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Mesoscopic transformation

In similar concept, the particle-mediated crystallization theory was used to explain well the formation of solid-phase nucleation in the reaction system. This theory suggested that some mesoscopic transformation process takes place in the solid phase followed by multiple nucleation growth phenomena. At the initial phase, it reorganizes into mesoscopic crystals followed by an orderly beautifully mesostructure via self-assembly, of well-aligned size and shape. The crystallographic orientation of the particle is equal in all directions so that the mesoscopic crystals can be reorganized in such a way under the processes of self-assembly. On the basis of the above explanation. Scheme 3.1 represents nucleation mechanism. [Pg.70]

Mesoscopic Transformation and Controlled Higher Order Self-Assembly of Nanoparticles... [Pg.50]

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]

This interpretation of the master equation means that is has an entirely different role than the Chapman-Kolmogorov equation. The latter is a nonlinear equation, which results from the Markov character, but contains no specific information about any particular Markov process. In the master equation, however, one considers the transformation probabilities as given by the specific system, and then has a linear equation for the probabilities which determine the (mesoscopic) state of that system. [Pg.98]

In the case of the water-soluble metallo-host possessing a benzene side-walled, the cavities were observed to self-associate in water to form well-defined dimers which further self-assemble, although solutions in water remained clear up to relatively high concentrations (> 30 mM). Samples of these solutions were studied with TEM and revealed rather ill defined, scroll-like mesoscopic assemblies with lengths up to 10 pm, and a typical width of approximately 100 nm. Enlargement of the receptor side-walls with naphthalene moieties, increases both the hydrophobic character of the hosts and the 7t-7t interactions between the molecules. When the concentration of this naphthalene compound in water was increased to approximately 2 mM, the solution transformed into a turbid dispersion, which remained for days without any precipitation. [Pg.152]

Based on the experiences with PMO precursors of varying polarity, M. Cornelius hypothesized in his Ph.D. thesis that precursors with a log K(,w value larger than 6.7 (in their ethoxy form) do not allow an easy transformation to a mesoscopically ordered organosilica, at least not with standard procedures (i.e., without the addition of further structure-forming agents or by addition of cosolvents).72... [Pg.52]

Model electrodes with a dehned mesoscopic structure can be generated by a variety of means, e.g., electrodeposition, adsorption from colloidal solutions, and vapor deposition and on a variety of substrates. Such electrodes have relatively well-dehned physico-chemical properties that differ signihcantly from those of the bulk phase. The present work analyzes the application of in-situ STM (scanning tunneling microscopy) and ETIR (Eourier Transformed infrared) spectroscopy in determining the mesoscopic structural properties of these electrodes and the potential effect of these properties on the reactivity of the fuel cell model catalysts. Special attention is paid to the structure and catalytic behavior of supported metal clusters, which are seen as model systems for technical electrocatalysts. [Pg.551]

At the macroscopic scale, shear localization flow in the alloy develops during initial increments of deformation. Softening and globularization of structure in the macro shear band lead to realization of deformation at mesoscopic scale. In this case the mesoscopic scale deformation is determined by cooperative grain boundary sliding leading to superplastic flow. Superplastic flow results in deformation accumulation in the central area of the sample and impedes in structure transformation in periphery regions. [Pg.407]

The underlying physical model, reflecting the transformation from an individual mesoscopic cluster or particle, through the interacting particle regime to the thin film, has been investigated. [Pg.1478]

After a significant amount of hydrolysis and condensation has taken place, a three-dimensional network of metal and oxygen forms within the sol (metal-oxygen colloids suspended in a liquid) and the viscosity of the sol increases. As condensation continues, the sol transforms into a nonfluid gel and an interconnected and fairly rigid 3-D network extends throughout the entire sample container. The resulting wet gel is an amorphous, porous metal oxide with water and alcohol in its mesoscopic pores. Typically, the solid phase is between 5 and 10% of the total volume. [Pg.188]

The expression [P/(s + is the Laplace transform of the density of the Gamma process [15]. Therefore, we can find an explicit expression for the mesoscopic density of particles for x > 0 ... [Pg.78]

LBM was originally proposed by McNamara and Zanetti [3] to circumvent the limitations of statistical noise that plagued lattice gas automata (EGA). LBM is a simplified kinetic (mesoscopic) and discretized approximation of the continuous Boltzmarui equation. LBM is mesoscopic in nature because the particles are not directly related to the number of molecules like in DSMC or MD but representative of a collection of molecules. Hence, the computational cost is less demanding compared with DSMC and MD. Typical LBM consists of the lattice Boltzmann equation (LBE), lattice stmcture, transformation of lattice units to physical units, and boundary conditions. [Pg.2414]


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