metastable


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met·a·sta·ble

(met'ă-stā'bĕl),
1. Of uncertain stability; in a condition to pass into another phase when slightly disturbed, for example, water, when cooled below the freezing point may remain liquid but will immediately congeal if a piece of ice is added.
2. Denoting the excited condition of the nucleus of a radionuclide isomer that reaches a lower energy state by the process of isomeric transition decay without changing its atomic number or weight; for example, 99m43Tc → 9943Tc + γ.
[meta- + L. stabilis, stable]
References in periodicals archive ?
More precisely, we attempted to interpret the intermitted brain functioning in the phenomenal level, through specific irregularities of the metastable balance observed in the resting-state activity.
At the same time, within a metastable miscibility gap of salient nonequilibrium features, the viscosity rises and diffusion coefficient declines with the increase in undercooling [12].
There is neither a passive region nor a region of metastable pit growth as for stainless steels.
The use of DFT, to determine the influence of 21% Si in the FCC--TiN showed that the Ti--Si--N stoichiometric phase is at metastable equilibrium and there is high probability that the compound formed corresponds to an interstitial TiN alloy where Si atoms form [Si.sub.3][N.sub.4] as an amorphous matrix for TiN stable crystals.
Thus, the state of relatively stable or metastable equilibrium is defined as the state in which a system remains for a long period of time, and any slight disturbance causing the system to deviate from the metastable state does not result in the system passing into another state.
9,107,856 B2; GlaxoSmithKline, LLC, Wilmington, DE, has patented an alcohol-free dental appliance cleansing formulation which is applied as an appliance outside the wearer's mouth for at least about 60 seconds, and which is a metastable emulsion.
The technology platform synergistically combines physical vapor deposition techniques, together with the exploitation of metastable phase separation in a low-alkali borosilicate glass system, to produce atomically bonded optically transparent nanostructured glass coatings on wide variety of glass platforms.
Metastable oil shale ash concrete left in water saturated conditions underground is a potential threat to groundwater quality which is largely unknown at present.
Considering, the probability of occurrence of transition from state 3 to state 1 is more as compared either to that from state 3 to state 0 or from state 1 to state 0 and also, assuming total population inversion, the metastable population densities of thulium ion becomes:
(6) The latter are the experimental data one obtains for microscopic objects that interact with a macroscopic measuring apparatus prepared in a metastable state, for example, the Wilson cloud chamber and the Geiger counter.
The core of the technique is the analysis of metastable states and using them to simplify the computational problem.
yttrium-Oxide Partially Stabilised Zirconia (y-PSZ) is a fully tetragonal fine-grained zirconia ceramic material made of 100% small metastable tetragonal grains (y-TZP) after the addition of approximately 2 to 3 mol% yttrium oxide (y2O3) as a stabilizing agent.1