Metastable set

Update the Metastable set Compute the saturation ratio vector S and update the metastable set ... 

A feed composition in the metastable set is stable to infinitesimal composition disturbances but is unstable to finite ones hence, for such a composition phase splitting can only occur by nucleation, and not simply by Brownian motion (which, at most, supposedly results in infinitesimal composition disturbances). Hence, a metastable composition may be observed as a one-phase system in the laboratory Superheated liquids and subcooled vapors are elementary one-component examples. In contrast with this, one-phase spinodal compositions, by virtue of being unstable to infinitesimal perturbations, will never be observed in the laboratory. 

Fig. 4. Ramachandran plots of the five 1 pairs colored according to the associated metastable sets. The numbers of metastable sets differ for different pairs (it is from left to right 5,4,5,4,4)...

It is instructive to compare the eigenvalues of transition matrices obtained for different lag times t. That is, we do not count transitions on a timescale of O.lps which means to observe transitions from one instance of the time series to the next, but count transitions on a timescale of, say, ps which is between every tenth step in the global Viterbi path. For all time lags. Fig. 5 clearly indicates two dominant eigenvalues after which we find a gap, followed by other gaps after 4, 9, or 16 eigenvalues. This yields 2, respectively 4, 9, or 16 metastable sets. To avoid confusion we call these metastable sets (molecular) conformations. 

C. Schiitte and W. Huisinga (2003) Biomolecular conformations can be identified as metastable sets of molecular dynamics. In Handbook of Numerical Analysis (P. G. Ciaret and J.-L. Lions, eds.). Computational Chemistry, North-Holland... 

Norma ions (m, or formed in the ion source will pass (filter) through the first, second, and third quadrupoles (Ql, 2, 3) if these are set correctly. If Ql is set to pass only m, ions, then normal mj ions cannot reach the detector, and if Q3 is set to pass only mj ions, then m + ions cannot reach the detector. Any mj ions that reach the detector must have been formed (metastable or induced by collision) by dissociation of m,+ ions in Q2. 

Modem mass spectrometers are set to transmit and measure normal ions but, under normal circumstances, the metastable ones are not recorded. 

The interpretation of metastable phases in terms of Gibbsian thermodynamics is set out simply in a paper by van den Broek and Dirks (1987). 

The method of false transients cannot be used to find a metastable steady state. Instead, it is necessary to solve the algebraic equations that result from setting the derivatives equal to zero in Equations (5.29) and (5.30). This is easy in the current example since Equation (5.29) (with daout/dr = Q) can be solved for Uout- The result is substituted into Equation (5.30) (with dTout/dt = Q) to obtain a single equation in a single unknown. The three solutions are... 

It is a well-known fact that substances like water and acetic acid can be cooled below the breezing point in this condition they are said to be supercooled (compare supersaturated solution). Such supercooled substances have vapour pressures which change in a normal manner with temperature the vapour pressme curve is represented by the dotted line MU—a continuation of ML. The curve ML lies above the vapour pressure curve of the solid and it is apparent that the vapour pressure of the supersaturated liquid is greater than that of the soUd. The supercooled liquid is in a condition of metastability. As soon as crystallisation sets in, the temperatiure rises to the true freezing or melting point. It will be observed that no dotted continuation of the vapour pressure curve of the solid is shown this would mean a suspended transformation in the change from the solid to the liquid state. Such a change has not been observed nor is it theoretically possible. 

Fig. 5.19. Experimental set-up to study the influence of metastable atoms of rare gases on electrical conductivity of Au/ZnO films [160]...

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