Size ratio parameter definition

In adsorption studies the size ratio parameter, n, is defined as the number of solvent molecules replaced from the adsorbed layer by one molecule of the adsorbate. This is a definition at a molecular level. An alternative definition of n as a purely thermodynamic quantity is given by the ratio... 

It is important to specify detectors independent of column parameters and of sample size. One parameter that does this is minimum detectable level, MDL. It is the "level" of sample in the detector at the maximum of the peak, when the signal-to-noise ratio is two. The term detectability is sometimes used for MDL. Variations of this definition are sometimes given which require the signal-to-noise ratio to be either one, three, or five. The parameter is also defined sometimes in terms of root-mean square (rms) noise. Peak-to-peak noise can be taken as six times rms noise. 

The 2.6 times difference between 8y and 8 leads to a large difference in flie volume fractions corresponding to the beginning of the boimdary layers overlap. The dilute case theory is valid for volume fractions smaller than flie critical volume fractions (py and cp. These critical voliune fractions are functions of the frequency and particle size. These parameters are conventionally defined from the condition that the shortest distance between particle surfaces is equal to 28y or 28. This definition yields the following expression for the ratio of the critical volume ffactions in aqueous dispersions ... 

To characterize a droplet size distribution, at least two parameters are typically necessary, i.e., a representative droplet diameter, (for example, mean droplet size) and a measure of droplet size range (for example, standard deviation or q). Many representative droplet diameters have been used in specifying distribution functions. The definitions of these diameters and the relevant relationships are summarized in Table 4.2. These relationships are derived on the basis of the Rosin-Rammler distribution function (Eq. 14), and the diameters are uniquely related to each other via the distribution parameter q in the Rosin-Rammler distribution function. Lefebvre 1 calculated the values of these diameters for q ranging from 1.2 to 4.0. The calculated results showed that Dpeak is always larger than SMD, and SMD is between 80% and 84% of Dpeak for many droplet generation processes for which 2left-hand side of Dpeak. The ratio MMD/SMD is... 

The major reason why a reduction of the particle size or column diameter is expected to lead to an increase of separation speed (resolution power per time unit) can be found in its effect to decrease r. Separation speed is often expressed in the analytical literature in terms of the number of theoretical plates N per time unit f (for a definition of N in terms of experimental parameters see Sect. 3.1.1). For zone dispersion due to lateral non-equilibrium, the ratio N/t will be in general inversely proportional to r [20] ... 

In the off-contact printing process, tiiis is arguably the most important parameter in the screen printer setup. If it is too large, the screen will rapidly lose tension and the print will lose definition. If it is too small, the tension on the screen during the print will not be sufficient to transfer the paste to the substrate. Referring to Figure 5.19, the magnitude of snap-off is dependent on the size of the screen, with a ratio of maximum screen dimension to snap-off of 200 1. A list of typical snap-off distances for a sample of standard-size screens is shown in Table 5.3. 

In their simulation Barrat and Boyer [38] gave a quantitative definition of the electrostatic blob. Using the model of the chain under tension they established the quantitative relation between the number of monomers n in a section and its size R(n). The electrostatic blob size was directly related to the prefactor of in the expression for the mean square section size (R(nf) = nb + r b lge. To verify the dependence of the blob size on the value of the coupling parameter uf Barrat and Boyer also calculated the ratio /b. This ratio varies between 1.45 and 0.92 when the value... 

Accuracy has to be carefully defined, particularly for a (drop or particle) population containing a range of sizes. Tlie simplest description is via some appropriate mean size such as the Sauter Mean Diameter (d32, particle with the same volume /surface area ratio as ensemble of particles, sphere equivalent) or the mass median diameter (dso, size below which lie 50% by weight of the sample). The next step is to consider a second parameter describing the width of the distribution. A simple definition is a dimensionless span,... 

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