Chemistry terminology · MLC-0109

Chemistry terms: S (1,437)

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• Size-exclusion chromatographyA chromatographic technique used to separate macromolecules, such as polymers, based primarily on their...
• Sjögren syndromeA chronic autoimmune disease characterized by the immune system attacking moisture-producing glands...
• Skeletal atomAn atom that forms part of the main chain or backbone of a polymer molecule, excluding atoms in pendant...
• Skeletal bondA covalent bond connecting two skeletal atoms within the main chain or backbone of a polymer molecule. These...
• Skeletal fluorosisA chronic bone disease caused by excessive intake of fluoride, leading to abnormal bone formation and...
• Skeletal formulaA simplified representation of an organic molecule that shows the carbon skeleton and functional groups...
• Skeletal structureThe arrangement of the main chain atoms, or skeletal atoms, that form the continuous backbone of a polymer...
• SkimmerA conical or plate-like electrode with a central orifice, used in mass spectrometry and other vacuum systems...
• SkinThe outermost protective organ of the body, composed of multiple layers, primarily the epidermis, dermis, and...
• Skin immune systemThe network of cells and soluble factors within the skin that provides a defense against pathogens and...
• Skin sensitization testAn experimental procedure designed to identify substances that can induce an allergic contact dermatitis...
• Skin testA diagnostic procedure involving the introduction of a small amount of an allergen or antigen into or onto...
• Slater determinantA mathematical expression used in quantum mechanics to describe the wave function of a multi-electron system...
• Slater-type orbitalAn atomic orbital function whose radial part has the form r^(n-1) exp(-ζr), with the exponent ζ fixed by the...
• SlimicideA chemical agent used to control or prevent the growth of slime-forming microorganisms, such as bacteria...
• SlipA fluid suspension of fine solid particles in a liquid, prepared for use in ceramic processing or as a...
• Slip castingA forming process used to create ceramic or polymer-based objects by pouring a liquid suspension, known as a...
• Slit widthThe physical dimension of the opening that defines the spectral bandwidth of radiation passing through a...
• Slope factorA quantitative measure of the carcinogenic potential of a chemical, derived from the slope of the...
• Slow coagulation rateThe rate at which colloidal particles aggregate in a dispersion when the repulsive forces between them are...
• Slow coagulation rate coefficientA quantitative measure of the rate at which colloidal particles aggregate in a dispersion under conditions...
• Slow neutronsNeutrons whose kinetic energy lies below a specified value, which varies with the application. In reactor...
• Slow-reacting substance of anaphylaxisA mixture of leukotrienes, primarily LTC4, LTD4, and LTE4, released from mast cells and other immune cells...
• SLUDDEAn acronym representing a collection of symptoms associated with cholinergic overstimulation, typically...
• SluggingA process in pharmaceutical manufacturing where a powder blend is compressed into large, un-uniform tablets...
• Small G proteinA family of monomeric guanine nucleotide-binding proteins that act as molecular switches in intracellular...
• Small inhibitory double-stranded RNAA synthetic or endogenously produced double-stranded RNA molecule, typically 20-25 nucleotides in length...
• Small interfering RNA moleculeA class of short, double-stranded ribonucleic acid (RNA) molecules involved in the process of RNA...
• Small moleculeA molecule of low relative molecular mass whose structure is not composed of multiple repeating...
• Small outer capsid proteinA small accessory protein of about 9 kDa, called Soc, that decorates the outside of the bacteriophage T4 head...
• Small particleA particle in a polymer solution whose largest dimension is considerably smaller than the wavelength of the...
• Small-angle X-ray scatteringA non-destructive analytical technique that probes the structure of materials at the nanoscale by analyzing...
• SMARTSA language for describing molecular patterns, similar to SMILES but designed for substructure searching...
• SmecticDescribing a liquid-crystal state, or mesophase, in which the constituent molecules exhibit both...
• Smectic mesophaseA liquid crystalline state where molecules are organized into well-defined layers, exhibiting one-dimensional...
• SM-interferenceAn interference in which a foreign substance S gives a signal by a mechanism similar to that of the analyte...
• SMIRKSA line notation for representing generic chemical reactions, which allows for the specification of atom and...
• SmogA visible air pollution haze whose name blends smoke and fog. Classical London-type smog comes from coal...
• Smog chamberA large, enclosed environmental chamber used to simulate and study the chemical and physical processes that...
• Smog indexA numerical value that quantifies the severity of air pollution, particularly photochemical smog, in a given...
• SmokeAn aerosol of solid particles or liquid droplets suspended in a gas, formed from incomplete combustion or...
• SmoothingA data processing technique applied to analytical signals to reduce random noise and highlight underlying...
• SoapA salt of a fatty acid, typically an alkali metal salt, used as a cleaning agent. These compounds possess...
• Soap curdA precipitate formed when soap, an alkali metal salt of a fatty acid, reacts with hard water ions such as...
• Soap filmA thin layer of liquid, typically water, stabilized by surfactant molecules, such as soap, that reduce the...
• Social interaction testA behavioral assay used in neurotoxicology and pharmacology to assess the effects of substances on social...
• Societal riskThe risk of multiple fatalities or injuries occurring simultaneously as a result of a single hazardous event...
• Soft bakeA low-temperature heating step applied to a photoresist film after coating and before exposure, designed to...
• Soft independent modelling of class analogyA supervised classification method in chemometrics that builds a separate principal component analysis (PCA)...
• Soft ionizationAn ionization technique in mass spectrometry that imparts minimal internal energy to the analyte molecules...
• Soft lithographyA family of microfabrication techniques that use elastomeric stamps, molds, or masks to pattern surfaces...
• Soft-segment phase domainA distinct region within a block copolymer or segmented polymer where the more flexible, lower glass...
• SoilThe unconsolidated mineral or organic material on the immediate surface of the Earth that serves as a natural...
• Soil partition coefficientThe ratio of the concentration of a chemical adsorbed to soil particles to its concentration in the soil pore...
• SoilingThe deposition of particulate matter, such as dust, soot, or aerosols, onto surfaces, leading to...
• SolA type of colloidal dispersion in which solid particles are suspended in a continuous liquid medium. The...
• Sol fractionThe portion of a polymer sample that remains soluble after a crosslinking reaction or gelation process. This...
• Solar cellA device that converts light energy directly into electrical energy through the photovoltaic effect. It...
• Solar conversion efficiencyThe ratio of the electrical power or chemical energy produced by a solar energy conversion device to the...
• Solar flareA sudden, intense brightening observed over the Sun's surface, representing a large energy release of up to 6...
• Solar radiationElectromagnetic radiation emitted by the Sun, encompassing a broad spectrum from ultraviolet to infrared...
• Sol-gel coatingA thin film applied to a substrate using the sol-gel process, involving the deposition of a liquid precursor...
• Sol-gel critical concentrationThe threshold concentration of added salt beyond which a sol of particles coagulates into aggregates rather...
• Sol-gel materialA material formed through the sol-gel process, which involves the hydrolysis and condensation of molecular...
• Sol-gel metal oxideA metal oxide material synthesized via the sol-gel process, where metal alkoxides or inorganic metal salts...
• Sol-gel processA chemical process used to produce solid materials from small molecules, typically involving the hydrolysis...
• Sol-gel silicaA form of silica prepared through the sol-gel process, involving the hydrolysis and condensation of silicon...
• Sol-gel transitionThe point at which a colloidal suspension (sol) transforms into a continuous, interconnected network (gel)...
• Solid amalgam electrodeAn electrode constructed from a solid alloy of a metal, such as gold or silver, with mercury. This type of...
• Solid angleA measure of the extent of a cone-like region in three-dimensional space, subtended by an object at a point...
• Solid angle of analyserThe angular range over which an electron or ion energy analyzer collects particles emitted from a sample...
• Solid dispersionA system in which at least one active ingredient is dispersed in an inert carrier or matrix in the solid...
• Solid phase antibody radioimmunoassayA type of radioimmunoassay where antibodies are immobilized onto a solid support, such as the inner surface...
• Solid polymer electrolyteA solvent-free polymer material containing dissolved salts that exhibits ionic conductivity. It consists of a...
• Solid state lasersLasers that use a solid material as the gain medium, typically a crystalline or glass host doped with active...
• Solid supportAn inert, insoluble material that provides a stationary phase for chemical reactions or separations...
• Solid volumeThe physical space occupied by the solid components within a porous material or a chromatographic column. It...
• SolidificationThe phase transition of a substance from a liquid or gaseous state to a solid state, typically involving the...
• Solidification modelA picture of a semicrystalline polymer that crystallizes from the melt as lamellae, with one macromolecule...
• Solidified floating organic dropA microextraction technique where a small drop of an organic solvent, which is liquid at room temperature but...
• Solidified floating organic drop microextractionA microextraction technique where a small volume of an organic solvent, which is liquid at room temperature...
• Solid-phase dynamic extractionA variant of solid-phase microextraction in which the sorbent coating lines the inside wall of a hollow...
• Solid-phase extractionA sample preparation technique that uses a solid sorbent to isolate analytes from a liquid sample matrix. The...
• Solid-phase microextractionA solvent-free sample preparation technique that uses a fused silica fiber coated with an extracting phase to...
• Solids contentThe proportion of non-volatile material remaining after the volatile components, such as solvents or water...
• Solid-state nuclear magnetic resonance spectroscopyA spectroscopic technique that applies nuclear magnetic resonance principles to study the structure and...
• Solid-state polymerisationA polymerization of a crystalline monomer carried out in the solid state, without melting or dissolving it...
• SolidusA curve in a phase diagram that represents the temperatures at which a given mixture of chemical components...
• SolitonA self-reinforcing solitary wave packet that maintains its shape while propagating at a constant velocity...
• Solonitsyn effectAn effect in which adsorption of a gas, or a reaction of it, on a photocatalyst takes place after the solid...
• SolubilisationThe process by which a substance, which is otherwise insoluble in a given solvent, is brought into solution...
• Solubilising agentsSubstances added to a formulation to increase the solubility of a poorly soluble compound in a given solvent...
• SolubilityThe maximum amount of a substance (solute) that can dissolve in a given amount of solvent at a specific...
• Solubility constantAn equilibrium constant that extends the solubility product to cases where the dissolved solute also includes...
• Solubility parameterA numerical value that quantifies the cohesive energy density of a material, providing an estimate of its...
• SoluteA substance that is dissolved in another substance, known as the solvent, to form a solution. The solute is...
• Solute-volatilization interferenceAn interference in flame atomic spectrometry in which a concomitant substance changes how fast the dry...
• SolutionA homogeneous mixture composed of two or more substances, where one substance (the solute) is uniformly...
• SolvateA crystalline adduct formed between a solute and solvent molecules, where the solvent molecules are...
• SolvationThe process by which solvent molecules surround and interact with solute molecules or ions, forming a...
• Solvation energyThe change in Gibbs energy when a solute is transferred from the gas phase into a solvent, representing the...
• Solvatochromic relationshipA quantitative correlation between a spectroscopic property, such as the absorption or emission maximum of a...
• SolvatochromismThe phenomenon where the color or spectral properties (e.g., absorption or emission maxima) of a chemical...
• SolvatomersIsomers of a solute that differ only in the arrangement of the solvent molecules around it, that is, in their...
• SolventA liquid substance, or a mixture of liquids, capable of dissolving other substances (solutes) to form a...
• Solvent abuseThe intentional inhalation of volatile organic solvents or other psychoactive substances to achieve...
• Solvent blank flux densityThe radiant power per unit area that passes through the atomizer in an atomic absorption spectroscopy setup...
• Solvent desorptionThe process of removing an adsorbed substance from a sorbent material by washing it with a suitable solvent...
• Solvent dragThe movement of a solute across a semipermeable membrane due to the bulk flow of the solvent, rather than by...
• Solvent extractionA method for separating components of a mixture based on their differential solubilities between two...
• Solvent frontThe front line of the eluent in planar chromatography, marking the farthest point the mobile phase has...
• Solvent isotope effectThe change in the rate or equilibrium constant of a chemical reaction when a solvent containing normal...
• Solvent migration-distanceThe distance traveled by the mobile phase from the point of application or origin along the stationary phase...
• Solvent mole fractionThe mole fraction of one solvent component calculated on the basis of the solvent constituents only, that is...
• Solvent nucleationThe recondensation of solvent vapour onto solid particles or droplets carried in an aerosol. In sample...
• Solvent parameterA numerical value that quantifies a specific property of a solvent, such as its polarity, hydrogen-bond...
• Solvent shiftA change in the position of an absorption or emission band in a spectrum, typically observed in...
• Solvent suppressionA technique employed in nuclear magnetic resonance (NMR) spectroscopy to reduce or eliminate the signal...
• Solvent transport rateThe mass of solvent, both as liquid and as vapour, that reaches an inductively coupled plasma in a given...
• Solvent vapor annealingA post-processing technique used to induce self-assembly or crystallization in polymer thin films by exposing...
• Solvent volume fractionThe share of one solvent in a solvent mixture when the solutes are left out of the count, found by dividing...
• Solvent-induced symmetry breakingThe loss of molecular symmetry caused by interactions with a polar solvent, which polarizes the charge...
• SolvolysisA type of nucleophilic substitution or elimination reaction where the solvent molecule acts as the...
• SolvophilicDescribing a substance or a part of a molecule that has an affinity for a particular solvent. This affinity...
• SolvophobicDescribing a substance or a part of a molecule that repels or has a low affinity for a particular solvent...
• Solvophobicity parameterA solvent parameter that rates how strongly a solvent promotes solvophobic effects, defined as one minus the...
• SolvusA curve on a phase diagram that delineates the boundary of a single-phase solid solution field from a region...
• SomaticRelating to the non-reproductive cells of an organism, encompassing all body cells except for germ cells...
• Somatic deathThe irreversible cessation of all vital functions of the entire organism, including respiration, circulation...
• Somatic diversification theoryA concept explaining the generation of antibody diversity in B lymphocytes through genetic recombination...
• Somatic gene conversionA non-reciprocal transfer of genetic information from one DNA sequence to another homologous sequence within...
• Somatic hypermutationA cellular process that introduces point mutations into the variable regions of immunoglobulin genes in B...
• Somatic recombinationThe genetic rearrangement process in developing lymphocytes that assembles functional genes for...
• Somatic riskThe probability of an adverse health effect occurring in an exposed individual during their lifetime...
• SomatomedinA group of peptide hormones, primarily insulin-like growth factors (IGF-1 and IGF-2), that mediate the...
• SomatotropinA peptide hormone produced and secreted by the anterior pituitary gland, responsible for stimulating growth...
• SomiteOne of a series of segmented blocks of mesoderm that form along the neural tube of vertebrate embryos. These...
• SOMOAn acronym for Singly Occupied Molecular Orbital, which is a molecular orbital containing a single unpaired...
• Sonic hedgehogA secreted protein that functions as a morphogen, a signaling molecule that directs the development of...
• Sonic spray ionizationA soft ionization technique used in mass spectrometry where a liquid sample is nebulized into a fine aerosol...
• SonicationThe process of applying sound energy, typically in the ultrasonic range, to agitate particles in a sample...
• SonogelA gel formed through the application of ultrasound, which promotes the aggregation of particles or molecules...
• SonoluminescenceThe emission of light from cavitation bubbles in a liquid that are excited by sound waves. As these bubbles...
• Sonophotocatalytic reactorA device designed to carry out chemical reactions that are simultaneously initiated or enhanced by both...
• SonosolA colloidal suspension (sol) prepared or modified through the application of ultrasound (sonication). The...
• SootA finely divided, black, carbonaceous material produced by the incomplete combustion of organic matter, such...
• SoporificA substance that causes or induces a state of drowsiness or sleep. These agents act on the central nervous...
• SorbateA substance that is taken up by another material through the process of sorption. This uptake can occur via...
• Sorbent trapA device containing a sorbent material designed to capture and concentrate specific analytes from a gas or...
• Sorbent-containing pipette tipA pipette tip that incorporates a small amount of sorbent material within its structure, used for micro-scale...
• SorptionA general physicochemical process by which one substance takes up or holds another, used when the specific...
• Sorption constantA quantitative measure of the equilibrium distribution of a chemical between a sorbent phase and a solution...
• Sorption isothermA graphical representation showing the relationship between the amount of a substance sorbed by a material...
• Sorptive insertionA surface reaction in which a gaseous molecule inserts directly into the bond between the surface and an...
• Sorptive-tape extractionA microextraction technique where a flexible, sorbent-coated tape is exposed to a sample, allowing analytes...
• Source termA mathematical expression used in transport models to describe the rate at which a pollutant is released into...
• Southern blotA molecular biology technique used to detect specific DNA sequences in DNA samples. DNA fragments, separated...
• Soxhlet extractionA laboratory technique for the continuous extraction of compounds from a solid sample into a solvent. The...
• Space chargeA net electrical charge within a volume of a material, arising from an imbalance of positive and negative...
• Space charge effectA phenomenon in mass spectrometry where the accumulation of ions in a confined region, such as an ion trap...
• Space charge regionA region within a semiconductor or electrolyte where there is a net electrical charge due to an imbalance of...
• Space formulaA drawing that shows the spatial arrangement of the bonds around atoms, a synonym of stereochemical formula...
• Space timeA measure of the average residence time of fluid in a continuous flow reactor, defined as the ratio of the...
• Space velocityA measure of the rate at which a fluid passes through a reactor or over a catalyst bed, expressed as the...
• SpacerA flexible, non-mesogenic segment within a polymer chain that separates and connects mesogenic groups or side...
• Spacer armA chemical chain of atoms that connects a ligand or other moiety to a polymer backbone or substrate...
• Spare receptorReceptors that exist in excess of the number required to elicit a maximal biological response when activated...
• Spark ionizationAn ionization technique used in mass spectrometry where a high-voltage spark is discharged between two...
• SpasmolyticA drug that relieves spasm of smooth muscle, for example in the gut, bile ducts, or urinary tract, typically...
• SpasticDescribing a state of increased muscle tone, often accompanied by exaggerated reflexes and involuntary muscle...
• SpasticityA motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes, resulting in...
• Spatial-distribution interferenceAn interference in flame atomic spectrometry in which a concomitant changes the way the analyte species move...
• Spatially offset Raman spectroscopyA variant of Raman spectroscopy that acquires spectral information from subsurface layers of a sample by...
• Spatially resolving detectorA type of detector capable of determining the position of incident radiation or particles across a...
• SpawnThe act of releasing gametes, such as eggs or sperm, into an external environment, particularly by aquatic...
• SpawningThe act of releasing eggs and sperm (gametes) by aquatic animals, referring to the process rather than the...
• Spearman-Karber methodA nonparametric procedure for estimating the median lethal or effective dose from quantal dose-response data...
• Special salt effectAn observation in solvolysis reactions where the addition of certain salts, particularly lithium perchlorate...
• SpeciationThe way a given element is divided among its distinct chemical forms in a sample or system, whether those...
• Speciation analysisAnalytical work aimed at identifying individual chemical forms of an element in a sample and determining how...
• SpeciesA basic rank of biological classification, a taxonomic subdivision of a genus made up of closely related...
• Species assemblageA collection of different species coexisting within a defined area or habitat at a particular time. This...
• Species differences in sensitivityThe variation in the response of different species when exposed to the same concentration of a specific...
• Species diversityA measure of the variety of different species within a given ecological community or region. It encompasses...
• Species evennessA measure of the relative abundance of different species within a community. High evenness indicates that all...
• Species imbalanceA state within an ecosystem where the relative proportions or populations of different species deviate...
• Species richnessThe number of different species present in a particular ecological community or area. This metric is a...
• Species sensitivity distributionA statistical distribution that describes the variation in sensitivity of different species to a particular...
• Species-area relationshipThe empirical relationship describing how the number of species found in a habitat (species richness)...
• Species-deletion stabilityThe tendency of a modelled ecological community to settle at a locally stable equilibrium among its surviving...
• Species-specific sensitivityThe inherent susceptibility of a particular species to a toxic substance or environmental stressor, which is...
• SpecificAn adjective placed before the name of an extensive quantity to show that it has been divided by mass, as in...
• Specific absorption coefficientA measure of how strongly a substance absorbs light at a particular wavelength, normalized by its...
• Specific acid-base catalysisA type of acid-base catalysis where the reaction rate is dependent only on the concentration of the solvated...
• Specific action conceptA working assumption in radiotracer studies that a radioactive isotope of an element behaves exactly like the...
• Specific activityThe activity of a radionuclide per unit mass of an element, or per unit mass of a chemical compound...
• Specific activity (radionuclide), see Specific activity
• Specific adsorptionThe adsorption of ions at an interface through short-range forces in addition to Coulomb attraction, such as...
• Specific bindingThe reversible interaction between a ligand and a macromolecule, such as a protein or nucleic acid, that...
• Specific burn-upThe amount of energy released per unit mass of nuclear fuel during its operation in a nuclear reactor. It...
• Specific catalysisA type of catalysis where the reaction rate is directly proportional to the concentration of a specific acid...
• Specific death rateA death rate calculated for a subgroup of a population defined by a shared attribute such as age, sex, or...
• Specific detectorA detector in chromatography that responds selectively to certain chemical or physical properties of the...
• Specific heat capacityThe amount of heat energy required to raise the temperature of a unit mass of a substance by one degree...
• Specific ionizationThe number of ion pairs produced by an ionizing particle per unit path length in a given medium. This value...
• Specific napierian attenuance coefficientA measure of the attenuance of a substance per unit mass concentration and per unit path length, using the...
• Specific napierian scattering coefficientA measure of the scattering of light by a substance per unit mass concentration and per unit path length...
• Specific pathogen freeDescribing laboratory animals that are certified to be free from a defined list of microorganisms and...
• Specific permeabilityA quantity that characterizes how an empty tube or packed column resists the flow of the mobile phase...
• Specific photoadsorption numberA quantitative measure of the amount of a substance adsorbed onto a photocatalyst surface per unit mass of...
• Specific pore volumeThe total volume of pores within a material per unit mass of that material. It provides an indication of the...
• Specific resolutionA measure of the ability of a separation system to distinguish between two closely eluting components...
• Specific surface areaThe total surface area of a material per unit of its mass or volume. It quantifies the extent of the exposed...
• Specific volumeThe quotient of a substance's volume divided by its mass, representing the volume occupied by a unit mass of...
• Specifically absorbing ionAn ion that adsorbs onto a surface through chemical interactions or strong electrostatic forces, even against...
• Specifically labelledDescribing a chemical compound in which the position of an isotopic label is precisely known and indicated...
• Specifically labelled tracerA tracer molecule in which a specific atom or group of atoms has been replaced by an isotope, either...
• SpecificityA performance measure of a two-class classification model, such as a QSAR predictor of toxicity, giving the...
• Specified requirementA documented need or expectation for a product, process, or service, often established by customers...
• SpecimenA portion deliberately drawn from a changing system, such as a flowing stream or a blood draw, that is taken...
• Spectator holeA vacancy created in an inner-shell electron orbital of an atom during an ionization process, which does not...
• Spectator mechanismA pre-association mechanism in which a second species is already held in an encounter pair with the substrate...
• Spectator-stripping reactionAn extreme form of stripping reaction in a molecular collision, in which one product leaves with nearly the...
• Spectral bandA continuous range of wavelengths or frequencies within an electromagnetic spectrum, often associated with...
• Spectral bandwidthThe range of wavelengths or frequencies that are passed by a monochromator or filter, or that are effectively...
• Spectral bandwidth errorThe deviation in absorbance or transmittance measurements caused by the finite width of the spectral band...
• Spectral distributionThe relative amount of radiant energy or power as a function of wavelength or frequency for a given light...
• Spectral effectivenessThe relative ability of different wavelengths of light to induce a specific photochemical or photobiological...
• Spectral fluenceThe radiant energy per unit area at a specific wavelength or within a narrow wavelength interval, incident on...
• Spectral fluence rateThe radiant power per unit area at a specific wavelength or within a narrow wavelength interval, incident on...
• Spectral interferenceAn effect in spectrochemical analysis where the analytical signal from an analyte overlaps with a signal from...
• Spectral irradianceThe radiant power incident on a surface per unit area, per unit wavelength interval. It quantifies the...
• Spectral lineA narrow, distinct peak or trough in a spectrum that corresponds to a specific wavelength or frequency of...
• Spectral overlapThe extent to which the emission spectrum of a light-emitting chemical entity (the donor) overlaps with the...
• Spectral photon exitanceThe number of photons emitted from a surface per unit area, per unit time, per unit wavelength interval. This...
• Spectral photon flowThe number of photons per unit time, per unit wavelength interval, emitted from a source or passing through a...
• Spectral photon fluxThe number of photons incident on a surface per unit area, per unit time, per unit wavelength interval. This...
• Spectral photon irradianceThe radiant flux of photons incident on a surface per unit area, per unit wavelength interval. It describes...
• Spectral photon radianceThe number of photons emitted or reflected from a surface per unit area, per unit solid angle, per unit time...
• Spectral photonic yieldThe ratio of the rate of a specific photochemical or photophysical process to the rate of incident photons at...
• Spectral quantitiesPhysical quantities that describe the distribution of radiant energy or power as a function of wavelength...
• Spectral quantum yieldThe ratio of the number of specific photophysical or photochemical events occurring to the number of photons...
• Spectral radianceThe radiant power emitted or reflected from a surface per unit area, per unit solid angle, per unit...
• Spectral radiant energyThe radiant energy at a specific wavelength or within a small wavelength interval, per unit wavelength...
• Spectral radiant energy densityThe radiant energy per unit volume per unit interval of wavelength or frequency, describing the concentration...
• Spectral radiant exitanceThe radiant power emitted from a point on a surface, per unit area of that surface and per unit wavelength...
• Spectral radiant fluxThe radiant flux at a specific wavelength or within a small wavelength interval, per unit wavelength...
• Spectral radiant intensityThe radiant power emitted by a point source per unit solid angle, per unit wavelength interval. This quantity...
• Spectral radiant powerThe radiant power per unit interval of wavelength, frequency, or wavenumber. It quantifies the rate at which...
• Spectral rangeThe span of wavelengths or frequencies over which a spectrometer or other optical instrument is designed to...
• Spectral responsivityThe ratio of the output signal of a detector to the incident radiant power, as a function of wavelength. This...
• Spectral sensitivityThe response of a photodetector or other light-sensitive system as a function of the wavelength of the...
• Spectral sensitizationThe process of extending the spectral range of a photographic emulsion or other light-sensitive material to...
• Spectral skewingA distortion of the relative peak intensities in a mass spectrum that arises when the concentrations of the...
• Spectral spheradianceThe radiant flux of photons arriving at a specific point from all directions, per unit of spherical surface...
• Spectral subtractionA computational technique used to remove the contribution of an interfering component from a measured...
• Spectral widthThe span of frequencies covered by the window in which signals of one nucleus type are recorded in an NMR...
• Spectrochemical bufferA substance added to a sample and reference materials in spectrochemical analysis to reduce or eliminate...
• Spectrochemical carrierA substance added to a sample for arc or spark emission analysis that produces a gas or vapour, which sweeps...
• SpectroelectrochemistryA hybrid analytical technique that combines electrochemical methods with spectroscopic methods to study the...
• SpectrogramA photographic or other permanent record of a spectrum, displaying the intensity of radiation as a function...
• SpectrographAn optical instrument that disperses electromagnetic radiation into its constituent wavelengths and records...
• SpectrometerAn instrument that measures the intensity of electromagnetic radiation as a function of its wavelength or...
• Spectrometer response functionA curve describing how efficiently a spectrometer registers particles, equal to the count of particles...
• Spectrometer transmission functionThe fraction of particles, such as electrons or ions, that a spectrometer analyser lets through compared with...
• SpectroscopeAn optical instrument used for visually observing the spectral components of light. It disperses light into...
• SpectroscopyThe study of the interaction between matter and electromagnetic radiation as a function of the radiation's...
• SpectrumA display or plot of the intensity of electromagnetic radiation or other physical quantity as a function of...
• Spectrum analysisThe reading of an energy spectrum to extract the energies and intensities of the radiation present. Peak...
• Specular reflectanceThe ratio of the radiant power reflected from a surface in a mirror-like fashion to the total radiant power...
• Specular reflectionThe mirror-like reflection of radiation from a smooth surface, in which the reflected ray lies in the plane...
• Specular X-ray reflectrometryA surface-sensitive analytical technique that measures the intensity of X-rays reflected from a surface at an...
• SpeedThe magnitude of the velocity of a particle or body, representing the rate of change of its position without...
• Speed distribution functionA mathematical function that describes the probability of finding particles in a system with a particular...
• Speed of light in a vacuumThe constant physical speed at which all electromagnetic radiation, including light, propagates through a...
• Spemann organizerA cluster of cells located in the dorsal lip of the blastopore during the early amphibian gastrula stage of...
• SpermThe male reproductive cell, a haploid motile gamete with a head holding the nucleus, a midpiece rich in...
• Sperm motilityThe ability of spermatozoa to move under their own power, with progressive motility meaning travel forward in...
• SpermatidA haploid male germ cell that results from the meiotic division of a secondary spermatocyte. These cells...
• SpermatocideA chemical substance that kills spermatozoa, the mature male gametes, thereby preventing fertilization. These...
• SpermatogenesisThe complete developmental process by which spermatogonia, the diploid germ-line stem cells of the testis...
• Spermatogonial chromosome aberration testAn in vivo genotoxicity assay in which rodents are dosed with a test substance and spermatogonia are later...
• SpermatogoniumA diploid germ line stem cell located in the seminiferous tubules of the testes, capable of self-renewal and...
• SpermatozoonThe mature, motile male gamete, or sperm cell, which is responsible for fertilizing the female gamete (ovum)...
• SpermiationThe process by which mature spermatozoa are released from the Sertoli cells into the lumen of the...
• SpermiogenesisThe final stage of spermatogenesis, during which a round, haploid spermatid undergoes a profound...
• Sphenoid boneA complex, butterfly-shaped bone located at the base of the skull, anterior to the temporal bones and basilar...
• SpherandA synthetic macrocyclic ligand characterized by a preorganized, rigid three-dimensional cavity designed to...
• Spherical carbonaceous mesophaseMicroscopic, anisotropic liquid crystalline spheres that form during the carbonization of pitches and tars at...
• Spherical radianceA radiometric quantity equal to the radiant exitance: the radiant power leaving a source, summed over all...
• Spherical radiant exposureThe time integral of spherical irradiance, representing the total radiant energy incident on a small sphere...
• Spherical topA nonlinear molecule possessing three equal principal moments of inertia, meaning its rotational properties...
• SpheronisationA pharmaceutical manufacturing process used to produce spherical particles, or pellets, from a wet mass of...
• SpheruliteA spherical, semicrystalline microstructure that forms in many polymers upon cooling from the melt or during...
• SphincterA circular muscle that surrounds an orifice or passage, controlling its opening and closing by contraction...
• SphingolipidA lipid built on a sphingoid base, a long-chain aliphatic amino alcohol such as sphingosine, usually with a...
• Sphingolipids, see Sphingolipid
• SphingomyelinA phospholipid of the sphingolipid family made of ceramide, a sphingosine joined to a fatty acid, with a...
• SphingosineAn unsaturated amino alcohol containing an 18-carbon aliphatic chain, which serves as a primary structural...
• SpikeThe addition of a known amount of an analyte to a sample matrix to assess analytical recovery or to calibrate...
• Spiked bioassay approachA sediment toxicity testing design in which clean sediment is spiked with a graded series of toxicant...
• Spillover hypothesisA hypothesis that a toxic metal causes damage only after its concentration exceeds the capacity of...
• SpinAn intrinsic angular momentum of elementary particles, such as electrons and atomic nuclei, which gives rise...
• Spin conservation ruleA principle stating that the total spin angular momentum of a system must remain unchanged during a chemical...
• Spin contaminationThe mixing of different spin states in a quantum mechanical wavefunction that is intended to represent a pure...
• Spin crossoverA phenomenon observed in certain transition metal complexes where the spin state of the metal ion changes...
• Spin decouplingA technique in nuclear magnetic resonance (NMR) spectroscopy where the spin-spin coupling between specific...
• Spin densityThe net electron spin angular momentum per unit volume at a particular point in a molecule or material. It...
• Spin echoA nuclear magnetic resonance (NMR) phenomenon where a transient signal is generated by refocusing the...
• Spin labelA stable free radical, typically a nitroxide, that is covalently attached to a molecule of interest to...
• Spin polarizationThe phenomenon where the electron spins in a molecule or radical are not randomly oriented but exhibit a...
• Spin projectionA mathematical procedure used in quantum chemistry to remove spin contamination from a wavefunction that is...
• Spin systemA collection of interacting nuclear spins within a molecule that are coupled through scalar (J) or dipolar...
• Spin trappingA technique used to detect and identify highly reactive free radicals by reacting them with a diamagnetic...
• Spina bifidaA congenital birth defect characterized by the incomplete closing of the neural tube during early embryonic...
• Spinal columnThe vertebral column, a flexible bony structure extending from the base of the skull to the pelvis, composed...
• Spinal cordA long, cylindrical bundle of nerve fibers and associated tissue extending from the brainstem down through...
• Spin-allowed electronic transitionAn electronic transition between two states that have the same total spin angular momentum. According to the...
• Spin-flip methodA quantum chemical approach used to describe electronic states that differ by a single spin flip...
• Spin-flip transitionA transition between electronic states of a molecule or ion that involves a change in the total electron spin...
• Spin-glass transitionA magnetic phase transition where a disordered magnetic system enters a state characterized by randomly...
• Spin-lattice relaxationThe process by which a system of nuclear spins in a magnetic field returns to thermal equilibrium with its...
• Spin-lattice relaxation timeThe characteristic time constant for the return of the nuclear spin system to thermal equilibrium with its...
• Spinning sidebandsSatellite lines in a solid-state NMR spectrum recorded with magic angle spinning, appearing on both sides of...
• SpinodalA boundary on a phase diagram that delineates the region where a single-phase system becomes...
• Spinodal decompositionA phase separation mechanism in which a homogeneous solution spontaneously separates into two or more...
• Spin-orbit couplingThe interaction between the intrinsic angular momentum (spin) of an electron and its orbital angular...
• Spin-orbit coupling constantA parameter that quantifies the strength of the interaction between the intrinsic angular momentum (spin) of...
• Spin-orbit splittingThe energy difference between electronic states that arise from the interaction of an electron's spin angular...
• spin-Peierls transitionA phase transition occurring in one-dimensional antiferromagnetic spin chains, where the system undergoes a...
• Spin-spin couplingThe magnetic interaction between the nuclear spins of different atoms within a molecule, transmitted through...
• Spin-spin coupling constantA parameter that quantifies the interaction between the nuclear spins of different atoms in a molecule...
• Spin-spin relaxationThe loss of magnetization in the plane perpendicular to the static field through energy exchange between...
• Spin-spin relaxation timeThe time constant T2 for the decay of transverse magnetization in nuclear magnetic resonance, caused by...
• Spin-state transitionA change in the total spin angular momentum of a metal ion in a coordination complex, usually induced by...
• Spin-statistical factorA numerical factor that accounts for the probability of forming a particular spin state from a pair of...
• Spiral arterioleA small artery that supplies blood to the functional layer of the endometrium in the uterus. These blood...
• Spiro chainA double-strand polymer chain made of a continuous series of rings in which each pair of neighbouring rings...
• Spiro compoundsOrganic compounds characterized by having at least two rings joined at a single common atom, which is called...
• Spiro macromoleculeA double-strand macromolecule made of a continuous series of rings in which each pair of adjacent rings has...
• Spiro unionThe structural feature in a spiro compound where two rings share only one common atom. This shared atom...
• SpleenA lymphoid organ located in the upper left abdomen, responsible for filtering blood and playing a central...
• SplenicDescribing anything pertaining to or associated with the spleen, a lymphoid organ involved in blood...
• SplenocyteAny mononuclear cell derived from the spleen, including lymphocytes (T cells and B cells) and macrophages...
• SplicingA process in molecular biology where introns, non-coding regions, are removed from a precursor messenger RNA...
• Split adjuvant techniqueA guinea pig assay for the skin-sensitizing potential of a chemical, in which the test substance is applied...
• Split-flow thin-cell fractionationA continuous, semi-preparative separation in a thin laminar-flow channel with two inlets and two outlets...
• SpondylitisAn inflammatory condition affecting the joints of the vertebral column, leading to pain and stiffness. It is...
• SpongioblastA primitive neuroectodermal cell that arises from the epithelial lining of the neural tube during embryonic...
• Spontaneous abortionThe unintended termination of a pregnancy before the fetus has reached a stage of viability, resulting in the...
• Spontaneous autoimmune thyroiditisAn autoimmune disorder characterized by the immune system mistakenly attacking the thyroid gland, leading to...
• Spontaneous emissionThe process by which an excited atom, molecule, or other quantum system decays to a lower energy state by...
• Spontaneous fissionA form of radioactive decay where a heavy atomic nucleus divides into two or more smaller, lighter nuclei...
• Spontaneous terminationA termination reaction in a chain polymerization that is a unimolecular process involving only the active...
• SpotA zone of finite area on a chromatogram, typically circular or elliptical, where a separated component of a...
• Spray chamberA device positioned between a nebulizer and an atomizer in atomic spectrometry systems that converts a liquid...
• Spray ionizationA soft ionization technique used in mass spectrometry where a solution containing the analyte is nebulized...
• SprayerA device that disperses a liquid into a fine mist or aerosol of small droplets. This process is achieved by...
• Spread monolayerA single layer of molecules adsorbed or spread onto a liquid surface, typically water, where the molecules...
• SpreaderA substance added to a liquid formulation, such as a pesticide or herbicide, to enhance its ability to spread...
• Spreading functionA mathematical function that describes the broadening of an initially sharp peak of a monodisperse solute as...
• Spreading wettingA phenomenon where a liquid spreads spontaneously over a solid surface, forming a thin film. This occurs when...
• Sputter depth profileA technique in surface analysis where material is progressively removed from a sample surface by ion...
• Sputter rateThe rate at which atoms or molecules are ejected from a solid surface due to bombardment by energetic...
• Sputter yieldThe average number of atoms or molecules ejected from a solid surface per incident energetic particle...
• SputteringThe ejection of atoms, ions, or molecular fragments from a solid surface as a result of bombardment by...
• Sputtering rateThe quantity of sample material, given as an amount, a mass or a number of particles, that is removed by...
• Sputtering yieldThe ratio of the number of atoms or molecules ejected from a solid surface to the number of incident...
• Square-wave currentA current component in square-wave voltammetry that arises from the presence of a particular substance...
• Square-wave voltammetryA pulse voltammetric technique where a square-wave potential is superimposed on a staircase potential ramp...
• Stability constantAn equilibrium constant that quantifies the strength of the interaction between a metal ion and a ligand to...
• Stability half lifeThe time required for the concentration of a substance to decrease to half of its initial value under...
• Stability ratioA quantitative measure of the stability of a colloidal dispersion against aggregation, particularly in the...
• StableA thermodynamic descriptor of a chemical species, measured by relative standard molar Gibbs energies. Species...
• Stable age distributionA demographic state within a population where the proportion of individuals in each age group remains...
• Stable film, metastable filmA stable film is a thin layer of material that exists in a state of thermodynamic equilibrium, meaning it has...
• Stable ionAn ion that possesses a relatively long lifetime under specific experimental conditions, allowing for its...
• Stable isotope labellingA technique where specific atoms within a molecule are replaced with their non-radioactive, heavier isotopes...
• Stable isotope ratio analysis of amino acids in cell cultureA metabolic labelling approach in which cultured cells grow in medium containing amino acids enriched in...
• Stable isotope standards and capture by anti-peptide antibodiesA quantitative proteomics method that uses synthetic peptides labeled with stable isotopes as internal...
• Stable populationA theoretical population model that maintains a constant age structure and growth rate over time, assuming...
• Stable radicalA free radical species that exhibits a significantly longer lifetime compared to typical transient radicals...
• Stable-radical-mediated polymerizationA type of reversible-deactivation radical polymerization where a stable radical reversibly reacts with a...
• Stably transfected cellsCells that have incorporated foreign genetic material (DNA) into their genome, allowing for its continuous...
• Stacking interactionsNon-covalent attractive forces between aromatic rings that are stacked parallel or nearly parallel to each...
• StageA discrete step or equilibrium section within a multi-step separation process, such as liquid-liquid...
• Stagewise contactorAn apparatus designed to perform a separation process in a series of discrete equilibrium steps, or stages...
• Staggered conformationA spatial arrangement of atoms in a molecule where the substituents on adjacent atoms are as far apart as...
• StampA mold or template used in nanoimprint lithography to transfer a pattern onto a polymer resist film. The...
• StandardA reference material or established criterion used for comparison, measurement, or to define a level of...
• Standard acceleration of free fallThe nominal value of the acceleration due to gravity at the Earth's surface, adopted as a standard for...
• Standard amount concentrationA conventional reference value of amount concentration, written c° and usually set at 1 mol dm-3, used to...
• Standard atmosphereA unit of pressure defined as 101 325 pascals (Pa). This value was historically based on the average...
• Standard atomic weightsThe weighted average of the relative atomic masses of all naturally occurring isotopes of an element...
• Standard chemical potentialThe chemical potential of a substance in its standard state, representing the partial molar Gibbs energy...
• Standard concentrationA reference concentration used to define the standard state for solutes in solution, typically 1 mol/L (or 1...
• Standard conditions for gasesReference values of temperature and pressure used to state gas volumes, set by IUPAC at 273.15 K (0 degrees...
• Standard deviationA measure of the dispersion or spread of a set of data points around their mean value. It quantifies the...
• Standard deviation for proficiency assessmentA measure of dispersion used to evaluate participants' results in a proficiency testing scheme, serving as...
• Standard electrode potentialThe electromotive force of a half-cell reaction measured under standard conditions, relative to a standard...
• Standard electromotive forceThe electromotive force (EMF) of an electrochemical cell when all reactants and products are in their...
• Standard entropy of activationThe change in entropy when reactants transform into the activated complex, with all species in their standard...
• Standard equilibrium constantThe equilibrium constant for a reaction where all reactants and products are in their standard states. It is...
• Standard error of estimatesA measure of the average distance that observed values fall from the regression line in a statistical model...
• Standard error of predictionA statistical measure in computational chemistry that quantifies the accuracy of a model's predictions. It is...
• Standard error of the meanA statistical measure of the variability of sample means around the true population mean. It quantifies how...
• Standard Gibbs energy of activationThe change in Gibbs energy when reactants transform into the activated complex, with all species in their...
• Standard hydrogen electrodeA reference electrode consisting of a platinum electrode immersed in an acidic solution with a hydrogen ion...
• Standard molalityA reference molality used to define the standard state for solutes in solution, typically 1 mol/kg. This...
• Standard morbidity ratioA measure used in epidemiology to compare the observed number of cases of a specific disease in a study...
• Standard mortality ratioThe number of deaths actually observed in a study population divided by the number expected if that...
• Standard operating procedureA set of detailed, written instructions for performing a routine laboratory operation or analytical test. An...
• Standard potential of an electrode reactionThe potential of a half-cell reaction when all species involved are in their standard states. This value...
• Standard potential of the reaction in a chemical cellThe electromotive force of a chemical cell when all reactants and products are in their standard states. This...
• Standard reaction quantitiesThe changes in enthalpy, entropy, Gibbs energy and similar functions that accompany a reaction carried out...
• Standard solutionA solution of precisely known concentration, prepared from a primary or secondary standard, used as a...
• Standard stateA precisely defined reference state for a substance, used to compare thermodynamic properties. For a pure...
• Standard subtraction methodAn electroanalytical calibration approach related to standard addition, in which a known amount of a reagent...
• Standard thermodynamic quantitiesValues of thermodynamic properties, such as enthalpy, entropy, and Gibbs energy, determined under a defined...
• Standard uncertaintyA measure of the uncertainty of a measurement result, expressed as a standard deviation. It quantifies the...
• Standard vacuum levelA conventional reference energy for electron spectroscopy, placed 4.500 eV higher in electric potential than...
• StandardizationThe process of determining the exact concentration of a solution, known as a titrant, by reacting it with a...
• Stand-by stateA condition of an analytical instrument or system where it is powered on and ready for immediate operation...
• StannosisA benign pneumoconiosis resulting from the inhalation and retention of tin or tin oxide dust in the lungs...
• StannoxanesA class of organotin compounds characterized by the presence of a tin-oxygen-tin (Sn-O-Sn) linkage within...
• StannylidenesReactive intermediates with the general formula R2Sn, containing a divalent tin atom bonded to two...
• Star copolymerA star-shaped macromolecule in which arms that differ in constitution or configuration are joined through a...
• Star macromoleculeA macromolecule characterized by multiple linear polymer chains, known as arms, covalently linked to a...
• Star polymerA polymer characterized by a central core from which three or more linear polymer chains, or arms, emanate...
• Stark effectThe alteration of atomic and molecular spectral lines, including their splitting and shifting, when the...
• Starting lineThe initial position on a planar chromatography medium, such as a thin-layer chromatography plate or paper...
• Startle reactionA rapid, involuntary physiological and behavioral response to a sudden, intense sensory stimulus, such as a...
• Startle reflexAn involuntary, rapid, and widespread motor response to an unexpected, intense sensory stimulus, such as a...
• Start-up timeThe time interval between turning an instrument on and its reaching the stand-by state, the condition in...
• State-to-state kineticsA detailed approach to chemical kinetics that considers the specific quantum states of reactants and products...
• Static extractionA one-step batch process in which the extracting solvent reaches a steady composition before the two layers...
• Static fieldA time-invariant electric or magnetic field used in mass spectrometry to separate ions based on their...
• Static fields mass spectrometerA type of mass spectrometer that uses constant electric and magnetic fields to separate ions based on their...
• Static headspace analysisA technique for analyzing volatile compounds in a sample by equilibrating the sample in a sealed vial at a...
• Static light scatteringA technique used to determine the molar mass, size, and shape of macromolecules in solution by measuring the...
• Static magnetic flux densityThe strength of a constant, non-varying magnetic field, typically denoted by B0, which is applied to a sample...
• Static pressureThe pressure a fluid exerts in all directions when at rest, or, for a moving fluid, the pressure that acts...
• Static secondary-ion mass spectrometryA secondary-ion mass spectrometry method that uses a low primary-ion current density so that only the...
• Static self-assemblyA process where pre-existing components spontaneously arrange into ordered structures at equilibrium, driven...
• Static stabilityA measure of the atmosphere's resistance to vertical motion, determined by the temperature lapse rate...
• Static structure factorA measure of the spatial correlations between particles in a system, often determined by scattering...
• Static techniqueAn experimental method in thermal analysis where the sample is held at a constant temperature for a period...
• Static-renewal testA toxicity testing method where test organisms are exposed to a toxicant in a static solution that is...
• Static-toxicity testA toxicity testing method where test organisms are exposed to a toxicant in a fixed volume of solution that...
• Stationary phaseA substance that remains fixed in place within a chromatographic system, providing a surface or medium for...
• Stationary phase volumeThe volume of liquid stationary phase, or of active solid or gel, held in a chromatographic column, symbol...
• Stationary stateA state of a system in which all observable properties are constant over time. In quantum mechanics, a...
• Stationary-phase fractionThe fraction of the total volume inside a chromatography column that is occupied by the stationary phase. It...
• Statistical copolymerA copolymer in which the sequential distribution of the different monomeric units along the polymer chain...
• Statistical copolymerizationA copolymerization process in which the different monomeric units are incorporated into the growing polymer...
• Statistical process controlA method of quality control that employs statistical methods to monitor and manage a process, such as an...
• Statistical segmentA hypothetical segment of a polymer chain that is long enough for its orientation to be statistically...
• Status epilepticusA neurological emergency characterized by continuous seizure activity lasting for an extended period...
• Steady stateA condition in a system where all macroscopic properties, such as concentrations, temperatures, or pressures...
• Steady state extractionAn extraction process where the concentrations of all components in both the feed and extract phases remain...
• Steady-state sputteringA condition achieved during sputtering where the rate of material removal from a surface becomes constant...
• Steady-state surface composition sputteringThe surface composition reached when a homogeneous sample is sputtered under constant conditions, also called...
• StealthA characteristic of a material, often a polymer, that allows it to evade detection or recognition by...
• Stefan-Boltzmann constantA fundamental physical constant that relates the total energy radiated per unit surface area of a black body...
• StemA relatively short, ordered portion of a polymer chain that traverses a crystalline lamella from one fold...
• Stem cellAn undifferentiated cell capable of self-renewal and differentiation into specialized cell types. These cells...
• StenosisThe abnormal narrowing of a bodily passage, duct, or vessel. This constriction can impede the flow of fluids...
• StentA medical device, usually a mesh tube, inserted into a natural passage or conduit in the body to prevent or...
• StepThe portion of an integral chromatogram that records the amount of a component, seen as a rise of the signal...
• Step heightThe vertical distance between two adjacent plateaus on a chromatogram, representing the change in detector...
• Step-scan interferometerAn instrument used in Fourier-transform spectroscopy where the optical path difference is changed in discrete...
• Stepwise elutionA mode of chromatography in which the eluent is switched, one or more times, from one fixed composition to a...
• Stepwise reactionA chemical reaction that proceeds through a series of elementary steps, each involving one or more...
• Stepwise techniqueA method in thermal analysis where a sample is heated or cooled in a series of discrete steps, with...
• SteradianThe SI unit of solid angle, defined as the solid angle subtended at the center of a sphere by a portion of...
• Stereoblock macromoleculeA block macromolecule composed of stereoblocks, which are blocks that have different stereochemical...
• Stereoblock polymerA polymer whose molecules are stereoblock macromolecules, each with at least two blocks of the same...
• Stereochemical formulaA two-dimensional representation of a three-dimensional molecule that depicts the spatial arrangement of its...
• Stereochemical non-rigidityThe property of a molecule or molecular entity that undergoes rapid interconversion between different...
• StereoconvergenceA process in which two or more stereoisomeric starting materials react to yield a single stereoisomeric...
• StereocopolymerA copolymer in which the different monomeric units or sequences within the polymer chain exhibit distinct...
• StereodescriptorA symbol or set of symbols used to specify the absolute or relative configuration of a stereogenic element...
• StereoelectronicRelating to the interplay between the spatial arrangement of atoms (steric factors) and the electronic...
• Stereoelectronic controlThe influence exerted by the spatial arrangement of electron orbitals and groups within a molecule on the...
• Stereogenic centerAn atom in a molecule that is bonded to a set of ligands in such a way that exchanging any two ligands leads...
• Stereogenic unitA grouping of atoms within a molecule that serves as a focus of stereoisomerism, such that interchanging two...
• StereoheterotopicConstitutionally equivalent ligands or faces that cannot be interchanged by a rotation, so that substituting...
• StereohomosequenceA run of constitutional units of one species in a single arrangement, for which the spatial configuration at...
• StereoisomerismThe existence of isomers that have the same constitution, meaning identical connectivity and bond...
• StereoisomersIsomers possessing an identical constitution, meaning the same atoms are connected in the same sequence, but...
• StereologyA body of mathematical methods for estimating three-dimensional properties of objects from two-dimensional...
• StereomutationThe conversion of one stereoisomer into another through an altered configuration at a stereogenic unit...
• Stereoregular macromoleculeA macromolecule in which the stereochemical configuration at each stereogenic center along the polymer chain...
• Stereoregular polymerA regular polymer whose molecules can be described by only one species of configurational repeating unit in a...
• Stereorepeating unitA repeating unit within a polymer chain that possesses a specific stereochemical configuration. This unit is...
• Stereoselective polymerizationA polymerization in which a blend of stereoisomeric monomers yields polymer molecules built from only one of...
• Stereoselective synthesisA chemical reaction or sequence of reactions that produces a predominant amount of one stereoisomer over...
• StereoselectivityThe preferential formation of one stereoisomer over another in a chemical reaction, resulting in an unequal...
• StereosequenceA stretch of a polymer's main chain in which the configuration, relative or absolute, is stated at every site...
• Stereospecific polymerizationA polymerization process that leads to the formation of a polymer with a defined stereochemical configuration...

1,437 of 13,676 terms in Chemistry terminology (MLC-0109). Request the full dataset.