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Phase transitions modelling

In the phase transition model (4) long wavelength modes are coupled to short wavelengths modes by nonlinear couplings (21). It is not known whether this model can be solved exactly except for numerical methods. [Pg.286]

Phase transition models, oscillatory reactions, 39 92-97 Phenanthrene... [Pg.174]

To rigorously test the phase transition model, one must demonstrate that surface lipids actually do melt at the critical temperature, and that melted lipids are in fact more permeable to water than solid ones. A variety of biophysical techniques have been applied to this problem (Table 6.1). These have included direct biophysical measurements of lipid properties, and associated measurements of water-loss. In general, these studies have supported... [Pg.104]

For a solid-state reaction, one of the solutions of Equation 3.1 is the Avrami-Erofeev equation [3], The phase transition model that derives this equation supposes that the germ nuclei of the new phase are distributed randomly within the solid following a nucleation event, grains grow throughout the old phase until the transformation is complete. Then, the Avrami-Erofeev equation is [3]... [Pg.105]

Fig. 6. General representations of heterogeneous oscillatory mechanisms, (a) Buffer-step model (b) coverage-dependent activation energy (c) empty-site model (d) Sales-TUrner-Maple model (e) Pt(lOO) phase transition model (f) Dagonnier model (g) blocking/ reactivation model (h) bulk-phase transition model. Fig. 6. General representations of heterogeneous oscillatory mechanisms, (a) Buffer-step model (b) coverage-dependent activation energy (c) empty-site model (d) Sales-TUrner-Maple model (e) Pt(lOO) phase transition model (f) Dagonnier model (g) blocking/ reactivation model (h) bulk-phase transition model.
Therefore, the following hypothetical mechanism has been developed in accordance with the dispersion/ flocculation phase transition model for conductive blends and in accordance with results published about impact modification. [Pg.626]

Figure 18.1 is a comparison of the simple M approximation and more refined phase-transition models. The mixing is assumed to be adiabatic and the release conditions correspond to the most humid case of the FLADIS ammonia field experiments (Nielsen et al., 1997 Nielsen and Ott, 1996). Wheatley s model (solid line) is the most accurate one since this includes the hygroscopic effect of ammonia. This solution may he divided into three domains dry mixing, nearly pure-water aerosols, and nearly pure ammonia aerosols. Experimentation with the model input reveals that atmospheric moisture affects the aerosol formation in two ways the relative humidity determines the limit of transition between the... [Pg.410]

Phase Transition Models Such models are often considered in the form... [Pg.152]

Employing the form (1.85) to phase transition modeled by Eq. (1.79) the absolute finite critical temperature is predicted with the form (Putz Ori, 2012)... [Pg.44]

This model, as wets discussed in Chap.6, gives one an opportunity to describe the kinetics of non-ideal gas media in static and fluctuating surface field. Therefore, when approximating the kinetic operators (6.2.4), (6.2.5) one can use the results of quasiparticle method for non-ideal media kinetics (Dubrovskiy and Bogdanov 1979b), theory of liquids (Croxton 1974), theory of Brownian motion (Akhiezer and Peletminskiy 1977), theory of phase transitions, models of equilibrium properties of such systems (Jaycock and Parfitt 1981) with further application of methods of statistical thermodynamics of irreversible processes (Kreuzer and Payne 1988b) and experimental data on pair correlation function (Flood 1967). [Pg.46]

Here we give an overview of fluctuation dominated thermotropic liquid crystal phase transitions with a few hints of emerging aspects. From this perspective, the situation may be fairly summarized by noting that while analogies to phase transition models in spin-space (e.g. XY model with two components for the order parameter or Ising model with one) or momentum space (superconductivity) are a powerful tool to predict qualitative behavior for fluctuation dominated, real space, high temperature liquid crystal phase transitions, there is a significant gap between several quantitative (and qualitative) expectations and experimental measurements. [Pg.413]

Variation dL/ dx with x for the first order phase transition model and the equilibrium soap film configurations within the four-pin model, with the illustration of the corresponding energies with respect the configurations a and b. (a) Pair of pins are close to each other (b) pairs of pins are widely separated. Note that the lines in reality are two-dimensional, but their sizes do not change in the other dimension. [Pg.86]

Temporal Restrictions. The focus is on the continuity phases in long term economic development. In the phase transition model of Kondratieff, Kuznets and Schumpeter these are the periods of recovery, boom and recession which lie inbetween major discontinuities such as depressions and clusters of basic innovations which tend to occur during depressions [5.14]. [Pg.143]


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First-order phase transition lattice models

Gaussian model, phase transitions

Landau model, phase transitions

Model transit

Modeling phase

Oscillatory reactions phase transition models

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Phase transition models, oscillatory

Phase transitions ammonium triiodate crystal model

Phase transitions, diffusion models

The Schlogl model of first-order phase transition

The Schlogl model of second-order phase transition

Transition model

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