Gold Book Terms - M

E/2 mass spectrum M machine  in analysismacrocycle macrolides macrometeorology  in atmospheric chemistrymacromolecular macromolecular isomorphism macromolecule macromonomer macromonomer molecule macromonomer unit macromonomeric unit macropore  in catalysismacroporous polymer macroradical macroscopic cross-section macroscopic diffusion control macroscopic film macroscopic kinetics magic acid magic angle magnetic circular dichroism magnetic coherence length \(\xi_{\text{M}}\)magnetic deflection  in mass spectrometrymagnetic equivalence magnetic field (B) scan  in mass spectrometrymagnetic field strength \(H\)magnetic flux density  in Mössbauer spectroscopymagnetic flux density \(B\)magnetic flux \(\mathit{\Phi}\)magnetic induction magnetic moment \(m\),\(\mu\)magnetic resonance imaging magnetic susceptibility magnetic susceptibility \(\chi\)magnetic transition magnetizability \(\xi\)magnetization transfer magnetogyric ratio \(\gamma\)main chain (backbone)  of a polymermain-chain polymer liquid crystal main-chain scission mancude-ring systems mancunide-ring systems manipulator manual  in analysismapping  in biotechnologyMarangoni effect Marcus equation (for electron transfer) Marcus inverted region (for electron transfer) Marcus–Coltrin path Marcus–Hush relationship Mark–Houwink equation marker Markownikoff rule martensitic transition mass (weight) of the stationary phase \(W_{\text{s}}\) in chromatographymass analysis  in mass spectrometrymass balance  in atmospheric chemistrymass concentration \(\gamma\),\(\rho\)mass density mass density gradient \(\bigtriangledown \rho\),\(\text{grad}\: \rho\)mass distribution ratio mass distribution ratio  in chromatographymass distribution ratio \(k_{\text{MEEKC}}\) in micro-emulsion electrokinetic chromatographymass distribution ratio \(k_{\text{MEKC}}\) in micellar electrokinetic chromatographymass excess \(\mathit{\Delta}\)mass flow rate \(q_{\text{m}}\)mass fraction \(w\)mass number \(A\)mass peak  in mass spectrometrymass range  in mass spectrometrymass resolving power  in mass spectrometrymass spectrograph mass spectrometer mass spectrometer (operating on the linear accelerator principle) mass spectrometer focusing system (deflection system) mass spectrometric detector  in gas chromatographymass spectrometry mass spectroscope mass spectroscopy mass spectrum mass transfer coefficient  in electrochemistrymass transfer  in biotechnologymass-average velocity  in electrolytesmass-distribution function mass-flow sensitive detector  in chromatographymass-law effect mass-to-charge ratio \(m_{\text{z}}\) in mass spectrometrymass-transfer-controlled electrolyte rate constant mass \(m\)massic massive transition matched cells  in spectrochemical analysismaterial safety data sheet matrix effect  in surface analysismatrix  in analysismatrix isolation Mattauch–Herzog geometry maximum allowable concentration  in atmospheric chemistrymaximum emission concentration  in atmospheric chemistrymaximum hardness, principle of maximum latent period maximum loading maximum permissible daily dose maximum permissible level maximum storage life maximum tolerable concentration maximum tolerable dose maximum tolerable exposure level maximum tolerated dose McLafferty rearrangement  in mass spectrometrymean \(\bar{x}\)mean activity of an electrolyte in solution  in mass spectrometrymean catalytic activity rate \(\frac{\Delta z}{\Delta t}\)mean current density mean exchange current density mean free path \(\lambda\)mean interstitial velocity of the carrier gas  in chromatographymean life \(\tau\)mean lifetime \(\tau\)mean linear range  in nuclear chemistrymean mass range  in nuclear chemistrymean mass rate \(\frac{\Delta m}{\Delta t}\)mean residence time  of adsorbed moleculesmean substance rate \(\frac{\Delta n}{\Delta t}\)mean volume rate \(\frac{\Delta V}{\Delta t}\)measurable quantity measurand measured excitation spectrum measured spectrum measured value  in analysismeasurement measurement resolution  in atmospheric trace component analysismeasurement result measurement solution  in analysismeasurement threshold  of an analysermechanical entrapment mechanical hygrometer mechanical inhibitor mechanism  of a reactionmechanism-based inhibition mechanization  in analysisMechano-chemical reaction median median effective concentration \(\text{EC}_{50}\)median effective dose \(\text{ED}_{50}\)median lethal concentration \(\text{LC}_{50}\)median lethal dose \(\text{LD}_{50}\)median lethal time \(\text{TL}_{50}\)median narcotic concentration \(\text{NC}_{50}\)median narcotic dose \(\text{ND}_{50}\)medium medium effect medium-pressure mercury lamp mega meiosis Meisenheimer adduct Meker burner melting melting point (corrected/uncorrected) membrane membrane emf membrane  in an ion-selective electrodemembrane potential membrane sites  in an ion-selective electrodememory effect  in atmospheric chemistrymer mer-  in inorganic nomenclaturemercaptals mercaptans mercaptides mercaptoles mercury flow system  in spectrochemical analysismercury–xenon lamp mero merry-go-round reactor meso meso structures  in polymersmeso-compound mesogen mesogenic group mesogenic monomer mesogenic pitch mesoionic compounds mesolytic cleavage mesomeric effect mesomerism mesomorphic phase mesomorphic state mesomorphic transition mesopause  in atmospheric chemistrymesophase mesophase pitch mesophase pitch-based carbon fibres mesophiles mesopore  in catalysismesoscale mesosphere messenger RNA metabolic half-life metabolism metabolite metal distribution metal to ligand charge transfer (MLCT) transition metal to metal charge transfer (MMCT) transition metal–carbene complexes metal–carbyne complexes metal–insulator transition metal–nonmetal transition metallacycloalkanes metallocenes metalloenzyme metallurgical coke metamagnetic transition metastability metastable metastable film metastable ion  in mass spectrometrymetastable state  in nuclear chemistrymetastable state  in spectrochemistrymetatectoid reaction metathesis methanogens method of isotopic perturbation methylene methylidyne methylotrophic microorganisms metre \(\text{m}\)micellar catalysis micellar mass micellar solubilization micellar weight micelle micelle charge Michaelis constant \(K_{\text{m}}\)Michaelis–Menten kinetics Michaelis–Menten mechanism micro micro-network microbial leaching microcanonical rate constant microcanonical variational transition-state theory microcarrier  in biotechnologymicroclimatology microdomain morphology microelectrophoresis microfiltration microgel microheterogeneity  in biochemistrymicrometeorology microphotometer micropore filling  in catalysismicropore  in catalysismicropore volume  in catalysismicroporous carbon microscopic chemical event microscopic cross-section \(\sigma\)microscopic diffusion control microscopic electrophoresis microscopic film microscopic kinetics microscopic reversibility at equilibrium microsome microsyneresis middle atmosphere Mie scattering migration migration current migration time \(t_{\text{m}}\) in capillary electrophoresismigration time of micelles \(t_{\text{mc}}\) in micellar electrokinetic chromatographymigratory aptitude migratory insertion milli milligram equivalent of readability  of a precision balancemillimetre of mercury milling minimum consumption time \(t_{\text{min}}\) in flame emission and absorption spectrometryminimum density of states criterion minimum lethal concentration \(\text{LC}_{\text{min}}\)minimum lethal dose \(\text{LD}_{\text{min}}\)minimum-energy reaction path minus minute  of arcmiscibility miscibility gap mist  in atmospheric chemistrymitochondria mitosis mixed ceramic mixed control mixed crystal mixed energy release mixed indicator mixed labelled mixed potential mixing control mixing height  in atmospheric chemistrymixing  in analytical chemistrymixing ratio  in analytical chemistrymixture MLCT mobile adsorption mobile phase  in chromatographymobile-phase velocity \(u\) in chromatographymobility (general) mobility  in aerosol physicsmobility \(\mu\)Möbius aromaticity mode mode-locked laser model network moderation  in nuclear chemistrymoderator modified active solid  in chromatographymodified Arrhenius equation modified sample modifier  in solvent extractionmodulus of elasticity \(E\)Mohr amplification process  in analysismoiety MOL file format molal molality \(m\),\(b\)molar molar absorption coefficient \(\varepsilon\)molar absorptivity molar activity  in radiochemistrymolar average velocity molar conductivity molar refraction \(R\)molar-mass exclusion limit  in polymersmolarity mole mole fraction molecular anion molecular beams molecular cation molecular conformation  of a polymermolecular connectivity index molecular design molecular dynamics molecular dynamics  in drug designmolecular entity molecular formula molecular graph molecular graph theory molecular graphics molecular ion  in mass spectrometrymolecular kinetics molecular laser molecular mechanics calculation molecular metal molecular modeling molecular nucleation  in polymersmolecular orbital molecular orientation molecular rearrangement molecular Rydberg state molecular shape molecular sieve effect molecular spectra molecular weight molecular-weight exclusion limit  in polymersmolecularity molecule molfile molozonides moment of a force \(M\)moment of inertia \(I\),\(J\)momentum spectrum momentum \(p\)monitoring mono-energetic radiation monochromator monoclonal antibodies monodisperse medium monodisperse polymer monoisotopic mass spectrum monolayer monolayer capacity monolith monomer monomer molecule monomer unit monomeric unit monosaccharides monotectic reaction monotectoid reaction monotectoid temperature monoterpenes monoterpenoids monothioacetals monotropic transition Monte Carlo (MC), method of Monte Carlo study mordant More O'Ferrall–Jencks diagram Morin transition morphology morphology coarsening morphotropic transition Morse potential Mössbauer effect Mössbauer thickness  in Mössbauer spectroscopymost probable distribution (in macromolecular assemblies) Mott transition Mott–Hubbard transition MPP-based carbon fibres mucopolysaccharides Mulliken population analysis multi-centre bond multi-centre reaction multi-channel pulse height analyser multi-strand chain  in polymersmulti-strand macromolecule multicoat morphology multiconfiguration SCF method multident multienzyme multienzyme complex multienzyme polypeptide multilayer multilayer adsorption multilayer aggregate  in polymer crystalsmultiphase copolymer multiphoton absorption multiphoton ionization  in mass spectrometrymultiphoton process multiple inclusion morphology multiple ionization satellite multiple peak scanning  in mass spectrometrymultiple scattering multiple-pass cell  in spectrochemical analysismultiplex spectrometer multiplicative name multiplicity multiply labelled multipole line  in X-ray spectroscopymultireference configuration interaction multistage sampling multivariate statistics munchnones muonium mustard oils mustards mutagen mutagenesis mutarotation mutation mutation rate  in biotechnologymutual inductance \(M\)Myelin cylinders µ- (mu)  in inorganic nomenclature