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A still is an apparatus used to distill liquid mixtures by heating to selectively boil and then cooling to condense the vapor . [ 1 ] A still uses the same concepts as a basic distillation apparatus , but on a much larger scale. Stills have been used to produce perfume and medicine , water for injection (WFI) for pharm... | https://en.wikipedia.org/wiki/Still |
The Stille reaction is a chemical reaction widely used in organic synthesis . The reaction involves the coupling of two organic groups, one of which is carried as an organotin compound (also known as organostannanes ). A variety of organic electrophiles provide the other coupling partner . The Stille reaction is one of... | https://en.wikipedia.org/wiki/Stille_reaction |
Stilts are poles, posts or pillars used to allow a structure or building to stand at a distance above the ground or water. In flood plains, and on beaches or unstable ground, buildings are often constructed on stilts to protect them from damage by water, waves or shifting soil or sand. As these issues were commonly fac... | https://en.wikipedia.org/wiki/Stilts_(architecture) |
In quantum optics , stimulated Raman adiabatic passage ( STIRAP ) is a process that permits transfer of a population between two applicable quantum states via at least two coherent electromagnetic (light) pulses . [ 1 ] [ 2 ] These light pulses drive the transitions of the three level Ʌ atom or multilevel system. [ 3 ]... | https://en.wikipedia.org/wiki/Stimulated_Raman_adiabatic_passage |
Stimulated emission is the process by which an incoming photon of a specific frequency can interact with an excited atomic electron (or other excited molecular state), causing it to drop to a lower energy level. The liberated energy transfers to the electromagnetic field, creating a new photon with a frequency , polari... | https://en.wikipedia.org/wiki/Stimulated_emission |
Stimulus-triggered acquisition of pluripotency ( STAP ) was a proposed method of generating pluripotent stem cells by subjecting ordinary cells to certain types of stress, such as the application of a bacterial toxin, submersion in a weak acid, or physical trauma. [ 1 ] [ 2 ] The technique gained prominence in January ... | https://en.wikipedia.org/wiki/Stimulus-triggered_acquisition_of_pluripotency |
A stinging plant or a plant with stinging hairs is a plant with hairs ( trichomes ) on its leaves or stems that are capable of injecting substances that cause pain or irritation.
Other plants, such as opuntias , have hairs or spines that cause mechanical irritation, but do not inject chemicals. Stinging hairs occur pa... | https://en.wikipedia.org/wiki/Stinging_plant |
The StingRay is an IMSI-catcher , a cellular phone surveillance device, manufactured by Harris Corporation . [ 2 ] Initially developed for the military and intelligence community, the StingRay and similar Harris devices are in widespread use by local and state law enforcement agencies across Canada, [ 3 ] the United St... | https://en.wikipedia.org/wiki/Stingray_phone_tracker |
A stink bomb , sometimes called a stinkpot , is a device designed to create an unpleasant smell . They range in effectiveness from being used as simple pranks [ 1 ] to military grade malodorants or riot control chemical agents .
A stink bomb that could be launched with arrows was invented by Leonardo da Vinci . [ 2 ]
... | https://en.wikipedia.org/wiki/Stink_bomb |
A stipulative definition is a type of definition in which a new or currently existing term is given a new specific meaning for the purposes of argument or discussion in a given context. When the term already exists, this definition may, but does not necessarily, contradict the dictionary ( lexical ) definition of the t... | https://en.wikipedia.org/wiki/Stipulative_definition |
In mathematics , Stirling's approximation (or Stirling's formula ) is an asymptotic approximation for factorials . It is a good approximation, leading to accurate results even for small values of n {\displaystyle n} . It is named after James Stirling , though a related but less precise result was first stated by Abraha... | https://en.wikipedia.org/wiki/Stirling's_approximation |
In mathematics , especially in combinatorics , Stirling numbers of the first kind arise in the study of permutations. In particular, the unsigned Stirling numbers of the first kind count permutations according to their number of cycles (counting fixed points as cycles of length one). [ 1 ]
The Stirling numbers of the... | https://en.wikipedia.org/wiki/Stirling_numbers_of_the_first_kind |
In mathematics , particularly in combinatorics , a Stirling number of the second kind (or Stirling partition number ) is the number of ways to partition a set of n objects into k non-empty subsets and is denoted by S ( n , k ) {\displaystyle S(n,k)} or { n k } {\displaystyle \textstyle \left\{{n \atop k}\right\}} . [ 1... | https://en.wikipedia.org/wiki/Stirling_numbers_of_the_second_kind |
In mathematics , the Stirling polynomials are a family of polynomials that generalize important sequences of numbers appearing in combinatorics and analysis , which are closely related to the Stirling numbers , the Bernoulli numbers , and the generalized Bernoulli polynomials . There are multiple variants of the Stirli... | https://en.wikipedia.org/wiki/Stirling_polynomials |
The Stobbe condensation entails the reaction of an aldehyde or ketone with an ester of succinic acid to generate alkylidene succinic acid or related derivatives. [ 1 ] The reaction consumes one equivalent of metal alkoxide. Commonly, diethylsuccinate is a component of the reaction. The usual product is salt of the hal... | https://en.wikipedia.org/wiki/Stobbe_condensation |
Stochastic ( / s t ə ˈ k æ s t ɪ k / ; from Ancient Greek στόχος ( stókhos ) ' aim, guess ' ) [ 1 ] is the property of being well-described by a random probability distribution . [ 1 ] Stochasticity and randomness are technically distinct concepts: the former refers to a modeling approach, while the latter describes ph... | https://en.wikipedia.org/wiki/Stochastic |
Stochastic Gronwall inequality is a generalization of Gronwall's inequality and has been used for proving the well-posedness of path-dependent stochastic differential equations with local monotonicity and coercivity assumption with respect to supremum norm. [ 1 ] [ 2 ]
Let X ( t ) , t ≥ 0 {\displaystyle X(t),\,t\geq 0... | https://en.wikipedia.org/wiki/Stochastic_Gronwall_inequality |
Stochastic calculus is a branch of mathematics that operates on stochastic processes . It allows a consistent theory of integration to be defined for integrals of stochastic processes with respect to stochastic processes. This field was created and started by the Japanese mathematician Kiyosi Itô during World War II .
... | https://en.wikipedia.org/wiki/Stochastic_calculus |
A stochastic differential equation ( SDE ) is a differential equation in which one or more of the terms is a stochastic process , [ 1 ] resulting in a solution which is also a stochastic process. SDEs have many applications throughout pure mathematics and are used to model various behaviours of stochastic models such a... | https://en.wikipedia.org/wiki/Stochastic_differential_equation |
The stochastic empirical loading and dilution model ( SELDM ) [ 1 ] [ 2 ] [ 3 ] is a stormwater quality model. SELDM is designed to transform complex scientific data into meaningful information about the risk of adverse effects of runoff on receiving waters, the potential need for mitigation measures, and the potential... | https://en.wikipedia.org/wiki/Stochastic_empirical_loading_and_dilution_model |
Stochastic multicriteria acceptability analysis ( SMAA ) is a multiple-criteria decision analysis method for problems with missing or incomplete information.
This means that criteria and preference information can be uncertain, inaccurate or partially missing. Incomplete information is represented in SMAA using suitab... | https://en.wikipedia.org/wiki/Stochastic_multicriteria_acceptability_analysis |
Stochastic portfolio theory ( SPT ) is a mathematical theory for analyzing stock market structure and portfolio behavior introduced by E. Robert Fernholz in 2002. It is descriptive as opposed to normative, and is consistent with the observed behavior of actual markets. Normative assumptions, which serve as a basis fo... | https://en.wikipedia.org/wiki/Stochastic_portfolio_theory |
Stochastic-process rare event sampling (SPRES) is a rare-event sampling method in computer simulation , designed specifically for non-equilibrium calculations, including those for which the rare-event rates are time-dependent ( non-stationary process). To treat systems in which there is time dependence in the dynamics,... | https://en.wikipedia.org/wiki/Stochastic_process_rare_event_sampling |
Stochastic resonance ( SR ) is the description of a physical phenomenon where the behavior of non-linear system where random (stochastic) fluctuations in the micro state cause deterministic changes in the macro state. This occurs when the non-linear nature of the system amplifies certain (resonant) portions of the fluc... | https://en.wikipedia.org/wiki/Stochastic_resonance |
Stochastic resonance is a phenomenon that occurs in a threshold measurement system (e.g. a man-made instrument or device; a natural cell, organ or organism) when an appropriate measure of information transfer ( signal-to-noise ratio , mutual information , coherence , d' , etc.) is maximized in the presence of a non-zer... | https://en.wikipedia.org/wiki/Stochastic_resonance_(sensory_neurobiology) |
Stochastic thermodynamics is an emergent field of research in statistical mechanics that uses stochastic variables to better understand the non-equilibrium dynamics present in many microscopic systems [ 1 ] such as colloidal particles , biopolymers (e.g. DNA , RNA , and proteins ), enzymes , and molecular motors . [ a ... | https://en.wikipedia.org/wiki/Stochastic_thermodynamics |
Stock nomenclature for inorganic compounds is a widely used system of chemical nomenclature developed by the German chemist Alfred Stock and first published in 1919. In the "Stock system", the oxidation states of some or all of the elements in a compound are indicated in parentheses by Roman numerals . [ 1 ] [ 2 ]
Con... | https://en.wikipedia.org/wiki/Stock_nomenclature |
Stockholm Convention on Persistent Organic Pollutants is an international environmental treaty , signed on 22 May 2001 in Stockholm and effective from 17 May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants (POPs). [ 2 ]
In 1995, the Governing Council of the United Natio... | https://en.wikipedia.org/wiki/Stockholm_Convention_on_Persistent_Organic_Pollutants |
Stockholm format is a multiple sequence alignment format used by Pfam , Rfam and Dfam , to disseminate protein, RNA and DNA sequence alignments. [ 1 ] [ 2 ] [ 3 ] The alignment editors Ralee , [ 4 ] Belvu and Jalview support Stockholm format as do the probabilistic database search tools , Infernal and HMMER , and the p... | https://en.wikipedia.org/wiki/Stockholm_format |
The Stockmayer potential is a mathematical model for representing the interactions between pairs of atoms or molecules . It is defined as a Lennard-Jones potential with a point electric dipole moment .
A Stockmayer liquid consists of a collection of spheres with point dipoles embedded at the centre of each. These sphe... | https://en.wikipedia.org/wiki/Stockmayer_potential |
The stocks-to-use ratio (S/U) is a convenient measure of supply and demand interrelationships of commodities . This ratio indicates the level of carryover stock for any given commodity as a percentage of the total use of the commodity.
It is typically used for grain commodity stocks such as wheat , corn and soybeans ... | https://en.wikipedia.org/wiki/Stocks-to-use_ratio |
Air–fuel ratio ( AFR ) is the mass ratio of air to a solid, liquid, or gaseous fuel present in a combustion process. The combustion may take place in a controlled manner such as in an internal combustion engine or industrial furnace, or may result in an explosion (e.g., a dust explosion ). The air–fuel ratio determine... | https://en.wikipedia.org/wiki/Stoichiometric_air_ratio |
Stoichiometry ( / ˌ s t ɔɪ k i ˈ ɒ m ɪ t r i / ⓘ ) is the relationships between the masses of reactants and products before, during, and following chemical reactions .
Stoichiometry is based on the law of conservation of mass ; the total mass of reactants must equal the total mass of products, so the relationship betw... | https://en.wikipedia.org/wiki/Stoichiometry |
In fluid dynamics , Stokes' law gives the frictional force – also called drag force – exerted on spherical objects moving at very small Reynolds numbers in a viscous fluid . [ 1 ] It was derived by George Gabriel Stokes in 1851 by solving the Stokes flow limit for small Reynolds numbers of the Navier–Stokes equations .... | https://en.wikipedia.org/wiki/Stokes'_law |
In the science of fluid flow , Stokes' paradox is the phenomenon that there can be no creeping flow of a fluid around a disk in two dimensions; or, equivalently, the fact there is no non-trivial steady-state solution for the Stokes equations around an infinitely long cylinder. This is opposed to the 3-dimensional case,... | https://en.wikipedia.org/wiki/Stokes'_paradox |
Stokes' theorem , [ 1 ] also known as the Kelvin–Stokes theorem [ 2 ] [ 3 ] after Lord Kelvin and George Stokes , the fundamental theorem for curls , or simply the curl theorem , [ 4 ] is a theorem in vector calculus on R 3 {\displaystyle \mathbb {R} ^{3}} . Given a vector field , the theorem relates the integral of th... | https://en.wikipedia.org/wiki/Stokes'_theorem |
In acoustics , Stokes's law of sound attenuation is a formula for the attenuation of sound in a Newtonian fluid , such as water or air, due to the fluid's viscosity . It states that the amplitude of a plane wave decreases exponentially with distance traveled, at a rate α given by α = 2 η ω 2 3 ρ V 3 {\displaystyle \al... | https://en.wikipedia.org/wiki/Stokes's_law_of_sound_attenuation |
This article provides an error analysis of time discretization applied to spatially discrete approximation of the stationary and nonstationary Navier-Stokes equations . The nonlinearity of the convection term is the main problem in solving a stationary or nonstationary Navier-Stokes equation or Euler equation problems.... | https://en.wikipedia.org/wiki/Stokes_approximation_and_artificial_time |
For a pure wave motion in fluid dynamics , the Stokes drift velocity is the average velocity when following a specific fluid parcel as it travels with the fluid flow . For instance, a particle floating at the free surface of water waves , experiences a net Stokes drift velocity in the direction of wave propagation .
M... | https://en.wikipedia.org/wiki/Stokes_drift |
Stokes flow (named after George Gabriel Stokes ), also named creeping flow or creeping motion , [ 1 ] is a type of fluid flow where advective inertial forces are small compared with viscous forces. [ 2 ] The Reynolds number is low, i.e. R e ≪ 1 {\displaystyle \mathrm {Re} \ll 1} . This is a typical situation in flows w... | https://en.wikipedia.org/wiki/Stokes_flow |
The Stokes number ( Stk ), named after George Gabriel Stokes , is a dimensionless number characterising the behavior of particles suspended in a fluid flow . The Stokes number is defined as the ratio of the characteristic time of a particle (or droplet ) to a characteristic time of the flow or of an obstacle, or
S t ... | https://en.wikipedia.org/wiki/Stokes_number |
The Stokes operator , named after George Gabriel Stokes , is an unbounded linear operator used in the theory of partial differential equations , specifically in the fields of fluid dynamics and electromagnetics .
If we define P σ {\displaystyle P_{\sigma }} as the Leray projection onto divergence free vector fields , ... | https://en.wikipedia.org/wiki/Stokes_operator |
In fluid dynamics, Stokes problem also known as Stokes second problem or sometimes referred to as Stokes boundary layer or Oscillating boundary layer is a problem of determining the flow created by an oscillating solid surface, named after Sir George Stokes . This is considered one of the simplest unsteady problems tha... | https://en.wikipedia.org/wiki/Stokes_problem |
The Stokes radius or Stokes–Einstein radius of a solute is the radius of a hard sphere that diffuses at the same rate as that solute. Named after George Gabriel Stokes , it is closely related to solute mobility, factoring in not only size but also solvent effects. A smaller ion with stronger hydration, for example, may... | https://en.wikipedia.org/wiki/Stokes_radius |
In fluid dynamics , the Stokes stream function is used to describe the streamlines and flow velocity in a three-dimensional incompressible flow with axisymmetry . A surface with a constant value of the Stokes stream function encloses a streamtube , everywhere tangential to the flow velocity vectors. Further, the volume... | https://en.wikipedia.org/wiki/Stokes_stream_function |
In fluid dynamics , a Stokes wave is a nonlinear and periodic surface wave on an inviscid fluid layer of constant mean depth.
This type of modelling has its origins in the mid 19th century when Sir George Stokes – using a perturbation series approach, now known as the Stokes expansion – obtained approximate solutions f... | https://en.wikipedia.org/wiki/Stokes_wave |
The Stollé synthesis is a series of chemical reactions that produce oxindoles from anilines and α-haloacid chlorides (or oxalyl chloride ). [ 1 ] [ 2 ] [ 3 ] [ 4 ]
The first step is an amide coupling, while the second step is a Friedel–Crafts reaction . [ 5 ] [ 6 ] An improved procedure has been developed. [ 7 ] [ 8 ] | https://en.wikipedia.org/wiki/Stollé_synthesis |
The Stolper–Samuelson theorem is a theorem in Heckscher–Ohlin trade theory. It describes the relationship between relative prices of output and relative factor returns—specifically, real wages and real returns to capital.
The theorem states that—under specific economic assumptions (constant returns to scale , perfect ... | https://en.wikipedia.org/wiki/Stolper–Samuelson_theorem |
In botany , a stoma ( pl. : stomata , from Greek στόμα , "mouth"), also called a stomate ( pl. : stomates ), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange between the internal air spaces of the leaf and the atmosphere. The pore is bordered by a pair of speci... | https://en.wikipedia.org/wiki/Stoma |
Stomach oil is the light oil composed of neutral dietary lipids found in the proventriculus (fore-gut) of birds in the order Procellariiformes . All albatrosses , procellarids (gadfly petrels and shearwaters) and northern and austral storm petrels use the oil. The only Procellariiformes that do not are the diving petre... | https://en.wikipedia.org/wiki/Stomach_oil |
The Stomatophyta are a proposed sister branch of the Marchantiophyta (Liverworts), together forming the Embryophyta . [ 1 ] The Stomatophyta consist of the Bryophyta ( Moss ), and the remainder of the Embryophyta, including the Anthocerotophyta (Hornsworts). The word stomatophyta means plant with stoma . [ citation nee... | https://en.wikipedia.org/wiki/Stomatophyta |
Stone Aerospace is an aerospace engineering firm founded by engineer and explorer Bill Stone , located in Del Valle , a suburb of Austin, Texas . [ 1 ]
Bill Stone began Stone Aerospace as a part-time consulting business in 1999, at which time he was working at the National Institute of Standards and Technology . At t... | https://en.wikipedia.org/wiki/Stone_Aerospace |
In mathematics , a Stone algebra or Stone lattice is a pseudocomplemented distributive lattice L in which any of the following equivalent statements hold for all x , y ∈ L : {\displaystyle x,y\in L:} [ 1 ]
They were introduced by Grätzer & Schmidt (1957) and named after Marshall Harvey Stone .
The set S ( L ) ≝ { x *... | https://en.wikipedia.org/wiki/Stone_algebra |
Stone sealing is the application of a surface treatment to products constructed of natural stone to retard staining and corrosion. [ 1 ] All bulk natural stone is riddled with interconnected capillary channels that permit penetration by liquids and gases. This is true for igneous rock types such as granite and basalt ,... | https://en.wikipedia.org/wiki/Stone_sealer |
In mathematics , the Stoneham numbers are a certain class of real numbers , named after mathematician Richard G. Stoneham (1920–1996). [ 1 ] For coprime numbers b , c > 1, the Stoneham number α b , c is defined as
It was shown by Stoneham in 1973 that α b , c is b - normal whenever c is an odd prime and b is a primiti... | https://en.wikipedia.org/wiki/Stoneham_number |
A Stone–Wales defect is a crystallographic defect that involves the change of connectivity of two π-bonded carbon atoms, leading to their rotation by 90° with respect to the midpoint of their bond. [ 1 ] The reaction commonly involves conversion between a naphthalene -like structure into a fulvalene -like structure, th... | https://en.wikipedia.org/wiki/Stone–Wales_defect |
In mathematical analysis , the Weierstrass approximation theorem states that every continuous function defined on a closed interval [ a , b ] can be uniformly approximated as closely as desired by a polynomial function. Because polynomials are among the simplest functions, and because computers can directly evaluate po... | https://en.wikipedia.org/wiki/Stone–Weierstrass_theorem |
In mathematics and in theoretical physics , the Stone–von Neumann theorem refers to any one of a number of different formulations of the uniqueness of the canonical commutation relations between position and momentum operators . It is named after Marshall Stone and John von Neumann . [ 1 ] [ 2 ] [ 3 ] [ 4 ]
In quantum... | https://en.wikipedia.org/wiki/Stone–von_Neumann_theorem |
In mathematics , the Stone–Čech remainder of a topological space X , also called the corona or corona set , is the complement β X \ X of the space in its Stone–Čech compactification β X .
A topological space is said to be σ-compact if it is the union of countably many compact subspaces, and locally compact if every po... | https://en.wikipedia.org/wiki/Stone–Čech_remainder |
A Stonyhurst disk is a transparent circular grid with lines of longitude and latitude that can overlay a solar image to reference the positions of sunspots . This overlay system was originally created at the Stonyhurst College observatory . [ 1 ] [ 2 ]
This England -related article is a stub . You can help Wikipedia b... | https://en.wikipedia.org/wiki/Stonyhurst_disks |
Stop-and-wait ARQ , also referred to as alternating bit protocol , is a method in telecommunications to send information between two connected devices. It ensures that information is not lost due to dropped packets and that packets are received in the correct order. It is the simplest automatic repeat-request (ARQ) mec... | https://en.wikipedia.org/wiki/Stop-and-wait_ARQ |
In molecular biology , a stop codon (or termination codon ) is a codon ( nucleotide triplet within messenger RNA ) that signals the termination of the translation process of the current protein . [ 1 ] Most codons in messenger RNA correspond to the addition of an amino acid to a growing polypeptide chain, which may ult... | https://en.wikipedia.org/wiki/Stop_codon |
In telecommunications , a stop signal is a signal that marks the end of part of a transmission, for example:
This article incorporates public domain material from Federal Standard 1037C . General Services Administration . Archived from the original on 2022-01-22. (in support of MIL-STD-188 ).
This article related to ... | https://en.wikipedia.org/wiki/Stop_signal |
In particle physics , a stop squark , symbol t͂ , is the superpartner of the top quark as predicted by supersymmetry (SUSY). It is a sfermion , which means it is a spin-0 boson ( scalar boson ). While the top quark is the heaviest known quark, the stop squark is actually often the lightest squark in many supersymmetr... | https://en.wikipedia.org/wiki/Stop_squark |
Stoplogs are hydraulic engineering control elements that are used in floodgates to adjust the water level or discharge in a river , canal , or reservoir . Stoplogs are designed to cut off or stop flow through a conduit. They are typically long rectangular timber beams or boards that are placed on top of each other and ... | https://en.wikipedia.org/wiki/Stoplogs |
Stopped-flow is one of a number of methods of studying the kinetics of reactions in solution. It is ideal for studying chemical reactions with a typical dead time on the order of 1 millisecond. In the simplest form of the technique, the solutions of two reactants are rapidly mixed by being forced through a mixing chamb... | https://en.wikipedia.org/wiki/Stopped-flow |
Stopping and Range of Ions in Matter ( SRIM ) is a group of computer programs which calculate interactions between ions and matter ; the core of SRIM is a program called Transport of Ions in Matter ( TRIM ). SRIM is popular in the ion implantation research and technology community, and also used widely in other branche... | https://en.wikipedia.org/wiki/Stopping_and_Range_of_Ions_in_Matter |
In nuclear and materials physics , stopping power is the retarding force acting on charged particles , typically alpha and beta particles , due to interaction with matter , resulting in loss of particle kinetic energy . [ 1 ] [ 2 ] Stopping power is also interpreted as the rate at which a material absorbs the kinetic e... | https://en.wikipedia.org/wiki/Stopping_power_(particle_radiation) |
The storage effect is a coexistence mechanism proposed in the ecological theory of species coexistence, which tries to explain how such a wide variety of similar species are able to coexist within the same ecological community or guild . The storage effect was originally proposed in the 1980s [ 1 ] to explain coexisten... | https://en.wikipedia.org/wiki/Storage_effect |
A storage organ is a part of a plant specifically modified for storage of energy
(generally in the form of carbohydrates ) or water. [ 1 ] Storage organs often grow underground, where they are better protected from attack by herbivores . Plants that have an underground storage organ are called geophytes in the Raunkiæ... | https://en.wikipedia.org/wiki/Storage_organ |
Storage tanks are containers that hold liquids or compressed gases. The term can be used for reservoirs (artificial lakes and ponds), and for manufactured containers. The usage of the word "tank" for reservoirs is uncommon in American English but is moderately common in British English . In other countries, the term te... | https://en.wikipedia.org/wiki/Storage_tank |
A stored energy printer is a computer printer that uses the energy stored in a spring or magnetic field to push a hammer into a ribbon to print a dot. It is a type of impact printer. [ 1 ]
As compared to dot matrix printers that print a single column of dots at a time, this printer generally creates an entire line of ... | https://en.wikipedia.org/wiki/Stored_energy_printer |
The Stork enamine alkylation involves the addition of an enamine to a Michael acceptor (e.g., an α,β -unsaturated carbonyl compound ) or another electrophilic alkylation reagent to give an alkylated iminium product, which is hydrolyzed by dilute aqueous acid to give the alkylated ketone or aldehyde. [ 1 ] Since enamine... | https://en.wikipedia.org/wiki/Stork_enamine_alkylation |
A storm drain , storm sewer ( United Kingdom , U.S. and Canada ), highway drain , [ 1 ] surface water drain / sewer ( United Kingdom ), or stormwater drain ( Australia and New Zealand ) is infrastructure designed to drain excess rain and ground water from impervious surfaces such as paved streets, car parks, parking lo... | https://en.wikipedia.org/wiki/Storm_drain |
Storm hardening is the process whereby construction is used to create new infrastructure or retrofit existing infrastructure such that it is more capable of withstanding extreme weather events. It "involves physically changing infrastructure to make it less susceptible to damage from extreme wind , flooding , or flying... | https://en.wikipedia.org/wiki/Storm_hardening |
Storm oil is described as nearly water-insoluble oil acting as a surfactant , and has been used since ancient times to smooth ocean waves. [ 1 ] [ 2 ] It has been historically employed to facilitate sea rescues and improve navigational safety, involving pouring the oil onto the ocean surface to reduce wave intensity. [... | https://en.wikipedia.org/wiki/Storm_oil |
Stormtroopers Advance Under a Gas Attack (German: Sturmtruppe geht unter Gas vor ) is an engraving in aquatint by German painter and printmaker Otto Dix representing German soldiers in combat during the First World War . It is the twelfth in the series of fifty engravings entitled The War , published in 1924. Copies a... | https://en.wikipedia.org/wiki/Stormtroopers_Advance_Under_a_Gas_Attack |
Stormwater , also written storm water , is water that originates from precipitation ( storm ), including heavy rain and meltwater from hail and snow . Stormwater can soak into the soil ( infiltrate ) and become groundwater , be stored on depressed land surface in ponds and puddles , evaporate back into the atmosphere, ... | https://en.wikipedia.org/wiki/Stormwater |
A stormwater detention vault is an underground structure designed to manage excess stormwater runoff on a developed site, often in an urban setting. This type of best management practice may be selected when there is insufficient space on the site to infiltrate the runoff or build a surface facility such as a detentio... | https://en.wikipedia.org/wiki/Stormwater_detention_vault |
In engineering and computing , "stovepipe system" is a pejorative term for a system that has the potential to share data or functionality with other systems but which does not do so. The term evokes the image of stovepipes rising above buildings, each functioning individually. A simple example of a stovepipe system is ... | https://en.wikipedia.org/wiki/Stovepipe_system |
Str8ts is a logic -based number-placement puzzle , invented by Jeff Widderich in 2008. [ 1 ] It is distinct from, but shares some properties and rules with, Sudoku . The name is derived from the poker straight . The puzzle is published in a number of newspapers internationally, [ 2 ] in two book collections, and in dow... | https://en.wikipedia.org/wiki/Str8ts |
In mathematics , the Strahler number or Horton–Strahler number of a mathematical tree is a numerical measure of its branching complexity.
These numbers were first developed in hydrology , as a way of measuring the complexity of rivers and streams, by Robert E. Horton ( 1945 ) and Arthur Newell Strahler ( 1952 , 1957 )... | https://en.wikipedia.org/wiki/Strahler_number |
Straight-Through Quality ( STQ ) are approaches and outputs of test automation that have quality and deliver business benefit. STQ takes its name from the business concept of straight-through processing (STP). Also acting as a tool and enabler for STP.
Traditional techniques for testing and delivery have often require... | https://en.wikipedia.org/wiki/Straight-Through_Quality |
A straightedge or straight edge is a tool used for drawing straight lines, or checking their straightness. If it has equally spaced markings along its length, it is usually called a ruler .
Straightedges are used in the automotive service and machining industry to check the flatness of machined mating surfaces. They a... | https://en.wikipedia.org/wiki/Straightedge |
In differential calculus , the domain-straightening theorem states that, given a vector field X {\displaystyle X} on a manifold , there exist local coordinates y 1 , … , y n {\displaystyle y_{1},\dots ,y_{n}} such that X = ∂ / ∂ y 1 {\displaystyle X=\partial /\partial y_{1}} in a neighborhood of a point where X {\displ... | https://en.wikipedia.org/wiki/Straightening_theorem_for_vector_fields |
In biology , a strain is a genetic variant, a subtype or a culture within a biological species . Strains are often seen as inherently artificial concepts, characterized by a specific intent for genetic isolation. [ 1 ] This is most easily observed in microbiology where strains are derived from a single cell colony and ... | https://en.wikipedia.org/wiki/Strain_(biology) |
In chemistry , a molecule experiences strain when its chemical structure undergoes some stress which raises its internal energy in comparison to a strain-free reference compound . The internal energy of a molecule consists of all the energy stored within it. A strained molecule has an additional amount of internal en... | https://en.wikipedia.org/wiki/Strain_(chemistry) |
In mechanics , strain is defined as relative deformation , compared to a reference position configuration. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor ... | https://en.wikipedia.org/wiki/Strain_(mechanics) |
In physics , the elastic potential energy gained by a wire during elongation with a tensile (stretching) or compressive (contractile) force is called strain energy. For linearly elastic materials, strain energy is:
where σ is stress , ε is strain , V is volume, and E is Young's modulus :
In a molecule , strain energ... | https://en.wikipedia.org/wiki/Strain_energy |
The strain hardening exponent (also called the strain hardening index ), usually denoted n {\displaystyle n} , is a measured parameter that quantifies the ability of a material to become stronger due to strain hardening. Strain hardening (work hardening) is the process by which a material's load-bearing capacity increa... | https://en.wikipedia.org/wiki/Strain_hardening_exponent |
In mechanics and materials science , strain rate is the time derivative of strain of a material. Strain rate has dimension of inverse time and SI units of inverse second , s −1 (or its multiples).
The strain rate at some point within the material measures the rate at which the distances of adjacent parcels of the mate... | https://en.wikipedia.org/wiki/Strain_rate |
In physics , strain scanning is the general name for various techniques that aim to measure the strain in a crystalline material through its effect on the diffraction of X-rays and neutrons . In these methods the material itself is used as a form of strain gauge .
The various methods are derived from powder diffractio... | https://en.wikipedia.org/wiki/Strain_scanning |
Straintronics (from strain and electronics ) is the study of how folds and mechanically induced stresses in a layer of two-dimensional materials can change their electrical properties. [ 1 ] [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] [ 7 ] It is distinct from twistronics in that the latter involves changes in the angle between two ... | https://en.wikipedia.org/wiki/Straintronics |
The Strait of Sicily Tunnel is a proposed megaproject to link Sicily and Tunisia . The distance between the coastlines is about 155 kilometres (96 miles) and would be reached by five tunnels constructed between four intermediate artificial islands which will be built with the excavated material. A preliminary study was... | https://en.wikipedia.org/wiki/Strait_of_Sicily_Tunnel |
A strand jack (also known as strandjack ) is a jack used to lift very heavy loads (e.g. thousands of tons or more with multiple jacks) for construction and engineering purposes. [ 1 ] Strandjacking was invented by VSL Australia's Patrick Kilkeary & Bruce Ramsay in 1969 for concrete post tensioning systems, and is now w... | https://en.wikipedia.org/wiki/Strand_jack |
Strange matter (or strange quark matter ) is quark matter containing strange quarks . In extreme environments, strange matter is hypothesized to occur in the core of neutron stars , or, more speculatively, as isolated droplets that may vary in size from femtometers ( strangelets ) to kilometers, as in the hypothetical ... | https://en.wikipedia.org/wiki/Strange_matter |
A strange particle is an elementary particle with a strangeness quantum number different from zero. Strange particles are members of a large family of elementary particles carrying the quantum number of strangeness , including several cases where the quantum number is hidden in a strange/anti-strange pair, for example ... | https://en.wikipedia.org/wiki/Strange_particle |
A strangelet (pronounced / ˈ s t r eɪ n dʒ . l ɪ t / ) is a hypothetical particle consisting of a bound state of roughly equal numbers of up , down , and strange quarks . An equivalent description is that a strangelet is a small fragment of strange matter , small enough to be considered a particle . The size of an obje... | https://en.wikipedia.org/wiki/Strangelet |
In particle physics , strangeness (symbol S ) [ 1 ] [ 2 ] is a property of particles , expressed as a quantum number , for describing decay of particles in strong and electromagnetic interactions that occur in a short period of time . The strangeness of a particle is defined as: S = − ( n s − n s ¯ ) {\displaystyle S=-... | https://en.wikipedia.org/wiki/Strangeness |
In high-energy nuclear physics , strangeness production in relativistic heavy-ion collisions is a signature and diagnostic tool of quark–gluon plasma (QGP) formation and properties. [ 1 ] Unlike up and down quarks , from which everyday matter is made, heavier quark flavors such as strange and charm typically approach c... | https://en.wikipedia.org/wiki/Strangeness_and_quark–gluon_plasma |
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