Chemistry terminology · MLC-0109
Chemistry terms: S (1,437)
- σ, πSymbols representing types of covalent bonds formed by the overlap of atomic orbitals. A sigma (σ) bond...
- S9 fractionA supernatant fraction obtained from the centrifugation of homogenized liver tissue, typically at 9000 x g...
- Saccadic eye movementRapid, ballistic jumps of the eyes that move the fovea from one fixation point to another, as in reading or...
- SaccharidesCarbohydrates in the broad sense, covering monosaccharides, disaccharides, oligosaccharides and...
- SaccharolipidsA class of lipids in which fatty acids are linked directly to a sugar backbone, forming structures that are...
- Sackur-Tetrode constantA dimensionless constant equal to the molar entropy of an ideal monatomic gas of atoms with relative atomic...
- Sacral agenesisA congenital malformation characterized by the partial or complete absence of the sacrum, the triangular bone...
- Sacrificial acceptorA molecular entity that takes up the electron in a photoinduced electron transfer and is then destroyed by an...
- Sacrificial donorA molecular entity that supplies the electron in a photoinduced electron transfer and is then destroyed by an...
- Saddle field gunAn ion source that generates a beam of ions or neutral atoms by creating a plasma within a saddle-shaped...
- Σ-adductA species formed by the addition of an electrophile or nucleophile to a carbon atom of an aromatic or...
- Safe concentrationA concentration of a substance in the environment that is not expected to cause adverse effects on organisms...
- SafetyThe practical certainty that exposure to a substance under stated conditions of use will not cause injury or...
- Safety data sheetA document providing information about the properties of a chemical substance or mixture, its potential...
- Safety pharmacologyA branch of pharmacology that investigates the potential undesirable pharmacodynamic effects of a substance...
- SagittalDescribing an anatomical plane that divides a body or organ into left and right portions. This division can...
- Saha’s ionization equationA mathematical formula that describes the degree of ionization of a gas in thermal equilibrium as a function...
- Saint Anthony fireA historical name for the disease ergotism, caused by ingesting alkaloids produced by the fungus Claviceps...
- SalinityThe total concentration of all dissolved salts in water, primarily sodium chloride, but also including...
- SalivaThe fluid secreted into the oral cavity by the salivary glands, which serves to lubricate food, initiate...
- SalpingectomyA surgical procedure for the excision of one (unilateral) or both (bilateral) of the Fallopian tubes. This...
- SaltAn ionic compound formed from the reaction of an acid and a base, consisting of a cation from a base and an...
- Salt bridgeA device used in electrochemical cells to connect two half-cells, allowing the flow of ions to maintain...
- Salt form of an ion exchangerAn ion exchanger where the counter-ions are not hydrogen ions or hydroxide ions. This form is typically...
- Salt tolerance indexA quantitative measure of an organism's ability to withstand and grow in environments with elevated salt...
- Salting inThe phenomenon where the solubility of a sparingly soluble substance in a solvent is increased by the...
- Salting outThe reduction in the solubility of a substance, particularly a protein or other macromolecule, in an aqueous...
- SampleA part taken from a larger amount of material so that its properties or composition can be used to draw...
- Sample biasAn electric potential applied to the whole sample or to part of it, measured against the potential of the...
- Sample chargingThe accumulation of electrostatic charge on the surface of a non-conductive or poorly conductive sample...
- Sample controlled techniqueA method in thermal analysis where the experimental conditions, such as heating rate or atmosphere, are...
- Sample errorAn error in absorbance measurement that arises when the absorbance of a sample changes with time, for example...
- Sample flux densityThe intensity of radiation that emerges from the atomizer while it is fed with a sample solution or, for...
- Sample handlingThe sequence of operations to which a sample is subjected between the sampling process and the final...
- Sample injectorA device used to introduce a discrete, defined volume of a sample into the flowing mobile phase of a...
- Sample pre-treatmentAny process applied to a sample before its analysis to make it suitable for the analytical method or to...
- Sample quality controlA set of procedures implemented to monitor and maintain the integrity and suitability of a biological sample...
- Sample unitA discrete portion of a material that is taken for analysis, representing a larger batch or population. This...
- Sample voltageThe electrical potential applied to a sample during certain surface analysis techniques, such as secondary...
- Sampled DC polarographyA variant of direct current (DC) polarography where the current is measured only for a brief period at the...
- SamplerA device or mechanism used to collect a representative portion of a material for analysis. It can range from...
- SamplingThe process of selecting and taking a portion of a material that is representative of the whole, intended for...
- Sampling coneA small-orifice cone at the front of an atmospheric pressure spray ionization interface, which lets part of...
- Sampling errorThe random or systematic deviation of a sample's characteristics from those of the population from which it...
- Sampling incrementA portion of material collected at one time or from one location during the sampling process. Multiple...
- Sampling intervalThe window of time in each drop life or pulse cycle during which the current is read out in Tast, square-wave...
- Sampling planA procedure fixed in advance for choosing, taking, preserving, transporting and preparing the portions that...
- Sampling targetThe specific material, object, or system from which a sample is intended to be collected for analysis. This...
- Sampling timeThe duration during which a sample is actively being collected or measured in an analytical procedure. This...
- Sampling unitA discrete portion of a material or population that is selected for analysis. This unit can be a single item...
- Sandwich compoundsOrganometallic compounds where a metal atom is 'sandwiched' between two planar organic ligands, typically...
- Sandwich immunoassayA type of immunoassay where the analyte is bound between two antibodies, forming a 'sandwich' complex. One...
- Sanger sequencingA method for determining the nucleotide sequence of DNA, based on the selective incorporation of...
- Sanitary land fillA method of solid waste disposal where refuse is buried in layers, compacted, and covered with soil or other...
- Santa Ana dexterity testA standardized test of manual dexterity in which the subject stands before a board with 48 square holes, each...
- SaprobicRelating to an organism that derives its nourishment from nonliving or decaying organic matter. Saprobic...
- Saprobic indexA numerical value used to assess the level of organic pollution in aquatic ecosystems based on the presence...
- Saprobic water classificationA system for categorizing the quality of freshwaters based on the biological communities present...
- Saprobien spectrumA classification system used to assess the level of organic pollution in aquatic environments based on the...
- SaprophyteAn organism, particularly a fungus or bacterium, that derives its nourishment from nonliving or decaying...
- SarcoidosisA systemic inflammatory disease characterized by the formation of granulomas, which are small collections of...
- SarcomaA type of malignant tumor that arises from transformed cells of mesenchymal origin, meaning they originate...
- Satellite groupsSmall, additional groups of animals included in a toxicity study alongside the main control and treatment...
- Saturable eliminationA pharmacokinetic process where the rate of elimination of a substance from the body becomes constant once a...
- Saturated solutionA solution that contains the maximum amount of solute that can be dissolved in a given amount of solvent at a...
- Saturating soluteA component in a solution that is present at its maximum solubility limit, meaning the solution is saturated...
- SaturationThe state of a solution that holds the same concentration of a solute as a solution in equilibrium with...
- Saturation activityThe maximum radioactivity that can be induced in a sample when it is irradiated for an infinitely long time...
- Saturation fractionThe proportion of binding sites on a protein or other molecule that are occupied by a specific ligand. This...
- Saturation mutagenesisA molecular biology technique used to create a library of mutant proteins by systematically introducing all...
- Saturation transferA nuclear magnetic resonance (NMR) technique used to detect chemical exchange processes between different...
- Saturation transfer difference spectroscopyA nuclear magnetic resonance (NMR) spectroscopy technique used to detect weak interactions between a ligand...
- Saturation vapour pressureThe maximum pressure that water vapor can exert at a given temperature when it is in thermodynamic...
- SaturatorA buffer solution carrying the interfering element or elements in an amount large enough that the effect on...
- SaturnismA condition caused by lead poisoning, classically the chronic form from repeated exposure, with neurological...
- Sawhorse projectionA method for representing the three-dimensional structure of molecules, particularly alkanes, on a...
- Saytzeff ruleA rule in organic chemistry that predicts the major product of an elimination reaction, specifically...
- Scaffold hoppingA strategy in medicinal chemistry that involves replacing the core scaffold of a known active compound with a...
- ScalerAn electronic circuit designed to count electrical pulses, particularly those generated by radiation...
- ScalingThe process of transforming data to a common range or distribution, often to prevent variables with larger...
- Scaling circuitAn electronic circuit designed to reduce the number of pulses by a fixed integer factor. It produces one...
- Scaling equationA dimensionless relation that collapses the mutual solubility curves of many chemically similar liquid pairs...
- Scaling factorA numerical multiplier used to adjust the magnitude of a quantity or a set of data. In theoretical chemistry...
- Scaling lawA mathematical relationship that describes how a physical quantity changes with respect to another quantity...
- ScanTo systematically vary an experimental parameter over a defined range while measuring a corresponding...
- Scan cycle timeThe total duration required for a mass spectrometer to acquire a complete mass spectrum over a defined...
- Scan rateThe speed at which an instrumental parameter, such as potential in electrochemistry or wavelength in...
- Scanning calorimetryA thermal analysis technique that measures the heat flow into or out of a sample as its temperature is...
- Scanning electron microscopyAn electron microscopy technique that creates images of a sample's surface by scanning it with a high-energy...
- Scanning methodA technique that involves systematically moving a probe or detector across a sample or through a range of...
- Scanning near-field optical microscopyA super-resolution optical imaging technique that overcomes the diffraction limit of conventional microscopy...
- Scanning proton microscopyA microanalytical technique that uses a finely focused beam of high-energy protons to probe the elemental...
- Scanning techniqueA general experimental approach where a physical quantity or spatial position is systematically varied to...
- Scanning transmission electron microscopyAn electron microscopy technique where a finely focused electron beam is scanned across a thin sample...
- Scanning-probe lithographyA nanofabrication technique that uses a sharp probe tip, similar to those in atomic force microscopy, to...
- ScaphocephalyA congenital malformation of the skull characterized by premature fusion of the sagittal suture, resulting in...
- Scatchard equationAn equation for ligand binding to a macromolecule that has a set of independent, identical sites, written r/c...
- Scatchard plotA graphical representation of binding data, derived from the Scatchard equation, where the ratio of bound...
- Scattered-ion energyThe kinetic energy of an ion after it has undergone an elastic collision with an atom on a sample surface...
- Scattered-ion energy ratioThe ratio of the kinetic energy of a scattered ion to the kinetic energy of the incident primary ion. This...
- ScatteringThe process by which particles or radiation deviate from their original trajectory after interacting with...
- Scattering albedoThe ratio of the scattering coefficient to the total extinction coefficient for a medium. It represents the...
- Scattering angleThe angle between the direction of propagation of incident radiation and the direction of propagation of the...
- Scattering coefficientA measure of the probability that radiation will be scattered per unit path length in a medium. It quantifies...
- Scattering cross-sectionA measure of the probability that an incident particle or photon will be scattered by a target particle or...
- Scattering errorAn error in spectrophotometric absorbance measurements in which particles, emulsions or micelles in the...
- Scattering geometryThe spatial arrangement of a radiation source, a sample, and a detector in a scattering experiment. This...
- Scattering matrixA mathematical construct that describes how incident electromagnetic radiation is transformed upon...
- Scattering planeThe geometric plane defined by the direction of an incident beam of radiation or particles and the direction...
- Scattering vectorA vector representing the change in the wavevector between incident and scattered radiation in a scattering...
- ScavengerA chemical species added to a reaction mixture to remove or deactivate highly reactive intermediates, such as...
- Scavenger receptorA cell surface receptor, found chiefly on macrophages, dendritic cells and some endothelial cells, that...
- ScavengingThe process of removing undesirable substances from a system by chemical or physical means, often involving...
- scFvA single-chain variable fragment, which is an engineered antibody fragment consisting of the variable regions...
- Schedule of reinforcementA rule that determines when and how often a reinforcer is delivered in response to a specific behavior. This...
- Schedule-controlled operant behaviourBehavior that is maintained and regulated by a specific schedule of reinforcement, where the pattern and rate...
- Scheduling softwareA computer program used in high-throughput screening to control and coordinate the actions of automated...
- Schenck reactionA photochemical reaction involving the addition of singlet oxygen to an alkene containing an allylic...
- Schenck-sensitization mechanismA photosensitization pathway in which the excited sensitizer forms a temporary covalent bond to the molecule...
- Schiff basesA class of organic compounds containing a carbon-nitrogen double bond, where the nitrogen atom is connected...
- Schiller layersIridescent, ordered layers that form in certain colloidal suspensions containing anisometric particles, such...
- Schottky barrierA potential energy barrier for charge carriers formed at the interface between a metal and a semiconducting...
- Schulze-Hardy ruleA principle stating that the coagulating power of an electrolyte on a colloidal dispersion increases sharply...
- Schulz-Zimm distributionA mathematical function describing the distribution of molecular weights in a polymer sample, particularly...
- Schwann cellA type of glial cell found in the peripheral nervous system that forms the myelin sheath around axons. These...
- ScintillationThe emission of light by a material when it absorbs ionizing radiation. This phenomenon occurs as excited...
- Scintillation counterAn instrument that detects and measures ionizing radiation by converting the energy of the radiation into...
- Scintillation detectorA device that measures ionizing radiation by converting the energy of incident radiation into light pulses...
- Scintillation proximity assayA homogeneous immunoassay technique that measures molecular interactions in solution without the need for...
- Scintillation spectrometerAn instrument that measures the energy distribution of incident radiation by detecting the light flashes, or...
- ScintillatorsMaterials that emit light when excited by ionizing radiation, such as alpha particles, beta particles, or...
- s-cis, s-transConformational isomers that arise from rotation around a single bond connecting two sp2-hybridized atoms...
- SclerodermaA chronic autoimmune disease characterized by the hardening and tightening of the skin and connective...
- SclerosisA pathological hardening of tissue or an organ, typically due to an increase in fibrous connective tissue...
- ScoliosisA medical condition characterized by an abnormal lateral curvature of the spinal column, often accompanied by...
- Scombroid poisoningA type of food poisoning caused by the consumption of certain fish, such as tuna, mackerel, and mahi-mahi...
- Σ-constantA quantitative measure in physical organic chemistry that describes the electronic effect of a substituent on...
- Scope for growthThe difference between the energy assimilated by an organism from its food and the energy expended for its...
- Scope of activityThe difference between an organism's rate of oxygen consumption at maximal activity and its rate at minimal...
- ScoreA new variable created in multivariate data analysis, such as principal component analysis, that represents a...
- Scores plotA graphical representation in multivariate data analysis, particularly principal component analysis, that...
- ScoringA computational method used to estimate the binding affinity between a ligand and a receptor, typically in...
- ScotomaAn area of partial or complete vision loss within an otherwise normal visual field, often described as a...
- ScreenA systematic process of testing a large number of chemical compounds or biological samples for a specific...
- Screen validationThe process of confirming that a high-throughput screening assay is reliable, reproducible, and suitable for...
- ScreeningThe reduction of the effective charge of an atomic nucleus experienced by an electron due to the presence of...
- Screening functionA correction factor applied to the Rutherford scattering cross section for an ion colliding with a target...
- Screening levelA concentration or dose of a substance below which adverse effects are not expected to occur in a given...
- Screening testA preliminary assessment designed to detect the presence or absence of a particular effect or substance in a...
- ScrotumA pouch of skin and smooth muscle that contains the testes in most male mammals. Its primary function is to...
- ScrubberAn air pollution control device that removes particulate matter and/or gases from industrial exhaust streams...
- ScrubbingA process used to remove gaseous pollutants or undesirable components from a gas stream by passing it through...
- Sechenov equationAn empirical equation that describes the salting-out effect, which is the decrease in the solubility of a...
- Seco-A prefix used in chemical nomenclature to denote a compound formed by the cleavage of a ring in a parent...
- Second harmonic generationA nonlinear optical phenomenon where two photons of identical frequency interact with a material, resulting...
- Second messengerAn intracellular signaling molecule that relays signals from receptors on the cell surface to target...
- Second set rejectionA phenomenon observed in transplantation immunology where a second graft from the same donor, or a donor...
- Secondary challengeThe re-exposure of an organism to an antigen after an initial priming exposure, leading to a more rapid and...
- Secondary crystallizationThe process of further ordering and perfection of crystalline regions in a polymer after the initial primary...
- Secondary electron multiplierA detector used in mass spectrometry and other instruments to amplify a small ion current into a measurable...
- Secondary electronsElectrons emitted from a material surface as a result of inelastic scattering events with incident primary...
- Secondary examination standardA substance or material whose property value is assigned through comparison with a primary examination...
- Secondary fluorescenceThe emission of characteristic X-rays by an atom that has been excited by absorbing X-rays from a...
- Secondary immune responseThe immune reaction that occurs upon re-exposure to an antigen previously encountered, characterized by a...
- Secondary ionAn ion that is ejected from the surface of a solid material as a result of bombardment by a primary ion beam...
- Secondary ionizationThe emission of ions from the surface of a solid or liquid sample when it is struck by a beam of energetic...
- Secondary isotope effectAn isotope effect observed when isotopic substitution occurs at a position in a molecule that is not directly...
- Secondary lamellaeThin, plate-like structures that project from the primary lamellae of fish gills, forming the primary sites...
- Secondary lymphoid tissueOrganized tissues where mature, naive lymphocytes encounter antigens, become activated, and differentiate...
- Secondary metabolitesOrganic compounds produced by an organism that are not directly involved in its fundamental processes of...
- Secondary neutral mass spectrometryA mass spectrometry technique that analyzes neutral species sputtered or desorbed from a surface, which are...
- Secondary nucleationThe formation of new crystal nuclei on the surface of existing crystals during the crystallization of a...
- Secondary oocyteA haploid female gamete that results from the completion of meiosis I in the primary oocyte, containing most...
- Secondary parkinsonismA condition characterized by symptoms resembling Parkinson's disease, such as tremor, rigidity, bradykinesia...
- Secondary poisoningThe adverse effect on an organism resulting from the consumption of another organism that has accumulated a...
- Secondary pollutionAir pollutants that are not directly emitted from a source but form in the atmosphere through chemical...
- Secondary radiationRadiation emitted by an irradiated material as a result of the interaction of primary radiation with the...
- Secondary radicalA free radical in which the unpaired electron is located on a carbon atom that is bonded to two other carbon...
- Secondary relaxationA molecular motion in polymers that occurs at temperatures below the glass transition temperature, involving...
- Secondary relaxation peakA peak observed in the mechanical or dielectric loss spectrum of a polymer at temperatures below the glass...
- Secondary relaxation temperatureA characteristic temperature below the glass transition temperature at which localized molecular motions...
- Secondary screenA set of assays performed on compounds identified as 'hits' from a primary high-throughput screening...
- Secondary sexual characteristicA physical or behavioral trait that appears during puberty, distinguishing between the sexes of a species...
- Secondary speciesA species formed when a primary species, such as an initiator-derived radical, rearranges or fragments into...
- Secondary structureThe local spatial arrangement of the polypeptide backbone in a protein, stabilized by hydrogen bonds between...
- Secondary substrate metabolismThe metabolic transformation of a chemical compound by microorganisms that do not derive energy or carbon...
- Secondary successionThe ecological process of community change and development that occurs in an area where an existing community...
- Secondary-electron yieldThe ratio of the number of secondary electrons emitted from a surface to the number of primary electrons...
- Secondary-ion angular distributionThe spatial distribution of secondary ions ejected from a surface during sputtering, describing the angles at...
- Secondary-ion energy distributionThe distribution of kinetic energies of secondary ions ejected from a surface during sputtering by primary...
- Secondary-ion mass spectrometryA surface-sensitive analytical technique that uses a focused primary ion beam to sputter material from a...
- Secondary-ion yieldThe number of secondary ions produced per incident primary ion during the sputtering process in techniques...
- Second-order transitionA phase transition where the first derivatives of the Gibbs free energy with respect to temperature and...
- SecretionThe process by which cells or glands produce and release substances, such as hormones, enzymes, or mucus...
- Secretory componentA protein fragment derived from the polymeric immunoglobulin receptor that becomes attached to dimeric...
- Secretory immunoglobulin AA dimeric form of immunoglobulin A (IgA) that is found in external secretions such as tears, saliva, mucus...
- Sector mass spectrometerA type of mass spectrometer that separates ions based on their mass-to-charge ratio using a combination of...
- Secular equationA mathematical equation that arises in quantum mechanics, particularly in the context of molecular orbital...
- Secular equilibriumA state of radioactive equilibrium where a long-lived parent radionuclide decays to a shorter-lived daughter...
- SedimentThe material that settles to the bottom of a liquid from a suspension under the influence of gravity or a...
- SedimentationThe process by which particles suspended in a fluid settle out due to the force of gravity or centrifugal...
- Sedimentation coefficientThe ratio of the constant sedimentation velocity of a particle to the applied acceleration field causing the...
- Sedimentation equilibriumA state achieved in an ultracentrifuge where the rate of sedimentation of macromolecules is balanced by their...
- Sedimentation field strengthThe electric field strength produced along a column of suspension in which charged particles are settling...
- Sedimentation field-flow fractionationA field-flow fractionation technique that uses a centrifugal force field applied perpendicular to the flow of...
- Sedimentation potential differenceAn electric potential that develops across a suspension of charged particles when they settle under the...
- Sedimentation velocityThe rate at which particles or molecules move through a fluid under the influence of a centrifugal force...
- Sedimentation velocity methodA technique used to determine the molar mass and hydrodynamic properties of macromolecules by observing their...
- Sedimentation volumeThe final volume occupied by a sedimented solid phase after a suspension has settled under gravity or...
- Seed particleA pre-formed polymer particle introduced into a polymerization system to serve as a template for further...
- Seeded dispersion polymerisationA polymerization technique where pre-existing polymer seed particles are used to initiate and control the...
- Seeded emulsion polymerisationA variant of emulsion polymerization where a small amount of pre-formed polymer latex (seed) is added to the...
- SegmentA defined, discrete portion of a material being sampled, or a discrete volume of liquid within a flowing...
- Segmented copolymerA copolymer composed of relatively long sequences (segments) of two or more different types of monomer units...
- Segmented flow analysisA method of continuous flow analysis where the sample stream is divided into discrete segments by the...
- Segmented flow extractionA liquid-liquid extraction technique performed within a segmented flow system, where an aqueous sample and an...
- SegregationThe non-uniform distribution of the components of a solid solution, resulting in concentration differences...
- SeizureA transient occurrence of signs or symptoms resulting from abnormal, excessive, or synchronous neuronal...
- Selected ion flow tubeAn analytical instrument used in mass spectrometry to study gas-phase ion-molecule reactions at thermal...
- Selected ion monitoringA mass spectrometry technique where the detector is set to monitor only a few specific ion m/z...
- Selected reaction monitoringA tandem mass spectrometry technique where a specific precursor ion is selected in the first mass analyzer...
- Selected-area apertureA physical opening, typically circular, placed in the optical path of an electron microscope to define the...
- SelectinA family of cell adhesion molecules that mediate the initial rolling interactions of leukocytes on...
- SelectionThe process of isolating or favoring specific cells, organisms, or genetic traits from a heterogeneous...
- Selection componentsThe distinct stages or processes within an organism's life cycle where natural selection acts, influencing...
- Selection ruleA rule, derived from the symmetry and spin of the initial and final wavefunctions, that states whether a...
- SelectiveDescribing an analytical method or reagent that responds preferentially to a particular analyte or group of...
- Selective corrosionA form of corrosion where one component of an alloy or composite material is preferentially attacked and...
- Selective decouplingA nuclear magnetic resonance technique in which one specific resonance is irradiated with a radiofrequency...
- Selective elutionThe process in chromatography where a specific component or group of components is preferentially removed...
- Selective excitationThe process of exciting only a specific subset of nuclei or energy levels within a sample, typically using...
- Selective IgA deficiencyA primary immunodeficiency characterized by significantly reduced levels of immunoglobulin A (IgA) in serum...
- Selective micro-sampleA very small portion of a larger sample that has been deliberately chosen for analysis based on specific...
- Selective poisoningThe process by which a catalyst's activity is reduced or eliminated for specific reactions or reactants...
- Selective preconcentrationA process that increases the concentration of a specific analyte or group of analytes from a larger volume of...
- Selective pulseA radiofrequency pulse in nuclear magnetic resonance (NMR) spectroscopy designed to excite only a narrow...
- Selective sampleA sample chosen deliberately from a larger population based on specific criteria or characteristics, rather...
- Selective serotonin reuptake inhibitorA class of antidepressant drugs that primarily increase the extracellular level of the neurotransmitter...
- Selective solventA solvent that preferentially dissolves one block or segment of a block copolymer while acting as a...
- Selectively labelledDescribing a chemical compound in which one or more specific atoms of a particular element are replaced by...
- Selectively-labelled isotopic tracerA molecule in which one or more specific atoms have been replaced by their stable or radioactive isotopes at...
- SelectivityThe preference of a reagent to react with one specific site or substrate over others, or the preference of a...
- Selectivity assayA biochemical or cellular assay designed to evaluate the ability of a compound to preferentially interact...
- Selectivity coefficientAn equilibrium coefficient from the mass action law for ion exchange that quantifies how strongly an ion...
- Selectivity factorA measure of how strongly a monosubstituted benzene discriminates between the para and meta positions in a...
- Selectivity ratioAnother name for the selectivity coefficient of an ion exchanger, the equilibrium quantity from the law of...
- Selector geneA gene that controls the developmental fate of a group of cells or an entire body segment by regulating the...
- Selenenic acidsOrganic compounds containing the -SeOH functional group, where selenium is directly bonded to an organic...
- SelenidesOrganic compounds containing a selenium atom bonded to two organic groups, with the general formula R-Se-R'...
- Seleninic acidsOrganoselenium acids of the formula RSe(O)OH, in which selenium carries an organic group, a double-bonded...
- SelenocyanatesOrganic compounds containing the -SeCN functional group, where a selenium atom is bonded to an organic group...
- SelenolsOrganoselenium compounds with the general structure R-SeH, where a selenohydryl group is bonded to a carbon...
- SelenonesOrganoselenium compounds with the general formula R-Se(=O)2-R', where two organic groups are attached to a...
- Selenonic acidsOrganic compounds containing the -SeO3H functional group, where selenium is in its highest oxidation state...
- SelenoxidesOrganoselenium compounds with the general formula R-Se(=O)-R', where a selenium atom is bonded to two organic...
- Self inductanceThe property of an electrical conductor, such as a coil, to oppose changes in the electric current flowing...
- Self-absorptionThe re-absorption of emitted radiation by the same substance that produced it, occurring when the emitted...
- Self-absorption broadeningThe phenomenon in atomic emission spectroscopy where emitted radiation from excited atoms is reabsorbed by...
- Self-absorption effectThe reduction in the observed intensity of emitted radiation due to reabsorption by unexcited species of the...
- Self-absorption factorA correction factor applied in radioanalytical chemistry to account for the attenuation of radiation within...
- Self-assembled monolayerA molecular assembly that spontaneously forms an ordered, single-molecular layer on a solid surface through...
- Self-assemblyThe spontaneous and reversible organization of disordered components, such as molecules or macromolecules...
- Self-avoiding random-walk chainA theoretical model for a polymer chain where the chain segments are not allowed to occupy the same spatial...
- Self-chemical ionizationA chemical ionization process in mass spectrometry where the sample molecules themselves act as both the...
- Self-cleaning of waterThe natural process by which bodies of water, such as rivers and lakes, remove pollutants and restore their...
- Self-diffusion coefficientA coefficient describing how fast molecules of a substance wander through the pure substance, or through a...
- Self-initiated polymerisationA polymerization process that proceeds without the addition of an external initiator, where the monomer...
- Self-localized excitationsElectronic excitations that become trapped or localized in a specific region of a material due to...
- Self-nucleationA process in polymer crystallization where residual crystalline fragments or highly ordered regions, formed...
- Self-poisoningThe deactivation of a catalyst by one of the products of the reaction it catalyzes, or by a reactant that...
- Self-purification of the atmosphereThe natural processes by which the Earth's atmosphere removes pollutants and maintains its chemical...
- Self-quenchingThe reduction in the fluorescence or phosphorescence quantum yield of a substance due to interactions between...
- Self-reversalA phenomenon in atomic emission spectroscopy where the intensity of a spectral line decreases at its center...
- Self-shieldingThe reduction in the effective neutron flux within a sample due to the absorption of neutrons by the sample...
- Self-toleranceThe state of immunological unresponsiveness to an individual's own antigens, preventing the immune system...
- Sella turcicaA depression in the superior surface of the sphenoid bone, located at the base of the human skull. This...
- SelonesOrganic compounds containing a carbon-selenium double bond, analogous to ketones where the oxygen atom is...
- Selyean stressThe physiological and psychological response of an organism to any demand placed upon it, as described by...
- Semelparous speciesA species characterized by a single reproductive episode during its entire lifespan, after which it typically...
- SemenThe fluid ejaculated by male animals, containing spermatozoa and secretions from accessory glands such as the...
- SemicarbazonesOrganic compounds formed by the condensation reaction of an aldehyde or ketone with semicarbazide...
- SemicokeA solid carbonaceous residue obtained from the low-temperature carbonization of coal or other carbon-rich...
- Semiconductor detectorA radiation detector that uses a semiconductor material to convert incident radiation into an electrical...
- Semiconductor-metal transitionA phase transition in which a material changes from a semiconducting state, characterized by a finite band...
- Semi-continuous activated sludge testA fill-and-draw laboratory test for the inherent biodegradability of an organic chemical, in which activated...
- Semi-continuous emulsion polymerisationAn emulsion polymerization process where one or more components, typically the monomer, are fed continuously...
- Semi-dendritic constitutional repeating unitA constitutional repeating unit within a polymer structure that possesses a branching point from which at...
- Semi-dilute solutionA polymer solution with a concentration above the overlap concentration, where the coils of neighbouring...
- Semi-empirical quantum mechanical methodsComputational chemistry techniques that simplify ab initio quantum mechanical calculations by incorporating...
- Semi-interpenetrating polymer networkA polymer blend composed of at least two polymers, where one polymer forms a network and the other is a...
- Seminal vesicleA pair of glands in male mammals that secrete a fluid component of semen. This fluid is rich in fructose...
- Seminiferous tubuleHighly convoluted tubules located within the testes, where spermatogenesis, the process of sperm production...
- SemiochemicalA chemical substance or mixture that carries a message between organisms, mediating interactions within or...
- SemioxamazonesCompounds of the type R2C=N-NH-CO-CO-NH2, formally made by condensing an aldehyde or ketone with the...
- Semipermeable membraneA thin layer of material that acts as a selective barrier, permitting the passage of certain molecules or...
- Semipermeable membrane deviceA passive sampling device in which a semipermeable membrane, typically a lay-flat low-density polyethylene...
- SemiquinonesRadical anions formed by the one-electron reduction of a quinone or, alternatively, by the one-electron...
- Semi-rigid chainA polymer chain that exhibits a degree of stiffness or persistence length significantly greater than that of...
- Semisystematic nameA chemical name that combines elements of systematic nomenclature with trivial or common names, often...
- Senile dementiaA progressive and irreversible decline in cognitive function, including memory, language, and problem-solving...
- SenilityA historical and somewhat outdated term referring to the physical and mental deterioration associated with...
- Senior constitutional repeating unitThe constitutional repeating unit chosen from two or more alternatives according to a hierarchical set of...
- SeniorityA principle in chemical nomenclature that establishes a hierarchical order among functional groups or parent...
- Sensitive areaThe specific portion of a radiation detector that responds to incident radiation and contributes to the...
- Sensitive volumeThe specific region within a radiation detector where energy deposition from incident radiation is...
- SensitivityThe slope of an analytical calibration curve, that is the change in instrument signal produced by a unit...
- Sensitivity analysisA method used to determine how the output of a model or system changes in response to variations in its input...
- Sensitivity of a measuring systemThe change in the output signal of a measuring system per unit change in the input quantity being measured...
- SensitizationThe process by which a substance, called a sensitizer, absorbs energy and then transfers that energy to...
- Sensitized luminescenceA process where energy absorbed by one species, the sensitizer, is transferred to another species, the...
- Sensitized strainA model organism strain that carries a mutation in a metabolic or signaling pathway which causes no visible...
- SensorA device that detects and responds to a physical stimulus, such as light, heat, pressure, or a chemical...
- Sensory effect levelA measure of the human sensory response to an airborne substance, expressed through three thresholds. The...
- Sensory neuronA nerve cell that transmits sensory information from peripheral receptors to the central nervous system...
- Sentinel speciesAn organism that provides an early warning of environmental contamination or health hazards due to its...
- Separability assumptionA simplifying assumption in chemical kinetics and quantum mechanics where different modes of motion or...
- Separated flameA premixed flame whose observed region is shielded from room air mechanically, by a tube fitted around the...
- Separation factorA quantitative measure of the effectiveness of a separation process in distinguishing between two components...
- Separation numberA measure of the separation efficiency of a chromatographic column, representing the number of peaks that can...
- Separation temperatureThe temperature held by the chromatographic bed when a separation is run isothermally, called the column...
- SepsisA life-threatening organ dysfunction resulting from a dysregulated host response to an infection. The body's...
- SeptumA dividing wall or partition that separates two cavities or masses of soft tissue within an organism. In...
- SequenceThe specific order of monomeric units within a polymer chain, such as amino acids in a protein or nucleotides...
- SequencingThe determination of the precise order of nucleotides in a deoxyribonucleic acid (DNA) or ribonucleic acid...
- Sequential analyserAn analytical instrument that performs a series of measurements or tests on a single sample, one after...
- Sequential detectionA method of detecting multiple analytes or spectral features by measuring them one after another, rather than...
- Sequential extractionA multi-step procedure that uses a series of reagents to selectively dissolve and separate different chemical...
- Sequential indicationA method of chemical analysis where the instrument provides a series of discrete readings over time rather...
- Sequential injection analysis extraction deviceA microfluidic or mesofluidic system designed for automated liquid-liquid or solid-liquid extraction within a...
- Sequential interpenetrating polymer networkA polymer blend composed of two or more networks, at least one of which is synthesized and/or crosslinked in...
- Sequential measuring cellA component in an analytical instrument designed to hold a series of discrete samples for measurement one...
- Sequential sampleA set of units or increments drawn singly, or in successive small groups, with the measurements assessed...
- Sequential semi-interpenetrating polymer networkA semi-interpenetrating polymer network made in two stages, where the linear or branched polymer is formed...
- Sequential spectrometerAn instrument that measures the intensity of radiation at a series of different wavelengths or frequencies...
- SeriesA number of measured values that are equivalent to each other for statistical purposes, for example the...
- SeroconversionThe development of detectable antibodies in the blood serum in response to an infection or vaccination. This...
- SerologyThe scientific study of blood serum, particularly focusing on the immune system's response to pathogens and...
- SerotoninergicRelating to neurons, synapses, or physiological processes that produce, release, or are activated by the...
- SerousDescribing a fluid or membrane that is thin, watery, and typically pale yellow, resembling blood serum...
- Sertoli cellA type of somatic cell located within the seminiferous tubules of the testis that provides structural and...
- Sertoli-Leydig cell tumorA rare type of ovarian or testicular tumor that originates from sex cord-stromal cells, exhibiting features...
- SerumThe clear, yellowish fluid portion of blood that remains after blood coagulation and the removal of cellular...
- Serum sicknessA type III hypersensitivity reaction that occurs in response to the administration of foreign proteins, such...
- SesquiterpenoidsTerpenoids with a 15-carbon skeleton built from three isoprene units, formed biosynthetically from farnesyl...
- SesterterpenoidsA class of terpenoids containing 25 carbon atoms, derived biosynthetically from five isoprene units. Their...
- SestonAll particulate matter suspended in a body of water, including both living and non-living components. The...
- Settling chamberA device used in air pollution control to remove large particulate matter from gas streams by reducing the...
- Settling errorAn error in spectrophotometric measurement caused by not allowing enough time for the instrument reading to...
- Settling velocityThe constant rate at which a particle falls through a fluid under the influence of gravity when the drag...
- Severe combined immunodeficiencyA group of rare, inherited disorders characterized by a profound defect in both T lymphocyte and B lymphocyte...
- Sex chromatinA condensed, inactive X chromosome observed in the somatic cells of female mammals, also known as a Barr...
- Sex chromosomeA chromosome that determines the sex of an individual, distinguishing it from an autosome. In humans, these...
- Sex-determining region Y proteinA transcription factor encoded by the SRY gene on the Y chromosome in mammals. This protein initiates male...
- Sexual dimorphismThe condition where males and females of the same species exhibit distinct differences in appearance, size...
- Sexual maturationThe biological process by which an organism develops the ability to reproduce sexually, involving the...
- Sexual maturityThe stage of development when an organism becomes capable of reproduction. This involves the maturation of...
- Sexual reproductionA biological process that involves the fusion of gametes, typically from two parents, to produce offspring...
- Sexual selectionA mode of natural selection in which individuals with certain inherited characteristics are more likely than...
- Sexually dimorphic nucleusA distinct cluster of cells located in the preoptic area of the hypothalamus that shows a marked size...
- ShakeoffA process in which an atom undergoing an inner-shell ionization event simultaneously ejects an outer-shell...
- ShakeupA process accompanying an inner-shell ionization event where an outer-shell electron is simultaneously...
- Shallow trapA localized energy state within a material that can temporarily capture charge carriers, such as electrons or...
- Shannon-Wiener diversity indexA quantitative measure used in ecology to assess the biodiversity of a community, taking into account both...
- Shape selectivityThe influence of the pore structure of a catalyst or molecular sieve on the overall reaction, dictating which...
- Shape-memory polymerA polymeric material capable of recovering its original shape from a temporary, deformed shape upon exposure...
- Shear dependent viscosityA characteristic of non-Newtonian fluids where the apparent viscosity changes with the applied shear rate...
- Shear modulusA measure of a material's resistance to being deformed by shear stress, also known as the modulus of...
- Shear rateThe rate at which a fluid is sheared or deformed, defined as the velocity gradient perpendicular to the...
- Shear strainA measure of the deformation of a material under shear stress, representing the angular displacement of a...
- Shear stressA force acting tangentially to a surface per unit area, causing deformation by sliding layers of material...
- Shear thinningA rheological behavior observed in non-Newtonian fluids where the apparent viscosity decreases as the shear...
- Shear transitionA type of solid-state phase transformation that involves a cooperative movement of atoms or molecules...
- Shear viscosityA measure of a fluid's resistance to flow when subjected to shear stress, quantifying the internal friction...
- Sheath flow interfaceAn interface for mass spectrometry where the analyte solution exiting a capillary is surrounded by a coaxial...
- Sheath gasA gas, often nitrogen, used in electrospray ionization mass spectrometry to assist in the nebulization of the...
- Sheath liquidA conductive liquid that flows concentrically around the sample stream in a sheath flow electrospray...
- Sheep red blood cell antigenA foreign substance present on the surface of sheep red blood cells that can elicit an immune response when...
- Shelf lifeThe period during which a material, such as a reagent or reference material, retains its specified properties...
- Shelford’s law of toleranceA principle in ecology stating that the distribution and abundance of a species are limited by the range of...
- Shell-crosslinked micelleAn aggregate formed by amphiphilic block copolymers in a selective solvent, where the outer shell of the...
- Shellfish poisoningA group of illnesses caused by consuming shellfish that have accumulated toxins produced by certain marine...
- Shewhart control chartA statistical process control tool used to monitor the stability and performance of an analytical measurement...
- Shewhart control limitA statistical boundary on a control chart, calculated from process data, used to monitor the stability and...
- Shewhart means chartA type of Shewhart control chart used to monitor the central tendency of a process by plotting the means of...
- Shewhart range chartA type of Shewhart control chart that monitors the variability or dispersion of a process by plotting the...
- ShieldingThe phenomenon in nuclear magnetic resonance (NMR) spectroscopy where the electron cloud surrounding a...
- Shielding constantA dimensionless quantity that describes the reduction in the effective magnetic field experienced by an...
- Shift factorA parameter used in time-temperature superposition to relate the viscoelastic response of a polymer at one...
- Shift reagentA paramagnetic substance, usually a lanthanide complex such as Eu(fod)3 or Eu(dpm)3, that binds to polar...
- Shirley backgroundA method for subtracting the inelastic background from X-ray photoelectron spectroscopy (XPS) spectra. It...
- Shish-kebab structureA distinctive morphology observed in semicrystalline polymers, particularly after crystallization under flow...
- Short chainA polymer chain with a relatively low number of repeating monomer units, resulting in a low relative...
- Short circuit photocurrentThe electric current generated by a photovoltaic device when its terminals are connected directly, resulting...
- Short-range intramolecular interactionsForces acting between atoms or groups of atoms within the same polymer molecule that are separated by a small...
- Short-term exposure limitThe maximum concentration of a hazardous substance to which a worker can be exposed for a continuous...
- Shot noiseA type of electronic noise that arises from the discrete nature of charge carriers, such as electrons or...
- Shotgun lipidomicsAn analytical approach in lipidomics that involves the direct analysis of total lipid extracts without prior...
- Shotgun methodA strategy for determining the base sequence of long DNA in which the DNA is broken at random into many small...
- Shotgun proteomicsA method for identifying and quantifying proteins in a complex biological sample by first digesting the...
- Shots per pixelThe count of primary ion pulses landing on each image pixel during a single scan of the raster in SIMS...
- ShrinkageThe reduction in volume or linear dimensions of a material, often observed during processing or curing of...
- ShuntA bypass or diversion of fluid, such as blood or cerebrospinal fluid, from one part of the body to another...
- Shut-down stateA condition of an automated analytical system where it is not operating and is prepared for a prolonged...
- Shut-down timeThe duration required for an automated analytical system to transition from an operational state to a...
- Shuttle vectorA type of plasmid or viral vector that can replicate in at least two different host organisms, typically a...
- SIThe International System of Units, a coherent system of units built upon seven base units: meter, kilogram...
- SialonA ceramic based on the silicon-aluminium-oxygen-nitrogen system, formed as a solid solution in which...
- SiblingOne of two or more individuals born to the same pair of parents, in contrast to a half-sibling, who shares...
- Sick building syndromeA condition in which occupants of a specific building experience acute health and comfort effects that appear...
- Side group or side-chain polymer liquid crystalA type of polymer liquid crystal where the mesogenic units, which are responsible for liquid crystalline...
- Side-chain macromolecular rotaxaneA macromolecular rotaxane where the rotaxane constitutional unit is attached as a side chain to a polymer...
- Side-chain rotaxane polymerA polymer in which rotaxane units are incorporated as pendant groups along the main polymer backbone. Each...
- Side-chain self-assemblyThe spontaneous organization of polymer side chains into ordered, discrete, non-covalently bonded...
- Side-effectAn unintended and often undesirable effect of a therapeutic agent or intervention, occurring in addition to...
- SiderosisA form of pneumoconiosis resulting from the inhalation and deposition of iron-containing dust, such as iron...
- Sidestream smokeThe smoke emitted from the burning end of a cigarette, cigar, or pipe, distinct from the mainstream smoke...
- SiemensThe SI derived unit for electric conductance, representing the reciprocal of electrical resistance. One...
- SievertThe SI derived unit of dose equivalent, representing the stochastic health effect of low doses of ionizing...
- Sieverts’ lawA relation under which the concentration of a diatomic gas dissolved in a metal varies as the square root of...
- SievingA mechanical process used to separate particles of different sizes by passing them through a mesh or screen...
- Sigmatropic rearrangementA pericyclic reaction involving the concerted migration of a sigma bond across a conjugated pi system...
- SignAn objective indication of a disease or health condition that can be observed or measured by a healthcare...
- SignalA measurable physical quantity, such as an electrical current, voltage, or light intensity, that carries...
- Signal peptideA short, N-terminal amino acid sequence present in many newly synthesized proteins that directs them to...
- Signal transducer and activator of transcriptionA class of intracellular proteins that mediate cellular responses to cytokines and growth factors. Upon...
- Signal transductionThe process by which a cell converts an extracellular signal into an intracellular response. This involves a...
- Signaling lectinA carbohydrate-binding protein that, upon binding to a specific sugar structure on a cell surface or another...
- Signalling lipidsLipid molecules that act as messengers within or between cells, initiating or modulating cellular responses...
- Signal-to-noise ratioThe ratio of the amplitude of a desired analytical signal to the amplitude of the background noise in a...
- SilanesCompounds consisting of silicon and hydrogen atoms, analogous to alkanes but with silicon replacing carbon in...
- SilanolsOrganic compounds containing one or more hydroxyl groups directly bonded to a silicon atom. They are the...
- SilasesquiazanesPolymeric compounds containing silicon, nitrogen, and hydrogen, characterized by a three-dimensional network...
- SilasesquioxanesPolyhedral oligomeric silsesquioxanes (POSS) are cage-like organosilicon compounds with the general formula...
- SilasesquithianesPolymeric compounds containing silicon and sulfur, characterized by a three-dimensional network structure...
- SilathianesOrganic compounds characterized by the presence of silicon-sulfur bonds, forming a chain or ring structure...
- SilazanesCompounds containing silicon-nitrogen bonds, where the silicon atoms are bonded to at least one nitrogen...
- SiliconesPolymeric compounds containing repeating siloxane (-Si-O-) units in their backbone, with organic groups...
- SilicosisA chronic, progressive lung disease caused by the inhalation of crystalline silica dust, leading to...
- SiltFine-grained particulate matter, larger than clay but smaller than sand, typically found in soil and...
- Silver electrodeAn electrode constructed from silver metal, frequently used as a reference electrode or an indicator...
- Silver filmA thin transparent film, such as a liquid soap film, whose thickness is of the order of 100 nanometres, so...
- Silver stainingA histological technique that uses silver ions to visualize specific cellular components, such as proteins...
- Silyl groupsFunctional groups derived from silane (SiH4) by the removal of one or more hydrogen atoms. The simplest silyl...
- Silyl radicalsMolecular entities containing an unpaired electron localized primarily on a silicon atom. These highly...
- SilylationA chemical reaction that introduces silicon-containing groups, specifically silyl groups, into a molecule or...
- SilyleneA neutral, divalent silicon compound with the general formula R2Si, containing a silicon atom with only two...
- Similarity ensemble approachA computational method for predicting new biological targets for a molecule of interest by comparing it to...
- Similarity indexA quantitative measure of the resemblance between two objects or datasets, often used in chemometrics to...
- Similarity searchingA computational technique used in cheminformatics to find molecules in a database that are structurally...
- Simple reaction time testA neurobehavioral assessment that measures the time taken for an individual to respond to a single...
- Simple shearA type of deformation where parallel planes within a material slide past one another, with the displacement...
- Simple-to-use interactive self-modelling mixture analysisA chemometric technique designed for the analysis of multicomponent mixtures where the pure component spectra...
- Simplified molecular input line entry systemA chemical notation system that represents molecular structures using short ASCII strings, allowing for...
- Simpson’s diversity indexA measure of community diversity based on the probability that two individuals drawn at random belong to the...
- SIMS ion imageA two-dimensional spatial distribution map of specific secondary ions generated from a sample surface during...
- Simulated field studiesEcological investigations conducted in controlled outdoor environments that mimic natural conditions to...
- Simulation techniqueA technique for compensating interference errors by preparing reference solutions whose quantitative...
- Simulation testAn experimental procedure designed to mimic real-world conditions or processes to evaluate the behavior or...
- Simultaneous interpenetrating polymer networkA polymer blend composed of two or more polymer networks that are synthesized and/or crosslinked...
- Simultaneous pair transitionsA process in which two or more atoms or molecules simultaneously absorb a single photon, leading to the...
- Simultaneous reactionsTwo or more chemical reactions occurring concurrently within the same reaction vessel or system. These...
- Simultaneous semi-interpenetrating polymer networkA polymer blend comprising at least one polymer network and at least one linear or branched polymer, where...
- Simultaneous spectrometerAn analytical instrument designed to measure multiple wavelengths or spectral regions concurrently. This type...
- Simultaneous steam distillation-solvent extractionA combined extraction technique that simultaneously performs steam distillation and solvent extraction to...
- Simultaneous techniqueA method in thermal analysis where two or more different thermal analysis techniques are applied to the same...
- Single beam spectrumA measurement of the intensity of radiation transmitted through or reflected from a sample, recorded as a...
- Single crystal nuclear magnetic resonance spectroscopyA specialized nuclear magnetic resonance (NMR) technique that examines the anisotropic properties of nuclear...
- Single escape peakA peak observed in a gamma-ray spectrum that results from the escape of one of the two 0.511 MeV annihilation...
- Single linkageA hierarchical clustering method where the distance between two clusters is defined as the minimum distance...
- Single nucleotide polymorphismA variation in a single nucleotide base pair at a specific position in the deoxyribonucleic acid (DNA)...
- Single scatteringThe process where a photon or particle interacts with only one scattering center within a medium before being...
- Single-beam spectrometerAn optical instrument that directs a single beam of radiation through a sample to measure its absorbance or...
- Single-chain antibodyA recombinant antibody fragment consisting of the variable regions of the heavy and light chains connected by...
- Single-drop microextractionA microextraction technique where a small drop of an immiscible organic solvent is suspended at the tip of a...
- Single-electron transfer mechanismA reaction pathway in which one of the elementary steps involves the transfer of a single electron from an...
- Single-focusing mass spectrometerA mass spectrometer in which a single magnetic sector brings ions of one mass-to-charge ratio to a focus even...
- Single-photon timingA highly sensitive technique used to measure the time-resolved fluorescence decay of a sample by detecting...
- Single-step reactionA reaction in which the reactants are converted directly into products via one transition state, with no...
- Single-strand chainA polymer chain in which each constitutional unit is connected to at most two other constitutional units...
- Single-strand macromoleculeA macromolecule whose constitutional units are joined to their neighbours through a single pair of atoms, one...
- Single-strand polymerA polymer whose molecules consist of constitutional units connected in such a way that adjacent units are...
- Singlet molecular oxygenAn excited state of molecular oxygen (O2) in which all electrons are spin-paired, resulting in a total spin...
- Singlet stateAn electronic state of an atom or molecule where all electron spins are paired, resulting in a total spin...
- Singlet-singlet absorptionThe process where a molecule in its ground electronic singlet state absorbs a photon and transitions to an...
- Singlet-singlet energy transferA process where electronic excitation energy is transferred from a donor molecule in its excited singlet...
- Singlet-triplet absorptionThe process where a molecule in its ground electronic singlet state absorbs a photon and transitions to an...
- Singlet-triplet crossingA point or seam in nuclear coordinate space where the potential energy surfaces of a singlet state and a...
- Singlet-triplet energy transferThe transfer of excitation energy from an excited singlet donor to an acceptor that ends up in an excited...
- Singly labelledDescribing a chemical compound in which only one specific atom of a particular element has been replaced by...
- Singular value decompositionA matrix factorization technique that decomposes a matrix into three simpler matrices: a unitary matrix, a...
- SinkA process, activity, or medium that removes a chemical species from a specific part of the environment, such...
- Sinoatrial nodeA specialized cluster of myocardial cells located in the wall of the right atrium of the heart, near the...
- SinteringA process of consolidating particulate materials into a solid or porous mass by heating them to a temperature...
- SinusA cavity or hollow space within a bone or other tissue, or a dilated channel for venous blood. These...
- Sinus venosusA thin-walled, sac-like structure in the embryonic heart that receives venous blood from the body and yolk...
- Sister chromatid exchangeA reciprocal interchange of DNA segments between two identical sister chromatids of a duplicated chromosome...
- Site splittingA splitting of a spectral band into two or more components in a crystal, where the same transition of the...
- Site-directed mutagenesisA molecular biology technique used to introduce specific, intentional changes to the DNA sequence of a gene...
- Situs inversusA congenital condition characterized by the complete or partial reversal of the major visceral organs from...
- Size effectThe phenomenon where the physical or chemical properties of a material change significantly as its dimensions...
1,437 of 13,676 terms in Chemistry terminology (MLC-0109). Request the full dataset.