Average absolution deviation

Defubed as the average absolute deviation of the four traction values from the mean. The range is determined by the type and condition of grass. ... 

Lee and Thodos expanded their earlier treatment of self-diffusivity to cover 58 substances and 975 data points, with an average absolute deviation of 5.26 percent. Their correlation is too involved to repeat here, but those interested should refer to the original paper. 

Umesi-Danner They developed an equation for nonaqueous solvents with nonpolar and polar solutes. In all, 258 points were involved in the regression. Rj is the radius of gyration in A of the component molecule, which has been tabulated by Passut and Danner for 250 compounds. The average absolute deviation was 16 percent, compared with 26 percent for the Wilke-Chang equation. 

Siddiqi-Lucas In an impressive empirical study, these authors examined 1275 organic liquid mixtures. Their equation yielded an average absolute deviation of 13.1 percent, which was less than that for the Wilke-Chang equation (17.8 percent). Note that this correlation does not encompass aqueous solutions those were examined and a separate correlation was proposed, which is discussed later. 

Siddiqi-Lucas These authors examined 658 aqueous liqiiid mixtures in an empirical study. They found an average absolute deviation of 19.7 percent. In contrast, the Wilke-Chang equation gave 35.0 percent and the Hayduk-Laudie correlation gave 30.4 percent. 

Riazi-Whitson They presented a generahzed correlation in terms of viscosity and molar density that was apphcable to both gases and liqmds. The average absolute deviation for gases was only about 8 percent, while for liquids it was 15 percent. Their expression relies on the Chapman-Enskog correlation [Eq. (5-194)] for the low-pressure diffusivity and the Stiel-Thodos correlation for low-pressure viscosity ... 

Vigne.s empirically correlated mixture diffusivity data for 12 binary mixtures. Later Ertl et al. evaluated 122 binary systems, which showed an average absolute deviation of only 7 percent. None of the latter systems, however, was veiy nonideal. 

Siddiqi-Lucas suggested that component volume fractions might be used to correlate the effects of concentration dependence. They found an average absolute deviation of 4.5 percent for nonpolar-nonpolar mixtures, 16.5 percent for polar-nonpolar mixtures, and 10.8 percent for polar-polar mixtures. 

One particular case of multicomponent diffusion that has been examined is the dilute diffusion of a solute in a homogeneous mixture (e.g., of A in B -h C). Umesi and Danner compared the three equations given below for 49 ternaiy systems. All three equations were equivalent, giving average absolute deviations of 25 percent. 

Based on 23 data points for 3 systems. Average absolute deviation 26%. Use with surface area of drop after detachment occurs, = velocity through nozzle <3 = iuterfacial tension. 

E] Average absolute deviation 11% for 20 data points for 3 systems. 

Stainless steel flat six-blade turbine. Tank had four baffles. Correlation recommended for ( ) < 0.06 [Ref. 156] a = 6( )/<, where d p is Sauter mean diameter when 33% mass transfer has occurred. dp = particle or drop diameter <3 = iuterfacial tension, N/m ( )= volume fraction dispersed phase a = iuterfacial volume, 1/m and k OiDf implies rigid drops. Negligible drop coalescence. Average absolute deviation—19.71%. Graphical comparison given by Ref. 153. ... 

Salters et al. (2002) have recently proposed an alternative expression for calculating D j and Dm in clinopyroxene as a function of crystal and melt composition. The expressions are calibrated on over 40 experimental determinations of Ehj and Dm- Salters et al. (2002) do not give values for the average absolute deviation. The full expressions (with 1 s.d. uncertainties in brackets) are ... 

Table 4.6. Geometries and NBO descriptors 0/MH2 and MH3 metal hydrides of the third transition series of various spin multiplicities (IS + I), illustrating the correlations of metal charge (Qu) with metal hybrid d character (%d, taken as the average of a and 3 hybrids for open-shell species), bond length (Ruw) and angle (9hmh)> and average absolute deviation (Dev. = average %mh — 90" ), from idealized covalent geometry...

R varies between 0.933 and 0.945, with average absolute deviations from experiment of 0.23 - 0.26 kcal/mole for AGSO vation covering ranges of 3.1 kcal/mole. Thus electrostatic interaction is important, but not in a site-specific manner. Strongly positive... 

R = 0.990, and the average absolute deviation is 0.065 in dry gelatin (range = 1.53) and 0.6 in wet (range = 13.8). The inverse dependence upon area, which promotes intermolecular attractions,... 

Once free energies of solvation are available, other solution properties can be determined, such as solute conformations, pKa values, electrode potentials, reaction energetics, etc.9 10 82 For example, Reynolds applied ab initio (HF and MP2) QM/MM approaches to computing the electrode potentials in water of a group of quinines 83 the average absolute deviations for the most stable conformations were 0.024 (HF) and 0.033 (MP2) volts, for a range of 0.322 volts. 

In a very extensive test of the SM5 method (a type of GBM), Hawkins et al. found the average absolute deviation in AGsoivation to be 0.38 kcal/mole for 260 molecular solutes in water and in 90 organic solvents 131 for ions in water, it was 3.8 kcal/mole, for experimental AGsolvation between -58 and -110 kcal/mole. Semiempirical quantum-mechanical procedures were used. 

Baik and Friesner used an SCRF procedure in conjunction with B3LYP density functional calculations to obtain electrode potentials for groups of aromatic molecules, metallocenes and transition metal complexes in four different solvents 132 the average absolute deviation was about 0.15 volts for a range of values of 3.82 volts. Saracino et al. computed pKa for a series of carboxylic acids with an average absolute deviation of 0.41 for pKa between 1.23 and 5.03.133... 

The correlation-based techniques can achieve as high levels of accuracy as the direct-interaction ones for example, the GIPF AG hydration have average absolute deviations from experiment, 0.27 kcal/mole (Section II.2.iii), as good or better than the SCRF AGhydration in Table 6. However the GIPF, LSER and TLSER cannot describe the effects of the solute and solvent upon each other, such as polarization of the former and disruption of the structure of the latter. 

Vs,mm and Vs are negative, this means that each term except e is promoting solvation. Equation (10) is one of the few GIPF relationships that include Vmin, the overall most negative value of the electrostatic potential. The correlation coefficient for Eq. (10) is R = 0.988 the average absolute deviation from experiment is 0.27 kcal/mole for AGsoivation values varying over 9.59 kcal/mole. 

Chapter 17 - Vapor-liquid equilibrium (VLE) data are important for designing and modeling of process equipments. Since it is not always possible to carry out experiments at all possible temperatures and pressures, generally thermodynamic models based on equations on state are used for estimation of VLE. In this paper, an alternate tool, i.e. the artificial neural network technique has been applied for estimation of VLE for the binary systems viz. tert-butanol+2-ethyl-l-hexanol and n-butanol+2-ethyl-l-hexanol. The temperature range in which these models are valid is 353.2-458.2K at atmospheric pressure. The average absolute deviation for the temperature output was in range 2-3.3% and for the activity coefficient was less than 0.009%. The results were then compared with experimental data. 

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