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Cope's rule , named after American paleontologist Edward Drinker Cope , [ 1 ] [ 2 ] postulates that population lineages tend to increase in body size over evolutionary time. [ 3 ] It was never actually stated by Cope, although he favoured the occurrence of linear evolutionary trends . [ 4 ] It is sometimes also known a... | https://en.wikipedia.org/wiki/Cope's_rule |
The Cope reaction or Cope elimination , developed by Arthur C. Cope , is the elimination reaction of an N-oxide to an alkene and a hydroxylamine . [ 1 ] [ 2 ] [ 3 ] [ 4 ]
Typically, the amine oxide is prepared from the corresponding amine with a peroxy acid or comparable oxidant . The actual elimination requires just... | https://en.wikipedia.org/wiki/Cope_reaction |
The Cope rearrangement is an extensively studied organic reaction involving the [3,3]-sigmatropic rearrangement of 1,5- dienes . [ 1 ] [ 2 ] [ 3 ] [ 4 ] It was developed by Arthur C. Cope and Elizabeth Hardy . For example, 3-methyl-hexa-1,5-diene heated to 300 °C yields hepta-1,5-diene.
The Cope rearrangement causes t... | https://en.wikipedia.org/wiki/Cope_rearrangement |
The Copeland–Erdős constant is the concatenation of "0." with the base 10 representations of the prime numbers in order. Its value, using the modern definition of prime, [ 1 ] is approximately
The constant is irrational ; this can be proven with Dirichlet's theorem on arithmetic progressions or Bertrand's postulate (H... | https://en.wikipedia.org/wiki/Copeland–Erdős_constant |
Copepods ( / ˈ k oʊ p ə p ɒ d / ; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat . Some species are planktonic (living in the water column), some are benthic (living on the sediments), several species have parasitic phases , and some continental species may l... | https://en.wikipedia.org/wiki/Copepod |
The term " Copernican Revolution " was coined by the German philosopher Immanuel Kant in his 1781 work Critique of Pure Reason . It was the paradigm shift from the Ptolemaic model of the heavens, which described the cosmos as having Earth stationary at the center of the universe, to the heliocentric model with the Sun ... | https://en.wikipedia.org/wiki/Copernican_Revolution |
Copernican heliocentrism is the astronomical model developed by Nicolaus Copernicus and published in 1543. This model positioned the Sun at the center of the Universe , motionless, with Earth and the other planets orbiting around it in circular paths , modified by epicycles , and at uniform speeds. The Copernican model... | https://en.wikipedia.org/wiki/Copernican_heliocentrism |
In physical cosmology , the Copernican principle states that humans are not privileged observers of the universe , [ 1 ] that observations from the Earth are representative of observations from the average position in the universe. Named for Copernican heliocentrism , it is a working assumption that arises from a modif... | https://en.wikipedia.org/wiki/Copernican_principle |
In the clustering of biological information such as data from microarray experiments, the cophenetic similarity or cophenetic distance [ 1 ] of two objects is a measure of how similar those two objects have to be in order to be grouped into the same cluster. The cophenetic distance between two objects is the height of... | https://en.wikipedia.org/wiki/Cophenetic |
Given two interacting atoms A and B, the cophonicity ( / k oʊ f oʊ ˈ n ɪ s ɪ t i / ) of the A-B atomic pair is a measure of the overlap of the A and B contributions to a specific range of vibrational frequencies. In the field of condensed matter physics , cophonicity is a metric aimed at the parametrization of the dyna... | https://en.wikipedia.org/wiki/Cophonicity |
Copigmentation is a phenomenon where pigmentation due to anthocyanidins is reinforced by the presence of other colorless flavonoids known as cofactors or “copigments”. This occurs by the formation of a non-covalently-linked complex . [ 1 ]
An example is the bluish purple flowers of the Japanese garden iris ( Iris ensa... | https://en.wikipedia.org/wiki/Copigmentation |
Coping (from cope , Latin capa ) is the capping or covering of a wall . [ 1 ] A splayed or wedge coping is one that slopes in a single direction; a saddle coping slopes to either side of a central high point. [ 2 ]
Coping may be made of stone, brick , clay or terracotta , concrete or cast stone , tile , slate , wood, ... | https://en.wikipedia.org/wiki/Coping_(architecture) |
A copiotroph is an organism found in environments rich in nutrients , particularly carbon . They are the opposite to oligotrophs , which survive in much lower carbon concentrations. [ 1 ]
Copiotrophic organisms tend to grow in high organic substrate conditions. For example, copiotrophic organisms grow in Sewage lagoon... | https://en.wikipedia.org/wiki/Copiotroph |
In geometry , a set of points in space are coplanar if there exists a geometric plane that contains them all. For example, three points are always coplanar, and if the points are distinct and non-collinear , the plane they determine is unique. However, a set of four or more distinct points will, in general, not lie in ... | https://en.wikipedia.org/wiki/Coplanarity |
In polymer chemistry , a copolymer is a polymer derived from more than one species of monomer . The polymerization of monomers into copolymers is called copolymerization . Copolymers obtained from the copolymerization of two monomer species are sometimes called bipolymers . Those obtained from three and four monomers a... | https://en.wikipedia.org/wiki/Copolymer |
Copper(I) acetylide , copper carbide or cuprous acetylide , is a chemical compound with the formula Cu 2 C 2 . It is a copper (I) salt of acetylene . It consists of Cu + cations and acetylide anions − C≡C − , with the triple bond between the two carbon atoms. Although never characterized by X-ray crystallography , the ... | https://en.wikipedia.org/wiki/Copper(I)_acetylide |
Copper(I) fluoride or cuprous fluoride is an inorganic compound with the chemical formula CuF. Its existence is uncertain. It was reported in 1933 to have a sphalerite -type crystal structure . [ 3 ] Modern textbooks state that CuF is not known, [ 4 ] since fluorine is so electronegative that it will always oxidise cop... | https://en.wikipedia.org/wiki/Copper(I)_fluoride |
Copper(I) iodide is an inorganic compound with the chemical formula Cu I . It is also known as cuprous iodide . It is useful in a variety of applications ranging from organic synthesis to cloud seeding .
Copper(I) iodide is white, but samples often appear tan or, when found in nature as rare mineral marshite , reddish... | https://en.wikipedia.org/wiki/Copper(I)_iodide |
Copper(I) oxide or cuprous oxide is the inorganic compound with the formula Cu 2 O. It is one of the principal oxides of copper , the other being copper(II) oxide or cupric oxide (CuO). The compound can appear either yellow or red, depending on the size of the particles. [ 2 ] Cuprous oxide is found as the mineral cupr... | https://en.wikipedia.org/wiki/Copper(I)_oxide |
Copper phosphide , Cu 3 P , also copper(I) phosphide , cuprous phosphide , cuprophosphorus and phosphor copper , is a compound of copper and phosphorus , a phosphide of copper. It has the appearance of yellowish-grey very brittle mass of crystalline structure. It does not react with water.
Recent crystallographic inve... | https://en.wikipedia.org/wiki/Copper(I)_phosphide |
Copper(I) sulfide is a copper sulfide , a chemical compound of copper and sulfur . It has the chemical compound Cu 2 S. It is found in nature as the mineral chalcocite . It has a narrow range of stoichiometry ranging from Cu 1.997 S to Cu 2.000 S. [ 4 ] Samples are typically black.
Cu 2 S can be prepared by treating c... | https://en.wikipedia.org/wiki/Copper(I)_sulfide |
Copper(I) thiocyanate (or cuprous thiocyanate) is a coordination polymer with formula CuSCN. It is an air-stable, white solid used as a precursor for the preparation of other thiocyanate salts.
At least two polymorphs have been characterized by X-ray crystallography. They both feature copper(I) in a characteristic tet... | https://en.wikipedia.org/wiki/Copper(I)_thiocyanate |
Copper(I) thiophene-2-carboxylate or CuTC is a coordination complex derived from copper and thiophene-2-carboxylic acid . It is used as a reagent to promote the Ullmann reaction between aryl halides . [ 3 ] | https://en.wikipedia.org/wiki/Copper(I)_thiophene-2-carboxylate |
Undetermined (hydrate) [ 2 ]
Copper(II) acetate , also referred to as cupric acetate , is the chemical compound with the formula Cu(OAc) 2 where AcO − is acetate ( CH 3 CO − 2 ). The hydrated derivative, Cu 2 (OAc) 4 (H 2 O) 2 , which contains one molecule of water for each copper atom, is available commercially. Anhy... | https://en.wikipedia.org/wiki/Copper(II)_acetate |
Copper(II) azide is a medium density explosive with the molecular formula Cu ( N 3 ) 2 .
Copper azide is very explosive and is too sensitive for any practical use unless handled in solution .
Copper azide can be prepared by a metathesis reaction between water-soluble sources of Cu 2+ and azide ions. ( Spectator ions ... | https://en.wikipedia.org/wiki/Copper(II)_azide |
Copper(II) borate is an inorganic compound with the formula Cu 3 ( B O 3 ) 2 . It consists of copper atoms in their cupric oxidation state and orthoborate groups. In the 19th century it was proposed to be used as a green pigment to replace the very toxic paris green . [ 3 ] It has been studied for it photocatalytic pro... | https://en.wikipedia.org/wiki/Copper(II)_borate |
Copper(II) glycinate (IUPAC suggested name : bis(glycinato)copper(II)) refers to the coordination complex of copper(II) with two equivalents of glycinate , with the formula [Cu(glycinate) 2 (H 2 O) x ] where x = 1 ( monohydrate ) or 0 ( anhydrous form). The complex was first reported in 1841, and its chemistry has been... | https://en.wikipedia.org/wiki/Copper(II)_glycinate |
Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH) 2 . It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide. Cupric hydroxide is... | https://en.wikipedia.org/wiki/Copper(II)_hydroxide |
Copper(II) nitrate describes any member of the family of inorganic compounds with the formula Cu ( NO 3 ) 2 (H 2 O) x . The hydrates are hygroscopic blue solids . Anhydrous copper nitrate forms blue-green crystals and sublimes in a vacuum at 150-200 °C. [ 5 ] [ 6 ] Common hydrates are the hemipentahydrate and trihydrat... | https://en.wikipedia.org/wiki/Copper(II)_nitrate |
Copper(II) oxalate are inorganic compounds with the chemical formula CuC 2 O 4 (H 2 O) x . The value of x can be 0 and 0.44. One of these species is found as the secondary mineral moolooite (0.44 hydrate). [ 3 ] The anhydrous compound has been characterized by X-ray crystallography . [ 4 ] Many transition metal oxala... | https://en.wikipedia.org/wiki/Copper(II)_oxalate |
Copper(II) oxide or cupric oxide is an inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper , the other being Cu 2 O or copper(I) oxide (cuprous oxide). As a mineral , it is known as tenorite , or sometimes black copper. It is a product of copper mining and the precurs... | https://en.wikipedia.org/wiki/Copper(II)_oxide |
Copper-catalyzed allylic substitutions are chemical reactions with unique regioselectivity compared to other transition-metal-catalyzed allylic substitutions such as the Tsuji-Trost reaction . They involve copper catalysts and "hard" carbon nucleophiles. The mechanism of copper-catalyzed allylic substitutions involves ... | https://en.wikipedia.org/wiki/Copper-catalyzed_allylic_substitution |
Copper-clad steel ( CCS ), also known as copper-covered steel or the trademarked name Copperweld is a bi-metallic product, mainly used in the wire industry that combines the high mechanical strength of steel with the conductivity and corrosion resistance of copper .
It is mainly used for grounding purposes, line traci... | https://en.wikipedia.org/wiki/Copper-clad_steel |
Copper-free click chemistry is a bioorthogonal reaction as a variant of an azide-alkyne Huisgen cycloaddition . By eliminating cytotoxic copper catalysts, the reaction proceeds without live-cell toxicity. [ 1 ] It was developed as a faster alternative to the Staudinger ligation with the first generation of Cu-free clic... | https://en.wikipedia.org/wiki/Copper-free_click_chemistry |
Copper chromite often refers to inorganic compounds with the formula Cu 2 Cr 2 O x . They are black solids. Cu 2 Cr 2 O 4 is a well-defined material. The other copper chromite often is described as Cu 2 Cr 2 O 5 . It is used to catalyze reactions in organic chemistry . [ 3 ]
Copper chromite was first described in 19... | https://en.wikipedia.org/wiki/Copper_chromite |
The copper coulometer is a coulometer consisting of two identical copper electrodes immersed in a slightly acidic pH-buffered solution of copper(II) sulfate ( copper-copper(II) sulfate electrode ). [ 1 ] [ 2 ] Passing of current through the element leads to the anodic dissolution of the metal on anode and simultaneous ... | https://en.wikipedia.org/wiki/Copper_coulometer |
Copper extraction is the multi-stage process of obtaining copper from its ores . The conversion of copper ores consists of a series of physical, chemical, and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations , and other factors. [ 1 ] The... | https://en.wikipedia.org/wiki/Copper_extraction |
Copper has earned a respected place in the related fields of architecture , building construction , and interior design . [ 8 ] From cathedrals to castles and from homes to offices , copper is used for a variety of architectural elements, including roofs , flashings , gutters , downspouts , domes , spires , vaults , wa... | https://en.wikipedia.org/wiki/Copper_in_architecture |
Heat exchangers are devices that transfer heat to achieve desired heating or cooling. An important design aspect of heat exchanger technology is the selection of appropriate materials to conduct and transfer heat fast and efficiently.
Copper has many desirable properties for thermally efficient and durable heat exchan... | https://en.wikipedia.org/wiki/Copper_in_heat_exchangers |
Copper indium gallium (di)selenide ( CIGS ) is a I - III - VI 2 semiconductor material composed of copper , indium , gallium , and selenium . The material is a solid solution of copper indium selenide (often abbreviated "CIS") and copper gallium selenide . It has a chemical formula of CuIn 1− x Ga x Se 2 , where the va... | https://en.wikipedia.org/wiki/Copper_indium_gallium_selenide |
Copper loss is the term often given to heat produced by electrical currents in the conductors of transformer windings, or other electrical devices. Copper losses are an undesirable transfer of energy , as are core losses , which result from induced currents in adjacent components. The term is applied regardless of whet... | https://en.wikipedia.org/wiki/Copper_loss |
West Asia (6000–3500 BC)
Europe (5500–2200 BC)
Central Asia (3700–1700 BC)
South Asia (4300–1800 BC)
China (5000–2900 BC)
Copper metallurgy in Africa encompasses the study of copper production across the continent and an understanding of how it influenced aspects of African archaeology .
Scholars previously belie... | https://en.wikipedia.org/wiki/Copper_metallurgy_in_Africa |
Copper sweetening is a petroleum refining process using a slurry of clay and cupric chloride to oxidize mercaptans . The resulting disulfides are less odorous and usually very viscous, and are usually removed from the lower-boiling fractions and left in the heavy fuel oil fraction. [ 1 ] [ 2 ]
Copper sweetening introd... | https://en.wikipedia.org/wiki/Copper_sweetening |
Copper zinc antimony sulfide is a semiconductor . [ 1 ]
This electronics-related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Copper_zinc_antimony_sulfide |
Copper zinc water filtration is a high-purity brass water filtration process that relies on the redox potential of dissolved oxygen in water in the presence of a zinc anode and copper cathode . It uses dissolved impurities within water as constituent substrate, which are reduced to more physiologically inert compounds.... | https://en.wikipedia.org/wiki/Copper_zinc_water_filtration |
Copperas works are manufactories where copperas ( iron(II) sulfate ) is produced from pyrite , often obtained as a byproduct during coal mining , and iron. The history of producing green vitriol, as it was known, goes back hundreds of years in Scotland. [ 1 ] In 1814 the wool-producing city of Steubenville , Ohio had s... | https://en.wikipedia.org/wiki/Copperas_works |
The copper – chlorine cycle (Cu–Cl cycle) is a four-step thermochemical cycle for the production of hydrogen. The Cu–Cl cycle is a hybrid process that employs both thermochemical and electrolysis steps.
It has a maximum temperature requirement of about 530 degrees Celsius. [ 1 ]
The Cu–Cl cycle involves four chemical ... | https://en.wikipedia.org/wiki/Copper–chlorine_cycle |
In chemistry , coprecipitation ( CPT ) or co-precipitation is the carrying down by a precipitate of substances normally soluble under the conditions employed. [ 1 ] Analogously, in medicine , coprecipitation (referred to as immunoprecipitation ) is specifically "an assay designed to purify a single antigen from a compl... | https://en.wikipedia.org/wiki/Coprecipitation |
Coprinol is an antibiotic isolated from Coprinus . [ 1 ]
This organic chemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Coprinol |
Coprophagia ( / ˌ k ɒ p r ə ˈ f eɪ dʒ i ə / KOP -rə- FAY -jee-ə ) [ 1 ] or coprophagy ( / k ə ˈ p r ɒ f ə dʒ i / kə- PROF -ə-jee ) is the consumption of feces . The word is derived from the Ancient Greek κόπρος kópros "feces" and φαγεῖν phageîn "to eat". Coprophagy refers to many kinds of feces-eating, including eating... | https://en.wikipedia.org/wiki/Coprophagia |
Coprophobia is fear of or aversion to feces or defecation . [ 1 ]
In humans, the attitude to feces and defecation has become a cultural taboo . [ 2 ]
In the animal world, many herbivorous grazing animals including cows, sheep, horses, and reindeer avoid feces when feeding. Primates also prefer to forage away from fe... | https://en.wikipedia.org/wiki/Coprophobia |
Coproporphyrinogens are tetrapyrroles with four propionic acid groups and an equal number of substituted methyls .
Coproporphyrinogen III is the most common variance. In the metabolism of porphyrin , it is formed from uroporphyrinogen III by the enzyme uroporphyrinogen III decarboxylase , and it is converted into prot... | https://en.wikipedia.org/wiki/Coproporphyrinogens |
5β-Coprostanol ( 5β-cholestan-3β-ol ) is a 27- carbon stanol formed from the net reductive metabolism of cholesterol (cholest-5en-3β-ol) in the gut of most higher animals and birds. This compound has frequently been used as a biomarker for the presence of human faecal matter in the environment . 5β-coprostanol is thoug... | https://en.wikipedia.org/wiki/Coprostanol |
The copula linguae or copula , is a swelling that forms from the second pharyngeal arch , late in the fourth week of embryogenesis . [ 1 ] During the fifth and sixth weeks the copula becomes overgrown and covered by the hypopharyngeal eminence which forms mostly from the third pharyngeal arch and in part from the fourt... | https://en.wikipedia.org/wiki/Copula_linguae |
Copurification in a chemical or biochemical context is the physical separation by chromatography or other purification technique of two or more substances of interest from other contaminating substances. For substances to co-purify usually implies that these substances attract each other to form a non-covalent complex ... | https://en.wikipedia.org/wiki/Copurification |
The copy attack is an attack on certain digital watermarking systems proposed by M. Kutter, S. Voloshynovskiy, and A. Herrige in a paper presented in January, 2000 at the Photonics West SPIE convention. [ 1 ]
In some scenarios, a digital watermark is added to a piece of media such as an image , film , or audio clip , ... | https://en.wikipedia.org/wiki/Copy_attack |
Copy number analysis is the process of analyzing data produced by a test for DNA copy number variation in an organism's sample. One application of such analysis is the detection of chromosomal copy number variation that may cause or may increase risks of various critical disorders. [ 1 ] [ 2 ] Copy number variation can... | https://en.wikipedia.org/wiki/Copy_number_analysis |
Copy number variation ( CNV ) is a phenomenon in which sections of the genome are repeated and the number of repeats in the genome varies between individuals. [ 1 ] Copy number variation is a type of structural variation : specifically, it is a type of duplication or deletion event that affects a considerable number of... | https://en.wikipedia.org/wiki/Copy_number_variation |
In the study of scale-free networks , a copying mechanism is a process by which such a network can form and grow, by means of repeated steps in which nodes are duplicated with mutations from existing nodes. Several variations have been studied. In the general copying model , a growing network starts as a small initial ... | https://en.wikipedia.org/wiki/Copying_mechanism |
Copying network models are network generation models that use a copying mechanism to form a network, by repeatedly duplicating and mutating existing nodes of the network. Such a network model has first been proposed in 1999 to explain the network of links between web pages, but since has been used to model biological a... | https://en.wikipedia.org/wiki/Copying_network_models |
María del Coral Barbas Arribas (or Arriba ) is a professor at the Universidad CEU San Pablo in Madrid, Spain who is known for her research on metabolomics and integration of chemical data. [ clarification needed ]
Barbas has a Ph.D. from Complutense University of Madrid . [ 1 ] From 2005 until 2006 she was a Marie Cur... | https://en.wikipedia.org/wiki/Coral_Barbas |
Coral calcium is a salt of calcium derived from fossilized coral reefs (primarily from limestone and coastal deposits). It has been promoted as an alternative, but unsubstantiated, treatment or cure for a number of health conditions.
Coral calcium is a salt of calcium derived from fossilized coral reefs. Coral calcium... | https://en.wikipedia.org/wiki/Coral_calcium |
The coral of life is a metaphor or a mathematical model useful to illustrate evolution of life or phylogeny at various levels of resolution, including individual organisms , populations, species and large taxonomic groups. Its use in biology resolves several practical and conceptual difficulties that are associated wit... | https://en.wikipedia.org/wiki/Coral_of_life |
Corals of the World Online , or simply Corals of the World , is an open access website aiming to become a fully comprehensive and up-to-date reference on the subjects of coral taxonomy , biogeography and identification. It is focused only on the group of zooxanthellate Scleractinia , also called stony corals, the order... | https://en.wikipedia.org/wiki/Corals_of_the_World_(website) |
In mathematics , corank is complementary to the concept of the rank of a mathematical object, and may refer to the dimension of the left nullspace of a matrix , the dimension of the cokernel of a linear transformation of a vector space , or the number of elements of a matroid minus its rank . [ 1 ]
The corank of an m ... | https://en.wikipedia.org/wiki/Corank |
Cordwood construction (also called cordwood masonry or cordwood building , alternatively stackwall or stovewood particularly in Canada) is a term used for a natural building method in which short logs are piled crosswise to build a wall, using mortar or cob to permanently secure them. This technique can be made to use ... | https://en.wikipedia.org/wiki/Cordwood_construction |
Core-and-veneer , brick and rubble , wall and rubble , ashlar and rubble , and emplekton all refer to a building technique where two parallel walls are constructed and the core between them is filled with rubble or other infill, creating one thick wall. [ 1 ] Originally, and in later poorly constructed walls, the rubbl... | https://en.wikipedia.org/wiki/Core-and-veneer |
In general topology and related branches of mathematics , a core-compact topological space X {\displaystyle X} is a topological space whose partially ordered set of open subsets is a continuous poset . [ 1 ] Equivalently, X {\displaystyle X} is core-compact if it is exponentiable in the category Top of topological spac... | https://en.wikipedia.org/wiki/Core-compact_space |
A core-excited shape resonance is a shape resonance in a system with more than one degree of freedom where, after fragmentation, one of the fragments is in an excited state. It is sometimes very difficult to distinguish a core-excited shape resonance from a Feshbach resonance .
See the definition of Feshbach resonance... | https://en.wikipedia.org/wiki/Core-excited_shape_resonance |
CoreAVC was a proprietary codec for decoding the H.264/MPEG-4 AVC (Advanced Video Coding) video format.
In 2010, when CoreAVC was a software-only decoder, it was one of the fastest software decoders, but still slower than hardware-based ones. [ 2 ] CoreAVC supports all H.264 Profiles except for 4:2:2 and 4:4:4.
From ... | https://en.wikipedia.org/wiki/CoreAVC |
The Core Audio Format is a container format for storing audio, developed by Apple Inc. It is compatible with Mac OS X 10.4 and higher; Mac OS X 10.3 needs QuickTime 7 to be installed. [ 1 ]
Core Audio Format is designed to overcome limitations of older digital audio formats, including AIFF and WAV . Just like the Quic... | https://en.wikipedia.org/wiki/Core_Audio_Format |
Core War is a programming game introduced in 1984 by D. G. Jones and A. K. Dewdney . In the game, two or more battle programs, known as warriors , compete for control of a virtual computer . These programs are written in an abstract assembly language called Redcode . Initial standards for Redcode and the virtual machin... | https://en.wikipedia.org/wiki/Core_War |
Core electrons are the electrons in an atom that are not valence electrons and do not participate as directly in chemical bonding . [ 1 ] The nucleus and the core electrons of an atom form the atomic core. Core electrons are tightly bound to the nucleus. Therefore, unlike valence electrons, core electrons play a second... | https://en.wikipedia.org/wiki/Core_charge |
Core damage frequency ( CDF ) is a term used in probabilistic risk assessment (PRA) that indicates the likelihood of an accident that would cause severe damage to a nuclear fuel in a nuclear reactor core . [ 1 ] [ 2 ] [ 3 ] Core damage accidents are considered extremely serious because severe damage to the fuel in the ... | https://en.wikipedia.org/wiki/Core_damage_frequency |
Core electrons are the electrons in an atom that are not valence electrons and do not participate as directly in chemical bonding . [ 1 ] The nucleus and the core electrons of an atom form the atomic core. Core electrons are tightly bound to the nucleus. Therefore, unlike valence electrons, core electrons play a second... | https://en.wikipedia.org/wiki/Core_electron |
A core sample is a cylindrical section of (usually) a naturally-occurring substance. Most core samples are obtained by drilling with special drills into the substance, such as sediment or rock, with a hollow steel tube, called a core drill . The hole made for the core sample is called the "core hole". A variety of core... | https://en.wikipedia.org/wiki/Core_sample |
In quantum mechanics, symmetry operations are of importance in giving information about solutions to a system. Typically these operations form a mathematical group , such as the rotation group SO(3) for spherically symmetric potentials. The representation theory of these groups leads to irreducible representations , wh... | https://en.wikipedia.org/wiki/Corepresentations_of_unitary_and_antiunitary_groups |
In genetics and molecular biology , a corepressor is a molecule that represses the expression of genes . [ 1 ] In prokaryotes , corepressors are small molecules whereas in eukaryotes , corepressors are proteins . A corepressor does not directly bind to DNA , but instead indirectly regulates gene expression by binding t... | https://en.wikipedia.org/wiki/Corepressor |
COREU (French: Correspondance Européenne – Telex network of European correspondents, also EUKOR-Netzwerk in Austria [ 1 ] ) is a communication network of the European Union for the communication of the Council of the European Union , the European correspondents of the foreign ministries of the EU member states , perman... | https://en.wikipedia.org/wiki/Coreu |
The Corey–Fuchs reaction , also known as the Ramirez–Corey–Fuchs reaction , is a series of chemical reactions designed to transform an aldehyde into an alkyne . [1] [2] [3] The formation of the 1,1-dibromoolefins via phosphine-dibromomethylenes was originally discovered by Desai, McKelvie and Ramirez. [4] The phosphine... | https://en.wikipedia.org/wiki/Corey–Fuchs_reaction |
The Corey–House synthesis (also called the Corey–Posner–Whitesides–House reaction and other permutations) is an organic reaction that involves the reaction of a lithium diorganylcuprate ( R 2 CuLi {\displaystyle {\ce {R_{2}CuLi}}} ) with an organic halide or pseudohalide ( R ′ − X {\displaystyle {\ce {R'-X}}} ) to form... | https://en.wikipedia.org/wiki/Corey–House_synthesis |
The Corey–Itsuno reduction , also known as the Corey–Bakshi–Shibata (CBS) reduction , is a chemical reaction in which a prochiral ketone is enantioselectively reduced to produce the corresponding chiral , non-racemic alcohol. The oxazaborolidine reagent which mediates the enantioselective reduction of ketones was previ... | https://en.wikipedia.org/wiki/Corey–Itsuno_reduction |
The Corey–Kim oxidation is an oxidation reaction used to synthesize aldehydes and ketones from primary and secondary alcohols . [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] It is named for American chemist and Nobel Laureate Elias James Corey and Korean-American chemist Choung Un Kim .
Although the Corey–Kim oxidation possesses the ... | https://en.wikipedia.org/wiki/Corey–Kim_oxidation |
In organic chemistry , the Corey–Link reaction is a name reaction that converts a 1,1,1-trichloro-2-keto structure into a 2-aminocarboxylic acid (an alpha amino acid ) or other acyl functional group with control of the chirality at the alpha position . The reaction is named for E.J. Corey and John Link, who first repor... | https://en.wikipedia.org/wiki/Corey–Link_reaction |
Corey–Nicolaou macrolactonization is a named reaction of organic chemistry , for the synthesis of lactones from hydroxy acids , found in 1974. [ 1 ] [ 2 ] The reaction uses 2,2'-dipyridyldisulfide and triphenylphosphine as reagents and runs in polar aprotic solvent under mild conditions. [ 3 ]
The hydroxy acid first r... | https://en.wikipedia.org/wiki/Corey–Nicolaou_macrolactonization |
In biochemistry , the Corey–Pauling rules are a set of three basic statements that govern the secondary nature of proteins, in particular, the CO-NH peptide link. They were originally proposed by Robert Corey and Linus Pauling . [ 1 ]
The rules are as follows:
This stereochemistry article is a stub . You can help Wik... | https://en.wikipedia.org/wiki/Corey–Pauling_rules |
The Corey–Seebach reaction , or Seebach Umpolung is a name reaction of organic chemistry that allows for acylation by converting aldehydes into lithiated 1,3-dithianes . The lithiated 1,3-dithianes serves as an acyl anion equivalent, undergoing alkylation with electrophiles . [ 1 ] The reaction is named in honor of its... | https://en.wikipedia.org/wiki/Corey–Seebach_reaction |
The Corey–Winter olefin synthesis (also known as Corey–Winter–Eastwood olefination ) is a series of chemical reactions for converting 1,2- diols into olefins . [ 1 ] [ 2 ] [ 3 ] [ 4 ] It is named for the American chemist and Nobelist Elias James Corey and the American-Estonian chemist Roland Arthur Edwin Winter . [ 5 ]... | https://en.wikipedia.org/wiki/Corey–Winter_olefin_synthesis |
A corf (pl. corves) also spelt corve (pl. corves) in mining is a wicker basket or a small human powered (in later times in the case of the larger mines, horse drawn) minecart for carrying or transporting coal, ore, etc. [ 1 ] Human powered corfs had generally been phased out by the turn of the 20th century, with horse... | https://en.wikipedia.org/wiki/Corf_(mining) |
The Cori cycle (also known as the lactic acid cycle ), named after its discoverers, Carl Ferdinand Cori and Gerty Cori , [ 1 ] is a metabolic pathway in which lactate , produced by anaerobic glycolysis in muscles, is transported to the liver and converted to glucose, which then returns to the muscles and is cyclically ... | https://en.wikipedia.org/wiki/Cori_cycle |
Coring happens when a heated alloy, such as a Cu-Ni system, cools in non-equilibrium conditions. The center of each grain, which is the first part to freeze, is rich in the high-melting element (e.g., nickel for this Cu–Ni system), whereas the concentration of the low-melting element increases with position from this r... | https://en.wikipedia.org/wiki/Coring |
Corinthian bronze , also named Corinthian brass, aes Corinthiacum, or Grilver was a metal alloy in classical antiquity . It is thought to be an alloy of copper with gold or silver (or both), although it has also been contended that it was simply a very high grade of bronze , or a kind of bronze that was manufactured i... | https://en.wikipedia.org/wiki/Corinthian_bronze |
In physics , the Coriolis force is a fictitious force that acts on objects in motion within a frame of reference that rotates with respect to an inertial frame . In a reference frame with clockwise rotation, the force acts to the left of the motion of the object. In one with anticlockwise (or counterclockwise) rotation... | https://en.wikipedia.org/wiki/Coriolis_force |
In fluid dynamics , the Coriolis–Stokes force is a forcing of the mean flow in a rotating fluid due to interaction of the Coriolis effect and wave-induced Stokes drift . This force acts on water independently of the wind stress . [ 1 ]
This force is named after Gaspard-Gustave Coriolis and George Gabriel Stokes , two ... | https://en.wikipedia.org/wiki/Coriolis–Stokes_force |
Corium , also called fuel-containing material ( FCM ) or lava-like fuel-containing material ( LFCM ), is a material that is created in a nuclear reactor core during a nuclear meltdown accident. Resembling lava in consistency, it consists of a mixture of nuclear fuel , fission products , control rods , structural materi... | https://en.wikipedia.org/wiki/Corium_(nuclear_reactor) |
Cormophytes ( Cormophyta ) is a historical term seldom used today for the plants that are differentiated into roots, stems and leaves . These plants differ from thallophytes , whose body is referred to as the thallus , i.e. a simple body not differentiated into leaves and stems. Definitions have varied, notably about w... | https://en.wikipedia.org/wiki/Cormophyte |
Cormus ( PL : cormi ) (from ancient Greek : κορμός, kormόs, 'stem') is the appearance of a plant that belong to Cormophyte ( Pteridophyte and Spermatophyte ). [ 1 ] [ 2 ] In cormus, the vegetative apparatus is no longer a thallus , such as algae , that cannot be distinctly differentiated. [ 1 ] The structure of cormus ... | https://en.wikipedia.org/wiki/Cormus |
In geometry , a corner-point grid is a tessellation of a Euclidean 3D volume, where the base cell has 6 faces ( hexahedron ).
A set of straight lines defined by their end points define the pillars of the corner-point grid. The pillars have a lexicographical ordering that determines neighbouring pillars. On each pillar... | https://en.wikipedia.org/wiki/Corner-point_grid |
In statistical mechanics , the corner transfer matrix describes the effect of adding a quadrant to a lattice. Introduced by Rodney Baxter in 1968 as an extension of the Kramers-Wannier row-to-row transfer matrix, it provides a powerful method of studying lattice models . Calculations with corner transfer matrices led B... | https://en.wikipedia.org/wiki/Corner_transfer_matrix |
The Cornforth reagent ( pyridinium dichromate or PDC ) is a pyridinium salt of dichromate with the chemical formula [C 5 H 5 NH] 2 [Cr 2 O 7 ]. This compound is named after the Australian-British chemist Sir John Warcup Cornforth (b. 1917) who introduced it in 1962. [ 2 ] [ 3 ] The Cornforth reagent is a strong oxidizi... | https://en.wikipedia.org/wiki/Cornforth_reagent |
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