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Experimental Correlations

In practical application, the Mott VRH model is found to be widely applied to moderate doping levels and moderate temperatures for all CPs, whilst for high doping levels, the Sheng model (or variations thereof) is found to work reasonably well. The Kivelson model is applied in a very limited sense to P(Ac) within narrow doping and temperature limits as described above. We now discuss some experimental correlations. [Pg.155]


The highly detailed results obtained for the neat ionic liquid [BMIM][PFg] clearly demonstrate the potential of this method for determination of molecular reorienta-tional dynamics in ionic liquids. Further studies should combine the results for the reorientational dynamics with viscosity data in order to compare experimental correlation times with correlation times calculated from hydrodynamic models (cf [14]). It should thus be possible to draw conclusions about the intermolecular structure and interactions in ionic liquids and about the molecular basis of specific properties of ionic liquids. [Pg.173]

In their study of the effect of particle-size distribution on mass-transfer in dispersions, Gal-Or and Hoelscher (G5) show that when the variable particle size is replaced by the surface mean radius a32, the error introduced is usually very small (see Section IV, J). Consequently if a in Eq. (144) is replaced by a32, that equation can be compared with the experimental correlations [Eq. (10) and (11)] proposed by Calderbank and Moo-Young (C4) for mass transfer in dispersions (see Fig. 9). [Pg.348]

Experimental correlations have been established in a given LDL formulation between foam stability and interfacial tension [33]. For example, Fig. 15 shows the effect of increasing water hardness on plate washing performance of an LAS/AES blend. A small amount of Ca2+ ion helps substantially to stabilize the foam. Under the same conditions interfacial tension is also lowered substantially. The two curves show an inverse relationship where the minimum interfacial tension value corresponds to the optimum level of foam stability as measured by plate washing [33]. [Pg.128]

The details of the specific features of the heat transfer coefficient, and pressure drop estimation have been covered throughout the previous chapters. The objective of this chapter is to summarize important theoretical solutions, results of numerical calculations and experimental correlations that are common in micro-channel devices. These results are assessed from the practical point of view so that they provide a sound basis and guidelines for the evaluation of heat transfer and pressure drop characteristics of single-phase gas-liquid and steam-liquid flows. [Pg.329]

The coalescence constant required experimental correlation with the agitation rate and the surface free energies of the polymer particles. [Pg.272]

Steady State Population Density Distributions. Representative experimental population density distri-butions are presented by Figure 1 for two different levels of media viscosity. An excellent degree of theoretical (Equation 8) / experimental correlation is observed. Inasmuch as the slope of population density distribution at a specific degree of polymerization is proportional to the rate of propagation for that size macroanion, propagation rates are also observed to be independent of molecular weight. [Pg.382]

The high velocities in the Ekman layers and the thinness of the layers strongly enhance the heat transfer between the gas and the sidewalls. There exist a variety of well-esfablished analytical and experimental correlations for fhe heaf fransfer between gas and a rotating disc (or the wall of fhe vessel). Cobb and Saunders [15] correlated their experimental investigations of fhe average laminar heaf fransfer with the Reynolds number Re = < 2.4 x lO ... [Pg.132]

Geihng E, Cannon P. Pathogenic effects of elixir of sulfanilamide (diethylene glycol) poisoning. A clinical and experimental correlation. Final report. Journal of the American Medical Association, 1938,111 919-926. [Pg.138]

Ideally, a mathematical model would link yields and/or product properties with process variables in terms of fundamental process phenomena only. All model parameters would be taken from existing theories and there would be no need for adjusting parameters. Such models would be the most powerful at extrapolating results from small scale to a full process scale. The models with which we deal in practice do never reflect all the microscopic details of all phenomena composing the process. Therefore, experimental correlations for model parameters are used and/or parameters are evaluated by fitting the calculated process performance to that observed. [Pg.232]

Both enthalpy and entropy can be calculated from an equation of state to predict the deviation from ideal gas behavior. Having calculated the ideal gas enthalpy or entropy from experimentally correlated data, the enthalpy or entropy departure function from the reference state can then be calculated from an equation of state. [Pg.74]

The structures of the new bicyclic peroxides have been established by the usual combination of physical techniques and chemical transformations. Here we highlight features of the H and 13C n.m.r. spectroscopic data that provide the best characterization of these compounds their reactions are discussed later. Information about the C-O-O-C dihedral angle in organic peroxides is potentially available from photoelectron (PE) spectroscopy. Measurements on comparatively rigid systems play an important part in establishing a soundly based experimental correlation, and the results obtained on several of these bicyclic peroxides are presented in this section also. [Pg.149]

We shall retain this assumption even for the high-temperature combustion case, realizing that it is quite severe. However, its neglect will undoubtedly be compensated through ultimate experimental correlations. With assumption 7 we approximate... [Pg.305]

More specific results are beyond the scope of our limited presentation for plumes. However, we will examine some gross features of transient plumes namely (a) the rise of a starting plume and (b) the dynamics of a fire ball due to the sudden release of a finite burst of gaseous fuel. Again, our philosophy here is not to develop exact solutions, but to represent the relevant physics through approximate analyses. In this way, experimental correlations for the phenomena can be better appreciated. [Pg.326]

Table 45.2 Examples of experimental correlations for hydrogen solubility. Table 45.2 Examples of experimental correlations for hydrogen solubility.
A significant merit of the dispersion model is some experimental correlations for the Peclet number. There are no such direct correlations for the parameters of the Gamma or Gaussian or other similar models. [Pg.512]

Table 4.16. Analytical and Experimental Correlations for Metal Droplet Sizes in Gas Atomization via Film or Sheet Breakup... Table 4.16. Analytical and Experimental Correlations for Metal Droplet Sizes in Gas Atomization via Film or Sheet Breakup...
In a supersonic gas flow, the convective heat transfer coefficient is not only a function of the Reynolds and Prandtl numbers, but also depends on the droplet surface temperature and the Mach number (compressibility of gas). 154 156 However, the effects of the surface temperature and the Mach number may be substantially eliminated if all properties are evaluated at a film temperature defined in Ref. 623. Thus, the convective heat transfer coefficient may still be estimated using the experimental correlation proposed by Ranz and Marshall 505 with appropriate modifications to account for various effects such as turbulence,[587] droplet oscillation and distortion,[5851 and droplet vaporization and mass transfer. 555 It has been demonstrated 1561 that using the modified Newton s law of cooling and evaluating the heat transfer coefficient at the film temperature allow numerical calculations of droplet cooling and solidification histories in both subsonic and supersonic gas flows in the spray. [Pg.372]

Although the agreement between calculated and experimental correlation and total energies is reassuring, as chemists we are more interested in relative quantities. Let us therefore turn our attention to AEs. In Table 1.9, we compare the calculated all-electron CCSD(T) equilibrium AEs with the corresponding AEs derived from experimental data, see Ref. 9. [Pg.21]

Here, gt takes into account one interesting feature of the free radical polymerization kinetics the auto acceleration in the rate of reaction (better known as the Trommsdorff or gel effect). The gel effect is taken into account in the model (42) by including the experimental correlation developed in [18] for the termination rate ... [Pg.104]

Detonation Wave, Elastic. An elastic wave is one which temporarily disturbs the medium thru which it traverses ie, after passage of the wave, the medium returns to its original state. Properties of elastic waves and of plastic waves were determined by Minshall (Ref 39) using pin contactors and crystals. Nawa (Ref 85) carried out theoretical and exptl studies on the transition of the energy generated by expls and the wave shapes of the generated elastic waves. The amplitude of an elastic wave was theoretically detd and experimentally correlated with sp energy and/or brisance of expls (See also Ref 92a)... [Pg.684]

Compared to other models (e.g., Voigt-Reuss, Halpin-Tsai, modified mixture law, and Cox), the dilute suspension of clusters model promulgated by Villoria and Miravete [255] could estimate the influence of the dispersion of nanofillers in nanocomposite Young s modulus with much improved theoretical-experimental correlation. [Pg.76]

In discussing experimental correlation functions, it is convenient to define the normalized function... [Pg.42]

In the following we focus our attention on approximate velocity and angular momentum autocorrelation functions generated from postulated memory functions. The theory behind these approximations has been outlined previously in this section. Each of the proposed memory functions that we shall consider has already been discussed in the previous sections. Here we examine how well the time-correlation functions generated from these postulated memories reproduce our experimental correlation functions and spectra. It is also informative to see the relationships between the postulated and experimental memories for our systems. [Pg.120]


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