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Static phase, definition

In this definition [B], [C], [B] and [C] refer to the total concentrations of B and C in the mobile and static phases, rather than to individual ions or complex species. It will be seen that complexing or chelating agents can alter the distribution constants markedly, thus affecting the separation factor. [Pg.94]

Abstract The theoretical basis for the quantum time evolution of path integral centroid variables is described, as weU as the motivation for using these variables to study condensed phase quantum dynamics. The equihbrium centroid distribution is shown to be a well-defined distribution function in the canonical ensemble. A quantum mechanical quasi-density operator (QDO) can then be associated with each value of the distribution so that, upon the application of rigorous quantum mechanics, it can be used to provide an exact definition of both static and dynamical centroid variables. Various properties of the dynamical centroid variables can thus be defined and explored. Importantly, this perspective shows that the centroid constraint on the imaginary time paths introduces a non-stationarity in the equihbrium ensemble. This, in turn, can be proven to yield information on the correlations of spontaneous dynamical fluctuations. This exact formalism also leads to a derivation of Centroid Molecular Dynamics, as well as the basis for systematic improvements of that theory. [Pg.47]

The thermodynamic dead volume includes those static fractions of the mobile phase that have the same composition as the moving phase, and thus do not contribute to solute retention by differential interaction in a similar manner to those with the stationary phase. It is seen that, in contrast to the kinetic dead volume, which by definition can contain no static mobile phase, and as a consequence is independent of the solute chromatographed, the thermodynamic dead volume will vary from solute to solute depending on the size of the solute molecule (i.e. is dependent on both ( i )and (n). Moreover, the amount of the stationary phase accessible to the solute will also vary with the size of the molecule (i.e. is dependent on (%)). It follows, that for a given stationary phase, it is not possible to compare the retentive properties of one solute with those of another in thermodynamic terms, unless ( ), (n) and (fc) are known accurately for each solute. This is particularly important if the two solutes differ significantly in molecular volume. The experimental determination of ( ), (n) and( ) would be extremely difficult, if not impossible In practice, as it would be necessary to carry out a separate series of exclusion measurements for each solute which, at best, would be lengthy and tedious. [Pg.32]

In considering physicochemical equilibria, that is to say, if one is interested in the internal constitution of a system in equilibrium when changes of phase and chemical reactions are admitted, one introduces the constitutive coordinates this being the number of moles of the ith constituent Ct in the a th phase. The definitions of Equations (10) through (12) remain unaltered, for die nf do not enter into the description of the interaction of the system with its surroundings. Let an amount dnf of C be introduced quasi,statically into the a th phase of the system. The work done on K shall be fi dnt> The quantity fif so defined is the chemical potential of C, in die ct th phase. It is in general a function of all the coordinates of K. Then, identically. [Pg.1607]

Our theory is one of a progressive spiral involution of time toward a concrescence, rather than a theory of a static hierarchy of waves, eternally expressed on many levels. This is because the terminal positions in the King Wen wave naturally quantify as zero states. The natural consequence of this is that the terminal sections of an epoch do not contribute to the valuation assigned to lower levels of that particular section of the hierarchy. This results in a progressive drop of valuations toward the zero state as any epoch enters its terminal phase. Only in the situation of final concrescence does the valuation on all levels actually become zero. In fact, the quantified definition of absolute concrescence is that it is the zero point in the quantified wave-hierarchy. [Pg.127]

If the catalyst particles are not completely wetted by the liquid phase and the pores consequently not completely filled with liquid phase (static holdup gives some indication of whether this is the case or not), the situation is considerably more complex. In addition to being a function of the Thiele modulus, the catalytic effectiveness will now depend on the fraction of external wetting, rjcs, and the fraction of pore volume filled with liquid, rji. Dudokovic [M.P. Dudokovic, Amer. Inst. Chem. Eng. Jl., 23, 940 (1977)] proposed a reasonable approach that accounts for all three factors. If the reaction proceeds only on the catalyst surface effectively wetted by the liquid phase and components of the reaction mixture are nonvolatile, then one can in principle modify the definition of the Thiele modulus to... [Pg.645]

To define the iramiscible-liquid-segregation problem, the drop size range of the dispersed phase must be known or approximated. Weinstein and Middleman present drop correlations for pipeline contacting and static mixers while Coulaloglou and Tavlarides present correlations of liquid in liquid drop sizes for agitated vessels. All use the Sauter mean drop size definitions and involve use of the Weber number, a... [Pg.148]

Benoit Paul Emile Clapeyron (1799-1864) A French engineer and physicist and one of the founders of thermodynamics. In 1843, Clapeyron further developed the idea of a reversible process, already suggested by Carnot, and made a definitive statement of Carnot s principle, which is now known as the second law of thermodynamics. Clapeyron also worked on the characterization of perfect gases, the calculation of the statics of continuous beams, and on phase transitions, Eq. (3.1.45). [Pg.50]


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See also in sourсe #XX -- [ Pg.29 ]

See also in sourсe #XX -- [ Pg.29 ]




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Phase, definition

Static phase

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