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Spontaneous emission is the process in which a quantum mechanical system (such as a molecule , an atom or a subatomic particle ) transits from an excited energy state to a lower energy state (e.g., its ground state ) and emits a quantized amount of energy in the form of a photon . Spontaneous emission is ultimately res... | https://en.wikipedia.org/wiki/Spontaneous_emission |
Spontaneous fission (SF) is a form of radioactive decay in which a heavy atomic nucleus splits into two or more lighter nuclei. In contrast to induced fission , there is no inciting particle to trigger the decay; it is a purely probabilistic process.
Spontaneous fission is a dominant decay mode for superheavy elements... | https://en.wikipedia.org/wiki/Spontaneous_fission |
Tempered or toughened glass is a type of safety glass processed by controlled thermal or chemical treatments to increase its strength compared with normal glass. Tempering puts the outer surfaces into compression and the interior into tension . Such stresses cause the glass, when broken, to shatter into small granular ... | https://en.wikipedia.org/wiki/Spontaneous_glass_breakage |
Spontaneous human combustion ( SHC ) is the pseudoscientific [ 1 ] concept of the spontaneous combustion of a living (or recently deceased) human body without an apparent external source of ignition on the body. In addition to reported cases, descriptions of the alleged phenomenon appear in literature, and both types h... | https://en.wikipedia.org/wiki/Spontaneous_human_combustion |
In thermodynamics , a spontaneous process is a process which occurs without any external input to the system. A more technical definition is the time-evolution of a system in which it releases free energy and it moves to a lower, more thermodynamically stable energy state (closer to thermodynamic equilibrium ). [ 1 ] [... | https://en.wikipedia.org/wiki/Spontaneous_process |
Spontaneous symmetry breaking is a spontaneous process of symmetry breaking , by which a physical system in a symmetric state spontaneously ends up in an asymmetric state. [ 1 ] [ 2 ] [ 3 ] In particular, it can describe systems where the equations of motion or the Lagrangian obey symmetries, but the lowest-energy vacu... | https://en.wikipedia.org/wiki/Spontaneous_symmetry_breaking |
In solid state physics , spontelectrics is the study and phenomenon of thin films of various materials producing strong electric fields .
When laid down as thin films tens to hundreds of molecular layers thick, a range of materials spontaneously generate large electric fields . The electric fields can be greater than ... | https://en.wikipedia.org/wiki/Spontelectrics |
Spoof surface plasmons , also known as spoof surface plasmon polaritons and designer surface plasmons , [ 1 ] are surface electromagnetic waves in microwave and terahertz regimes that propagate along planar interfaces with sign-changing permittivities . Spoof surface plasmons are a type of surface plasmon polariton , w... | https://en.wikipedia.org/wiki/Spoof_surface_plasmon |
A spoolbase is a shore-based facility used to facilitate continuous pipe laying for offshore oil and gas production . [ 1 ] The facility allows the welding of single or double joints (40' or 80') of steel pipe of 4" to 18" diameter, into predetermined lengths for spooling onto a reel lay vessel .
Shore based spoolbase... | https://en.wikipedia.org/wiki/Spoolbase |
In the mathematical classification of finite simple groups , there are a number of groups which do not fit into any infinite family. These are called the sporadic simple groups , or the sporadic finite groups , or just the sporadic groups .
A simple group is a group G that does not have any normal subgroups except for... | https://en.wikipedia.org/wiki/Sporadic_group |
In biology , a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. [ 1 ] Spores form part of the life cycles of many plants , algae , fungi and protozoa . [ 2 ] They were thought to have appeared... | https://en.wikipedia.org/wiki/Spore |
The sporocarp (also known as fruiting body , fruit body or fruitbody ) of fungi is a multicellular structure on which spore-producing structures , such as basidia or asci , are borne. The fruitbody is part of the sexual phase of a fungal life cycle , [ 1 ] while the rest of the life cycle is characterized by vegetative... | https://en.wikipedia.org/wiki/Sporocarp_(fungus) |
Sporogenesis is the production of spores in biology . The term is also used to refer to the process of reproduction via spores. Reproductive spores were found to be formed in eukaryotic organisms, such as plants , algae and fungi , during their normal reproductive life cycle . Dormant spores are formed, for example by ... | https://en.wikipedia.org/wiki/Sporogenesis |
Sporoplasm is an infectious material present in the cytoplasm of various fungi -like organisms, such as members of class Microsporidia . Sporoplasm is defined as a mass of protoplasm that gives rise to or forms a spore. The protoplasmic body that is released as an infective amoebula from a cnidosporidian cyst . [ 1 ]
... | https://en.wikipedia.org/wiki/Sporoplasm |
Sporopollenin is a biological polymer found as a major component of the tough outer (exine) walls of plant spores and pollen grains. It is chemically very stable (one of the most inert among biopolymers) [ 1 ] and is usually well preserved in soils and sediments . The exine layer is often intricately sculptured in spec... | https://en.wikipedia.org/wiki/Sporopollenin |
Sporosarcina pasteurii formerly known as Bacillus pasteurii from older taxonomies , is a gram positive bacterium with the ability to precipitate calcite and solidify sand given a calcium source and urea ; through the process of microbiologically induced calcite precipitation (MICP) or biological cementation . [ 2 ] S. ... | https://en.wikipedia.org/wiki/Sporosarcina_pasteurii |
Sports engineering is a sub-discipline of engineering that applies math and science to develop technology, equipment, and other resources as they pertain to sport.
Sports engineering was first introduced by Isaac Newton ’s observation of a tennis ball. [ 1 ] In the mid-twentieth century, Howard Head became one of the ... | https://en.wikipedia.org/wiki/Sports_engineering |
Spot analysis , spot test analysis , or a spot test is a chemical test , a simple and efficient technique where analytic assays are executed in only one, or a few drops, of a chemical solution, preferably in a great piece of filter paper, without using any sophisticated instrumentation. The development and popularizati... | https://en.wikipedia.org/wiki/Spot_analysis |
In combinatorial game theory , the Sprague–Grundy theorem states that every impartial game under the normal play convention is equivalent to a one-heap game of nim , or to an infinite generalization of nim. It can therefore be represented as a natural number , the size of the heap in its equivalent game of nim, as an o... | https://en.wikipedia.org/wiki/Sprague–Grundy_theorem |
A spray pond is a reservoir in which warmed water (e.g. from a power plant ) is cooled before reuse by spraying the warm water with nozzles into the cooler air . Cooling takes place by exchange of heat with the ambient air, involving both conductive heat transfer between the water droplets and the surrounding air and e... | https://en.wikipedia.org/wiki/Spray_pond |
A spray tower (or spray column or spray chamber ) is a gas-liquid contactor used to achieve mass and heat transfer between a continuous gas phase (that can contain dispersed solid particles) and a dispersed liquid phase. It consists of an empty cylindrical vessel made of steel or plastic, and nozzles that spray liquid ... | https://en.wikipedia.org/wiki/Spray_tower |
Divine Proportions: Rational Trigonometry to Universal Geometry is a 2005 book by the mathematician Norman J. Wildberger on a proposed alternative approach to Euclidean geometry and trigonometry , called rational trigonometry . The book advocates replacing the usual basic quantities of trigonometry, Euclidean distance... | https://en.wikipedia.org/wiki/Spread_(rational_trigonometry) |
In mathematics , and more specifically matrix theory , the spread of a matrix is the largest distance in the complex plane between any two eigenvalues of the matrix.
Let A {\displaystyle A} be a square matrix with eigenvalues λ 1 , … , λ n {\displaystyle \lambda _{1},\ldots ,\lambda _{n}} . That is, these values λ i {... | https://en.wikipedia.org/wiki/Spread_of_a_matrix |
Spreaders in mining are heavy equipment used in surface mining and mechanical engineering/civil engineering. The primary function of a spreader is to act as a continuous spreading machine in large-scale open pit mining operations.
A Spreader's superstructure may be seen as superficially similar to that of a bucket-whe... | https://en.wikipedia.org/wiki/Spreader_(mining) |
A spring is a natural exit point at which groundwater emerges from an aquifer and flows across the ground surface as surface water . It is a component of the hydrosphere , as well as a part of the water cycle . Springs have long been important for humans as a source of fresh water , especially in arid regions which hav... | https://en.wikipedia.org/wiki/Spring_(hydrology) |
The spring bloom is a strong increase in phytoplankton abundance (i.e. stock) that typically occurs in the early spring and lasts until late spring or early summer. This seasonal event is characteristic of temperate North Atlantic, sub-polar, and coastal waters. [ 1 ] [ 2 ] Phytoplankton blooms occur when growth exceed... | https://en.wikipedia.org/wiki/Spring_bloom |
Sprinkler fitting is a skilled trade that consists of assembling, installing, testing, repairing, inspecting, and certifying automatic fire suppression systems and their associated piping in commercial, industrial and residential buildings. [ 1 ] [ 2 ]
Sprinkler systems installed by sprinkler fitters can include the u... | https://en.wikipedia.org/wiki/Sprinkler_fitting |
A spur or track in radiation chemistry is a region of high concentration of chemical products after ionizing radiation passes through. The spur model , proposed by Samuel and Magee in 1953, describes the kinetic behavior of reaction spurs involving one type of radicals in a diffusion -driven environment. [ 1 ] The spur... | https://en.wikipedia.org/wiki/Spur_(chemistry) |
In statistics , a spurious relationship or spurious correlation [ 1 ] [ 2 ] is a mathematical relationship in which two or more events or variables are associated but not causally related , due to either coincidence or the presence of a certain third, unseen factor (referred to as a "common response variable", "confoun... | https://en.wikipedia.org/wiki/Spurious_relationship |
In electronics ( radio in particular), a spurious tone (also known as an interfering tone , a continuous tone or a spur ) denotes a tone in an electronic circuit which interferes with a signal and is often masked underneath that signal. Spurious tones are any tones other than a fundamental tone or its harmonics . [ 1 ]... | https://en.wikipedia.org/wiki/Spurious_tone |
Spurious trip level (STL) is defined as a discrete level for specifying the spurious trip requirements of safety functions to be allocated to safety systems. An STL of 1 means that this safety function has the highest level of spurious trips. The higher the STL level the lower the number of spurious trips caused by the... | https://en.wikipedia.org/wiki/Spurious_trip_level |
Sputnik 1 EMC/EMI is a class of full-scale laboratory models of the Soviet Sputnik 1 satellite, made to test ground Electromagnetic Compatibility (EMC) and Electromagnetic Interference (EMI). The models, manufactured by OKB-1 and NII-885 (headed by Mikhail Ryazansky), were introduced on February 15, 1957. [ 1 ]
The fi... | https://en.wikipedia.org/wiki/Sputnik-1_EMC/EMI_lab_model |
In physics, sputtering is a phenomenon in which microscopic particles of a solid material are ejected from its surface, after the material is itself bombarded by energetic particles of a plasma or gas . [ 2 ] It occurs naturally in outer space , and can be an unwelcome source of wear in precision components. However, t... | https://en.wikipedia.org/wiki/Sputtering |
Squalene is an organic compound . It is a triterpene with the formula C 30 H 50 . It is a colourless oil, although impure samples appear yellow. It was originally obtained from shark liver oil (hence its name, as Squalus is a genus of sharks). An estimated 12% of bodily squalene in humans is found in sebum . [ 5 ] Squa... | https://en.wikipedia.org/wiki/Squalene |
A squamulose lichen is a lichen that is composed of small, often overlapping "scales" called squamules . [ 1 ] If they are raised from the substrate and appear leafy, the lichen may appear to be a foliose lichen , but the underside does not have a "skin" ( cortex ), as foliose lichens do. [ 2 ] Squamulose lichens are c... | https://en.wikipedia.org/wiki/Squamulose_lichen |
Within the area of organocatalysis , squaramide catalysis describes the use of squaramides to accelerate and stereochemically alter organic transformations. The effects arise through hydrogen-bonding interactions between the substrate and the squaramide, unlike classic catalysts, and is thus a type of hydrogen-bond ca... | https://en.wikipedia.org/wiki/Squaramide_catalysis |
In mathematics , a square-free integer (or squarefree integer ) is an integer which is divisible by no square number other than 1. That is, its prime factorization has exactly one factor for each prime that appears in it. For example, 10 = 2 ⋅ 5 is square-free, but 18 = 2 ⋅ 3 ⋅ 3 is not, because 18 is divisible by 9 = ... | https://en.wikipedia.org/wiki/Square-free_integer |
In mathematics , a square-free polynomial is a univariate polynomial (over a field or an integral domain ) that has no multiple root in an algebraically closed field containing its coefficients. In characteristic 0, or over a finite field , a univariate polynomial is square free if and only if it does not have as a div... | https://en.wikipedia.org/wiki/Square-free_polynomial |
In mathematics , a square-integrable function , also called a quadratically integrable function or L 2 {\displaystyle L^{2}} function or square-summable function , [ 1 ] is a real - or complex -valued measurable function for which the integral of the square of the absolute value is finite. Thus, square-integrability on... | https://en.wikipedia.org/wiki/Square-integrable_function |
In mathematics , a square is the result of multiplying a number by itself. The verb "to square" is used to denote this operation. Squaring is the same as raising to the power 2 , and is denoted by a superscript 2; for instance, the square of 3 may be written as 3 2 , which is the number 9.
In some cases when superscrip... | https://en.wikipedia.org/wiki/Square_(algebra) |
In chemistry , the square antiprismatic molecular geometry describes the shape of compounds where eight atoms , groups of atoms, or ligands are arranged around a central atom, defining the vertices of a square antiprism . [ 1 ] This shape has D 4d symmetry and is one of the three common shapes for octacoordinate transi... | https://en.wikipedia.org/wiki/Square_antiprismatic_molecular_geometry |
In mathematics, specifically abstract algebra , a square class of a field F {\displaystyle F} is an element of the square class group , the quotient group F × / F × 2 {\displaystyle F^{\times }/F^{\times 2}} of the multiplicative group of nonzero elements in the field modulo the square elements of the field. Each squar... | https://en.wikipedia.org/wiki/Square_class |
In statistical mechanics , the two-dimensional square lattice Ising model is a simple lattice model of interacting magnetic spins . The model is notable for having nontrivial interactions, yet having an analytical solution . The model was solved by Lars Onsager for the special case that the external magnetic field H = ... | https://en.wikipedia.org/wiki/Square_lattice_Ising_model |
In term logic (a branch of philosophical logic ), the square of opposition is a diagram representing the relations between the four basic categorical propositions .
The origin of the square can be traced back to Aristotle 's tractate On Interpretation and its distinction between two oppositions: contradiction and contr... | https://en.wikipedia.org/wiki/Square_of_opposition |
In chemistry , the square planar molecular geometry describes the stereochemistry (spatial arrangement of atoms) that is adopted by certain chemical compounds . As the name suggests, molecules of this geometry have their atoms positioned at the corners.
Numerous compounds adopt this geometry, examples being especially... | https://en.wikipedia.org/wiki/Square_planar_molecular_geometry |
Square pyramidal geometry describes the shape of certain chemical compounds with the formula ML 5 where L is a ligand . If the ligand atoms were connected, the resulting shape would be that of a pyramid with a square base . The point group symmetry involved is of type C 4v . The geometry is common for certain main gro... | https://en.wikipedia.org/wiki/Square_pyramidal_molecular_geometry |
The square root of 2 (approximately 1.4142) is the positive real number that, when multiplied by itself or squared, equals the number 2 . It may be written as 2 {\displaystyle {\sqrt {2}}} or 2 1 / 2 {\displaystyle 2^{1/2}} . It is an algebraic number , and therefore not a transcendental number . Technically, it should... | https://en.wikipedia.org/wiki/Square_root_of_2 |
The square root of 3 is the positive real number that, when multiplied by itself, gives the number 3 . It is denoted mathematically as 3 {\textstyle {\sqrt {3}}} or 3 1 / 2 {\displaystyle 3^{1/2}} . It is more precisely called the principal square root of 3 to distinguish it from the negative number with the same prope... | https://en.wikipedia.org/wiki/Square_root_of_3 |
The square root of 5 is the positive real number that, when multiplied by itself, gives the prime number 5 . It is more precisely called the principal square root of 5 , to distinguish it from the negative number with the same property. This number appears in the fractional expression for the golden ratio . It can be d... | https://en.wikipedia.org/wiki/Square_root_of_5 |
The square root of 6 is the positive real number that, when multiplied by itself, gives the natural number 6 . It is more precisely called the principal square root of 6 , to distinguish it from the negative number with the same property. This number appears in numerous geometric and number-theoretic contexts. It can b... | https://en.wikipedia.org/wiki/Square_root_of_6 |
The square root of 7 is the positive real number that, when multiplied by itself, gives the prime number 7 . It is more precisely called the principal square root of 7 , to distinguish it from the negative number with the same property. This number appears in various geometric and number-theoretic contexts. It can be d... | https://en.wikipedia.org/wiki/Square_root_of_7 |
Philip Deidesheimer was a mining engineer in the Western United States .
Deidesheimer was born in 1832, in Darmstadt , Electorate of Hesse before German unification. He attended the prestigious Freiberg University of Mining ( Technische Universität Bergakademie Freiberg ) and emigrated to California in 1852. He died o... | https://en.wikipedia.org/wiki/Square_set_timbering |
In geometry , a square trisection is a type of dissection problem which consists of cutting a square into pieces that can be rearranged to form three identical squares.
The dissection of a square in three congruent partitions is a geometrical problem that dates back to the Islamic Golden Age . Craftsman who mastered t... | https://en.wikipedia.org/wiki/Square_trisection |
In number theory , the sum of the first n cubes is the square of the n th triangular number . That is,
The same equation may be written more compactly using the mathematical notation for summation :
This identity is sometimes called Nicomachus's theorem , after Nicomachus of Gerasa ( c. 60 – c. 120 CE ).
Nicomachus,... | https://en.wikipedia.org/wiki/Squared_triangular_number |
The square–cube law (or cube–square law ) is a mathematical principle, applied in a variety of scientific fields, which describes the relationship between the volume and the surface area as a shape's size increases or decreases. It was first [ dubious – discuss ] described in 1638 by Galileo Galilei in his Two New Scie... | https://en.wikipedia.org/wiki/Square–cube_law |
The Squarial (a portmanteau of the words square and aerial ) was a satellite antenna used for reception of the now defunct British Satellite Broadcasting television service (BSB). The Squarial was a flat plate satellite antenna, built to be unobtrusive and unique. BSB were counting on the form factor of the antenna to ... | https://en.wikipedia.org/wiki/Squarial |
Squaring the square is the problem of tiling an integral square using only other integral squares. (An integral square is a square whose sides have integer length.) The name was coined in a humorous analogy with squaring the circle . Squaring the square is an easy task unless additional conditions are set. The most st... | https://en.wikipedia.org/wiki/Squaring_the_square |
The squat effect is the hydrodynamic phenomenon by which a vessel moving through shallow water creates an area of reduced pressure that causes the ship to increase its draft (alternatively decrease the underkeel clearance of the vessel in marine terms) and thereby be closer to the seabed than would otherwise be expect... | https://en.wikipedia.org/wiki/Squat_effect |
Squawk is a Java micro edition virtual machine for embedded system and small devices. Most virtual machines for the Java platform are written in low level native languages such as C / C++ and assembler ; what makes Squawk different is that Squawk's core is mostly written in Java (this is called a meta-circular interpre... | https://en.wikipedia.org/wiki/Squawk_virtual_machine |
Squeeze flow (also called squeezing flow, squeezing film flow, or squeeze flow theory) is a type of flow in which a material is pressed out or deformed between two parallel plates or objects. First explored in 1874 by Josef Stefan , [ 1 ] squeeze flow describes the outward movement of a droplet of material, its area of... | https://en.wikipedia.org/wiki/Squeeze_flow |
Squeeze job , [ 1 ] or squeeze cementing is a term often used in the oilfield to describe the process of injecting cement slurry into a zone, generally for pressure-isolation purposes. [ 2 ]
The term probably originated from the concept that enough water is "squeezed" out of the slurry to render it unflowable, so the ... | https://en.wikipedia.org/wiki/Squeeze_job |
In linear algebra , a squeeze mapping , also called a squeeze transformation , is a type of linear map that preserves Euclidean area of regions in the Cartesian plane , but is not a rotation or shear mapping .
For a fixed positive real number a , the mapping
is the squeeze mapping with parameter a . Since
is a hyper... | https://en.wikipedia.org/wiki/Squeeze_mapping |
In calculus , the squeeze theorem (also known as the sandwich theorem , among other names [ a ] ) is a theorem regarding the limit of a function that is bounded between two other functions.
The squeeze theorem is used in calculus and mathematical analysis , typically to confirm the limit of a function via comparison w... | https://en.wikipedia.org/wiki/Squeeze_theorem |
In telecommunications , squelch is a circuit function that acts to suppress the audio (or video ) output of a receiver in the absence of a strong input signal . [ 1 ] Essentially, squelch is a specialized type of noise gate designed to suppress weak signals. Squelch is used in two-way radios and VHF/UHF radio scanners ... | https://en.wikipedia.org/wiki/Squelch |
Squelching is a biological phenomenon in which a strong transcriptional activator acts to inhibit the expression of another gene . [ 1 ] Squelching has been mostly studied in yeast, and most of the ideas regarding its mechanisms have come from research into modes of transcriptional control in yeast. [ 2 ] One important... | https://en.wikipedia.org/wiki/Squelching |
Squigonometry or p -trigonometry is a generalization of traditional trigonometry which replaces the circle and Euclidean distance function with the squircle (shape intermediate between a square and circle) and p -norm . While trigonometry deals with the relationships between angles and lengths in the plane using trigon... | https://en.wikipedia.org/wiki/Squigonometry |
In fluid dynamics , Squire's theorem states that of all the perturbations that may be applied to a shear flow (i.e. a velocity field of the form U = ( U ( z ) , 0 , 0 ) {\displaystyle \mathbf {U} =(U(z),0,0)} ), the perturbations which are least stable are two-dimensional, i.e. of the form u ′ = ( u ′ ( x , z , t ) , 0... | https://en.wikipedia.org/wiki/Squire's_theorem |
The squirmer is a model for a spherical microswimmer swimming in Stokes flow . The squirmer model was introduced by James Lighthill in 1952 and refined and used to model Paramecium by John Blake in 1971. [ 1 ] [ 2 ] Blake used the squirmer model to describe the flow generated by a carpet of beating short filaments call... | https://en.wikipedia.org/wiki/Squirmer |
Strontium nitrate is an inorganic compound composed of the elements strontium , nitrogen and oxygen with the formula Sr ( NO 3 ) 2 . This colorless solid is used as a red colorant and oxidizer in pyrotechnics .
Strontium nitrate is typically generated by the reaction of nitric acid on strontium carbonate . [ 2 ]
Lik... | https://en.wikipedia.org/wiki/Sr(NO3)2 |
Strontium hydroxide , Sr(OH) 2 , is a caustic alkali composed of one strontium ion and two hydroxide ions. It is synthesized by combining a strontium salt with a strong base . Sr(OH) 2 exists in anhydrous , monohydrate , or octahydrate form.
Because Sr(OH) 2 is slightly soluble in cold water, its preparation can be e... | https://en.wikipedia.org/wiki/Sr(OH)2 |
Distrontium ruthenate , also known as strontium ruthenate , is an oxide of strontium and ruthenium with the chemical formula Sr 2 RuO 4 . It was the first reported perovskite superconductor that did not contain copper . Strontium ruthenate is structurally very similar to the high-temperature cuprate superconductors, ... | https://en.wikipedia.org/wiki/Sr2RuO4 |
Strontium nitride , Sr 3 N 2 , is produced by burning strontium metal in air (resulting in a mixture with strontium oxide ) or in nitrogen . Like other metal nitrides , it reacts with water to give strontium hydroxide and ammonia:
This inorganic compound –related article is a stub . You can help Wikipedia by expanding... | https://en.wikipedia.org/wiki/Sr3N2 |
Strontium bromide is a chemical compound with a formula Sr Br 2 . At room temperature it is a white, odourless, crystalline powder. Strontium bromide imparts a bright red colour in a flame test , showing the presence of strontium ions. It is used in flares and also has some pharmaceutical uses.
SrBr 2 can be prepared ... | https://en.wikipedia.org/wiki/SrBr2 |
Strontium chloride (SrCl 2 ) is a salt of strontium and chloride . It is a "typical" salt, forming neutral aqueous solutions. As with all compounds of strontium, this salt emits a bright red colour in flame, and is commonly used in fireworks to that effect. [ citation needed ] Its properties are intermediate between th... | https://en.wikipedia.org/wiki/SrCl2 |
Strontium fluoride , SrF 2 , also called strontium difluoride and strontium(II) fluoride , is a fluoride of strontium . It is a brittle white crystalline solid. In nature, it appears as the very rare mineral strontiofluorite . [ 2 ] [ 3 ]
Strontium fluoride is prepared by the action of hydrofluoric acid on strontium c... | https://en.wikipedia.org/wiki/SrF2 |
Strontium iodide is an inorganic compound with the chemical formula Sr I 2 . It is a salt of strontium and iodine . It forms a hexahydrate SrI 2 ·6H 2 O . It is an ionic, water-soluble, and deliquescent compound that can be used in medicine as a substitute for potassium iodide . [ 5 ] It is also used as a scintillation... | https://en.wikipedia.org/wiki/SrI2 |
Strontium oxide or strontia , SrO, is formed when strontium reacts with oxygen . Burning strontium in air results in a mixture of strontium oxide and strontium nitride . It also forms from the decomposition of strontium carbonate SrCO 3 . It is a strongly basic oxide.
About 8% by weight of cathode-ray tubes is stronti... | https://en.wikipedia.org/wiki/SrO |
Strontium peroxide is an inorganic compound with the formula Sr O 2 that exists in both anhydrous and octahydrate form, both of which are white solids. The anhydrous form adopts a structure similar to that of calcium carbide . [ 4 ] [ 5 ]
It is an oxidizing agent used for bleaching . It is used in some pyrotechnic co... | https://en.wikipedia.org/wiki/SrO2 |
Monostrontium ruthenate is the inorganic compound with the formula SrRuO 3 . It is one of two main strontium ruthenates , the other having the formula Sr 2 RuO 4 . SrRuO 3 is a ferromagnetic. [ 1 ] It has a perovskite structure as do many complex metal oxides with the ABO 3 formula. The Ru 4+ ions occupy the octahed... | https://en.wikipedia.org/wiki/SrRuO3 |
Strontium sulfide is the inorganic compound with the formula Sr S . It is a white solid. The compound is an intermediate in the conversion of strontium sulfate, the main strontium ore called celestite (or, more correctly, celestine), to other more useful compounds. [ 2 ] [ 3 ] [ 4 ]
Strontium sulfide is produced by r... | https://en.wikipedia.org/wiki/SrS |
Strontium sulfate (SrSO 4 ) is the sulfate salt of strontium . It is a white crystalline powder and occurs in nature as the mineral celestine . It is poorly soluble in water to the extent of 1 part in 8,800. It is more soluble in dilute HCl and nitric acid and appreciably soluble in alkali chloride solutions (e.g. sodi... | https://en.wikipedia.org/wiki/SrSO4 |
Tausonite
Strontium titanate is an oxide of strontium and titanium with the chemical formula Sr Ti O 3 . At room temperature, it is a centrosymmetric paraelectric material with a perovskite structure. At low temperatures it approaches a ferroelectric phase transition with a very large dielectric constant ~10 4 but rem... | https://en.wikipedia.org/wiki/SrTiO3 |
Srinivasan Chandrasekaran (born 1945) is an Indian organic and organometallic chemist , academic and a former chair of the Department of Organic Chemistry and the Division of Chemical Sciences. He was also a former Dean of the Faculty of Science at the Indian Institute of Science . He was known for his research on orga... | https://en.wikipedia.org/wiki/Srinivasan_Chandrasekaran |
In coding theory , Srivastava codes , formulated by Professor J. N. Srivastava , form a class of parameterised error-correcting codes which are a special case of alternant codes .
The original Srivastava code over GF( q ) of length n is defined by a parity check matrix H of alternant form
where the α i and z i are e... | https://en.wikipedia.org/wiki/Srivastava_code |
The St. Petersburg paradox or St. Petersburg lottery [ 1 ] is a paradox involving the game of flipping a coin where the expected payoff of the lottery game is infinite but nevertheless seems to be worth only a very small amount to the participants. The St. Petersburg paradox is a situation where a naïve decision criter... | https://en.wikipedia.org/wiki/St._Petersburg_paradox |
stICQ is an ICQ client for mobile phones with symbian OS.
StICQ was written by the Russian programmer Sergey Taldykin. StICQ is a native Symbian application (.SIS) for instant messaging over Internet for the ICQ network (using the OSCAR protocol ).
It supports all main statuses including "Not Available", "Invisible" ... | https://en.wikipedia.org/wiki/StICQ |
Staballoy is the name of two different classes of metal alloys, one class typically used for munitions and a different class developed for drilling rods.
In a military context, staballoys are metal alloys of a high proportion of depleted uranium with other metals, usually titanium or molybdenum , designed for use in k... | https://en.wikipedia.org/wiki/Staballoy |
In coordination chemistry , a stability constant (also called formation constant or binding constant ) is an equilibrium constant for the formation of a complex in solution. It is a measure of the strength of the interaction between the reagents that come together to form the complex . There are two main kinds of compl... | https://en.wikipedia.org/wiki/Stability_constants_of_complexes |
In mathematics , the stability radius of an object (system, function , matrix , parameter ) at a given nominal point is the radius of the largest ball , centered at the nominal point, all of whose elements satisfy pre-determined stability conditions. The picture of this intuitive notion is this:
where p ^ {\display... | https://en.wikipedia.org/wiki/Stability_radius |
In model theory , a branch of mathematical logic , a complete first-order theory T is called stable in λ (an infinite cardinal number ), if the Stone space of every model of T of size ≤ λ has itself size ≤ λ. T is called a stable theory if there is no upper bound for the cardinals κ such that T is stable in κ. The stab... | https://en.wikipedia.org/wiki/Stability_spectrum |
In civil engineering , stabilization is the retrofitting of platforms or foundations as constructed for the purpose of improving the bearing capacity and levelness of the supported building.
Soil failure can occur on a slope, a slope failure or landslide , or in a flat area due to liquefaction of water-saturated sand a... | https://en.wikipedia.org/wiki/Stabilization_(architecture) |
A stabilized liquid membrane device or SLMD is a type of passive sampling device which allows for the in situ , integrative collection of waterborne, labile ionic metal contaminants. [ 1 ] By capturing and sequestering metal ions onto its surface continuously over a period of days to weeks, an SLMD can provide an integ... | https://en.wikipedia.org/wiki/Stabilized_liquid_membrane_device |
A stabilized soil mixing plant is a combination of kinds of machines used for mixing stabilized soil , which is used for highway construction , municipal road projects, and fertile airport areas. The plant produces stabilized soil with different gradings in a continuous way. Such a plant usually contains a cement silo ... | https://en.wikipedia.org/wiki/Stabilized_soil_mixing_plant |
In industrial chemistry , a stabilizer or stabiliser is a chemical that is used to prevent degradation . [ 1 ] Above all, heat and light stabilizers are added to plastic and rubber materials because they ensure safe processing and protect products against aging and weathering. In particular polyvinyl chloride would not... | https://en.wikipedia.org/wiki/Stabilizer_(chemistry) |
In quantum computing and quantum communication , a stabilizer code is a class of quantum codes for performing quantum error correction . The toric code , and surface codes more generally, [ 1 ] are types of stabilizer codes considered very important for the practical realization of quantum information processing.
Qua... | https://en.wikipedia.org/wiki/Stabilizer_code |
Stabilizing selection (not to be confused with negative or purifying selection [ 1 ] [ 2 ] ) is a type of natural selection in which the population mean stabilizes on a particular non-extreme trait value. This is thought to be the most common mechanism of action for natural selection because most traits do not appear t... | https://en.wikipedia.org/wiki/Stabilizing_selection |
Stable-isotope probing ( SIP ) is a technique in microbial ecology for tracing uptake of nutrients in biogeochemical cycling by microorganisms. A substrate is enriched with a heavier stable isotope that is consumed by the organisms to be studied. [ 1 ] [ 2 ] Biomarkers with the heavier isotopes incorporated into them c... | https://en.wikipedia.org/wiki/Stable-isotope_probing |
Stable stratification of fluids occurs when each layer is less dense than the one below it. Unstable stratification is when each layer is denser than the one below it.
Buoyancy forces tend to preserve stable stratification; the higher layers float on the lower ones. In unstable stratification, on the other hand, buoya... | https://en.wikipedia.org/wiki/Stable_and_unstable_stratification |
In cellular biology , stable cells are cells that multiply only when needed. They spend most of the time in the quiescent G 0 phase of the cell cycle but can be stimulated to enter the cell cycle when needed. Examples include the liver , the proximal tubules of the kidney and endocrine glands .
This cell biology artic... | https://en.wikipedia.org/wiki/Stable_cell |
In model theory , a stable group is a group that is stable in the sense of stability theory .
An important class of examples is provided by groups of finite Morley rank (see below).
The Cherlin–Zilber conjecture (also called the algebraicity conjecture ), due to Gregory Cherlin (1979) and Boris Zil'ber (1977) , sugge... | https://en.wikipedia.org/wiki/Stable_group |
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