Correlation intrinsic parameter

On the other hand, a more practical approach is to analyze the various parameters with respect to their influence on the anomalous multiplets. According to this procedure Li and Reid (1990) could show that taking into account only the parameters G410Aq, a pronounced improvement for the description of the 2H(2)n/2 multiplet of Nd3+ could be achieved. To study the dependence of correlation effects on the interatomic distances, Jayasankar et al. (1993) analyzed spectroscopic data for LaCbiNd3"1" at pressures up to 10 GPa. Using the superposition model, they could derive the distance dependences of the intrinsic parameters B4 —4... 

The reactivity indices method is based on the assumption of a direct correlation between the activation free energy of a process and some intrinsic parameters, called reactivity indices, related to the electronic properties of the heteroaromatic species involved in the process itself. Some indices, such as charge density, frontier electron density, polarizability, or free valence, pertain to electronic properties of the unperturbed neutral substrate, which is considered in an isolated state. Other indices, such as the localization energy, are related to the stability of the transitional or intermediate state of the substitution process, e.g., the n or a complex in electrophilic substitution reactions (Fig. 1). 

Bhanushali et al. [22] showed differences between porous UF polymer membranes and dense reverse osmosis/NF membranes. According to these authors, permeability can be correlated with the inverse of the solvent viscosity for UF membranes whatever the nature of the solvent. For reverse osmosis/NF membranes, a permeation model is proposed in which the flux relates to a solvent permeability coefficient, accounting for a number of solvent intrinsic parameters, like molar volume V , the viscosity p, the sorption value O, and to an intrinsic parameter of the membrane (the solid-vapor surface tension ysv). 

Rate and thermodynamic data are presented in Table 1. Correlation of the data with the Marcus theory has enabled estimates to be made for the reduction potentials and the intrinsic parameters of the cation radicals which are formed in the rate-limiting reaction. A similar procedure has been adopted in an analysis of the outer-sphere oxidation of ascorbic acid by a series of one-electron acceptor metal complexes. In this case, however, reactions of both HgA and HA are... 

The method was applied to the system Pi LaCl3. The authors identified new contributions to rank-6 crystal field one-electron cfp originating from the correlated mechanisms Bl k, k2). They stated that neither covalency nor ligand polarization could significantly contribute to the reduction of Slater parameters in crystals and identified probable influential excitations namely 4f —> nf. The quality of the final match between experimental and calculated intrinsic parameters is moderate 180/607, 38.8/30.3 and 15.8/9.12cm for A, and A, respectively, in Pr LaCl3. The paper is rather a theoretical reference to be consulted as to which process contributes most to the cjp and which one is therefore worth calculating. 

The ease of data fitting is conditioned by the knowledge we have initially about the common input parameters. We shall explain how we began this study in a complete unknown. The idea is to make a first rough fitting and to proceed subsequently by refinements. Obviously, after having determined the intrinsic parameters on several correlations, it will be easier and faster to simulate other tests. 

For further correlations of other tests, we should not modify the intrinsic and work only with the test dependent parameters. If a better correlation is obtained by changing an intrinsic parameter, we have to find an explanation of this, and examine the effect of this potential change on the previous simulations. 

These tools, implemented at each new test correlation, made it possible us to obtain quickly good numerical responses as presented hereafter, to describe the major phenomenological behaviours and to improve the data set, with common intrinsic parameters or with identified differences. 

Intrinsic viscosity measurements revealed a conformational transition upon heating from 26 to 40 °C, while the UV absorbance of the solution was insensitive to the change. The entropy parameters for PA were also discussed in light of the Flory-Krigbaum correlation between the second virial coefficient and theta temper-... 

A wide range of nitroxidcs and derived alkoxyamincs has now been explored for application in NMP. Experimental work and theoretical studies have been carried out to establish structure-property correlations and provide further understanding of the kinetics and mechanism. Important parameters are the value of the activation-deactivation equilibrium constant K and the values of kaa and (Scheme 9.17), the combination disproportionation ratio for the reaction of the nilroxide with Ihe propagating radical (Section 9.3.6.3) and the intrinsic stability of the nitroxide and the alkoxyamine under the polymerization conditions (Section 9.3.6.4). The values of K, k3Cl and ktieact are influenced by several factors.11-1 "7-"9 ... 

There are other sources of nonlinearity in the system, such as the intrinsic anharmonicity of the molecular interactions present also in the corresponding crystals. While these issues are of potential importance to other problems, such as the Griineisen parameter, expression (B.l) only considers the lowest order harmonic interactions and thus does not account for this nonlinear effect. We must note that if this nonlinearity is significant, it could contribute to the nonuniversality of the plateau, in addition to the variation in Tg/(do ratio. It would thus be helpful to conduct an experiment comparing the thermal expansion of different glasses and see whether there is any correlation with the plateau s location. 

Catalytic activity of solid acids in hydrocarbon conversions is often correlated with their acidity. Problems arise from the difficulty to bridge the gap between the equilibrium thermodynamic concept of acidity and the composite kinetic concept of catalytic activity [1], The correlation is meaningful if connected parameters are related to each other, namely, intrinsic activities are correlated with intrinsic acidities or relationship is established between corresponding apparent parameters. 

This approach yields spectral densities. Although it does not require assumptions about the correlation function and therefore is not subjected to the limitations intrinsic to the model-free approach, obtaining information about protein dynamics by this method is no more straightforward, because it involves a similar problem of the physical (protein-relevant) interpretation of the information encoded in the form of SD, and is complicated by the lack of separation of overall and local motions. To characterize protein dynamics in terms of more palpable parameters, the spectral densities will then have to be analyzed in terms of model-free parameters or specific motional models derived e.g. from molecular dynamics simulations. The SD method can be extremely helpful in situations when no assumption about correlation function of the overall motion can be made (e.g. protein interaction and association, anisotropic overall motion, etc. see e.g. Ref. [39] or, for the determination of the 15N CSA tensor from relaxation data, Ref. [27]). 

Correlation with Methyl Cation Affinity. Intrinsic barrier data for some of the other systems we have examined are shown in Table II and Figure 4. Note that the barriers vary widely with structure. Some insight into the mechanism of this variation is obtained by noting that the only thermodynamic parameter which correlates well with the purely kinetic intrinsic barriers is the methyl cation affinity (MCA) of the nucleophile... 

The major reasons for using intrinsic fluorescence and phosphorescence to study conformation are that these spectroscopies are extremely sensitive, they provide many specific parameters to correlate with physical structure, and they cover a wide time range, from picoseconds to seconds, which allows the study of a variety of different processes. The time scale of tyrosine fluorescence extends from picoseconds to a few nanoseconds, which is a good time window to obtain information about rotational diffusion, intermolecular association reactions, and conformational relaxation in the presence and absence of cofactors and substrates. Moreover, the time dependence of the fluorescence intensity and anisotropy decay can be used to test predictions from molecular dynamics.(167) In using tyrosine to study the dynamics of protein structure, it is particularly important that we begin to understand the basis for the anisotropy decay of tyrosine in terms of the potential motions of the phenol ring.(221) For example, the frequency of flips about the C -C bond of tyrosine appears to cover a time range from milliseconds to nanoseconds.(222)... 

Logarithmic bioconcentration factors have been shown to be correlated with the logarithmic octa-nol/water partition coefficient in aquatic organisms (Davies and Dobbs, 1984 de Wolf et al., 1992 Isnard and Lambert, 1988) and fish (Davies and Dobbs, 1984 Kenaga, 1980 Isnard and Lambert, 1988 Neely et al., 1974 Ogata et al., 1984 Oliver and Niimi, 1985). In addition, bioconcentration factors are well correlated by a linear solvation energy relationship (coimnonly known as LSER) that includes the intrinsic solute molecular volume and solvatochromic parameters that measnre hydrogen bond acceptor basicity and donor acidity of the componnd (Park and Cho, 1993). 

---