Partition ratio defined

Commonly used forms of this rate equation are given in Table 16-12. For adsorption bed calculations with constant separation factor systems, somewhat improved predictions are obtainecl using correction factors i /, and / defined in Table 16-12 is the partition ratio defined by Eq. (16-25). 

K s = stripping section partition ratio, defined as equilibrium concentration of product solute in extraction solvent divided by that in wash solvent (Bancroft coordinates)... 

In addition to the TDI experiment, the partition ratio measures the TDI efficiency. Specifically, the partition ratio is the number of inactivation kinetic events (k nact) versus the number of substrate turnover events per unit enzyme (kcat) [161], Thus, the most potent partition ratio is zero. The most common experimental setup for determining the partition ratio is the titration method that increases the inhibitor concentration relative to a known amount of enzyme. After the incubations, a secondary incubation containing a probe substrate similar to the TDI experiment is used to define the remaining activity. For accurate determination of the partition ratio from the titration method, it is assumed that the inhibitor is 100% metabolized ... 

Distribution ratio is the total analytical concentration of a substance in the organic phase to its total analytical concentration in the aqueous phase, usually measured at equilibrium. Symbol D. D shall be defined and, preferably, specified by an index if the distribution of mercury is measured, the distribution ratio is written D(Hg) or The term partition ratio is not used for the distribution ratio. 

In the adsorption in batch (second case), the concentration of the fluid varies from its initial to the equilibrium concentration. The partition ratio is used to discriminate between these two cases, which for the case of the solid phase initially free from the solute, is defined as (Perry and Green, 1999 Ruthven, 1984)... 

The effective partition ratio, k, is defined as the ratio of the concentration in the solid being formed over the concentration in the bulk liquid. Therefore,... 

While the variability has been assessed for LAS, little is known for other surfactants. However, the variability of the log Kow-values of LAS indicates that Kow measurements yield conditional partition ratios rather than well defined partition coefficients. On thermodynamic grounds, the partition ratio for ionic surfactants is a parameter depending very much on the electrolyte composition of the aqueous medium and therefore cannot be viewed as a partition coefficient in the sense of Henry s law (Schwarzenbach et al. 1993). In addition, experimental determination of Kow of surfactants could yield erroneous results, due to the emulsifying action of the surfactants in the octanol-water system (Morall et al., 1997). 

A useful index of the propensity for an enzyme to undergo inactivation, as opposed to metabolite formation, is the partition ratio, r (28), defined as the ratio of the rate of metabolite formation to the rate of inactive enzyme formation. Thus, by combining Eqs. (1) and (5) ... 

The resolution (Rs) of compounds on capillary GC columns is a function of the column efficiency (N effective), the ability of the stationary phase to separate the compounds (separation factor, a), and the ratio of the amount of time the compounds spend in the stationary phase vs. the time the compounds spend in the carrier gas phase (partition ratio, k ). Resolution of two compounds can be defined by the equation ... 

An adaptation of the distribution constant defined in Equation (23-3) could be made for solutes in chromatojp-aphy. As in liquid-liquid extraction, however, solutes may be present in several chemical forms, and therefore a quantity analogous to the distribution ratio (Section 23-1), called the partition ratio, is preferred. The partition ratio must be a somewhat more broadly defined term than the distribution ratio in liquid-liquid extraction for two reasons. First, in chromatography, concentrations of solute in the two phases are usually unknown and may be unmeasurable, as when adsorption is important. Second, instead of the two phases being merely an aqueous phase and an immiscible organic solvent, in chromatography they can be any one of innumerable combinations of solid or liquid stationary phases and liquid or gas... 

On occasion the factor Vn is combined with the partition-ratio term to give a factor called number of effective plates, defined by kj( + k)] n. Hence... 

Segregation and partition ratios as defined in detail above. 

The segregation ratio, I, and partition ratios of chromium and nickel in the stainless and heat resistant steels are shown in figures 6.12 and 6.13. These ratios were defined in chapter 1 as follows ... 

A convenient measure of the tendency of a given chemical species to partition itself preferentially between liquid and vapor pliases is tire equilibrium ratio defined as ... 

An equilibrium or theoretical stage in liquid-liquid extraction, as defined earlier, is routinely utilized in laboratory procedures. A feed solution is contacted with a solvent to remove one or more of the solutes from the feed. This can be carried out in a separating funnel or, preferably, in an agitated vessel that can produce droplets about 1 mm in diameter. After agitation has stopped and the phases separate, the two clear liquid layers are isolated by decantation. The partition ratio can then be determined directly by measuring the concentration of solute in the extract and raffinate layers. (Additional discussion is given in Liquid-Liquid Equilibrium Experimental Meth-... 

R is the gas constant, Bn is the second virial coefficient for the probe, B13 is the mixed virial coefficient of the solute vapor and carrier gas, V is the partial molar volume of 1 at infinite dilution, P is the total pressure, and K is the equilibrium partition coefficient, defined as the ratio of concentration of solute in the stationary phase, q, to that in the gas phase, c, that is, K s q/c. 

The partition ratio kBl(k d + kB) defines the efficiency of product formation from the encounter complex (see also Section 3.7.4). For the limiting case k dobserved rate constant of reaction approaches the rate constant of diffusion, kx kd. In 1917, von Smoluchowski derived Equation 2.27 from Fick s first law of diffusion for the ideal case of large spherical solutes. 

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