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63837 | https://en.wikipedia.org/wiki/Diplura | Diplura | The order Diplura ("two-pronged bristletails") is one of three orders of non-insect hexapods within the class Entognatha (alongside Collembola (springtails) and Protura). The name "diplura", or "two tails", refers to the characteristic pair of caudal appendages or filaments at the terminal end of the body.
Around 800 ... | Biology and health sciences | Non-insect hexapods | Animals |
63844 | https://en.wikipedia.org/wiki/Protura | Protura | The Protura, or proturans, and sometimes nicknamed coneheads, are very small (0.6–1.5mm long), soil-dwelling animals, so inconspicuous they were not noticed until the 20th century. The Protura constitute an order of hexapods that were previously regarded as insects, and sometimes treated as a class in their own right.
... | Biology and health sciences | Non-insect hexapods | Animals |
63847 | https://en.wikipedia.org/wiki/Formaldehyde | Formaldehyde | Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as aqueous solutions (formalin), which consists mainly of the hydrate CH2(OH)2. I... | Physical sciences | Carbon–oxygen bond | null |
63904 | https://en.wikipedia.org/wiki/Match | Match | A match is a tool for starting a fire. Typically, matches are made of small wooden sticks or stiff paper. One end is coated with a material that can be ignited by friction generated by striking the match against a suitable surface. Wooden matches are packaged in matchboxes, and paper matches are partially cut into rows... | Technology | Lighting | null |
63915 | https://en.wikipedia.org/wiki/Static%20random-access%20memory | Static random-access memory | Static random-access memory (static RAM or SRAM) is a type of random-access memory (RAM) that uses latching circuitry (flip-flop) to store each bit. SRAM is volatile memory; data is lost when power is removed.
The static qualifier differentiates SRAM from dynamic random-access memory (DRAM):
SRAM will hold its data p... | Technology | Volatile memory | null |
63973 | https://en.wikipedia.org/wiki/Wi-Fi | Wi-Fi | Wi-Fi () is a family of wireless network protocols based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio waves. These are the most widely used computer networks, used globally in home and ... | Technology | Networks | null |
63978 | https://en.wikipedia.org/wiki/Fresnel%20lens | Fresnel lens | A Fresnel lens ( ; ; or ) is a type of composite compact lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.
The simpler dioptric (purely refractive) form of the lens was first proposed by Georges-Louis Leclerc, Comte de B... | Technology | Optical components | null |
64020 | https://en.wikipedia.org/wiki/Multiprocessing | Multiprocessing | Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There are many variations on this basic theme, and the definition of multiprocessin... | Technology | Computer architecture concepts | null |
64150 | https://en.wikipedia.org/wiki/Sphynx%20cat | Sphynx cat | The Sphynx cat (pronounced , ) also known as the Canadian Sphynx, is a breed of cat known for its lack of fur. Hairlessness in cats is a naturally occurring genetic mutation, and the Sphynx was developed through selective breeding of these animals, starting in the 1960s.
The skin has a texture of chamois leather, as ... | Biology and health sciences | Cats | Animals |
64204 | https://en.wikipedia.org/wiki/Kinetic%20theory%20of%20gases | Kinetic theory of gases | The kinetic theory of gases is a simple classical model of the thermodynamic behavior of gases. Its introduction allowed many principal concepts of thermodynamics to be established. It treats a gas as composed of numerous particles, too small to be seen with a microscope, in constant, random motion. These particles are... | Physical sciences | Thermodynamics | Physics |
64212 | https://en.wikipedia.org/wiki/Potassium%20nitrate | Potassium nitrate | Potassium nitrate is a chemical compound with a sharp, salty, bitter taste and the chemical formula . It is a potassium salt of nitric acid. This salt consists of potassium cations and nitrate anions , and is therefore an alkali metal nitrate. It occurs in nature as a mineral, niter (or nitre outside the US). It is a ... | Physical sciences | Salts | null |
64219 | https://en.wikipedia.org/wiki/Bernoulli%27s%20principle | Bernoulli's principle | Bernoulli's principle is a key concept in fluid dynamics that relates pressure, density, speed and height. Bernoulli's principle states that an increase in the speed of a parcel of fluid occurs simultaneously with a decrease in either the pressure or the height above a datum. The principle is named after the Swiss math... | Physical sciences | Fluid mechanics | null |
64343 | https://en.wikipedia.org/wiki/Moir%C3%A9%20pattern | Moiré pattern | In mathematics, physics, and art, moiré patterns ( , , ) or moiré fringes are large-scale interference patterns that can be produced when a partially opaque ruled pattern with transparent gaps is overlaid on another similar pattern. For the moiré interference pattern to appear, the two patterns must not be completely ... | Physical sciences | Optics | Physics |
64493 | https://en.wikipedia.org/wiki/Percentage | Percentage | In mathematics, a percentage () is a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign (%), although the abbreviations pct., pct, and sometimes pc are also used. A percentage is a dimensionless number (pure number), primarily used for expressing proportions, but percent is nonet... | Mathematics | Basics | null |
64592 | https://en.wikipedia.org/wiki/Hallway | Hallway | A hallway (also passage, passageway, corridor or hall) is an interior space in a building that is used to connect other rooms. Hallways are generally long and narrow.
Hallways must be sufficiently wide to ensure buildings can be evacuated during a fire, and to allow people in wheelchairs to navigate them. The minimum ... | Technology | Architectural elements | null |
64656 | https://en.wikipedia.org/wiki/Hue | Hue | In color theory, hue is one of the main properties (called color appearance parameters) of a color, defined technically in the CIECAM02 model as "the degree to which a stimulus can be described as similar to or different from stimuli that are described as red, orange, yellow, green, blue, violet," within certain theori... | Physical sciences | Basics | Physics |
64669 | https://en.wikipedia.org/wiki/De%20Morgan%27s%20laws | De Morgan's laws | In propositional logic and Boolean algebra, De Morgan's laws, also known as De Morgan's theorem, are a pair of transformation rules that are both valid rules of inference. They are named after Augustus De Morgan, a 19th-century British mathematician. The rules allow the expression of conjunctions and disjunctions purel... | Mathematics | Mathematical logic | null |
64919 | https://en.wikipedia.org/wiki/Environmental%20science | Environmental science | Environmental science is an interdisciplinary academic field that integrates physics, biology, meteorology, mathematics and geography (including ecology, chemistry, plant science, zoology, mineralogy, oceanography, limnology, soil science, geology and physical geography, and atmospheric science) to the study of the env... | Physical sciences | Earth science basics: General | Earth science |
16413778 | https://en.wikipedia.org/wiki/Ageing | Ageing | Ageing (or aging in American English) is the process of becoming older. The term refers mainly to humans, many other animals, and fungi, whereas for example, bacteria, perennial plants and some simple animals are potentially biologically immortal. In a broader sense, ageing can refer to single cells within an organism ... | Biology and health sciences | Health, fitness, and medicine | null |
9649191 | https://en.wikipedia.org/wiki/Suicide%20crisis | Suicide crisis | A suicide crisis, suicidal crisis or potential suicide is a situation in which a person is attempting to kill themselves or is seriously contemplating or planning to do so. It is considered by public safety authorities, medical practice, and emergency services to be a medical emergency, requiring immediate suicide inte... | Biology and health sciences | Mental disorders | Health |
9650286 | https://en.wikipedia.org/wiki/Australian%20Lowline | Australian Lowline | The Australian Lowline is a modern Australian breed of small, polled beef cattle. It was the result of a selective breeding experiment using black Aberdeen Angus cattle at the Agricultural Research Centre of the Department of Agriculture of New South Wales at Trangie. It is among the smallest breeds of cattle, but is n... | Biology and health sciences | Miniature cattle | Animals |
7445870 | https://en.wikipedia.org/wiki/Coua | Coua | Couas are large, mostly terrestrial birds of the cuckoo family, endemic to the island of Madagascar.
Couas are reminiscent of African turacos when walking along tree branches, and they likewise feature brightly coloured bare skin around the eyes. Some resemble coucals in their habit of clambering through jungle while ... | Biology and health sciences | Cuculiformes and relatives | Animals |
11127278 | https://en.wikipedia.org/wiki/Pair-instability%20supernova | Pair-instability supernova | A pair-instability supernova is a type of supernova predicted to occur when pair production, the production of free electrons and positrons in the collision between atomic nuclei and energetic gamma rays, temporarily reduces the internal radiation pressure supporting a supermassive star's core against gravitational col... | Physical sciences | Stellar astronomy | Astronomy |
2283222 | https://en.wikipedia.org/wiki/Endohedral%20fullerene | Endohedral fullerene | Endohedral fullerenes, also called endofullerenes, are fullerenes that have additional atoms, ions, or clusters enclosed within their inner spheres. The first lanthanum C60 complex called La@C60 was synthesized in 1985. The @ (at sign) in the name reflects the notion of a small molecule trapped inside a shell. Two type... | Physical sciences | Supramolecular chemistry | Chemistry |
12107594 | https://en.wikipedia.org/wiki/Archispirostreptus%20gigas | Archispirostreptus gigas | Archispirostreptus gigas, known as the giant African millipede, shongololo or Bongololo, is the largest extant species of millipede, growing up to in length, in circumference. It has approximately 256 legs, although the number of legs changes with each molting so it can vary according to each individual.
It is a wid... | Biology and health sciences | Myriapoda | Animals |
12116844 | https://en.wikipedia.org/wiki/Poultry%20farming | Poultry farming | Poultry farming is the form of animal husbandry which raises domesticated birds such as chickens, ducks, turkeys and geese to produce meat or eggs for food. Poultry – mostly chickens – are farmed in great numbers. More than 60 billion chickens are killed for consumption annually. Chickens raised for eggs are known as ... | Technology | Animal husbandry | null |
13690575 | https://en.wikipedia.org/wiki/Solar%20power | Solar power | Solar power, also known as solar electricity, is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Solar panels use the photovoltaic effect to convert light into an electric current. Concentrated solar power systems use lenses... | Technology | Energy and fuel | null |
5708292 | https://en.wikipedia.org/wiki/Daeodon | Daeodon | Daeodon is an extinct genus of entelodont even-toed ungulates that inhabited North America about 29 to 15.97 million years ago during the latest Oligocene and earliest Miocene. The type species is Daeodon shoshonensis, described from a very fragmentary holotype by Cope. Some authors synonymize it with Dinohyus hollandi... | Biology and health sciences | Other artiodactyla | Animals |
5709567 | https://en.wikipedia.org/wiki/New%20Mexico%20whiptail | New Mexico whiptail | The New Mexico whiptail (Aspidoscelis neomexicanus) is a female-only species of lizard found in New Mexico and Arizona in the southwestern United States, and in Chihuahua in northern Mexico. It is the official state reptile of New Mexico. It is one of many lizard species known to be parthenogenetic. Individuals of the ... | Biology and health sciences | Lizards and other Squamata | Animals |
4283745 | https://en.wikipedia.org/wiki/Algebraic%20expression | Algebraic expression | In mathematics, an algebraic expression is an expression built up from constants (usually, algebraic numbers) variables, and the basic algebraic operations:
addition (+), subtraction (-), multiplication (×), division (÷), whole number powers, and roots (fractional powers).. For example, is an algebraic expression. Si... | Mathematics | Algebra: General | null |
4285650 | https://en.wikipedia.org/wiki/Nodosauridae | Nodosauridae | Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the sister taxon to the Ankylosauridae, some analyses recover it as a paraphylet... | Biology and health sciences | Ornitischians | Animals |
4286482 | https://en.wikipedia.org/wiki/Crangon%20crangon | Crangon crangon | Crangon crangon is a species of caridean shrimp found across the northeastern Atlantic Ocean. Its range extends from the White Sea in the north of Russia to the coast of Morocco, including the Baltic Sea, and appears also throughout the Mediterranean and Black Seas. Commercially important, it is fished mainly in the s... | Biology and health sciences | Shrimps and prawns | Animals |
3145063 | https://en.wikipedia.org/wiki/Stack%20interchange | Stack interchange | A directional interchange, colloquially known as a stack interchange, is a type of grade-separated junction between two controlled-access highways that allows for free-flowing movement to and from all directions of traffic. These interchanges eliminate the problems of weaving, have the highest vehicle capacity, and ve... | Technology | Road infrastructure | null |
3148933 | https://en.wikipedia.org/wiki/IUPAC%20nomenclature%20of%20inorganic%20chemistry | IUPAC nomenclature of inorganic chemistry | In chemical nomenclature, the IUPAC nomenclature of inorganic chemistry is a systematic method of naming inorganic chemical compounds, as recommended by the International Union of Pure and Applied Chemistry (IUPAC). It is published in Nomenclature of Inorganic Chemistry (which is informally called the Red Book). Ideall... | Physical sciences | Nomenclature | Chemistry |
8967165 | https://en.wikipedia.org/wiki/Multibody%20system | Multibody system | Multibody system is the study of the dynamic behavior of interconnected rigid or flexible bodies, each of which may undergo large translational and rotational displacements.
Introduction
The systematic treatment of the dynamic behavior of interconnected bodies has led to a large number of important multibody formali... | Mathematics | Dynamical systems | null |
8967210 | https://en.wikipedia.org/wiki/Flemish%20Giant%20rabbit | Flemish Giant rabbit | The Flemish Giant rabbit () is the largest breed of domestic rabbit (Oryctolagus cuniculus domesticus). They weigh 6.8 kilograms (15 lb) on average, though the largest ones can weigh up to 22 kilograms (49 lb). Historically they are a utility breed used for their fur and meat. In the modern day, they are no longer comm... | Biology and health sciences | Rabbits | Animals |
8967572 | https://en.wikipedia.org/wiki/Polyisoprene | Polyisoprene | Polyisoprene is strictly speaking a collective name for polymers that are produced by polymerization of isoprene. In practice polyisoprene is commonly used to refer to synthetic cis-1,4-polyisoprene, made by the industrial polymerisation of isoprene. Natural forms of polyisoprene are also used in substantial quantities... | Physical sciences | Polymers | Chemistry |
8971972 | https://en.wikipedia.org/wiki/Sea%20cave | Sea cave | A sea cave, is also known as a littoral cave, a type of cave formed primarily by the wave action of the sea. The primary process involved is erosion. Sea caves are found throughout the world, actively forming along present coastlines and as relict sea caves on former coastlines. Some of the largest wave-cut caves in ... | Physical sciences | Oceanic and coastal landforms | Earth science |
181334 | https://en.wikipedia.org/wiki/Discrete%20logarithm | Discrete logarithm | In mathematics, for given real numbers a and b, the logarithm logb a is a number x such that . Analogously, in any group G, powers bk can be defined for all integers k, and the discrete logarithm logb a is an integer k such that . In number theory, the more commonly used term is index: we can write x = indr a (mod m) (... | Mathematics | Modular arithmetic | null |
181554 | https://en.wikipedia.org/wiki/Period%204%20element | Period 4 element | A period 4 element is one of the chemical elements in the fourth row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical b... | Physical sciences | Periods | Chemistry |
181556 | https://en.wikipedia.org/wiki/Period%206%20element | Period 6 element | A period 6 element is one of the chemical elements in the sixth row (or period) of the periodic table of the chemical elements, including the lanthanides. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new ro... | Physical sciences | Periods | Chemistry |
181576 | https://en.wikipedia.org/wiki/Dao%20%28Chinese%20sword%29 | Dao (Chinese sword) | Dao (pronunciation: , English approximation: , Chinese: 刀; pinyin: dāo; jyutping: dou1) are single-edged Chinese swords, primarily used for slashing and chopping. They can be straight or curved. The most common form is also known as the Chinese sabre, although those with wider blades are sometimes referred to as Chine... | Technology | Swords | null |
181580 | https://en.wikipedia.org/wiki/Pinus%20sylvestris | Pinus sylvestris | Pinus sylvestris, the Scots pine (UK), Scotch pine (US), Baltic pine, or European red pine is a species of tree in the pine family Pinaceae that is native to Eurasia. It can readily be identified by its combination of fairly short, blue-green leaves and orange-red bark.
Description
Pinus sylvestris is an evergreen c... | Biology and health sciences | Pinaceae | Plants |
181627 | https://en.wikipedia.org/wiki/Tonfa | Tonfa | The tonfa (Okinawan: , lit. old man's staff / "crutch", also spelled as tongfa or tuifa, also known as T-baton) is a melee weapon with its origins in the armed component of Okinawan martial arts where it is known as the tunkua. It consists of a stick with a perpendicular handle attached a third of the way down the le... | Technology | Melee weapons | null |
181636 | https://en.wikipedia.org/wiki/Histrionic%20personality%20disorder | Histrionic personality disorder | Histrionic personality disorder (HPD) is defined by the American Psychiatric Association as a personality disorder characterized by a pattern of excessive attention-seeking behaviors, usually beginning in adolescence or early adulthood, including inappropriate seduction and an excessive desire for approval. People diag... | Biology and health sciences | Mental disorders | Health |
181823 | https://en.wikipedia.org/wiki/Turbojet | Turbojet | The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, and a turbine (that drives the compressor). The compressed air from the compressor... | Technology | Aircraft components | null |
181897 | https://en.wikipedia.org/wiki/Cliff | Cliff | At all geography and geology, a cliff or rock face is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs a... | Physical sciences | Fluvial landforms | null |
181905 | https://en.wikipedia.org/wiki/Escarpment | Escarpment | An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations.
The terms scarp and scarp face are often used interchangeably with escarpment. Some sources differentiate the two terms, with escarpment referring to the mar... | Physical sciences | Landforms: General | Earth science |
181983 | https://en.wikipedia.org/wiki/Fermi%20gas | Fermi gas | A Fermi gas is an idealized model, an ensemble of many non-interacting fermions. Fermions are particles that obey Fermi–Dirac statistics, like electrons, protons, and neutrons, and, in general, particles with half-integer spin. These statistics determine the energy distribution of fermions in a Fermi gas in thermal equ... | Physical sciences | States of matter | Physics |
182051 | https://en.wikipedia.org/wiki/Cave%20bear | Cave bear | The cave bear (Ursus spelaeus) is a prehistoric species of bear that lived in Europe and Asia during the Pleistocene and became extinct about 24,000 years ago during the Last Glacial Maximum.
Both the word cave and the scientific name spelaeus are used because fossils of this species were mostly found in caves. This r... | Biology and health sciences | Bears | Animals |
182146 | https://en.wikipedia.org/wiki/Orbital%20mechanics | Orbital mechanics | Orbital mechanics or astrodynamics is the application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets, satellites, and other spacecraft. The motion of these objects is usually calculated from Newton's laws of motion and the law of universal gravitation. Orbital mechanics... | Physical sciences | Orbital mechanics | null |
182205 | https://en.wikipedia.org/wiki/Forging | Forging | Forging is a manufacturing process involving the shaping of metal using localized compressive forces. The blows are delivered with a hammer (often a power hammer) or a die. Forging is often classified according to the temperature at which it is performed: cold forging (a type of cold working), warm forging, or hot fo... | Technology | Metallurgy | null |
182208 | https://en.wikipedia.org/wiki/Heat%20treating | Heat treating | Heat treating (or heat treatment) is a group of industrial, thermal and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatme... | Technology | Metallurgy | null |
182255 | https://en.wikipedia.org/wiki/Trench | Trench | A trench is a type of excavation or depression in the ground that is generally deeper than it is wide (as opposed to a swale or a bar ditch), and narrow compared with its length (as opposed to a simple hole or pit).
In geology, trenches result from erosion by rivers or by geological movement of tectonic plates. In ci... | Technology | Earthworks | null |
182283 | https://en.wikipedia.org/wiki/Miles%20per%20hour | Miles per hour | Miles per hour (mph, m.p.h., MPH, or mi/h) is a British imperial and United States customary unit of speed expressing the number of miles travelled in one hour. It is used in the United Kingdom, the United States, and a number of smaller countries, most of which are UK or US territories, or have close historical ties w... | Physical sciences | Speed | Basics and measurement |
182358 | https://en.wikipedia.org/wiki/Cubit | Cubit | The cubit is an ancient unit of length based on the distance from the elbow to the tip of the middle finger. It was primarily associated with the Sumerians, Egyptians, and Israelites. The term cubit is found in the Bible regarding Noah's Ark, the Ark of the Covenant, the Tabernacle, and Solomon's Temple. The common cub... | Physical sciences | Length and distance | null |
182451 | https://en.wikipedia.org/wiki/Ethylenediaminetetraacetic%20acid | Ethylenediaminetetraacetic acid | Ethylenediaminetetraacetic acid (EDTA), also called EDTA acid, is an aminopolycarboxylic acid with the formula [CH2N(CH2CO2H)2]2. This white, slightly water-soluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-soluble complexes even at neutral pH. It is thus used to dissolve ... | Physical sciences | Specific acids | Chemistry |
182500 | https://en.wikipedia.org/wiki/Microdictyon | Microdictyon | Microdictyon is an extinct armoured worm-like panarthropod coated with net-like scleritic plates, known from the Early Cambrian Maotianshan shale of Yunnan China and other parts of the world. Microdictyon is part of the ill-defined taxon – Lobopodia – that includes several other odd worm-like animals that resembling wo... | Biology and health sciences | Ecdysozoa | Animals |
182520 | https://en.wikipedia.org/wiki/Plesiosauroidea | Plesiosauroidea | Plesiosauroidea (; Greek: 'near, close to' and 'lizard') is an extinct clade of carnivorous marine reptiles. They have the snake-like longest neck to body ratio of any reptile. Plesiosauroids are known from the Jurassic and Cretaceous periods. After their discovery, some plesiosauroids were said to have resembled "... | Biology and health sciences | Prehistoric marine reptiles | Animals |
182664 | https://en.wikipedia.org/wiki/Surface-to-air%20missile | Surface-to-air missile | A surface-to-air missile (SAM), also known as a ground-to-air missile (GTAM) or surface-to-air guided weapon (SAGW), is a missile designed to be launched from the ground or the sea to destroy aircraft or other missiles. It is one type of anti-aircraft system; in modern armed forces, missiles have replaced most other fo... | Technology | Missiles | null |
182693 | https://en.wikipedia.org/wiki/Clock%20signal | Clock signal | In electronics and especially synchronous digital circuits, a clock signal (historically also known as logic beat) is an electronic logic signal (voltage or current) which oscillates between a high and a low state at a constant frequency and is used like a metronome to synchronize actions of digital circuits. In a syn... | Technology | Functional circuits | null |
182728 | https://en.wikipedia.org/wiki/De%20Havilland%20Comet | De Havilland Comet | The de Havilland DH.106 Comet is the world's first commercial jet airliner. Developed and manufactured by de Havilland in the United Kingdom, the Comet 1 prototype first flew in 1949. It features an aerodynamically clean design with four de Havilland Ghost turbojet engines buried in the wing roots, a pressurised cabin,... | Technology | Specific aircraft_2 | null |
182732 | https://en.wikipedia.org/wiki/Sedimentary%20basin | Sedimentary basin | Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock. They form when long-term subsidence creates a regional depression that provides accommodation space for accumu... | Physical sciences | Landforms | null |
182765 | https://en.wikipedia.org/wiki/Prussian%20blue | Prussian blue | Prussian blue (also known as Berlin blue, Brandenburg blue, Parisian and Paris blue) is a dark blue pigment produced by oxidation of ferrous ferrocyanide salts. It has the chemical formula . Turnbull's blue is essentially identical chemically, excepting that it has different impurities and particle sizes—because it is... | Physical sciences | Cyanide salts | Chemistry |
182783 | https://en.wikipedia.org/wiki/Stratigraphy | Stratigraphy | Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks.
Stratigraphy has three related subfields: lithostratigraphy (lithologic stratigraphy), biostratigraphy (biologic stratigraphy),... | Physical sciences | Geology | null |
182787 | https://en.wikipedia.org/wiki/Fault%20%28geology%29 | Fault (geology) | In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as th... | Physical sciences | Geology | null |
182890 | https://en.wikipedia.org/wiki/Kronecker%20delta | Kronecker delta | In mathematics, the Kronecker delta (named after Leopold Kronecker) is a function of two variables, usually just non-negative integers. The function is 1 if the variables are equal, and 0 otherwise:
or with use of Iverson brackets:
For example, because , whereas because .
The Kronecker delta appears naturally in m... | Mathematics | Specific functions | null |
182945 | https://en.wikipedia.org/wiki/Ephedrine | Ephedrine | Ephedrine is a central nervous system (CNS) stimulant and sympathomimetic agent that is often used to prevent low blood pressure during anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion. It can be taken by mouth or by i... | Biology and health sciences | Specific drugs | Health |
183048 | https://en.wikipedia.org/wiki/Thrombosis | Thrombosis | Thrombosis () is the formation of a blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (thrombocytes) and fibrin to form a blood clot to prevent blood loss. Even when a blood vessel is not injured... | Biology and health sciences | Cardiovascular disease | Health |
183083 | https://en.wikipedia.org/wiki/Galaxy%20rotation%20curve | Galaxy rotation curve | The rotation curve of a disc galaxy (also called a velocity curve) is a plot of the orbital speeds of visible stars or gas in that galaxy versus their radial distance from that galaxy's centre. It is typically rendered graphically as a plot, and the data observed from each side of a spiral galaxy are generally asymmetr... | Physical sciences | Basics_2 | Astronomy |
183089 | https://en.wikipedia.org/wiki/List%20of%20unsolved%20problems%20in%20physics | List of unsolved problems in physics | The following is a list of notable unsolved problems grouped into broad areas of physics.
Some of the major unsolved problems in physics are theoretical, meaning that existing theories seem incapable of explaining a certain observed phenomenon or experimental result. The others are experimental, meaning that there is ... | Physical sciences | Physics basics: General | Physics |
183143 | https://en.wikipedia.org/wiki/Frigatebird | Frigatebird | Frigatebirds are a family of seabirds called Fregatidae which are found across all tropical and subtropical oceans. The five extant species are classified in a single genus, Fregata. All have predominantly black plumage, long, deeply forked tails and long hooked bills. Females have white underbellies and males have a d... | Biology and health sciences | Pelecanimorphae | null |
183193 | https://en.wikipedia.org/wiki/Front-side%20bus | Front-side bus | The front-side bus (FSB) is a computer communication interface (bus) that was often used in Intel-chip-based computers during the 1990s and 2000s. The EV6 bus served the same function for competing AMD CPUs. Both typically carry data between the central processing unit (CPU) and a memory controller hub, known as the n... | Technology | Computer hardware | null |
183243 | https://en.wikipedia.org/wiki/Alluvium | Alluvium | Alluvium (, ) is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluvium is also sometimes called alluvial deposit. Alluvium is typically geologically young and is not consolidated into solid rock. Sedimen... | Physical sciences | Sedimentology | Earth science |
183256 | https://en.wikipedia.org/wiki/Nuclear%20isomer | Nuclear isomer | A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). "Metastable" describes nuclei whose excited states have half-lives 100 to 1000 times longer than the half-lives of the excited nuclear states that decay wi... | Physical sciences | Nuclear physics | Physics |
183290 | https://en.wikipedia.org/wiki/Life%20extension | Life extension | Life extension is the concept of extending the human lifespan, either modestly through improvements in medicine or dramatically by increasing the maximum lifespan beyond its generally-settled biological limit of around 125 years. Several researchers in the area, along with "life extensionists", "immortalists", or "long... | Biology and health sciences | Fields of medicine | Health |
183324 | https://en.wikipedia.org/wiki/Thermodynamic%20activity | Thermodynamic activity | In thermodynamics, activity (symbol ) is a measure of the "effective concentration" of a species in a mixture, in the sense that the species' chemical potential depends on the activity of a real solution in the same way that it would depend on concentration for an ideal solution. The term "activity" in this sense was ... | Physical sciences | Thermodynamics | Chemistry |
183340 | https://en.wikipedia.org/wiki/Bicycle%20brake | Bicycle brake | A bicycle brake reduces the speed of a bicycle or prevents the wheels from moving. The two main types are: rim brakes and disc brakes. Drum brakes are less common on bicycles.
Most bicycle brake systems consist of three main components: a mechanism for the rider to apply the brakes, such as brake levers or pedals; a m... | Technology | Human-powered transport | null |
183351 | https://en.wikipedia.org/wiki/Penny-farthing | Penny-farthing | The penny-farthing, also known as a high wheel, high wheeler or ordinary, is an early type of bicycle. It was popular in the 1870s and 1880s, with its large front wheel providing high speeds, owing to it travelling a large distance for every rotation of the wheel. These bicycles had solid rubber tires and as a conseque... | Technology | Human-powered transport | null |
183481 | https://en.wikipedia.org/wiki/New%20World%20vulture | New World vulture | Cathartidae, known commonly as New World vultures or condors, are a family of birds of prey consisting of seven extant species in five genera. It includes five extant vultures and two extant condors found in the Americas. They are known as "New World" vultures to distinguish them from Old World vultures, with which the... | Biology and health sciences | Accipitriformes and Falconiformes | null |
183555 | https://en.wikipedia.org/wiki/Hypericum%20perforatum | Hypericum perforatum | Hypericum perforatum, commonly known as St John's wort (sometimes perforate St John's wort or common St John's wort), is a flowering plant in the family Hypericaceae. It is a perennial plant that grows up to tall, with many yellow flowers that have clearly visible black glands around their edges, long stamens (male re... | Biology and health sciences | Malpighiales | Plants |
183701 | https://en.wikipedia.org/wiki/Radiolaria | Radiolaria | The Radiolaria, also called Radiozoa, are unicellular eukaryotes of diameter 0.1–0.2 mm that produce intricate mineral skeletons, typically with a central capsule dividing the cell into the inner and outer portions of endoplasm and ectoplasm. The elaborate mineral skeleton is usually made of silica. They are found as z... | Biology and health sciences | SAR supergroup | Plants |
183751 | https://en.wikipedia.org/wiki/Primality%20test | Primality test | A primality test is an algorithm for determining whether an input number is prime. Among other fields of mathematics, it is used for cryptography. Unlike integer factorization, primality tests do not generally give prime factors, only stating whether the input number is prime or not. Factorization is thought to be a co... | Mathematics | Prime numbers | null |
183824 | https://en.wikipedia.org/wiki/Sonic%20boom | Sonic boom | A sonic boom is a sound associated with shock waves created when an object travels through the air faster than the speed of sound. Sonic booms generate enormous amounts of sound energy, sounding similar to an explosion or a thunderclap to the human ear.
The crack of a supersonic bullet passing overhead or the crack of... | Physical sciences | Waves | Physics |
183884 | https://en.wikipedia.org/wiki/Rhombus | Rhombus | In plane Euclidean geometry, a rhombus (: rhombi or rhombuses) is a quadrilateral whose four sides all have the same length. Another name is equilateral quadrilateral, since equilateral means that all of its sides are equal in length. The rhombus is often called a "diamond", after the diamonds suit in playing cards whi... | Mathematics | Two-dimensional space | null |
183932 | https://en.wikipedia.org/wiki/T%20Tauri%20star | T Tauri star | T Tauri stars (TTS) are a class of variable stars that are less than about ten million years old. This class is named after the prototype, T Tauri, a young star in the Taurus star-forming region. They are found near molecular clouds and identified by their optical variability and strong chromospheric lines. T Tauri s... | Physical sciences | Stellar astronomy | Astronomy |
183934 | https://en.wikipedia.org/wiki/Stellar%20wind | Stellar wind | A stellar wind is a flow of gas ejected from the upper atmosphere of a star. It is distinguished from the bipolar outflows characteristic of young stars by being less collimated, although stellar winds are not generally spherically symmetric.
Different types of stars have different types of stellar winds.
Post-main-s... | Physical sciences | Stellar astronomy | Astronomy |
183957 | https://en.wikipedia.org/wiki/Subsidence | Subsidence | Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope movement.
Processes that lead to subsidence include dissolution of underlying c... | Physical sciences | Geomorphology: General | Earth science |
183968 | https://en.wikipedia.org/wiki/Ibis | Ibis | The ibis () (collective plural ibises; classical plurals ibides and ibes) are a group of long-legged wading birds in the family Threskiornithidae that inhabit wetlands, forests and plains. "Ibis" derives from the Latin and Ancient Greek word for this group of birds. It also occurs in the scientific name of the western ... | Biology and health sciences | Pelecanimorphae | null |
183970 | https://en.wikipedia.org/wiki/Aragonite | Aragonite | Aragonite is a carbonate mineral and one of the three most common naturally occurring crystal forms of calcium carbonate (), the others being calcite and vaterite. It is formed by biological and physical processes, including precipitation from marine and freshwater environments.
The crystal lattice of aragonite differ... | Physical sciences | Minerals | Earth science |
184000 | https://en.wikipedia.org/wiki/Hysteria | Hysteria | Hysteria is a term used to mean ungovernable emotional excess and can refer to a temporary state of mind or emotion. In the nineteenth century, female hysteria was considered a diagnosable physical illness in women. It is assumed that the basis for diagnosis operated under the belief that women are predisposed to menta... | Biology and health sciences | Outdated disorders | Health |
184021 | https://en.wikipedia.org/wiki/Fynbos | Fynbos | Fynbos (; , ) is a small belt of natural shrubland or heathland vegetation located in the Western Cape and Eastern Cape provinces of South Africa. The area is predominantly coastal and mountainous, with a Mediterranean climate and rainy winters. The fynbos ecoregion is within the Mediterranean forests, woodlands, and s... | Physical sciences | Biomes: General | Earth science |
184120 | https://en.wikipedia.org/wiki/Time%20hierarchy%20theorem | Time hierarchy theorem | In computational complexity theory, the time hierarchy theorems are important statements about time-bounded computation on Turing machines. Informally, these theorems say that given more time, a Turing machine can solve more problems. For example, there are problems that can be solved with n2 time but not n time, where... | Mathematics | Complexity theory | null |
184300 | https://en.wikipedia.org/wiki/Brookite | Brookite | Brookite is the orthorhombic variant of titanium dioxide (TiO2), which occurs in four known natural polymorphic forms (minerals with the same composition but different structure). The other three of these forms are akaogiite (monoclinic), anatase (tetragonal) and rutile (tetragonal). Brookite is rare compared to anata... | Physical sciences | Minerals | Earth science |
184306 | https://en.wikipedia.org/wiki/Perovskite%20%28structure%29 | Perovskite (structure) | A perovskite is any material of formula ABX3 with a crystal structure similar to that of the mineral perovskite, which consists of calcium titanium oxide (CaTiO3). The mineral was first discovered in the Ural mountains of Russia by Gustav Rose in 1839 and named after Russian mineralogist L. A. Perovski (1792–1856). 'A'... | Physical sciences | Crystallography | Physics |
184324 | https://en.wikipedia.org/wiki/Lepidolite | Lepidolite | Lepidolite is a lilac-gray or rose-colored member of the mica group of minerals with chemical formula . It is the most abundant lithium-bearing mineral and is a secondary source of this metal. It is the major source of the alkali metal rubidium.
Lepidolite is found with other lithium-bearing minerals, such as spodumen... | Physical sciences | Silicate minerals | Earth science |
184325 | https://en.wikipedia.org/wiki/Spodumene | Spodumene | Spodumene is a pyroxene mineral consisting of lithium aluminium inosilicate, LiAl(SiO3)2, and is a commercially important source of lithium. It occurs as colorless to yellowish, purplish, or lilac kunzite (see below), yellowish-green or emerald-green hiddenite, prismatic crystals, often of great size. Single crystals o... | Physical sciences | Silicate minerals | Earth science |
1061346 | https://en.wikipedia.org/wiki/Allium%20fistulosum | Allium fistulosum | Allium fistulosum, the Welsh onion, also commonly called bunching onion, long green onion, Japanese bunching onion, and spring onion, is a species of perennial plant, often considered to be a kind of scallion.
The species is very similar in taste and odor to the related common onion, Allium cepa, and hybrids between t... | Biology and health sciences | Leafy vegetables | Plants |
1062339 | https://en.wikipedia.org/wiki/Polynesian%20rat | Polynesian rat | The Polynesian rat, Pacific rat or little rat (Rattus exulans), or , is the third most widespread species of rat in the world behind the brown rat and black rat. Contrary to its vernacular name, the Polynesian rat originated in Southeast Asia, and like its relatives has become widespread, migrating to most of Polynesia... | Biology and health sciences | Rodents | Animals |
1063435 | https://en.wikipedia.org/wiki/Normal%20force | Normal force | In mechanics, the normal force is the component of a contact force that is perpendicular to the surface that an object contacts. In this instance normal is used in the geometric sense and means perpendicular, as opposed to the meaning "ordinary" or "expected". A person standing still on a platform is acted upon by gr... | Physical sciences | Classical mechanics | Physics |
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