume of liquid bounded by a free surface and held together by surface tension, from raindrops to drops from a nozzle.
Drop impact
Drop impact is the collision of a liquid drop with a solid or liquid surface, ending in deposition, spreading, rebound, or splashing; it matters in inkjet printing, spray cooling, and coating.
Droperidol
Droperidol is a butyrophenone derivative and potent dopamine D2 receptor antagonist used as an antiemetic and antipsychotic, mainly against postoperative nausea and vomiting and for rapid tranquilization.
Droplet countercurrent chromatography
Droplet countercurrent chromatography (DCCC) is an all-liquid chromatography technique, introduced in 1970, in which mobile-phase droplets pass through a stationary liquid under gravity to separate natural products.
Dropleton
The dropleton is a charge-neutral quasiparticle made of four or more electrons and holes that jostles like a tiny liquid droplet, first observed in 2014 in gallium arsenide quantum wells and lasting about 25 picoseconds.
Dropsonde
A dropsonde is an expendable weather instrument released from aircraft that falls on a parachute, measuring pressure, temperature, humidity, and wind; GPS dropwindsondes have improved tropical cyclone forecasts since 1997.
Drostanolone propionate
Drostanolone propionate, also called dromostanolone propionate and sold as Masteron, Drolban, and Masteril, is an injectable anabolic-androgenic steroid once used to palliate recurrent breast cancer.
Drought
A drought is a prolonged absence or marked deficiency of precipitation, affecting an estimated 55 million people each year and causing about USD 307 billion in annual losses.
Drought in Australia
Drought in Australia, also known as the Big Dry, refers to prolonged periods of abnormally low rainfall affecting agriculture and water supplies across the continent.
Drude model
The Drude model, also called the Drude-Lorentz model, is a classical theory of electrical conduction in metals proposed by Paul Drude in 1900, treating electrons as a gas.
Drude polarizable force field
The Drude polarizable force field is a molecular mechanics force field in which each polarizable atom carries a charged Drude particle on a harmonic spring.
Drummond Matthews
Drummond Matthews (Drummond Hoyle Matthews) was a British marine geophysicist who with Fred Vine proposed in 1963 how magnetic stripes on the ocean floor record spreading.
Dry ashing
Dry ashing is a sample-preparation method in analytical chemistry in which organic material is heated in air, typically in a muffle furnace, until only inorganic ash remains.
Dry basis
The dry basis, or dry matter basis, reports a material's composition, such as coal, feed, or stack gas, with all water excluded so values can be compared.
Dry ice
Dry ice, also sold as Cardice, is the solid form of carbon dioxide, used as a refrigerant because it sublimes directly to gas at −78.5 °C, leaving no liquid residue.
Dry intrusion
A dry intrusion is a stream of cold, very dry air that descends from the upper troposphere behind a cyclone's cold front, producing the cloud-free dry slot.
Dry lubricant
A dry lubricant, or solid lubricant, is a solid material that reduces friction and wear without oil or grease, using materials like graphite, molybdenum disulfide, and PTFE.
Dry water
Dry water, also called empty water, is a powder in which water droplets coated in hydrophobic silica release liquid under stress, studied for gas storage and carbon capture.
Drying oil
A drying oil is an oil, usually a vegetable oil, that hardens into a solid film when exposed to air, used since the fifteenth century as the medium of oil paints.
Dryline
A dryline is a boundary separating moist Gulf of Mexico air from dry desert air, typically running north to south across the Great Plains in spring.
DSatur
DSatur (DSATUR, for degree of saturation) is a greedy heuristic for graph coloring proposed by Daniel Brélaz in 1979, provably optimal on bipartite, cycle, wheel, and chordal graphs.
DSHARP
DSHARP, the Disk Substructures at High Angular Resolution Project, was a large ALMA survey led by Sean Andrews that imaged 20 nearby protoplanetary disks at high resolution.
DSV Alvin
DSV Alvin, also known as RV Alvin, is a U.S. Navy-owned research submersible operated by Woods Hole Oceanographic Institution since 1964, reaching depths of 6,500 meters.
DSV Limiting Factor
The DSV Limiting Factor is a two-person submersible rated to 11,000 m, built for Victor Vescovo's Five Deeps Expedition and sold in 2022 to Gabe Newell's Inkfish.
Du Val singularity
A Du Val singularity, also called a rational double point or Kleinian singularity, is a surface singularity classified by the Dynkin diagrams A, D, and E, named after Patrick Du Val.
Dual basis
A dual basis is a basis of the dual space V matched to a basis of V: each functional gives 1 on one basis vector and 0 on the others.