text stringlengths 11 320k | source stringlengths 26 161 |
|---|---|
In the mathematical theory of conformal mappings , the area theorem gives an inequality satisfied by
the power series coefficients of certain conformal mappings.
The theorem is called by that name, not because of its implications, but rather because the proof uses
the notion of area .
Suppose that f {\displaystyle f} ... | https://en.wikipedia.org/wiki/Area_theorem_(conformal_mapping) |
Arena BioWorks is a recently-announced biomedical institute that will be located in Kendall Square in Cambridge, Massachusetts . Having attracted notable scientists, the institute is led by Stuart Schreiber . [ 1 ]
The institute has $500 million in initial private funding backed by individuals including Steve Pagliuca... | https://en.wikipedia.org/wiki/Arena_BioWorks |
Arene substitution patterns are part of organic chemistry IUPAC nomenclature and pinpoint the position of substituents other than hydrogen in relation to each other on an aromatic hydrocarbon .
The toluidines serve as an example for these three types of substitution.
Electron donating groups, for example amino , hydr... | https://en.wikipedia.org/wiki/Arene_substitution_pattern |
The Arens–van Dorp synthesis is a name reaction in organic chemistry . [ 1 ] It describes the addition of lithiated ethoxyacetylenes to ketones to give propargyl alcohols, which can undergo further reaction to form α,β-unsaturated aldehydes , [ 2 ] or esters. [ 3 ] There is also a variation of this reaction called the ... | https://en.wikipedia.org/wiki/Arens–van_Dorp_synthesis |
Arformoterol , sold under the brand name Brovana among others, is a medication used for the treatment of chronic obstructive pulmonary disease (COPD). [ 1 ] [ 2 ]
It is a long-acting β 2 adrenoreceptor agonist (LABA) and it is the active ( R , R )-(−)- enantiomer of formoterol . [ 1 ] It was approved for medical use i... | https://en.wikipedia.org/wiki/Arformoterol |
In mathematics , the arguments of the maxima (abbreviated arg max or argmax ) and arguments of the minima (abbreviated arg min or argmin ) are the input points at which a function output value is maximized and minimized , respectively. [ note 1 ] While the arguments are defined over the domain of a function , the outpu... | https://en.wikipedia.org/wiki/Arg_max |
Argentation chromatography is chromatography using a stationary phase that contains silver salts. Silver-containing stationary phases are well suited for separating organic compounds on the basis of the number and type of alkene groups. The technique is employed for gas chromatography and various types of liquid chroma... | https://en.wikipedia.org/wiki/Argentation_chromatography |
In analytical chemistry , argentometry is a type of titration involving the silver (I) ion. Typically, it is used to determine the amount of chloride present in a sample. The sample solution is titrated against a solution of silver nitrate of known concentration. Chloride ions react with silver(I) ions to give the inso... | https://en.wikipedia.org/wiki/Argentometry |
The arginine catabolic mobile element (ACME) is a mobile genetic element of Staphylococcus bacterial species. This genetic element provides for several immune modulating functions, including resistance to polyamines which serve as a non-specific immune response both on intact skin and following the inflammatory respon... | https://en.wikipedia.org/wiki/Arginine_catabolic_mobile_element |
In molecular biology , an arginine finger is an amino acid residue of some enzymes . [ 1 ] [ 2 ] Arginine fingers are often found in the protein superfamily of AAA+ ATPases , GTPases , and dUTPases , where they assist in the catalysis of the gamma phosphate or gamma and beta phosphates from ATP or GTP , which creates a... | https://en.wikipedia.org/wiki/Arginine_finger |
Arginylation is a post-translational modification in which proteins are modified by the addition of arginine (Arg) at the N-terminal amino group or side chains of reactive amino acids by the enzyme, arginyltransferase (ATE1) . Recent studies have also revealed that hundreds of proteins in vivo are arginylated, proteins... | https://en.wikipedia.org/wiki/Arginylation |
Argon fluorohydride (systematically named fluoridohydridoargon ) or argon hydrofluoride is an inorganic compound with the chemical formula HArF (also written ArHF). It is a compound of the chemical element argon .
The discovery of this argon compound is credited to a group of Finnish scientists, led by Markku Räsänen.... | https://en.wikipedia.org/wiki/Argon_fluorohydride |
The Argonaute protein family, first discovered for its evolutionarily conserved stem cell function, [ 1 ] plays a central role in RNA silencing processes as essential components of the RNA-induced silencing complex (RISC). RISC is responsible for the gene silencing phenomenon known as RNA interference (RNAi) . [ 2 ] Ar... | https://en.wikipedia.org/wiki/Argonaute |
The Argonne–Northwestern Solar Energy Research Center ( ANSER Center ) is a joint research program between the Argonne National Laboratory and Northwestern University . Michael R. Wasielewski , Professor of Chemistry at Northwestern founded the ANSER center in 2007 and is its current director. The center's goal is to ... | https://en.wikipedia.org/wiki/Argonne–Northwestern_Solar_Energy_Research_Center |
An argument is a series of sentences , statements , or propositions some of which are called premises and one is the conclusion . [ 1 ] The purpose of an argument is to give reasons for one's conclusion via justification, explanation , and/or persuasion .
Arguments are intended to determine or show the degree of truth... | https://en.wikipedia.org/wiki/Argument |
In mathematics (particularly in complex analysis ), the argument of a complex number z , denoted arg( z ) , is the angle between the positive real axis and the line joining the origin and z , represented as a point in the complex plane , shown as φ {\displaystyle \varphi } in Figure 1. By convention the positive real a... | https://en.wikipedia.org/wiki/Argument_(complex_analysis) |
Argument from analogy is a special type of inductive argument , where perceived similarities are used as a basis to infer some further similarity that has not been observed yet. Analogical reasoning is one of the most common methods by which human beings try to understand the world and make decisions. [ 1 ] When a per... | https://en.wikipedia.org/wiki/Argument_from_analogy |
Originating in the legal profession , argument in the alternative is a strategy in which a lawyer advances several competing (and possibly mutually exclusive ) arguments in order to pre-empt objections by his adversary, with the goal of showing that regardless of interpretation there is no reasonable conclusion other t... | https://en.wikipedia.org/wiki/Argument_in_the_alternative |
In mathematics , an argument of a function is a value provided to obtain the function's result. It is also called an independent variable . [ 1 ]
For example, the binary function f ( x , y ) = x 2 + y 2 {\displaystyle f(x,y)=x^{2}+y^{2}} has two arguments, x {\displaystyle x} and y {\displaystyle y} , in an ordered pa... | https://en.wikipedia.org/wiki/Argument_of_a_function |
In celestial mechanics , the argument of latitude ( u {\displaystyle u} ) is an angular parameter that defines the position of a body moving along a Kepler orbit . It is the angle between the ascending node and the body.
It is the sum of the more commonly used true anomaly and argument of periapsis .
u = ν + ω {\disp... | https://en.wikipedia.org/wiki/Argument_of_latitude |
The argument of periapsis (also called argument of perifocus or argument of pericenter ), symbolized as ω ( omega ) , is one of the orbital elements of an orbiting body. Parametrically, ω is the angle from the body's ascending node to its periapsis , measured in the direction of motion.
For specific types of orbits, ... | https://en.wikipedia.org/wiki/Argument_of_periapsis |
In artificial intelligence and related fields, an argumentation framework is a way to deal with contentious information and draw conclusions from it using formalized arguments .
In an abstract argumentation framework, [ 1 ] entry-level information is a set of abstract arguments that, for instance, represent data or a ... | https://en.wikipedia.org/wiki/Argumentation_framework |
Argumentation theory is the interdisciplinary study of how conclusions can be supported or undermined by premises through logical reasoning . With historical origins in logic , dialectic , and rhetoric , argumentation theory includes the arts and sciences of civil debate, dialogue , conversation , and persuasion . It s... | https://en.wikipedia.org/wiki/Argumentation_theory |
In logic , an argumentum e contrario (Latin: 'argument from the contrary'; also a contrario or ex contrario [ 1 ] ), also known as appeal from the contrary , denotes any proposition that is argued to be correct because it is not disproven by a certain case. It is the opposite of the analogy . When analogy is allowed, e... | https://en.wikipedia.org/wiki/Argumentum_e_contrario |
Argument–deduction–proof distinctions originated with logic itself. [ 1 ] Naturally, the terminology evolved.
An argument , more fully a premise–conclusion argument, is a two-part system composed of premises and conclusion. An argument is valid if and only if its conclusion is a consequence of its premises. Every prem... | https://en.wikipedia.org/wiki/Argument–deduction–proof_distinctions |
Argus retinal prosthesis , also known as a bionic eye , is an electronic retinal implant manufactured by the American company Second Sight Medical Products. It is used as a visual prosthesis to improve the vision of people with severe cases of retinitis pigmentosa . The Argus II version of the system was approved for m... | https://en.wikipedia.org/wiki/Argus_retinal_prosthesis |
Argus – the Audit Record Generation and Utilization System is the first implementation of network flow monitoring, and is an ongoing open source network flow monitor project. Started by Carter Bullard in 1984 at Georgia Tech, and developed for cyber security at Carnegie Mellon University in the early 1990s, Argus has ... | https://en.wikipedia.org/wiki/Argus_–_Audit_Record_Generation_and_Utilization_System |
Ariane Next [ 2 ] —partially reusable launcher is planned to succeed Ariane 6 , with an entry into service in the 2030s. The objective of the new launcher is to halve the launch costs compared with Ariane 6. Funded by the EU under the Horizon Europe programme, project SALTO (reusable strategic space launcher technologi... | https://en.wikipedia.org/wiki/Ariane_Next |
An aridity index (AI) is a numerical indicator of the degree of dryness of the climate at a given location. The American Meteorological Society defined it in meteorology and climatology, as "the degree to which a climate lacks effective, life-promoting moisture". Aridity is different from drought because aridity is per... | https://en.wikipedia.org/wiki/Aridity_index |
Arieh Warshel ( Hebrew : אריה ורשל ; born November 20, 1940) is an Israeli-American biochemist and biophysicist . He is a pioneer in computational studies on functional properties of biological molecules , Distinguished Professor of Chemistry and Biochemistry, and holds the Dana and David Dornsife Chair in Chemistry at... | https://en.wikipedia.org/wiki/Arieh_Warshel |
Ariel 5 (or UK 5) was a joint British and American space telescope dedicated to observing the sky in the X-ray band. It was launched on 15 October 1974 from the San Marco platform in the Indian Ocean and operated until 1980. It was the penultimate satellite to be launched as part of the Ariel programme .
Ariel 5 was t... | https://en.wikipedia.org/wiki/Ariel_5 |
Aristarchus's inequality (after the Greek astronomer and mathematician Aristarchus of Samos ; c. 310 – c. 230 BCE) is a law of trigonometry which states that if α and β are acute angles (i.e. between 0 and a right angle) and β < α then
Ptolemy used the first of these inequalities while constructing his table of chords... | https://en.wikipedia.org/wiki/Aristarchus's_inequality |
Aristid von Grosse (January 1905 – July 21, 1985) was a German nuclear chemist . During his work with Otto Hahn , he got access to waste material from radium production, and with this starting material he was able in 1927 to isolate protactinium(V) oxide [ 1 ] and was later able to produce metallic protactinium [ 2 ] [... | https://en.wikipedia.org/wiki/Aristid_von_Grosse |
In the philosophy of mathematics , Aristotelian realism holds that mathematics studies properties such as symmetry , continuity and order that can be immanently realized in the physical world (or in any other world there might be). It contrasts with Platonism in holding that the objects of mathematics, such as numbers,... | https://en.wikipedia.org/wiki/Aristotelian_realist_philosophy_of_mathematics |
Arithmetic Fuchsian groups are a special class of Fuchsian groups constructed using orders in quaternion algebras . They are particular instances of arithmetic groups . The prototypical example of an arithmetic Fuchsian group is the modular group P S L 2 ( Z ) {\displaystyle \mathrm {PSL} _{2}(\mathbb {Z} )} . They, an... | https://en.wikipedia.org/wiki/Arithmetic_Fuchsian_group |
In mathematics , the Frobenius endomorphism is defined in any commutative ring R that has characteristic p , where p is a prime number . Namely, the mapping φ that takes r in R to r p is a ring endomorphism of R .
The image of φ is then R p , the subring of R consisting of p -th powers. In some important cases, for ex... | https://en.wikipedia.org/wiki/Arithmetic_and_geometric_Frobenius |
In recreational mathematics , arithmetic billiards provide a geometrical method to determine the least common multiple (LCM) and the greatest common divisor (GCD) of two natural numbers . It makes use of reflections inside a rectangle that has sides with length of the two given numbers. This is a simple example of traj... | https://en.wikipedia.org/wiki/Arithmetic_billiards |
Arithmetic coding ( AC ) is a form of entropy encoding used in lossless data compression . Normally, a string of characters is represented using a fixed number of bits per character, as in the ASCII code. When a string is converted to arithmetic encoding, frequently used characters will be stored with fewer bits and no... | https://en.wikipedia.org/wiki/Arithmetic_coding |
Arithmetic for Parents (Sumizdat, 2007, ISBN 9780977985258 ) is a book about mathematics education aimed at parents and teachers. [ 1 ] [ 2 ]
The author, Ron Aharoni , is a professor of mathematics at the Technion ; he wrote the book based on his experiences teaching elementary mathematics to Israeli schoolchildren. ... | https://en.wikipedia.org/wiki/Arithmetic_for_Parents |
In mathematics , an arithmetic group is a group obtained as the integer points of an algebraic group , for example S L 2 ( Z ) . {\displaystyle \mathrm {SL} _{2}(\mathbb {Z} ).} They arise naturally in the study of arithmetic properties of quadratic forms and other classical topics in number theory . They also give ris... | https://en.wikipedia.org/wiki/Arithmetic_group |
In mathematics , more precisely in group theory and hyperbolic geometry , Arithmetic Kleinian groups are a special class of Kleinian groups constructed using orders in quaternion algebras . They are particular instances of arithmetic groups . An arithmetic hyperbolic three-manifold is the quotient of hyperbolic space H... | https://en.wikipedia.org/wiki/Arithmetic_hyperbolic_3-manifold |
In computing , an arithmetic logic unit ( ALU ) is a combinational digital circuit that performs arithmetic and bitwise operations on integer binary numbers . [ 1 ] [ 2 ] This is in contrast to a floating-point unit (FPU), which operates on floating point numbers. It is a fundamental building block of many types of com... | https://en.wikipedia.org/wiki/Arithmetic_logic_unit |
In computer programming , an integer overflow occurs when an arithmetic operation on integers attempts to create a numeric value that is outside of the range that can be represented with a given number of digits – either higher than the maximum or lower than the minimum representable value.
The most common result of a... | https://en.wikipedia.org/wiki/Arithmetic_overflow |
An arithmetic progression or arithmetic sequence is a sequence of numbers such that the difference from any succeeding term to its preceding term remains constant throughout the sequence. The constant difference is called common difference of that arithmetic progression. For instance, the sequence 5, 7, 9, 11, 13, 15, ... | https://en.wikipedia.org/wiki/Arithmetic_progression |
In computer programming , an arithmetic shift is a shift operator , sometimes termed a signed shift (though it is not restricted to signed operands). The two basic types are the arithmetic left shift and the arithmetic right shift . For binary numbers it is a bitwise operation that shifts all of the bits of its operan... | https://en.wikipedia.org/wiki/Arithmetic_shift |
The term arithmetic underflow (also floating-point underflow , or just underflow ) is a condition in a computer program where the result of a calculation is a number of more precise absolute value than the computer can actually represent in memory on its central processing unit (CPU).
Arithmetic underflow can occur wh... | https://en.wikipedia.org/wiki/Arithmetic_underflow |
In mathematics , the arithmetic zeta function is a zeta function associated with a scheme of finite type over integers . The arithmetic zeta function generalizes the Riemann zeta function and Dedekind zeta function to higher dimensions. The arithmetic zeta function is one of the most-fundamental objects of number theor... | https://en.wikipedia.org/wiki/Arithmetic_zeta_function |
Diophantus of Alexandria ( Ancient Greek : Διόφαντος , romanized : Diophantos ) ( / d aɪ oʊ ˈ f æ n t ə s / ; fl. 250 CE ) was a Greek mathematician who was the author of the Arithmetica in thirteen books, ten of which are still extant, made up of arithmetical problems that are solved through algebraic equations .
Alt... | https://en.wikipedia.org/wiki/Arithmetica |
Henry Briggs (1 February 1561 – 26 January 1630) was an English mathematician notable for changing the original logarithms invented by John Napier into common (base 10) logarithms , which are sometimes known as Briggsian logarithms in his honor. The specific algorithm for long division in modern use was introduced by B... | https://en.wikipedia.org/wiki/Arithmetica_Logarithmica |
The 1889 treatise Arithmetices principia, nova methodo exposita ( The principles of arithmetic, presented by a new method ) by Giuseppe Peano is widely considered to be a seminal document in mathematical logic and set theory , [ 1 ] [ 2 ] introducing what is now the standard axiomatization of the natural numbers , and ... | https://en.wikipedia.org/wiki/Arithmetices_principia,_nova_methodo_exposita |
In mathematics , an arithmetico-geometric sequence is the result of element-by-element multiplication of the elements of a geometric progression with the corresponding elements of an arithmetic progression . The n th element of an arithmetico-geometric sequence is the product of the n th element of an arithmetic sequen... | https://en.wikipedia.org/wiki/Arithmetico-geometric_sequence |
In mathematics , the arithmetic–geometric mean (AGM or agM [ 1 ] ) of two positive real numbers x and y is the mutual limit of a sequence of arithmetic means and a sequence of geometric means . The arithmetic–geometric mean is used in fast algorithms for exponential , trigonometric functions , and other special functio... | https://en.wikipedia.org/wiki/Arithmetic–geometric_mean |
The arithmetization of analysis was a research program in the foundations of mathematics carried out in the second half of the 19th century which aimed to abolish all geometric intuition from the proofs in analysis. For the followers of this program, the fundamental concepts of calculus should also not make references ... | https://en.wikipedia.org/wiki/Arithmetization_of_analysis |
Arithmologia, sive De Abditis Numerorum Mysteriis is a 1665 work by the Jesuit scholar Athanasius Kircher . It was published by Varese, the main printing house for the Jesuit order in Rome in the mid-17th century. [ 1 ] [ 2 ] It was dedicated to Franz III. Nádasdy , [ 3 ] a convert to Catholicism to whom Kircher had pr... | https://en.wikipedia.org/wiki/Arithmologia |
In logic , mathematics , and computer science , arity ( / ˈ ær ɪ t i / ⓘ ) is the number of arguments or operands taken by a function , operation or relation . In mathematics, arity may also be called rank, [ 1 ] [ 2 ] but this word can have many other meanings. In logic and philosophy , arity may also be called adicit... | https://en.wikipedia.org/wiki/Arity |
Arketamine (developmental code names PCN-101 , HR-071603 ), also known as ( R )-ketamine or ( R )-(−)-ketamine , is the ( R )-(−) enantiomer of ketamine . [ 1 ] [ 2 ] [ 3 ] Similarly to racemic ketamine and esketamine , the S (+) enantiomer of ketamine, arketamine is biologically active ; however, it is less potent as ... | https://en.wikipedia.org/wiki/Arketamine |
Planetary Resources, Inc. , formerly known as Arkyd Astronautics , was an American company that was formed on 1 January 2009, [ 1 ] [ 2 ] and reorganized and renamed in 2012. Its stated goal was to "expand Earth 's natural resource base" [ 3 ] by developing and deploying the technologies for asteroid mining .
Followin... | https://en.wikipedia.org/wiki/Arkyd-100 |
The arm and hammer is a symbol consisting of a muscular arm holding a hammer . Used in ancient times as a symbol of the god Vulcan , it came to be known as a symbol of industry , for example blacksmithing and gold-beating . It has been used as a symbol by many different kinds of organizations, including banks, local g... | https://en.wikipedia.org/wiki/Arm_and_hammer |
In the engineering field of robotics , an arm solution is a set of calculations that allow the real-time computation of the control commands needed to place the end of a robotic arm at a desired position and orientation in space.
A typical industrial robot is built with fixed length segments that are connected either ... | https://en.wikipedia.org/wiki/Arm_solution |
Armando Bukele Kattán (16 December 1944 – 30 November 2015) was a Salvadoran businessman of Palestinian origin, Muslim religious leader, and father of current Salvadoran president Nayib Bukele .
Armando Bukele Kattán was born in San Salvador, on 16 December 1944, the son of Humberto Bukele Salman and Victoria Kattán d... | https://en.wikipedia.org/wiki/Armando_Bukele_Kattán |
An armature is a kinematic chain used in computer animation to simulate the motions of virtual human or animal characters. In the context of animation, the inverse kinematics of the armature is the most relevant computational algorithm.
There are two types of digital armatures: Keyframing (stop-motion) armatures and r... | https://en.wikipedia.org/wiki/Armature_(computer_animation) |
The Armed Forces Radiobiology Research Institute (AFRRI) is an American triservice research laboratory in Bethesda, Maryland chartered by Congress in 1960 and formally established in 1961. [ 1 ] It conducts research in the field of radiobiology and related matters which are essential to the operational and medical supp... | https://en.wikipedia.org/wiki/Armed_Forces_Radiobiology_Research_Institute |
The armed/disarmed approach to glycosylation is an effective way to prevent sugar molecules from self-glycosylation when synthesizing disaccharides . This approach was first recognized when acetylated sugars only acted as glycosyl acceptors when reacted with benzylated sugars. The acetylated sugars were termed “disarme... | https://en.wikipedia.org/wiki/Armed_and_disarmed_saccharides |
The Armenian eternity sign (⟨֎ ֍⟩, Armenian : Հավերժության նշան , romanized : haverzhut’yan nshan ) or Arevakhach ( Արեւախաչ , "Sun Cross") is an ancient Armenian national symbol and a symbol of the national identity of the Armenian people . [ 1 ] It is one of the most common symbols in Armenian architecture , [ 2 ] [ ... | https://en.wikipedia.org/wiki/Armenian_eternity_sign |
Armesocarb (developmental code name MLR-1019 ), also known as ( R )-mesocarb or L -mesocarb , is a selective atypical dopamine reuptake inhibitor (DRI). It is currently under development for the treatment of Parkinson's disease and sleep disorders . [ 1 ] [ 2 ]
It is the active ( R )- enantiomer of the formerly clinic... | https://en.wikipedia.org/wiki/Armesocarb |
An armillary sphere (variations are known as spherical astrolabe , armilla , or armil ) is a model of objects in the sky (on the celestial sphere ), consisting of a spherical framework of rings , centered on Earth or the Sun , that represent lines of celestial longitude and latitude and other astronomically important f... | https://en.wikipedia.org/wiki/Armillary_sphere |
An arming plug is a small plug that is fitted into flight hardware to enable functions that, for instrument or personnel safety, should not be activated before flight. In the case of a missile or bomb , the (lack of the) arming plug prevents explosion before flight; in the case of a spacecraft or scientific sounding r... | https://en.wikipedia.org/wiki/Arming_plug |
Armitage is a graphical cyber attack management tool for the Metasploit Project that visualizes targets and recommends exploits. It is a free and open source network security tool notable for its contributions to red team collaboration allowing for: shared sessions, data, and communication through a single Metasploit i... | https://en.wikipedia.org/wiki/Armitage_(computing) |
Armodafinil , sold under the brand name Nuvigil , is a wakefulness-promoting medication which is used to treat excessive daytime sleepiness associated with obstructive sleep apnea , narcolepsy , and shift work disorder . [ 1 ] It is also used off-label for certain other indications. [ 10 ] The drug is taken by mouth . ... | https://en.wikipedia.org/wiki/Armodafinil |
The Armor Survivability Kit (ASK) is an armor kit developed by the U.S. Army Research Laboratory (ARL) in 2003 to protect vehicles like the Humvee from small arms, explosive device fragments, and rocket-propelled grenades (RPGs).
The Armor Survivability Kit consisted of armored steel doors with bullet-proof glass, pro... | https://en.wikipedia.org/wiki/Armor_Survivability_Kit |
Armor or armour in animals is a rigid cuticle or exoskeleton that provides exterior protection against attack by predators , [ 1 ] formed as part of the body (rather than the behavioural utilization of external objects for protection) usually through the thickening and hardening of superficial tissues , outgrowths or s... | https://en.wikipedia.org/wiki/Armour_(zoology) |
Armstrong's acid (naphthalene-1,5-disulfonic acid) is a fluorescent organic compound with the formula C 10 H 6 (SO 3 H) 2 . It is one of several isomers of naphthalenedisulfonic acid. It a colorless solid, typically obtained as the tetrahydrate. [ 1 ] Like other sulfonic acids , it is a strong acid. It is named for B... | https://en.wikipedia.org/wiki/Armstrong's_acid |
Armstrong's mixture is a highly shock and friction sensitive [ 1 ] explosive . Formulations vary, but one consists of 67% potassium chlorate , 27% red phosphorus , 3% sulfur , and 3% calcium carbonate . [ 2 ] [ 3 ] It is named for Sir William Armstrong , who invented it sometime prior to 1872 for use in explosive shell... | https://en.wikipedia.org/wiki/Armstrong's_mixture |
The Armstrong process is used to refine titanium . Its output is particle-sized dust which can be sprayed into pattern-molds. [ 1 ] [ 2 ] [ 3 ] It was patented in 1999. [ 4 ] The output of this process has a " coral -like morphology ", which differs from the traditional outputs like "spherical gas-atomized powder, mech... | https://en.wikipedia.org/wiki/Armstrong_process |
Army engineering maintenance consists of those engineers , technicians , and military organizations responsible for the expert repair and maintenance of army vehicles, weapon systems, and other equipment.
Army engineering maintenance should not be confused with military engineering which is distinctly separate and an... | https://en.wikipedia.org/wiki/Army_engineering_maintenance |
Arndt Simon (born 14 January 1940) is a German inorganic chemist . [ 1 ] He was a director at the Max Planck Institute for Solid State Research in Stuttgart. [ 2 ]
Simon studied Chemistry at the University of Münster from 1960-1964. [ 2 ] He worked on his doctoral thesis in the group of Harald Schäfer from 1964-1966 a... | https://en.wikipedia.org/wiki/Arndt_Simon |
In organic chemistry , the Arndt–Eistert reaction is the conversion of a carboxylic acid to its homologue . It is named for the German chemists Fritz Arndt (1885–1969) and Bernd Eistert (1902–1978). The method entails treating an acid chloride with diazomethane . It is a popular method of producing β-amino acids from α... | https://en.wikipedia.org/wiki/Arndt–Eistert_reaction |
Arne Magnéli (6 December 1914 – 22 July 1996) was a Swedish chemist and crystallographer known for his work on the structure determination of transition metal oxides and alloys , including the study into their homologous series and nonstoichiometric phenomenon . [ 1 ]
Magnéli studied at Stockholm University and gradua... | https://en.wikipedia.org/wiki/Arne_Magnéli |
In mathematics , Arnold's spectral sequence (also spelled Arnol'd ) is a spectral sequence used in singularity theory and normal form theory as an efficient computational tool for reducing a function to canonical form near critical points . It was introduced by Vladimir Arnold in 1975. [ 1 ] [ 2 ] [ 3 ]
This algebra -... | https://en.wikipedia.org/wiki/Arnold's_spectral_sequence |
Arnold Guloy is an American chemist who is Professor of Chemistry at the University of Houston . [ 1 ] He is an expert in the area Zintl phases chemistry, crystal growth, materials discovery, and superconductivity.
Guloy completed his undergraduate studies at the University of the Philippines in 1985. He earned his do... | https://en.wikipedia.org/wiki/Arnold_Guloy |
Arnold Jay Levine (born 1939) is an American molecular biologist . He was awarded the 1998 Louisa Gross Horwitz Prize for Biology or Biochemistry and was the first recipient of the Albany Medical Center Prize in Medicine and Biomedical Research in 2001 for his discovery of the tumor suppressor protein p53 . [ 1 ]
He i... | https://en.wikipedia.org/wiki/Arnold_J._Levine |
In applied mathematics , Arnold diffusion is the phenomenon of instability of nearly- integrable Hamiltonian systems . The phenomenon is named after Vladimir Arnold who was the first to publish a result in the field in 1964. [ 1 ] [ 2 ] More precisely, Arnold diffusion refers to results asserting the existence of solu... | https://en.wikipedia.org/wiki/Arnold_diffusion |
In mathematics , particularly in topology and knot theory , Arnold invariants are invariants introduced by Vladimir Arnold in 1994 [ 1 ] for studying the topology and geometry of plane curves . The three main invariants— J + {\displaystyle J^{+}} , J − {\displaystyle J^{-}} , and S t {\displaystyle St} —provide ways to... | https://en.wikipedia.org/wiki/Arnold_invariants |
The Arnold–Beltrami–Childress ( ABC ) flow or Gromeka–Arnold–Beltrami–Childress ( GABC ) flow is a three-dimensional incompressible velocity field which is an exact solution of Euler's equation . It is named after Vladimir Arnold , Eugenio Beltrami , and Stephen Childress . Ippolit S. Gromeka 's (1881) [ 1 ] name has b... | https://en.wikipedia.org/wiki/Arnold–Beltrami–Childress_flow |
An aroma compound , also known as an odorant , aroma , fragrance , flavoring or flavor , is a chemical compound that has a smell or odor . For an individual chemical or class of chemical compounds to impart a smell or fragrance, it must be sufficiently volatile for transmission via the air to the olfactory system in th... | https://en.wikipedia.org/wiki/Aroma_compound |
Aromatic acids are a type of aromatic compound . Included in that class are substances containing an aromatic ring and an organic acid functional group .
There are several categories of aromatic acids including:
This organic chemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Aromatic_acid |
An aromatic ring current is an effect observed in aromatic molecules such as benzene and naphthalene . If a magnetic field is directed perpendicular to the plane of the aromatic system, a ring current is induced in the delocalized π electrons of the aromatic ring. [ 1 ] This is a direct consequence of Ampère's law ; si... | https://en.wikipedia.org/wiki/Aromatic_ring_current |
In organic chemistry , aromaticity is a chemical property describing the way in which a conjugated ring of unsaturated bonds , lone pairs , or empty orbitals exhibits a stabilization stronger than would be expected from conjugation alone. The earliest use of the term was in an article by August Wilhelm Hofmann in 1855... | https://en.wikipedia.org/wiki/Aromaticity |
Aromatization is a chemical reaction in which an aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cyclohexane into benzene . Aromatization includes the formation of heterocyclic systems.... | https://en.wikipedia.org/wiki/Aromatization |
" Aromatoleum " is a genus of bacteria capable of microbial biodegradation of organic pollutants. It has one single described species member, A. aromaticum , for which the only strain is strain EbN1.
This taxonomy is accepted by the NCBI taxonomy database, and consequently by many bioinformatic databases. However, the... | https://en.wikipedia.org/wiki/Aromatoleum |
Aron Walsh is a chemist known for his research in the fields of computational chemistry and materials science. [ 1 ]
Walsh received his undergraduate degree in computational chemistry and physics from Trinity College Dublin . He went on to complete his PhD in chemistry at the same institution. [ 2 ] His postdoctoral r... | https://en.wikipedia.org/wiki/Aron_Walsh |
In mathematical set theory , an Aronszajn line (named after Nachman Aronszajn ) is a linear ordering of cardinality ℵ 1 {\displaystyle \aleph _{1}} which contains no subset order-isomorphic to
Unlike Suslin lines , the existence of Aronszajn lines is provable using the standard axioms of set theory. A linear ordering ... | https://en.wikipedia.org/wiki/Aronszajn_line |
Arotinoid acid ( TTNPB , Ro 13-7410 ) is an experimental drug which is a synthetic retinoid derivative. It was originally developed for potential medical applications in cancer treatment, but was not adopted due to potent teratogenic activity. However it has since been found to be useful as part of a cocktail of signal... | https://en.wikipedia.org/wiki/Arotinoid_acid |
In geometry and combinatorics , an arrangement of hyperplanes is an arrangement of a finite set A of hyperplanes in a linear , affine , or projective space S .
Questions about a hyperplane arrangement A generally concern geometrical, topological, or other properties of the complement , M ( A ), which is the set that ... | https://en.wikipedia.org/wiki/Arrangement_of_hyperplanes |
An arrastra (or arastra) is a primitive mill for grinding and pulverizing (typically) gold or silver ore . Its simplest form is two or more flat-bottomed drag stones placed in a circular pit paved with flat stones, and connected to a center post by a long arm. With a horse, mule or human providing power at the other en... | https://en.wikipedia.org/wiki/Arrastra |
ArrayTrack is a multi-purpose bioinformatics tool primarily used for microarray data management, analysis, and interpretation. ArrayTrack was developed to support in-house filter array research for the U.S. Food and Drug Administration in 2001, and was made freely available to the public as an integrated research tool ... | https://en.wikipedia.org/wiki/ArrayTrack |
The Array of Low Energy X-ray Imaging Sensors ( ALEXIS , also known as P89-1B , COSPAR 1993-026A, SATCAT 22638) X-ray telescope featured curved mirrors whose multilayer coatings reflected and focused low-energy X-rays or extreme ultraviolet (EUV) light the way optical telescopes focus visible light. The satellite and p... | https://en.wikipedia.org/wiki/Array_of_Low_Energy_X-ray_Imaging_Sensors |
The Arrhenius Plaque (Swedish: Arrhenius-plaketten ) is awarded annually by the Swedish Chemical Society in memory of Svante Arrhenius , [ 1 ] a Swedish physicist, chemist, and long-time member of the society, "to a person or persons who have distinguished themselves through outstanding research in the field of chemist... | https://en.wikipedia.org/wiki/Arrhenius_Plaque |
In physical chemistry , the Arrhenius equation is a formula for the temperature dependence of reaction rates . The equation was proposed by Svante Arrhenius in 1889, based on the work of Dutch chemist Jacobus Henricus van 't Hoff who had noted in 1884 that the Van 't Hoff equation for the temperature dependence of equi... | https://en.wikipedia.org/wiki/Arrhenius_equation |
In chemical kinetics , an Arrhenius plot displays the logarithm of a reaction rate constant , ( ln ( k ) {\displaystyle \ln(k)} , ordinate axis) plotted against reciprocal of the temperature ( 1 / T {\displaystyle 1/T} , abscissa ). [ 1 ] Arrhenius plots are often used to analyze the effect of temperature on the rate... | https://en.wikipedia.org/wiki/Arrhenius_plot |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.