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Spectroscopic notation provides a way to specify atomic ionization states , atomic orbitals , and molecular orbitals .
Spectroscopists customarily refer to the spectrum arising from a given ionization state of a given element by the element's symbol followed by a Roman numeral . The numeral I is used for spectral line... | https://en.wikipedia.org/wiki/Spectroscopic_notation |
Spectroscopy is the field of study that measures and interprets electromagnetic spectra . [ 1 ] [ 2 ] In narrower contexts, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum.
Spectroscopy, primarily in the electromagnetic spectrum, is a fundamenta... | https://en.wikipedia.org/wiki/Spectroscopy |
A spectrum ( pl. : spectra or spectrums ) is a set of related ideas, objects, or properties whose features overlap such that they blend to form a continuum . [ 1 ] The word spectrum was first used scientifically in optics to describe the rainbow of colors in visible light after passing through a prism . In the optical ... | https://en.wikipedia.org/wiki/Spectrum |
In the physical sciences , the term spectrum was introduced first into optics by Isaac Newton in the 17th century, referring to the range of colors observed when white light was dispersed through a prism . [ 1 ] [ 2 ] Soon the term referred to a plot of light intensity or power as a function of frequency or wavelength ... | https://en.wikipedia.org/wiki/Spectrum_(physical_sciences) |
Spectrum Pharmaceuticals, Inc. is an American biopharmaceutical company located in Boston, MA . It develops and markets drugs for treatments in hematology and oncology .
After a deal valued at $248 million was announced in April 2023, [ 1 ] [ 2 ] Assertio Holdings announced that it had completed its acquisition of the... | https://en.wikipedia.org/wiki/Spectrum_Pharmaceuticals |
A spectrum analyzer measures the magnitude of an input signal versus frequency within the full frequency range of the instrument. The primary use is to measure the power of the spectrum of known and unknown signals. The input signal that most common spectrum analyzers measure is electrical; however, spectral compositio... | https://en.wikipedia.org/wiki/Spectrum_analyzer |
A spectrum auction is a process whereby a government uses an auction system to sell the rights to transmit signals over specific bands of the electromagnetic spectrum and to assign scarce spectrum resources. Depending on the specific auction format used, a spectrum auction can last from a single day to several months f... | https://en.wikipedia.org/wiki/Spectrum_auction |
The Spectrum Commons theory states that the telecommunication radio spectrum should be directly managed by its users rather than regulated by governmental or private institutions. Spectrum management is the process of regulating the use of radio frequencies to promote efficient use and gain a net social benefit. [ 1 ] ... | https://en.wikipedia.org/wiki/Spectrum_commons_theory |
Spectrum continuation analysis (SCA) is a generalization of the concept of Fourier series to non-periodic functions of which only a fragment has been sampled in the time domain.
Recall that a Fourier series is only suitable to the analysis of periodic (or finite-domain) functions f ( x ) with period 2π. It can be expr... | https://en.wikipedia.org/wiki/Spectrum_continuation_analysis |
In model theory , a branch of mathematical logic , the spectrum of a theory is given by the number of isomorphism classes of models in various cardinalities . More precisely,
for any complete theory T in a language we write I ( T , κ ) for the number of models of T (up to isomorphism) of cardinality κ . The spectrum ... | https://en.wikipedia.org/wiki/Spectrum_of_a_theory |
Specula Melitensis Encyclica (“The Maltese Watchtower”) is a 1638 book by Fra Salvatore Imbroll, describing a machine invented by a Jesuit scholar Athanasius Kircher . It was printed in Naples by Secundino Roncagliolo [ 1 ] and dedicated to Giovanni Paolo Lascaris , Grand Master of the Knights of Malta . [ 2 ]
The boo... | https://en.wikipedia.org/wiki/Specula_Melitensis_Encyclica |
Speculative design is a design practice concerned with future design proposals of a critical nature. The term was popularised by Anthony Dunne and Fiona Raby as a subsidiary of critical design . The aim is not to present commercially-driven design proposals but to design proposals that identify and debate crucial issue... | https://en.wikipedia.org/wiki/Speculative_design |
A speech droplet or speaking droplet is a particle of saliva involuntarily expelled from the mouth during speech, especially during vigorous articulation or the pronunciation of explosive consonants (such as /p/, /b/, /t/). These droplets, distinct from respiratory droplets , are produced by fluid dynamics in the oral ... | https://en.wikipedia.org/wiki/Speech_droplet |
Speed bumps (also called traffic thresholds , speed breakers or sleeping policemen ) are a class of traffic calming devices that use vertical deflection to slow motor-vehicle traffic in order to improve safety conditions. Variations include the speed hump , speed cushion , and speed table .
The use of vertical deflect... | https://en.wikipedia.org/wiki/Speed_bump |
In telecommunication, speed of service is the time for a message to be received. For example:
This article related to telecommunications is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Speed_of_service |
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. More simply, the speed of sound is how fast vibrations travel. At 20 °C (68 °F), the speed of sound in air is about 343 m/s (1,125 ft/s ; 1,235 km/h ; 767 mph ; 667 kn ), or 1 km in 2.92 s or one mi... | https://en.wikipedia.org/wiki/Speed_of_sound |
Speedify is a software-based channel bonding service developed by Connectify Inc. Launched in 2014, Speedify enhances internet speed, reliability, and security by combining multiple internet connections at the same time into a single, faster, and more stable connection. It is available on various platforms, including W... | https://en.wikipedia.org/wiki/Speedify |
SpeedOf.Me is an internet speed test service which uses browser capabilities such as HTML5 and JavaScript to test the internet speed of the user. SpeedOf.Me utilizes multiple servers around the world, with the server used being chosen automatically based on location. [ 1 ] [ 2 ] It is financed through its paid API [ 3 ... | https://en.wikipedia.org/wiki/Speedof.me |
A speedometer or speed meter is a gauge that measures and displays the instantaneous speed of a vehicle. Now universally fitted to motor vehicles , they started to be available as options in the early 20th century, and as standard equipment from about 1910 onwards. [ 1 ] Other vehicles may use devices analogous to the ... | https://en.wikipedia.org/wiki/Speedometer |
The speed of sound in any chemical element in the fluid phase has one temperature-dependent value. In the solid phase , different types of sound wave may be propagated, each with its own speed: among these types of wave are longitudinal (as in fluids), transversal , and (along a surface or plate) extensional . [ 1 ]
A... | https://en.wikipedia.org/wiki/Speeds_of_sound_of_the_elements |
Speedtest.net , also known as Speedtest by Ookla , is a web service that provides free analysis of Internet access performance metrics, such as connection data rate and latency . It is the flagship product of Ookla, a web testing and network diagnostics company founded in 2006, and based in Seattle, Washington , United... | https://en.wikipedia.org/wiki/Speedtest.net |
2.1.5Isomeric SMILES
Spegatrine is an α 1 - and α 2 -adrenergic receptor antagonist isolated from Rauvolfia verticillata . Its dimer dispegatrine has greater antagonist affinity for α-adrenergic receptors . [ 1 ]
This organic chemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Spegatrine |
Speisses are alloys of heavy metals like iron, cobalt, nickel and copper [ 1 ] with arsenic, antimony and, occasionally, tin. [ 2 ] The latter elements lower the melting point to around 1000 °C. [ 2 ] Speisses commonly occur in lead smelting operations [ 3 ] and copper smelting operations. [ 2 ]
Speisses are only part... | https://en.wikipedia.org/wiki/Speiss |
Spektr-M [ 2 ] (Russian: Спектр-M) is a proposed Russian scientific satellite with a 10 m (33 ft) sub-millimeter to far infrared space telescope. It is designed to be a successor to the Herschel Space Observatory , covering similar wave bands, and to look into chemical evolution in the universe, black hole horizon radi... | https://en.wikipedia.org/wiki/Spektr-M |
Spektr-R [ 6 ] (part of RadioAstron program) ( Russian : Спектр-Р) was a Russian scientific satellite with a 10 m (33 ft) radio telescope on board. It was launched on 18 July 2011 [ 7 ] on a Zenit-3F launcher from Baikonur Cosmodrome , and was designed to perform research on the structure and dynamics of radio sources ... | https://en.wikipedia.org/wiki/Spektr-R |
Spektr-RG ( Russian : Спектр-РГ, Spectrum + Röntgen + Gamma ; also called Spectrum-X-Gamma , SRG , SXG ) is a Russian–German high-energy astrophysics space observatory which was launched on 13 July 2019. [ 4 ] It follows on from the Spektr-R satellite telescope launched in 2011. [ 5 ]
The original idea for this X-ray ... | https://en.wikipedia.org/wiki/Spektr-RG |
Spektr-UV , also known as World Space Observatory-Ultraviolet ( WSO-UV ), is a proposed ultraviolet space telescope intended for work in the 115 nm to 315 nm wavelength range. [ 3 ] [ 4 ] It is an international project led by Russia (Roscosmos), with participation from Spain and Japan. The launch had initially been pla... | https://en.wikipedia.org/wiki/Spektr-UV |
Disc and disk are both variants of the English word for objects of a generally thin and cylindrical geometry. The differences in spelling correspond both with regional differences and with different senses of the word. For example, in the case of flat, rotational data storage media the convention is that the spelling d... | https://en.wikipedia.org/wiki/Spelling_of_disc |
Spendor is a British loudspeaker manufacturing company founded in 1969 by audio engineer Spencer Hughes (1924–1983) and his wife Dorothy. [ 1 ] [ 2 ] It is located in East Sussex . [ 1 ] [ 3 ] [ 4 ] The name was derived from the first names of both. [ 4 ]
Spencer Hughes worked in an investigation team of the BBC resea... | https://en.wikipedia.org/wiki/Spendor |
Spent caustic is a waste industrial caustic solution that has become exhausted and is no longer useful (or spent). Spent caustics are made of sodium hydroxide or potassium hydroxide , water , and contaminants. The contaminants have consumed the majority of the sodium (or potassium) hydroxide and thus the caustic liquo... | https://en.wikipedia.org/wiki/Spent_caustic |
Spent shale or spent oil shale (also known as retorted shale ) is a solid residue from the shale oil extraction process of producing synthetic shale oil from oil shale . It consists of inorganic compounds ( minerals ) and remaining organic matter known as char —a carbonaceous residue formed from kerogen . Depending on ... | https://en.wikipedia.org/wiki/Spent_shale |
Sperm-mediated gene transfer (SMGT) is a transgenic technique that transfers genes based on the ability of sperm cells to spontaneously bind to and internalize exogenous DNA and transport it into an oocyte during fertilization to produce genetically modified animals . 1 Exogenous DNA refers to DNA that originates outsi... | https://en.wikipedia.org/wiki/Sperm-mediated_gene_transfer |
Sperm Chromatin Structure Assay (SCSA) is a diagnostic approach that detects sperm abnormality with a large extent of DNA fragmentation . [ 1 ] First described by Evenson in 1980, the assay is a flow cytometric test that detects the vulnerability of sperm DNA to acid-induced denaturation DNA in situ . [ 2 ] SCSA measur... | https://en.wikipedia.org/wiki/Sperm_Chromatin_Structure_Assay |
A sperm bank , semen bank, or cryobank is a facility or enterprise which purchases, stores and sells human semen . The semen is produced and sold by men who are known as sperm donors . [ 1 ] The sperm is purchased by or for other persons for the purpose of achieving a pregnancy or pregnancies other than by a sexual par... | https://en.wikipedia.org/wiki/Sperm_bank |
Sperm chemotaxis is a form of sperm guidance , in which sperm cells ( spermatozoa ) follow a concentration gradient of a chemoattractant secreted from the oocyte and thereby reach the oocyte.
Since the discovery of sperm attraction to the female gametes in ferns over a century ago, [ 1 ] sperm guidance in the form of ... | https://en.wikipedia.org/wiki/Sperm_chemotaxis |
Sperm competition is the competitive process between spermatozoa of two or more different males to fertilize the same egg [ 1 ] during sexual reproduction . Competition can occur when females have multiple potential mating partners. Greater choice and variety of mates increases a female's chance to produce more viable ... | https://en.wikipedia.org/wiki/Sperm_competition |
Sperm guidance is the process by which sperm cells ( spermatozoa ) are directed to the oocyte (egg) for the aim of fertilization . In the case of marine invertebrates the guidance is done by chemotaxis . In the case of mammals , it appears to be done by chemotaxis , thermotaxis and rheotaxis .
Since the discovery of s... | https://en.wikipedia.org/wiki/Sperm_guidance |
Sperm sorting is a means of choosing what type of sperm cell is to fertilize an egg cell using several conventional techniques of centrifugation or swim-up . Newly applied methods such as flow cytometry expand the possibilities of sperm sorting and new techniques of sperm sorting are being developed.
It can be used to... | https://en.wikipedia.org/wiki/Sperm_sorting |
Sperm thermotaxis is a form of sperm guidance, in which sperm cells (spermatozoa) actively change their swimming direction according to a temperature gradient, swimming up the gradient. Thus far this process has been discovered in mammals only.
The discovery of mammalian sperm chemotaxis and the realization that it ca... | https://en.wikipedia.org/wiki/Sperm_thermotaxis |
Spermarche , also known as semenarche , is the time at which a male experiences his first ejaculation. [ 1 ] It is considered to be the counterpart of menarche in females. [ 2 ] [ 3 ] Depending on upbringing, cultural differences, and prior sexual knowledge, males may have different reactions to spermarche, ranging fro... | https://en.wikipedia.org/wiki/Spermarche |
The spermatheca (pronounced / s p ər m ə ˈ θ iː k ə / pl. : spermathecae / s p ər m ə ˈ θ iː s iː / ), also called receptaculum seminis ( pl. : receptacula seminis ), is an organ of the female reproductive tract in insects , e.g. ants , bees , [ 1 ] some molluscs , Oligochaeta worms and certain other invertebrates and ... | https://en.wikipedia.org/wiki/Spermatheca |
Spermicide is a contraceptive substance that destroys sperm , inserted vaginally prior to intercourse to prevent pregnancy . As a contraceptive, spermicide may be used alone. However, the pregnancy rate experienced by couples using only spermicide is higher than that of couples using other methods. Usually, spermicid... | https://en.wikipedia.org/wiki/Spermicide |
Spermine synthase ( EC 2.5.1.22 , spermidine aminopropyltransferase , spermine synthetase ) is an enzyme that converts spermidine into spermine . [ 1 ] [ 2 ] This enzyme catalyses the following chemical reaction
Spermine synthase is an enzyme involved in polyamine biosynthesis. It is present in all eukaryotes and play... | https://en.wikipedia.org/wiki/Spermine_synthase |
In plant science , the spermosphere is the zone surrounding a seed where soil, microorganisms, and seed germinating interact. [ 1 ] The zone is a small area, typically 1–10 mm from the seed, but varying with seed type, the variety of soil microorganisms , the level of soil moisture, and other factors. [ 2 ]
Within the... | https://en.wikipedia.org/wiki/Spermosphere |
In mathematics , Sperner's lemma is a combinatorial result on colorings of triangulations , analogous to the Brouwer fixed point theorem , which is equivalent to it. [ 1 ] It states that every Sperner coloring (described below) of a triangulation of an n {\displaystyle n} -dimensional simplex contains a cell whose vert... | https://en.wikipedia.org/wiki/Sperner's_lemma |
Sperner's theorem , in discrete mathematics , describes the largest possible families of finite sets none of which contain any other sets in the family. It is one of the central results in extremal set theory . It is named after Emanuel Sperner , who published it in 1928.
This result is sometimes called Sperner's lem... | https://en.wikipedia.org/wiki/Sperner's_theorem |
In order-theoretic mathematics , a graded partially ordered set is said to have the Sperner property (and hence is called a Sperner poset ), if no antichain within it is larger than the largest rank level (one of the sets of elements of the same rank) in the poset. [ 1 ] Since every rank level is itself an antichain, t... | https://en.wikipedia.org/wiki/Sperner_property_of_a_partially_ordered_set |
Sphaerobacter is a genus of bacteria. When originally described it was placed in its own subclass (Spahaerobacteridae) within the class Actinomycetota . Subsequently, phylogenetic studies have now placed it in its own order Sphaerobacterales within the phylum Thermomicrobiota . [ 1 ] [ 2 ] Up to now there is only one s... | https://en.wikipedia.org/wiki/Sphaerobacter |
Sphaerotilus natans is an aquatic periphyton bacterial organism associated with polluted water. These tightly sheathed filamentous bacteria colonies are commonly but inaccurately known as " sewage fungus " [ 1 ]
Straight or smoothly curved filaments 1.5 μm in diameter and 100 to more than 500 μm in length are formed ... | https://en.wikipedia.org/wiki/Sphaerotilus_natans |
A sphere (from Greek σφαῖρα , sphaîra ) [ 1 ] is a surface analogous to the circle , a curve . In solid geometry , a sphere is the set of points that are all at the same distance r from a given point in three-dimensional space . [ 2 ] That given point is the center of the sphere, and the distance r is the sphere's radi... | https://en.wikipedia.org/wiki/Sphere |
In differential topology , sphere eversion is a theoretical process of turning a sphere inside out in a three-dimensional space (the word eversion means "turning inside out"). It is possible to smoothly and continuously turn a sphere inside out in this way (allowing self-intersections of the sphere's surface) without c... | https://en.wikipedia.org/wiki/Sphere_eversion |
In geometry, sphere packing in a cube is a three-dimensional sphere packing problem with the objective of packing spheres inside a cube . It is the three-dimensional equivalent of the circle packing in a square problem in two dimensions. The problem consists of determining the optimal packing of a given number of spher... | https://en.wikipedia.org/wiki/Sphere_packing_in_a_cube |
Sphere packing in a cylinder is a three-dimensional packing problem with the objective of packing a given number of identical spheres inside a cylinder of specified diameter and length. For cylinders with diameters on the same order of magnitude as the spheres, such packings result in what are called columnar structure... | https://en.wikipedia.org/wiki/Sphere_packing_in_a_cylinder |
In Riemannian geometry , the sphere theorem , also known as the quarter-pinched sphere theorem , strongly restricts the topology of manifolds admitting metrics with a particular curvature bound. The precise statement of the theorem is as follows. If M {\displaystyle M} is a complete , simply-connected , n -dimensional... | https://en.wikipedia.org/wiki/Sphere_theorem |
In mathematics, in the topology of 3-manifolds , the sphere theorem of Christos Papakyriakopoulos ( 1957 ) gives conditions for elements of the second homotopy group of a 3-manifold to be represented by embedded spheres.
One example is the following:
Let M {\displaystyle M} be an orientable 3-manifold such that π 2 (... | https://en.wikipedia.org/wiki/Sphere_theorem_(3-manifolds) |
The spherical Bernstein's problem is a possible generalization of the original Bernstein's problem in the field of global differential geometry , first proposed by Shiing-Shen Chern in 1969, and then later in 1970, during his plenary address at the International Congress of Mathematicians in Nice .
Are the equators in... | https://en.wikipedia.org/wiki/Spherical_Bernstein's_problem |
In organic chemistry , spherical aromaticity is formally used to describe an unusually stable nature of some spherical compounds such as fullerenes and polyhedral boranes .
In 2000, Andreas Hirsch and coworkers in Erlangen , Germany , formulated a rule to determine when a spherical compound would be aromatic . They fo... | https://en.wikipedia.org/wiki/Spherical_aromaticity |
In pure and applied mathematics , particularly quantum mechanics and computer graphics and their applications, a spherical basis is the basis used to express spherical tensors . [ definition needed ] The spherical basis closely relates to the description of angular momentum in quantum mechanics and spherical harmonic f... | https://en.wikipedia.org/wiki/Spherical_basis |
In spherical geometry , a spherical circle (often shortened to circle ) is the locus of points on a sphere at constant spherical distance (the spherical radius ) from a given point on the sphere (the pole or spherical center ). It is a curve of constant geodesic curvature relative to the sphere, analogous to a line or... | https://en.wikipedia.org/wiki/Spherical_circle |
In geometry and coding theory , a spherical code with parameters ( n , N , t ) is a set of N points on the unit hypersphere in n dimensions for which the dot product of unit vectors from the origin to any two points is less than or equal to t . The kissing number problem may be stated as the problem of finding the maxi... | https://en.wikipedia.org/wiki/Spherical_code |
The spherical cow is a humorous metaphor for highly simplified scientific models of complex phenomena. [ 1 ] [ 2 ] [ 3 ] [ 4 ] Originating in theoretical physics , the metaphor refers to some scientific tendencies to develop toy models that reduce a problem to the simplest form imaginable, making calculations more feas... | https://en.wikipedia.org/wiki/Spherical_cow |
A spherical roller bearing is a rolling-element bearing that permits rotation with low friction, and permits angular misalignment. Typically these bearings support a rotating shaft in the bore of the inner ring that may be misaligned in respect to the outer ring. The misalignment is possible due to the spherical intern... | https://en.wikipedia.org/wiki/Spherical_roller_bearing |
A spherical roller thrust bearing is a rolling-element bearing of thrust type that permits rotation with low friction , and permits angular misalignment. The bearing is designed to take radial loads, and heavy axial loads in one direction. Typically these bearings support a rotating shaft in the bore of the shaft washe... | https://en.wikipedia.org/wiki/Spherical_roller_thrust_bearing |
In geometry , a spherical sector , [ 1 ] also known as a spherical cone , [ 2 ] is a portion of a sphere or of a ball defined by a conical boundary with apex at the center of the sphere. It can be described as the union of a spherical cap and the cone formed by the center of the sphere and the base of the cap. It is th... | https://en.wikipedia.org/wiki/Spherical_sector |
In geometry , a spherical segment is the solid defined by cutting a sphere or a ball with a pair of parallel planes .
It can be thought of as a spherical cap with the top truncated, and so it corresponds to a spherical frustum .
The surface of the spherical segment (excluding the bases) is called spherical zone .
If ... | https://en.wikipedia.org/wiki/Spherical_segment |
In geometric topology , the spherical space form conjecture (now a theorem) states that a finite group acting on the 3-sphere is conjugate to a group of isometries of the 3-sphere.
The conjecture was posed by Heinz Hopf in 1926 after determining the fundamental groups of three-dimensional spherical space forms as a ge... | https://en.wikipedia.org/wiki/Spherical_space_form_conjecture |
Spherical surface acoustic wave sensors use a type of surface acoustic wave (SAW) that travels along the surface of a medium exhibiting elasticity with exponentially decaying amplitude along depth. MEMS-IDT technology allows the use of SAW waves to sense various gases. Sensitivity up to 10 ppm of hydrogen using a spher... | https://en.wikipedia.org/wiki/Spherical_surface_acoustic_wave_(SAW)_sensor |
Spherical trigonometry is the branch of spherical geometry that deals with the metrical relationships between the sides and angles of spherical triangles , traditionally expressed using trigonometric functions . On the sphere , geodesics are great circles . Spherical trigonometry is of great importance for calculations... | https://en.wikipedia.org/wiki/Spherical_trigonometry |
Spherical wave transformations leave the form of spherical waves as well as the laws of optics and electrodynamics invariant in all inertial frames . They were defined between 1908 and 1909 by Harry Bateman and Ebenezer Cunningham , with Bateman giving the transformation its name. [ M 1 ] They correspond to the conform... | https://en.wikipedia.org/wiki/Spherical_wave_transformation |
In mathematics, a field K with an absolute value is called spherically complete if the intersection of every decreasing sequence of balls (in the sense of the metric induced by the absolute value) is nonempty: [ 1 ]
The definition can be adapted also to a field K with a valuation v taking values in an arbitrary ordere... | https://en.wikipedia.org/wiki/Spherically_complete_field |
Sphericity is a measure of how closely the shape of a physical object resembles that of a perfect sphere . For example, the sphericity of the balls inside a ball bearing determines the quality of the bearing, such as the load it can bear or the speed at which it can turn without failing. Sphericity is a specific exampl... | https://en.wikipedia.org/wiki/Sphericity |
In graph theory , the sphericity of a graph is a graph invariant defined to be the smallest dimension of Euclidean space required to realize the graph as an intersection graph of unit spheres . The sphericity of a graph is a generalization of the boxicity and cubicity invariants defined by F.S. Roberts in the late 1960... | https://en.wikipedia.org/wiki/Sphericity_(graph_theory) |
Spherics (sometimes spelled sphaerics or sphaerica ) is a term used in the history of mathematics for historical works on spherical geometry , [ 1 ] [ 2 ] exemplified by the Spherics ( Ancient Greek : τὰ σφαιρικά tá sphairiká ), a treatise by the Hellenistic mathematician Theodosius (2nd or early 1st century BC), [ 3 ]... | https://en.wikipedia.org/wiki/Spherics |
In four-dimensional geometry , the spherinder , or spherical cylinder or spherical prism , is a geometric object, defined as the Cartesian product of a 3- ball (or solid 2- sphere ) of radius r 1 and a line segment of length 2 r 2 :
Like the duocylinder , it is also analogous to a cylinder in 3-space, which is the Car... | https://en.wikipedia.org/wiki/Spherinder |
The " spherium " model consists of two electrons trapped on the surface of a sphere of radius R {\displaystyle R} . It has been used by Berry and collaborators [ 1 ] to understand both weakly and strongly correlated systems and to suggest an "alternating" version of Hund's rule . Seidl studies this system in the contex... | https://en.wikipedia.org/wiki/Spherium |
A spheroplast (or sphaeroplast in British usage) is a microbial cell from which the cell wall has been almost completely removed, as by the action of penicillin or lysozyme. According to some definitions, the term is used to describe Gram-negative bacteria . [ 3 ] [ 4 ] According to other definitions, the term also enc... | https://en.wikipedia.org/wiki/Spheroplast |
In polymer physics , spherulites (from Greek sphaira = ball and lithos = stone) are spherical semicrystalline regions inside non- branched linear polymers. Their formation is associated with crystallization of polymers from the melt and is controlled by several parameters such as the number of nucleation sites, structu... | https://en.wikipedia.org/wiki/Spherulite_(polymer_physics) |
The sphincter of Boyden (also known as the choledochal sphincter ) is a sphincter located in the common bile duct before it joins with the pancreatic duct to form the ampulla of vater . This sphincter controls the flow of bile into the pancreatic duct and it helps in filling up of the gallbladder with bile .
The sphin... | https://en.wikipedia.org/wiki/Sphincter_of_Boyden |
Sphingolipids are a class of lipids containing a backbone of sphingoid bases, which are a set of aliphatic amino alcohols that includes sphingosine . They were discovered in brain extracts in the 1870s and were named after the mythological sphinx because of their enigmatic nature. [ 1 ] [ 2 ] These compounds play impo... | https://en.wikipedia.org/wiki/Sphingolipid |
Sphingosine (2-amino-4-trans-octadecene-1,3-diol) is an 18-carbon amino alcohol with an unsaturated hydrocarbon chain, which forms a primary part of sphingolipids , a class of cell membrane lipids that include sphingomyelin , an important phospholipid .
Sphingosine can be phosphorylated in vivo via two kinases , sphin... | https://en.wikipedia.org/wiki/Sphingosine |
Sphingosyl phosphatide refers to a lipid containing phosphorus and a long-chain base.
This biochemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Sphingosyl_phosphatide |
The Sphinx ( Russian : СФИНКС , romanized : SFINKS ) was an experimental Soviet project for a home automation system, commissioned by the State Committee for Science and Technology and designed by Dmitry Azrikan , in collaboration with A. Kolotushkin and V. Goessen, in 1987. [ 1 ] Sphinx, an acronym for Super Functiona... | https://en.wikipedia.org/wiki/Sphinx_(home_automation_system) |
Spice , spiciness , or spicity , symbol τ , is a term in oceanography referring to variations in the temperature and salinity of seawater over space or time, whose combined effects leave the water's density unchanged. For a given spice, any change in temperature is offset by a change in salinity to maintain unchanged... | https://en.wikipedia.org/wiki/Spice_(oceanography) |
SpiderCloud Wireless [ 1 ] was founded in November 2006 as Evoke Networks by Peter Wexler, Allan Baw, and Mark Gallagher. The trio incubated the company as Copivia Inc. and hired Mike Gallagher as CEO in October 2007. After closing the Series-A funding in January 2008, the company soon changed its name to SpiderCloud W... | https://en.wikipedia.org/wiki/SpiderCloud_Wireless |
Spider is a balloon-borne experiment designed to search for primordial gravitational waves imprinted on the cosmic microwave background (CMB). Measuring the strength of this signal puts limits on inflationary theory .
The Spider instrument consists of six degree-resolution telescopes cooled to liquid Helium temperatu... | https://en.wikipedia.org/wiki/Spider_(polarimeter) |
Spider silk is a protein fibre or silk spun by spiders . Spiders use silk to make webs or other structures that function as adhesive traps to catch prey, to entangle and restrain prey before biting, to transmit tactile information, or as nests or cocoons to protect their offspring. They can use the silk to suspend them... | https://en.wikipedia.org/wiki/Spider_silk |
Spike-in controls or spike-ins are known quantities of molecules—such as oligonucleotide sequences (RNA, DNA), proteins , or metabolites —added to a biological sample for more accurate quantitative estimation of the molecule of interest across samples and batches. [ 1 ] Spike-ins are particularly used in high-throughpu... | https://en.wikipedia.org/wiki/Spike-in_controls |
The spike response model (SRM) [ 1 ] is a spiking neuron model in which spikes are generated by either a deterministic [ 2 ] or a stochastic [ 1 ] threshold process. In the SRM, the membrane voltage V is described as a linear sum of the postsynaptic potentials (PSPs) caused by spike arrivals to which the effects of ref... | https://en.wikipedia.org/wiki/Spike_response_model |
A spike strip (also referred to as a spike belt , road spikes , traffic spikes , tire shredders , stingers , stop sticks , by the trademark Stinger or formally known as a Tire Deflation Device or TDD ) is a device or incident weapon used to impede or stop the movement of wheeled vehicles by puncturing their tires .
Ge... | https://en.wikipedia.org/wiki/Spike_strip |
Spiling is a traditional technique used in temperate regions of the world for the prevention of erosion to river and stream banks.
Willow spiling is currently used in the United Kingdom; live willow rods are woven between live willow uprights and the area behind is filled with soil for the willow to root into. [ 1 ]
... | https://en.wikipedia.org/wiki/Spiling |
Spill kits are typically single-use kits containing chemicals used for absorption of ( hazardous ) wastes. Ready-for-use kits typically contain personal protective equipment , decontamination or neutralizing agents, disposal containers, and signage markers. Sometimes, spill containment material will also be included.
... | https://en.wikipedia.org/wiki/Spill_kit |
A spill metric is a heuristic metric used by register allocators to decide which registers to spill. Popular spill metrics are:
Where cost is the estimated cost of spilling a value from registers into memory.
This computing article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Spill_metric |
Spillover infection , also known as pathogen spillover and spillover event , occurs when a reservoir population with a high pathogen prevalence comes into contact with a novel host population. The pathogen is transmitted from the reservoir population and may or may not be transmitted within the host population. [ 1 ] D... | https://en.wikipedia.org/wiki/Spillover_infection |
In quantum mechanics , spin-exchange is an interaction process between two particles mediated by an exchange interaction . [ 1 ] It preserves total angular momentum of the system but may allow other aspects of the system to change. When two spin-polarized atoms in their ground state experience a spin-exchange collision... | https://en.wikipedia.org/wiki/Spin-exchange |
In chemistry , reactions that involve a change in spin state are known as spin-forbidden reactions Such reactions show increased activation energy when compared to a similar reaction in which the spin states of the reactant and product are isomorphic. As a result of this increased activation energy, a decreased rate of... | https://en.wikipedia.org/wiki/Spin-forbidden_reactions |
Spin-polarized electron energy loss spectroscopy or SPEELS is a technique mainly used to measure the dispersion relation of the collective excitations, over the whole Brillouin zone .
Spin waves are collective perturbations in a magnetic solid. Their properties depend on their wavelength (or wave vector ). For long wa... | https://en.wikipedia.org/wiki/Spin-polarized_electron_energy_loss_spectroscopy |
Spin is an intrinsic form of angular momentum carried by elementary particles , and thus by composite particles such as hadrons , atomic nuclei , and atoms. [ 1 ] [ 2 ] : 183 –184 Spin is quantized, and accurate models for the interaction with spin require relativistic quantum mechanics or quantum field theory .
The e... | https://en.wikipedia.org/wiki/Spin_(physics) |
The spin Hall effect (SHE) is a transport phenomenon predicted by Russian physicists Mikhail I. Dyakonov and Vladimir I. Perel in 1971. [ 1 ] [ 2 ] It consists of the appearance of spin accumulation on the lateral surfaces of an electric current -carrying sample, the signs of the spin directions being opposite on the o... | https://en.wikipedia.org/wiki/Spin_Hall_effect |
The spin Nernst effect is a phenomenon of spin current generation caused by the thermal flow of electrons or magnons in condensed matter. Under a thermal drive such as temperature gradient or chemical potential gradient, spin-up and spin-down carriers can flow perpendicularly to the thermal current and towards opposite... | https://en.wikipedia.org/wiki/Spin_Nernst_Effect |
The spin angular momentum of light ( SAM ) is the component of angular momentum of light that is associated with the quantum spin and the rotation between the polarization degrees of freedom of the photon.
Spin is the fundamental property that distinguishes the two types of elementary particles: fermions , with half-i... | https://en.wikipedia.org/wiki/Spin_angular_momentum_of_light |
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