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1859894
https://en.wikipedia.org/wiki/Olefin%20metathesis
Olefin metathesis
In organic chemistry, olefin metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often creates fewer undesired by-products and hazardous wastes than...
Physical sciences
Organic reactions
Chemistry
6207163
https://en.wikipedia.org/wiki/Seismic%20magnitude%20scales
Seismic magnitude scales
Seismic magnitude scales are used to describe the overall strength or "size" of an earthquake. These are distinguished from seismic intensity scales that categorize the intensity or severity of ground shaking (quaking) caused by an earthquake at a given location. Magnitudes are usually determined from measurements of a...
Physical sciences
Seismology
Earth science
23783987
https://en.wikipedia.org/wiki/Roentgen%20%28unit%29
Roentgen (unit)
The roentgen or röntgen (; symbol R) is a legacy unit of measurement for the exposure of X-rays and gamma rays, and is defined as the electric charge freed by such radiation in a specified volume of air divided by the mass of that air (statcoulomb per kilogram). In 1928, it was adopted as the first international measur...
Physical sciences
Exposure
Basics and measurement
4749757
https://en.wikipedia.org/wiki/Geminal
Geminal
In chemistry, the descriptor geminal () refers to the relationship between two atoms or functional groups that are attached to the same atom. A geminal diol, for example, is a diol (a molecule that has two alcohol functional groups) attached to the same carbon atom, as in methanediol. Also the shortened prefix gem may...
Physical sciences
Concepts_2
Chemistry
4752147
https://en.wikipedia.org/wiki/Isenthalpic%20process
Isenthalpic process
An isenthalpic process or isoenthalpic process is a process that proceeds without any change in enthalpy, H; or specific enthalpy, h. Overview If a steady-state, steady-flow process is analysed using a control volume, everything outside the control volume is considered to be the surroundings. Such a process will be i...
Physical sciences
Thermodynamics
Physics
19609175
https://en.wikipedia.org/wiki/Arctodus
Arctodus
Arctodus is an extinct genus of short-faced bear that inhabited North America during the Pleistocene (~2.5 Mya until 12,800 years ago). There are two recognized species: the lesser short-faced bear (Arctodus pristinus) and the giant short-faced bear (Arctodus simus). Of these species, A. simus was larger, is known from...
Biology and health sciences
Bears
Animals
19612238
https://en.wikipedia.org/wiki/Public%20transport%20bus%20service
Public transport bus service
Public transport bus services are generally based on regular operation of transit buses along a route calling at agreed bus stops according to a published public transport timetable. History of buses Origins While there are indications of experiments with public transport in Paris as early as 1662, there is evidence...
Technology
Motorized road transport
null
19616384
https://en.wikipedia.org/wiki/Abstract%20algebra
Abstract algebra
In mathematics, more specifically algebra, abstract algebra or modern algebra is the study of algebraic structures, which are sets with specific operations acting on their elements. Algebraic structures include groups, rings, fields, modules, vector spaces, lattices, and algebras over a field. The term abstract algebra...
Mathematics
Algebra
null
19620261
https://en.wikipedia.org/wiki/Ur%20%28continent%29
Ur (continent)
Ur is a hypothetical supercontinent that formed in the Archean eon around 3.1 billion years ago (Ga). In a reconstruction by Rogers, Ur is half a billion years older than Arctica and, in the early period of its existence, probably the only continent on Earth, making it a supercontinent despite probably being smaller th...
Physical sciences
Paleogeography
Earth science
259906
https://en.wikipedia.org/wiki/Theorema%20Egregium
Theorema Egregium
Gauss's Theorema Egregium (Latin for "Remarkable Theorem") is a major result of differential geometry, proved by Carl Friedrich Gauss in 1827, that concerns the curvature of surfaces. The theorem says that Gaussian curvature can be determined entirely by measuring angles, distances and their rates on a surface, withou...
Mathematics
Other
null
259962
https://en.wikipedia.org/wiki/Avoirdupois
Avoirdupois
Avoirdupois (; abbreviated avdp.) is a measurement system of weights that uses pounds and ounces as units.<ref name=sizes /> It was first commonly used in the 13th century AD and was updated in 1959. In 1959, by international agreement, the definitions of the pound and ounce became standardized in countries which use...
Physical sciences
Measurement systems
Basics and measurement
778700
https://en.wikipedia.org/wiki/Laws%20of%20thermodynamics
Laws of thermodynamics
The laws of thermodynamics are a set of scientific laws which define a group of physical quantities, such as temperature, energy, and entropy, that characterize thermodynamic systems in thermodynamic equilibrium. The laws also use various parameters for thermodynamic processes, such as thermodynamic work and heat, and ...
Physical sciences
Thermodynamics
null
779725
https://en.wikipedia.org/wiki/Red%20deer
Red deer
The red deer (Cervus elaphus) is one of the largest deer species. A male red deer is called a stag or hart, and a female is called a doe or hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Iran, and parts of western Asia. It also inhabits the Atlas Mountains of Northern Africa; being...
Biology and health sciences
Artiodactyla
null
780166
https://en.wikipedia.org/wiki/Menstrual%20pad
Menstrual pad
A menstrual pad is an absorbent item worn in the underwear when menstruating, bleeding after giving birth, recovering from gynecologic surgery, experiencing a miscarriage or abortion, or in any other situation where it is necessary to absorb a flow of blood from the vagina. A menstrual pad is a type of menstrual hygien...
Biology and health sciences
Hygiene products
Health
780489
https://en.wikipedia.org/wiki/Thylacoleo
Thylacoleo
Thylacoleo ("pouch lion") is an extinct genus of carnivorous marsupials that lived in Australia from the late Pliocene to the Late Pleistocene (until around 40,000 years ago), often known as marsupial lions. They were the largest and last members of the family Thylacoleonidae, occupying the position of apex predator wi...
Biology and health sciences
Diprotodontia
Animals
780629
https://en.wikipedia.org/wiki/Non-volatile%20memory
Non-volatile memory
Non-volatile memory (NVM) or non-volatile storage is a type of computer memory that can retain stored information even after power is removed. In contrast, volatile memory needs constant power in order to retain data. Non-volatile memory typically refers to storage in memory chips, which store data in floating-gate me...
Technology
Non-volatile memory
null
780960
https://en.wikipedia.org/wiki/Software%20maintenance
Software maintenance
Software maintenance is the modification of software after delivery. Software maintenance is often considered lower skilled and less rewarding than new development. As such, it is a common target for outsourcing or offshoring. Usually, the team developing the software is different from those who will be maintaining it...
Technology
Software development: General
null
782310
https://en.wikipedia.org/wiki/Geological%20hazard
Geological hazard
A geologic hazard or geohazard is an adverse geologic condition capable of causing widespread damage or loss of property and life. These hazards are geological and environmental conditions and involve long-term or short-term geological processes. Geohazards can be relatively small features, but they can also attain hug...
Physical sciences
Geology: General
Earth science
782427
https://en.wikipedia.org/wiki/Cone
Cone
A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex that is not contained in the base. A cone is formed by a set of line segments, half-lines, or lines connecting a common point, the apex, to all of the ...
Mathematics
Three-dimensional space
null
22284121
https://en.wikipedia.org/wiki/Variable%20%28computer%20science%29
Variable (computer science)
In computer programming, a variable is an abstract storage location paired with an associated symbolic name, which contains some known or unknown quantity of data or object referred to as a value; or in simpler terms, a variable is a named container for a particular set of bits or type of data (like integer, float, str...
Technology
Software development: General
null
22284647
https://en.wikipedia.org/wiki/Real-valued%20function
Real-valued function
In mathematics, a real-valued function is a function whose values are real numbers. In other words, it is a function that assigns a real number to each member of its domain. Real-valued functions of a real variable (commonly called real functions) and real-valued functions of several real variables are the main objec...
Mathematics
Functions: General
null
18575446
https://en.wikipedia.org/wiki/Civil%20aviation
Civil aviation
Civil aviation is one of two major categories of flying, representing all non-military and non-state aviation, which can be both private and commercial. Most countries in the world are members of the International Civil Aviation Organization and work together to establish common Standards and Recommended Practices for...
Technology
Concepts of aviation
null
23785293
https://en.wikipedia.org/wiki/Mensa%20%28constellation%29
Mensa (constellation)
Mensa is a constellation in the Southern Celestial Hemisphere near the south celestial pole, one of fourteen constellations drawn up in the 18th century by French astronomer Nicolas-Louis de Lacaille. Its name is Latin for table, though it originally commemorated Table Mountain and was known as "Mons Mensae". One of th...
Physical sciences
Other
Astronomy
10575816
https://en.wikipedia.org/wiki/Tropical%20cyclone%20forecasting
Tropical cyclone forecasting
Tropical cyclone forecasting is the science of forecasting where a tropical cyclone's center, and its effects, are expected to be at some point in the future. There are several elements to tropical cyclone forecasting: track forecasting, intensity forecasting, rainfall forecasting, storm surge, tornado, and seasonal fo...
Physical sciences
Storms
Earth science
2585991
https://en.wikipedia.org/wiki/Ehrenfest%20theorem
Ehrenfest theorem
The Ehrenfest theorem, named after Austrian theoretical physicist Paul Ehrenfest, relates the time derivative of the expectation values of the position and momentum operators x and p to the expectation value of the force on a massive particle moving in a scalar potential , The Ehrenfest theorem is a special case of a ...
Physical sciences
Quantum mechanics
Physics
2588077
https://en.wikipedia.org/wiki/Handrail
Handrail
A handrail is a rail that is designed to be grasped by the hand so as to provide safety or support. In Britain, handrails are referred to as banisters. Handrails are commonly used while ascending or descending stairways and escalators in order to prevent injurious falls, and to provide bodily support in bathrooms or si...
Technology
Architectural elements
null
2588079
https://en.wikipedia.org/wiki/Guard%20rail
Guard rail
Guard rails, guardrails, railings or protective guarding, in general, are a boundary feature and may be a means to prevent or deter access to dangerous or off-limits areas while allowing light and visibility in a greater way than a fence. Common shapes are flat, rounded edge, and tubular in horizontal railings, wherea...
Technology
Architectural elements
null
2589115
https://en.wikipedia.org/wiki/NAND%20gate
NAND gate
In digital electronics, a NAND gate (NOT-AND) is a logic gate which produces an output which is false only if all its inputs are true; thus its output is complement to that of an AND gate. A LOW (0) output results only if all the inputs to the gate are HIGH (1); if any input is LOW (0), a HIGH (1) output results. A NAN...
Technology
Digital logic
null
6214456
https://en.wikipedia.org/wiki/Evolution%20of%20spiders
Evolution of spiders
Spiders have existed since at least 380 million years. The group's origins lie within an arachnid sub-group defined by the presence of book lungs (the tetrapulmonates); the arachnids as a whole evolved from aquatic chelicerate ancestors. More than 45,000 extant species have been described, organised taxonomically in 3,...
Biology and health sciences
Basics_4
Biology
6221709
https://en.wikipedia.org/wiki/Cold%20wave
Cold wave
A cold wave (known in some regions as a cold snap, cold spell or Arctic Snap) is a weather phenomenon that is distinguished by a cooling of the air. Specifically, as used by the U.S. National Weather Service, a cold wave is a rapid fall in temperature within a 24-hour period requiring substantially increased protection...
Physical sciences
Seasons
Earth science
19625172
https://en.wikipedia.org/wiki/Ocean%20surface%20topography
Ocean surface topography
Ocean surface topography or sea surface topography, also called ocean dynamic topography, are highs and lows on the ocean surface, similar to the hills and valleys of Earth's land surface depicted on a topographic map. These variations are expressed in terms of average sea surface height (SSH) relative to Earth's geoi...
Physical sciences
Oceanography
Earth science
19629283
https://en.wikipedia.org/wiki/Human%20anus
Human anus
In humans, the anus (: anuses or ani; from Latin ānus, "ring", "circle") is the external opening of the rectum located inside the intergluteal cleft. Two sphincters control the exit of feces from the body during an act of defecation, which is the primary function of the anus. These are the internal anal sphincter and t...
Biology and health sciences
Human anatomy
Health
19629444
https://en.wikipedia.org/wiki/Kagu
Kagu
The kagu or cagou (Rhynochetos jubatus) is a crested, long-legged, and bluish-grey bird endemic to the dense mountain forests of New Caledonia. It is the only surviving member of the genus Rhynochetos and the family Rhynochetidae, although a second species has been described from the fossil record. Measuring in lengt...
Biology and health sciences
Basics
Animals
19630671
https://en.wikipedia.org/wiki/Laurentia
Laurentia
Laurentia or the North American Craton is a large continental craton that forms the ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of North America, although originally it also included the cratonic areas of Greenland and the Hebridean...
Physical sciences
Paleogeography
Earth science
19630739
https://en.wikipedia.org/wiki/Continent
Continent
A continent is any of several large geographical regions. Continents are generally identified by convention rather than any strict criteria. A continent could be a single landmass or a part of a very large landmass, as in the case of Asia or Europe. Due to this, the number of continents varies; up to seven or as few as...
Physical sciences
Continents and regions
null
23649300
https://en.wikipedia.org/wiki/Opuntia
Opuntia
Opuntia, commonly called the prickly pear cactus, is a genus of flowering plants in the cactus family Cactaceae, many known for their flavorful fruit and showy flowers. Cacti are well-adapted to aridity; however, they are still vulnerable to alterations in precipitation and temperature driven by climate change. Prickly...
Biology and health sciences
Other culinary fruits
Plants
3531757
https://en.wikipedia.org/wiki/King%20quail
King quail
The king quail (Synoicus chinensis), also known as the blue-breasted quail, Asian blue quail, Chinese painted quail, or Chung-Chi, is a species of Old World quail in the family Phasianidae. This species is the smallest "true quail", ranging in the wild from southern China, South and Southeast Asia to Oceania, south to ...
Biology and health sciences
Galliformes
Animals
3533321
https://en.wikipedia.org/wiki/Amargasaurus
Amargasaurus
Amargasaurus (; "La Amarga lizard") is a genus of sauropod dinosaur from the Early Cretaceous epoch (129.4–122.46 mya) of what is now Argentina. The only known skeleton was discovered in 1984 and is virtually complete, including a fragmentary skull, making Amargasaurus one of the best-known sauropods of its epoch. Amar...
Biology and health sciences
Sauropods
Animals
3535484
https://en.wikipedia.org/wiki/Saffron%20%28color%29
Saffron (color)
Saffron is a shade of yellow or orange, the colour of the tip of the saffron crocus thread, from which the spice saffron is derived. The hue of the spice saffron is primarily due to the carotenoid chemical crocin. Etymology The word saffron ultimately derives (via Arabic) from the Middle Iranian ja'far-. The name was...
Physical sciences
Colors
Physics
1244402
https://en.wikipedia.org/wiki/Gas%20balloon
Gas balloon
A gas balloon is a balloon that rises and floats in the air because it is filled with a gas lighter than air (such as helium or hydrogen). When not in flight, it is tethered to prevent it from flying away and is sealed at the bottom to prevent the escape of gas. A gas balloon may also be called a Charlière for its inve...
Technology
Types of aircraft
null
1244926
https://en.wikipedia.org/wiki/Graveyard%20orbit
Graveyard orbit
A graveyard orbit, also called a junk orbit or disposal orbit, is an orbit that lies away from common operational orbits. One significant graveyard orbit is a supersynchronous orbit well beyond geosynchronous orbit. Some satellites are moved into such orbits at the end of their operational life to reduce the probabilit...
Physical sciences
Orbital mechanics
Astronomy
1245859
https://en.wikipedia.org/wiki/Fayalite
Fayalite
Fayalite (, commonly abbreviated to Fa) is the iron-rich end-member of the olivine solid-solution series. In common with all minerals in the olivine group, fayalite crystallizes in the orthorhombic system (space group Pbnm) with cell parameters a 4.82 Å, b 10.48 Å and c 6.09 Å. Fayalite forms solid solution series wit...
Physical sciences
Silicate minerals
Earth science
1246386
https://en.wikipedia.org/wiki/Unbibium
Unbibium
Unbibium, also known as element 122 or eka-thorium, is a hypothetical chemical element; it has placeholder symbol Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, which are used until the element is discovered, confirmed, and a permanent name is decided upon. ...
Physical sciences
Periods
Chemistry
1246694
https://en.wikipedia.org/wiki/Chinese%20alligator
Chinese alligator
The Chinese alligator (; ), also known as the Yangtze alligator (), China alligator, or historically the muddy dragon, is a crocodilian endemic to China. It and the American alligator (A. mississippiensis) are the only living species in the genus Alligator of the family Alligatoridae. Dark gray or black in color with a...
Biology and health sciences
Crocodilia
Animals
1246718
https://en.wikipedia.org/wiki/Organic%20matter
Organic matter
Organic matter, organic material, or natural organic matter refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come from the feces and remains of organisms such as plants and animals. Organ...
Biology and health sciences
Biology basics
Biology
1246810
https://en.wikipedia.org/wiki/Humidifier
Humidifier
A humidifier is a household appliance or device designed to increase the moisture level in the air within a room or an enclosed space. It achieves this by emitting water droplets or steam into the surrounding air, thereby raising the humidity. In the home, point-of-use humidifiers are commonly used to humidify a singl...
Technology
Household appliances
null
1247265
https://en.wikipedia.org/wiki/Volume%20integral
Volume integral
In mathematics (particularly multivariable calculus), a volume integral (∭) is an integral over a 3-dimensional domain; that is, it is a special case of multiple integrals. Volume integrals are especially important in physics for many applications, for example, to calculate flux densities, or to calculate mass from a c...
Mathematics
Multivariable and vector calculus
null
1248929
https://en.wikipedia.org/wiki/Fetal%20alcohol%20spectrum%20disorder
Fetal alcohol spectrum disorder
Fetal alcohol spectrum disorders (FASDs) are a group of conditions that can occur in a person who is exposed to alcohol during gestation. FASD affects 1 in 20 Americans, but is highly mis- and under-diagnosed. The several forms of the condition (in order of most severe to least severe) are: fetal alcohol syndrome (FAS...
Biology and health sciences
Disabilities
Health
1249122
https://en.wikipedia.org/wiki/Water%20supply%20network
Water supply network
A water supply network or water supply system is a system of engineered hydrologic and hydraulic components that provide water supply. A water supply system typically includes the following: A drainage basin (see water purification – sources of drinking water) A raw water collection point (above or below ground) wher...
Technology
Food, water and health
null
15690011
https://en.wikipedia.org/wiki/Staphylococcal%20infection
Staphylococcal infection
A staphylococcal infection or staph infection is an infection caused by members of the Staphylococcus genus of bacteria. These bacteria commonly inhabit the skin and nose where they are innocuous, but may enter the body through cuts or abrasions which may be nearly invisible. Once inside the body, the bacteria may sp...
Biology and health sciences
Bacterial infections
Health
22293372
https://en.wikipedia.org/wiki/SAR%20supergroup
SAR supergroup
SAR or Harosa is a highly diverse clade of eukaryotes, often considered a supergroup, that includes stramenopiles (heterokonts), alveolates, and rhizarians. It is a node-based taxon, including all descendants of the three groups' last common ancestor, and comprises most of the now-rejected Chromalveolata. Their sister ...
Biology and health sciences
SAR supergroup
Plants
22295187
https://en.wikipedia.org/wiki/Epoch%20%28computing%29
Epoch (computing)
In computing, an epoch is a fixed date and time used as a reference from which a computer measures system time. Most computer systems determine time as a number representing the seconds removed from a particular arbitrary date and time. For instance, Unix and POSIX measure time as the number of seconds that have passed...
Technology
Computer architecture concepts
null
1860870
https://en.wikipedia.org/wiki/Environmental%20justice
Environmental justice
Environmental justice is a social movement that addresses injustice that occurs when poor or marginalized communities are harmed by hazardous waste, resource extraction, and other land uses from which they do not benefit. The movement has generated hundreds of studies showing that exposure to environmental harm is ineq...
Physical sciences
Earth science basics: General
Earth science
1863612
https://en.wikipedia.org/wiki/Normal-form%20game
Normal-form game
In game theory, normal form is a description of a game. Unlike extensive form, normal-form representations are not graphical per se, but rather represent the game by way of a matrix. While this approach can be of greater use in identifying strictly dominated strategies and Nash equilibria, some information is lost as c...
Mathematics
Game theory
null
1864670
https://en.wikipedia.org/wiki/Marine%20iguana
Marine iguana
The marine iguana (Amblyrhynchus cristatus), also known as the sea iguana, saltwater iguana, or Galápagos marine iguana, is a species of iguana found only on the Galápagos Islands (Ecuador). Unique among modern lizards, it is a marine reptile that has the ability to forage in the sea for algae, which makes up almost al...
Biology and health sciences
Iguania
Animals
1864695
https://en.wikipedia.org/wiki/Dracaena%20trifasciata
Dracaena trifasciata
Dracaena trifasciata is a species of flowering plant in the family Asparagaceae, native to tropical West Africa from Nigeria east to the Congo. It is most commonly known as the snake plant, Saint George's sword, mother-in-law's tongue, and viper's bowstring hemp, among other names. Until 2017, it was known under the sy...
Biology and health sciences
Asparagales
Plants
1864889
https://en.wikipedia.org/wiki/Cosmology
Cosmology
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe, the cosmos. The term cosmology was first used in English in 1656 in Thomas Blount's Glossographia, and in 1731 taken up in Latin by German philosopher Christian Wolff in Cosmologia Generalis. Religious or mythological cosmology...
Physical sciences
Astronomy basics
Astronomy
1865464
https://en.wikipedia.org/wiki/Carya%20ovata
Carya ovata
Carya ovata, the shagbark hickory, is a common hickory native to eastern North America, with two varieties. The trees can grow to quite a large size but are unreliable in their fruit output. The nut is consumed by wildlife and historically by Native Americans, who also used the wood. Name The word hickory is an apheti...
Biology and health sciences
Fagales
Plants
18579693
https://en.wikipedia.org/wiki/A%20value
A value
A-values are numerical values used in the determination of the most stable orientation of atoms in a molecule (conformational analysis), as well as a general representation of steric bulk. A-values are derived from energy measurements of the different cyclohexane conformations of a monosubstituted cyclohexane chemical....
Physical sciences
Stereochemistry
Chemistry
18580879
https://en.wikipedia.org/wiki/Transport
Transport
Transport (in British English) or transportation (in American English) is the intentional movement of humans, animals, and goods from one location to another. Modes of transport include air, land (rail and road), water, cable, pipelines, and space. The field can be divided into infrastructure, vehicles, and operations....
Technology
Technology
null
18581082
https://en.wikipedia.org/wiki/Tarantula
Tarantula
Tarantulas comprise a group of large and often hairy spiders of the family Theraphosidae. , 1,100 species have been identified, with 166 genera. The term "tarantula" is usually used to describe members of the family Theraphosidae, although many other members of the same infraorder (Mygalomorphae) are commonly referred ...
Biology and health sciences
Arachnids
null
18581278
https://en.wikipedia.org/wiki/Digit%20%28anatomy%29
Digit (anatomy)
A digit is one of several most distal parts of a limb, such as fingers or toes, present in many vertebrates. Names Some languages have different names for hand and foot digits (English: respectively "finger" and "toe", German: "Finger" and "Zeh", French: "doigt" and "orteil"). In other languages, e.g. Arabic, Russian...
Biology and health sciences
External anatomy and regions of the body
Biology
18581424
https://en.wikipedia.org/wiki/Silverfish
Silverfish
The silverfish (Lepisma saccharinum) is a species of small, primitive, wingless insect in the order Zygentoma (formerly Thysanura). Its common name derives from the insect's silvery light grey colour, combined with the fish-like appearance of its movements. The scientific name (L. saccharinum) indicates that the silver...
Biology and health sciences
Zygentoma
Animals
18582186
https://en.wikipedia.org/wiki/Benzene
Benzene
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constitu...
Physical sciences
Hydrocarbons
null
18582230
https://en.wikipedia.org/wiki/Methane
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it is diffi...
Physical sciences
Hydrocarbons
null
18582511
https://en.wikipedia.org/wiki/Alpaca
Alpaca
The alpaca (Lama pacos) is a species of South American camelid mammal. Traditionally, alpacas were kept in herds that grazed on the level heights of the Andes of Southern Peru, Western Bolivia, Ecuador, and Northern Chile. More recently, alpacas may be found on farms and ranches worldwide, with thousands of animals bo...
Biology and health sciences
Artiodactyla
null
18588994
https://en.wikipedia.org/wiki/Usenet
Usenet
Usenet (), USENET, or, "in full", User's Network, is a worldwide distributed discussion system available on computers. It was developed from the general-purpose Unix-to-Unix Copy (UUCP) dial-up network architecture. Tom Truscott and Jim Ellis conceived the idea in 1979, and it was established in 1980. Users read and po...
Technology
Internet
null
18589032
https://en.wikipedia.org/wiki/Particle%20accelerator
Particle accelerator
A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies to contain them in well-defined beams. Small accelerators are used for fundamental research in particle physics. Accelerators are also used as synchrotron light sources for the study of cond...
Physical sciences
Particle physics: General
null
18589212
https://en.wikipedia.org/wiki/Reverse%20osmosis
Reverse osmosis
Reverse osmosis (RO) is a water purification process that uses a semi-permeable membrane to separate water molecules from other substances. RO applies pressure to overcome osmotic pressure that favors even distributions. RO can remove dissolved or suspended chemical species as well as biological substances (principally...
Physical sciences
Other separations
Chemistry
468974
https://en.wikipedia.org/wiki/Fox%20Terrier
Fox Terrier
Fox Terriers are two different breeds of the terrier dog type: the Smooth Fox Terrier and the Wire Fox Terrier. Both of these breeds originated in the 19th century from a handful of dogs who are descended from earlier varieties of British terriers, and are related to other modern white terrier breeds. In addition, a nu...
Biology and health sciences
Dogs
Animals
469220
https://en.wikipedia.org/wiki/Frontal%20lobe
Frontal lobe
The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove between tissues called the central sulcus and from the temporal lobe by a deeper...
Biology and health sciences
Nervous system
Biology
469246
https://en.wikipedia.org/wiki/Lattice%20%28group%29
Lattice (group)
In geometry and group theory, a lattice in the real coordinate space is an infinite set of points in this space with the properties that coordinate-wise addition or subtraction of two points in the lattice produces another lattice point, that the lattice points are all separated by some minimum distance, and that ever...
Mathematics
Other
null
469304
https://en.wikipedia.org/wiki/Lattice%20%28order%29
Lattice (order)
A lattice is an abstract structure studied in the mathematical subdisciplines of order theory and abstract algebra. It consists of a partially ordered set in which every pair of elements has a unique supremum (also called a least upper bound or join) and a unique infimum (also called a greatest lower bound or meet). An...
Mathematics
Order theory
null
469343
https://en.wikipedia.org/wiki/Mandrill
Mandrill
The mandrill (Mandrillus sphinx) is a large Old World monkey native to west central Africa. It is one of the most colorful mammals in the world, with red and blue skin on its face and posterior. The species is sexually dimorphic, as males have a larger body, longer canine teeth and brighter coloring. It is the largest ...
Biology and health sciences
Old World monkeys
Animals
469646
https://en.wikipedia.org/wiki/Watercress
Watercress
Watercress or yellowcress (Nasturtium officinale) is a species of aquatic flowering plant in the cabbage family, Brassicaceae. Watercress is a rapidly growing perennial plant native to Eurasia. It is one of the oldest known leaf vegetables consumed by humans. Watercress and many of its relatives, such as garden cress,...
Biology and health sciences
Leafy vegetables
Plants
469661
https://en.wikipedia.org/wiki/Whiteboard
Whiteboard
A whiteboard (also known by marker board, dry-erase board, dry-wipe board, and pen-board) is a glossy, usually white surface for making non-permanent markings. Whiteboards are analogous to blackboards, but with a smoother surface allowing for rapid marking and erasing of markings on their surface. The popularity of whi...
Technology
Writing tools
null
469990
https://en.wikipedia.org/wiki/Whirlpool
Whirlpool
A whirlpool is a body of rotating water produced by opposing currents or a current running into an obstacle. Small whirlpools form when a bath or a sink is draining. More powerful ones formed in seas or oceans may be called maelstroms ( ). Vortex is the proper term for a whirlpool that has a downdraft. In narrow ocean...
Physical sciences
Water: General
Earth science
470323
https://en.wikipedia.org/wiki/Iron%28II%29%20oxide
Iron(II) oxide
Iron(II) oxide or ferrous oxide is the inorganic compound with the formula FeO. Its mineral form is known as wüstite. One of several iron oxides, it is a black-colored powder that is sometimes confused with rust, the latter of which consists of hydrated iron(III) oxide (ferric oxide). Iron(II) oxide also refers to a f...
Physical sciences
Oxide salts
Chemistry
470488
https://en.wikipedia.org/wiki/Pencil%20sharpener
Pencil sharpener
A pencil sharpener (or pencil pointer, or in Ireland a parer or topper) is a tool for sharpening a pencil's writing point by shaving away its worn surface. Pencil sharpeners may be operated manually or by an electric motor. It is common for many sharpeners to have a casing around them, which can be removed for emptying...
Technology
Writing tools
null
470605
https://en.wikipedia.org/wiki/Red%20junglefowl
Red junglefowl
The red junglefowl (Gallus gallus), also known as the Indian red junglefowl (and formerly the bankiva or bankiva-fowl), is a species of tropical, predominantly terrestrial bird in the fowl and pheasant family, Phasianidae, found across much of Southeast and parts of South Asia. The red junglefowl was the primary specie...
Biology and health sciences
Galliformes
Animals
470742
https://en.wikipedia.org/wiki/Keratitis
Keratitis
Keratitis is a condition in which the eye's cornea, the clear dome on the front surface of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves any of the following symptoms: pain, impaired eyesight, photophobia (light sensitivity), red eye and a 'gritty' sensation. ...
Biology and health sciences
Infectious diseases by site
Health
470752
https://en.wikipedia.org/wiki/Expectation%E2%80%93maximization%20algorithm
Expectation–maximization algorithm
In statistics, an expectation–maximization (EM) algorithm is an iterative method to find (local) maximum likelihood or maximum a posteriori (MAP) estimates of parameters in statistical models, where the model depends on unobserved latent variables. The EM iteration alternates between performing an expectation (E) step,...
Mathematics
Statistics
null
470843
https://en.wikipedia.org/wiki/Fight-or-flight%20response
Fight-or-flight response
The fight-or-flight or the fight-flight-freeze-or-fawn (also called hyperarousal or the acute stress response) is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It was first described by Walter Bradford Cannon in 1915. His theory states that animals react t...
Biology and health sciences
Ethology
Biology
471376
https://en.wikipedia.org/wiki/Pruning
Pruning
Pruning is a horticultural, arboricultural, and silvicultural practice involving the selective removal of certain parts of a plant, such as branches, buds, or roots. The practice entails the targeted removal of diseased, damaged, dead, non-productive, structurally unsound, or otherwise unwanted plant material from cro...
Technology
Horticulture
null
471385
https://en.wikipedia.org/wiki/Impatiens
Impatiens
Impatiens is a genus of more than 1,000 species of flowering plants, widely distributed throughout the Northern Hemisphere and the tropics. Together with the genus Hydrocera (one species), Impatiens make up the family Balsaminaceae. Common names in North America include impatiens, jewelweed, touch-me-not, snapweed an...
Biology and health sciences
Ericales
null
471476
https://en.wikipedia.org/wiki/Astronomical%20system%20of%20units
Astronomical system of units
The astronomical system of units, formerly called the IAU (1976) System of Astronomical Constants, is a system of measurement developed for use in astronomy. It was adopted by the International Astronomical Union (IAU) in 1976 via Resolution No. 1, and has been significantly updated in 1994 and 2009 (see Astronomical c...
Physical sciences
Measurement systems
Basics and measurement
471487
https://en.wikipedia.org/wiki/Cosmic%20distance%20ladder
Cosmic distance ladder
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A direct distance measurement of an astronomical object is possible only for those objects that are "close enough" (within about a thousand parsecs)...
Physical sciences
Astrometry
null
12840258
https://en.wikipedia.org/wiki/Nuclear%20envelope
Nuclear envelope
The nuclear envelope, also known as the nuclear membrane, is made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which encloses the genetic material. The nuclear envelope consists of two lipid bilayer membranes: an inner nuclear membrane and an outer nuclear membrane. The space betw...
Biology and health sciences
Organelles
Biology
12841199
https://en.wikipedia.org/wiki/Baton%20%28law%20enforcement%29
Baton (law enforcement)
A baton (also truncheon, nightstick, billy club, billystick, cosh, lathi, or simply stick) is a roughly cylindrical club made of wood, rubber, plastic, or metal. It is carried as a compliance tool and defensive weapon by law-enforcement officers, correctional staff, security guards and military personnel. The name bato...
Technology
Melee weapons
null
12844718
https://en.wikipedia.org/wiki/Dimorphic%20fungus
Dimorphic fungus
A dimorphic fungus is a fungus that can exist in the form of both mold and yeast. As this is usually brought about by a change in temperature, this fungus type is also described as a thermally dimorphic fungus. An example is Talaromyces marneffei, a human pathogen that grows as a mold at room temperature, and as a ...
Biology and health sciences
Basics
Plants
10592503
https://en.wikipedia.org/wiki/Charging%20station
Charging station
A charging station, also known as a charge point, chargepoint, or electric vehicle supply equipment (EVSE), is a power supply device that supplies electrical power for recharging plug-in electric vehicles (including battery electric vehicles, electric trucks, electric buses, neighborhood electric vehicles, and plug-in ...
Technology
Concepts of ground transport
null
19637796
https://en.wikipedia.org/wiki/Scarecrow
Scarecrow
A scarecrow is a decoy or mannequin that is often in the shape of a human. Humanoid scarecrows are usually dressed in old clothes and placed in open fields to discourage birds from disturbing and feeding on recently cast seed and growing crops. Scarecrows are used around the world by farmers, and are a notable symbol o...
Technology
Pest and disease control
null
19637950
https://en.wikipedia.org/wiki/Housefly
Housefly
The housefly (Musca domestica) is a fly of the suborder Cyclorrhapha. It possibly originated in the Middle East, and spread around the world as a commensal of humans. It is the most common fly species found in houses. Adults are gray to black, with four dark, longitudinal lines on the thorax, slightly hairy bodies, and...
Biology and health sciences
Flies (Diptera)
null
19637986
https://en.wikipedia.org/wiki/Gingivitis
Gingivitis
Gingivitis is a non-destructive disease that causes inflammation of the gums; ulitis is an alternative term. The most common form of gingivitis, and the most common form of periodontal disease overall, is in response to bacterial biofilms (also called plaque) that are attached to tooth surfaces, termed plaque-induced g...
Biology and health sciences
Specific diseases
Health
19644137
https://en.wikipedia.org/wiki/Mobile%20phone
Mobile phone
A mobile phone, or cell phone, is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones (landline phones). This radio frequency link connects to the switching systems of a mobile phone operator, ...
Technology
Media and communication
null
2589714
https://en.wikipedia.org/wiki/Milky%20Way
Milky Way
The Milky Way is the galaxy that includes the Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. The Milky Way is a barred spiral galaxy with a D25 isophotal diameter estimat...
Physical sciences
Astronomy
null
2589751
https://en.wikipedia.org/wiki/Fluorescence%20correlation%20spectroscopy
Fluorescence correlation spectroscopy
Fluorescence correlation spectroscopy (FCS) is a statistical analysis, via time correlation, of stationary fluctuations of the fluorescence intensity. Its theoretical underpinning originated from L. Onsager's regression hypothesis. The analysis provides kinetic parameters of the physical processes underlying the fluct...
Physical sciences
Spectroscopy
Chemistry
2590442
https://en.wikipedia.org/wiki/Square%20degree
Square degree
A square degree (deg2) is a non-SI unit measure of solid angle. Other denotations include sq. deg. and (°)2. Just as degrees are used to measure parts of a circle, square degrees are used to measure parts of a sphere. Analogous to one degree being equal to  radians, a square degree is equal to ()2 steradians (sr), or ...
Physical sciences
Solid angle
Basics and measurement
2592906
https://en.wikipedia.org/wiki/Planetary%20habitability
Planetary habitability
Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and maintain an environment hospitable to life. Life may be generated directly on a planet or satellite endogenously. Research suggests that life may also be transferred from one body to another, through a hypothetical pro...
Physical sciences
Planetary science
Astronomy
2592962
https://en.wikipedia.org/wiki/Octant%20%28instrument%29
Octant (instrument)
The octant, also called a reflecting quadrant, is a reflecting instrument used in navigation. Etymology The name octant derives from the Latin octans meaning eighth part of a circle, because the instrument's arc is one eighth of a circle. Reflecting quadrant derives from the instrument using mirrors to reflect the pa...
Technology
Navigation
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