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Dynamical scaling

These results are the same as for rigid spheres the characteristic behaviour of the dilute solution is quite similar to the suspension of spheres of radius Rg. [Pg.103]

Calculation of Dq based on the renormalization group theory is given by Oono et In the good solvent limit this result is written as [Pg.103]

It has been proposed that the static scaling law described in Section 2.6 can be generalized to dynamical phenomena. The hypothesis is that, for a polymer described by the Zimm model, when the parameters of the model are changed as [Pg.103]

The exponent v is the same as that which appeared in the static scaling (v is 1/2 in 9 solvent and about 3/S in a good solvent). [Pg.103]

Though experimental confirmation of dynamical scaling is not so satisfactory as static scaling, and there is a delicate theoretical problem [Pg.103]


A signature of the dynamical scaling is evidenced by the collapse of the experimental data to a scaled fonn, for a (i-dimensional system ... [Pg.734]

Considerable amount of research effort has been devoted, especially over the last tln-ee decades, on various issues in domain growth and dynamical scaling. See the reviews [13,14, H, 16 and 17],... [Pg.735]

M. Kardar, G. Parisi, Y. C. Zhang. Dynamic scaling of growing interfaces. Phys Rev Lett 56 889, 1986. [Pg.434]

The Rouse and Zimm models are valid only under 0-conditions. To extend their range of applicability into good solvent conditions, several improvements have been proposed to include excluded volume effects. Dynamical scaling, however, provides probably the simplest approach to the problem [30],... [Pg.93]

The dynamic scaling argument supposes that when the geometrical parameters of the chain (i.e. N and lp) are changed from N into N/A and lp into lpV, any physical quantity (A), either static or dynamic, related to the molecular size will be transformed into XXA. The parameter v is the exponent in Eq. (9) and is equal to 1/2 in 0-solvent and 3/5 in good solvent. [Pg.94]

Another approach, neglecting the details of the chemical structure and concentrating on the universal elements of chain relaxation, is based on dynamic scaling considerations [4, 11], In particular in polymer solutions, this approach offers an elegant tool to specify the general trends of polymer dynamics, although it suffers from the lack of a molecular interpretation. [Pg.3]

Special theoretical insight into the internal relaxation behavior of polymers can also be provided on the basis of dynamic scaling laws [4,5]. The predictions are, however, limited since only general functional relations without the corresponding numerical prefactors are obtained. [Pg.73]

If the crossover points Q (x) are determined from Fig. 45, taking the x-values at half-step height, Q (x) = 1/1 (x) = (0.7 + 0.2)x is obtained in the case of the PS system. This has to be compared with static value Qs (x) = 1.6x, derived from the same polymer solvent system by elastic neutron scattering [103], As long as no corresponding data from other polymer solvent systems are available, the final decision as to whether static and dynamic scaling lengths coincide or not, is still open. [Pg.87]

The scaling of the relaxation modulus G(t) with time (Eq. 1-1) at the LST was first detected experimentally [5-7]. Subsequently, dynamic scaling based on percolation theory used the relation between diffusion coefficient and longest relaxation time of a single cluster to calculate a relaxation time spectrum for the sum of all clusters [39], This resulted in the same scaling relation for G(t) with an exponent n following Eq. 1-14. [Pg.184]

The classical theory predicts values for the dynamic exponents of s = 0 and z = 3. Since s = 0, the viscosity diverges at most logarithmically at the gel point. Using Eq. 1-14, a relaxation exponent of n = 1 can be attributed to classical theory [34], Dynamic scaling based on percolation theory [34,40] does not yield unique results for the dynamic exponents as it does for the static exponents. Several models can be found that result in different values for n, s and z. These models use either Rouse and Zimm limits of hydrodynamic interactions or Electrical Network analogies. The following values were reported [34,39] (Rouse, no hydrodynamic interactions) n = 0.66, s = 1.35, and z = 2.7, (Zimm, hydrodynamic interactions accounted for) n = 1, s = 0, and z = 2.7, and (Electrical Network) n = 0.71, s = 0.75 and z = 1.94. [Pg.184]

In what follows we will discuss systems with internal surfaces, ordered surfaces, topological transformations, and dynamical scaling. In Section II we shall show specific examples of mesoscopic systems with special attention devoted to the surfaces in the system—that is, periodic surfaces in surfactant systems, periodic surfaces in diblock copolymers, bicontinuous disordered interfaces in spinodally decomposing blends, ordered charge density wave patterns in electron liquids, and dissipative structures in reaction-diffusion systems. In Section III we will present the detailed theory of morphological measures the Euler characteristic, the Gaussian and mean curvatures, and so on. In fact, Sections II and III can be read independently because Section II shows specific models while Section III is devoted to the numerical and analytical computations of the surface characteristics. In a sense, Section III is robust that is, the methods presented in Section III apply to a variety of systems, not only the systems shown as examples in Section II. Brief conclusions are presented in Section IV. [Pg.143]

Figure 34. At the early stages of the phase separation, the scaling of the curvature distributions is in accordance with the dynamic scaling hypothesis [Eqs. (4)—(7)] (the order parameter is nonconserved). Figure 34. At the early stages of the phase separation, the scaling of the curvature distributions is in accordance with the dynamic scaling hypothesis [Eqs. (4)—(7)] (the order parameter is nonconserved).
For the symmetric system (< )0 = 0.5) the scaling exponent for the Euler characteristic has been found in accordance with the dynamic scaling hypothesis x L(t) 3 (see Section I.G). The homogeneity index, HI, of the interface defined as [222]... [Pg.225]

The time dependence of the heterogeneons reaction over heterogeneous surface will be discussed with the help of dynamic scaling theoiy. [Pg.370]

Table 1. Scaling exponents in dynamic scaling theory for ER reactions over different rough surface with same surface density and different rough surface with different... Table 1. Scaling exponents in dynamic scaling theory for ER reactions over different rough surface with same surface density and different rough surface with different...
Schreier H, Brown S (2004) Multiscale approaches to water management land-use impacts on nutrient and sediment dynamics. Scales in Hydrology and Water Management, Intern. Assoc. Hydrol. Sci, lAHS Publ, 287 61-75... [Pg.272]

Parameters Obtained from Dynamic Scaling Analysis... [Pg.232]

In a full dynamics scaling analysis, the imaginary component of the dynamic susceptibility of a spin glass is scaled according to [130]... [Pg.233]


See other pages where Dynamical scaling is mentioned: [Pg.733]    [Pg.734]    [Pg.734]    [Pg.746]    [Pg.513]    [Pg.177]    [Pg.116]    [Pg.230]    [Pg.141]    [Pg.154]    [Pg.225]    [Pg.232]    [Pg.371]    [Pg.385]    [Pg.386]    [Pg.388]    [Pg.465]    [Pg.218]    [Pg.231]    [Pg.233]   
See also in sourсe #XX -- [ Pg.212 ]




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Dynamic scaling

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