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The statistical theory

Quantitative evaluation of the stress-strain characteristics of the rubber network then involves calculation of the configurational entropy of the whole assembly of chains as a function of the state of strain. This calculation is considered in two stages calculation of the entropy of a single chain and calculation of the change in entropy of a network of chains as a function of strain. [Pg.35]


Wardlaw D M and Marcus R A 1987 On the statistical theory of unimolecular processes Adv. Chem. Rhys. 70 231-63... [Pg.1039]

Strong support for the statistical theory has been provided by computational dynamic fragmentation experiments (Holian and Grady, 1988). In... [Pg.304]

An idea of the present eomplexity of the statistical theory of rubberlike elastieity ean be garnered from Chapter 7 of a recent book on The Physics of Polymers, by Strobl (1996). [Pg.325]

Determine and document the statistical theory or national standards used. [Pg.551]

This present chapter will not focus on the statistical theory of overlapping peaks and the deconvolution of complex mixtures, as this is treated in more detail in Chapter 1. It is worth remembering, however, that of all the separation techniques, it is gas chromatography which is generally applied to the analysis of the most complex mixtures that are encountered. Individual columns in gas chromatography can, of course, have extremely high individual peak capacities, for example, over 1000 with a 10 theoretical plates column (3), but even when columns such as these are... [Pg.46]

Extension of the Statistical Theory of Resonating Valence Bonds... [Pg.343]

We may apply the statistical theory to determine the number of outer electrons involved in bond formation by determining... [Pg.404]

Extension of the statistical theory of resonating valence bonds to hyperelectronic metals... [Pg.407]

It is also possible to estimate the cross-link density from the stress-strain data, using the statistical theory of rubber-like elasticity [47,58]. For a swollen rubber the relationship is... [Pg.270]

From the statistical theory by Flory, the weight fraction of sol is given by ... [Pg.249]

Kolmogoroff A (1958) Collected works on the statistical theory of turbulence. Akademic Verlag, Berlin... [Pg.80]

The preceding equations will, of course, be somewhat in error owing to the neglect of intramolecular condensations. Very large species will be suppressed relatively more on this account. All conceivable errors can do no more, however, than to effect a distortion of the quantitative features of the predictions, which will be small in comparison with the vast difference between the branched polymer distribution and that usually prevailing in linear polymers. From this point of view, the statistical theory given offers a useful description of the state of affairs. [Pg.368]

This is Mooney s equation for the stored elastic energy per unit volume. The constant Ci corresponds to the kTvel V of the statistical theory i.e., the first term in Eq. (49) is of the same form as the theoretical elastic free energy per unit volume AF =—TAiS/F where AaS is given by Eq. (41) with axayaz l. The second term in Eq. (49) contains the parameter whose significance from the point of view of the structure of the elastic body remains unknown at present. For simple extension, ax = a, ay — az—X/a, and the retractive force r per unit initial cross section, given by dW/da, is... [Pg.474]

Before concluding this section, it must be pointed out that there are other fields of application of the SRH formalism. Thus, Karwowski et al. have used it in the study of the statistical theory of spectra [30,38]. Also, the techniques used in developing the p-SRH algorithms have proven to be very useful in other areas such as the nuclear shell theory [39,40]. [Pg.66]

These are most important realizations that will guide the evolution of multiple dimension chromatographic systems and detectors for years to come. The exact quantitative nature of specific predictions is difficult because the implementation details of dimensions higher than 2DLC are largely unknown and may introduce chemical and physical constraints. Liu and Davis (2006) have recently extended the statistical overlap theory in two dimensions to highly saturated separations where more severe overlap is found. This paper also lists most of the papers that have been written on the statistical theory of multidimensional separations. [Pg.22]

The concept of affine deformation is central to the theory of rubber elasticity. The foundations of the statistical theory of rubber elasticity were laid down by Kuhn (JJ, by Guth and James (2) and by Flory and Rehner (3), who introduced the notion of affine deformation namely, that the values of the cartesian components of the end-to-end chain vectors in a network vary according to the same strain tensor which characterizes the macroscopic bulk deformation. To account for apparent deviations from affine deformation, refinements have been proposed by Flory (4) and by Ronca and Allegra (5) which take into account effects such as chain-junction entanglements. [Pg.279]

To explain the difference between the experimental results and theory, Doherty et al. (4J have given an empirical and a theoretical hypothesis. The theoretical hypothesis concerns the question of the meaning to be attached to the concept of the "equivalent random link" in the statistical theory of the randomly-jointed chain. According to Doherty et al., the assumption that the optical properties of the chain are describable by a randomly jointed model, using the same value of n, as for the description of stress has no strictly logical foundation. [Pg.470]

Lifshitz IM (1968) Some problems of the statistical theory of biopolymers. Zh Eksp Teor Fiz 55 2408 [(1969) J Exp Theor Phys 28 1280], See also Lifshitz IM (1994) In Selected scientific works. Electronic theory of metals. Polymers and biopolymers. Nauka publishers, Moscow, p 212... [Pg.218]

M. L. Mehta, Random Matrices and the Statistical Theory of Energy Levels, Academic Press, New York, 1967. [Pg.740]

The earlier models (2-5) dealt primarily with the conformation of a single molecule at an interface and apply at very low adsorption densities. More recent treatments (6-10) take into account polymer-polymer and polymer-solvent interactions and have led to the emergence of a fairly consistent picture of the adsorption process. For details of the statistical theories of polymer adsorption, the reader is referred to publications by Lipatov (11), Tadros (12) and Fleer and Scheutjens (13). [Pg.29]

It is of considerable interest to compare the present model with the predictions of the statistical theories. In particular, the results will be compared with the theories of Scheutjens and Fleer (9,10,13). These authors have pointed out that their results are in general agreement with other published models. Comparison of the adsorption isotherms shown in Figure 1 with those given by Scheutjens and Fleer (see, for example, Figure 5 of Reference 13) shows excellent qualitative agreement. In each case, the isotherms consist of three regions as described above. [Pg.29]

Figure 2. Comparison of adsorption isotherms based on the present model (solid lines) with the statistical theory of Scheutjens and Fleer (symbols). The following values of the parameters were used... Figure 2. Comparison of adsorption isotherms based on the present model (solid lines) with the statistical theory of Scheutjens and Fleer (symbols). The following values of the parameters were used...
This book has only limited scope for describing control charts and the statistical theory on which they are based. Some simple applications are briefly described below, together with a simplified statistical explanation. For more detailed information, you should refer to the relevant standards and guides [1-5]. [Pg.147]

The extension of the cell model to multicomponent systems of spherical molecules of similar size, carried out initially by Prigogine and Garikian1 in 1950 and subsequently continued by several authors,2-5 was an important step in the development of the statistical theory of mixtures. Not only could the excess free energy be calculated from this model in terms of molecular interactions, but also all other excess properties such as enthalpy, entropy, and volume could be calculated, a goal which had not been reached before by the theories of regular solutions developed by Hildebrand and Scott8 and Guggenheim.7... [Pg.117]

Chapter 2 reviews the statistical theory of turbulent flows. The emphasis, however, is on collecting in one place all of the necessary concepts and formulae needed in subsequent chapters. The discussion of these concepts is necessarily brief, and the reader is referred to Pope (2000) for further details. It is, nonetheless, essential that the reader become familiar with the basic scaling arguments and length/time scales needed to describe high-Reynolds-number turbulent flows. Likewise, the transport equations for important one-point statistics in inhomogeneous turbulent flows are derived in Chapter 2 for future reference. [Pg.15]

In the statistical theory of fluid mixing presented in Chapter 3, well macromixed corresponds to the condition that the scalar means () are independent of position, and well micromixed corresponds to the condition that the scalar variances are null. An equivalent definition can be developed from the residence time distribution discussed below. [Pg.26]

Table 13.1). In the solid P(CH4) > P(CD4) but the curves cross below the melting point and the vapor pressure IE for the liquids is inverse (Pd > Ph). For water and methane Tc > Tc, but for water Pc > Pc and for methane Pc < Pc- As always, the primes designate the lighter isotopomer. At LV coexistence pliq(D20) < Pliq(H20) at all temperatures (remember the p s are molar, not mass, densities). For methane pliq(CD4) < pLiq(CH4) only at high temperature. At lower temperatures Pliq(CH4) < pliq(CD4). The critical density of H20 is greater than D20, but for methane pc(CH4) < pc(CD4). Isotope effects are large in the hydrogen and helium systems and pLIQ/ < pLiQ and P > P across the liquid range. Pc < Pc and pc < pc for both pairs. Vapor pressure and molar volume IE s are discussed in the context of the statistical theory of isotope effects in condensed phases in Chapters 5 and 12, respectively. The CS treatment in this chapter offers an alternative description. Table 13.1). In the solid P(CH4) > P(CD4) but the curves cross below the melting point and the vapor pressure IE for the liquids is inverse (Pd > Ph). For water and methane Tc > Tc, but for water Pc > Pc and for methane Pc < Pc- As always, the primes designate the lighter isotopomer. At LV coexistence pliq(D20) < Pliq(H20) at all temperatures (remember the p s are molar, not mass, densities). For methane pliq(CD4) < pLiq(CH4) only at high temperature. At lower temperatures Pliq(CH4) < pliq(CD4). The critical density of H20 is greater than D20, but for methane pc(CH4) < pc(CD4). Isotope effects are large in the hydrogen and helium systems and pLIQ/ < pLiQ and P > P across the liquid range. Pc < Pc and pc < pc for both pairs. Vapor pressure and molar volume IE s are discussed in the context of the statistical theory of isotope effects in condensed phases in Chapters 5 and 12, respectively. The CS treatment in this chapter offers an alternative description.

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Statistical Theories and the Information-Theoretic Approach

The Statistical Theory of Rubber Elasticity

The statistical mechanical theory of rubber elasticity

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Theories statistical theory

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