The three-dimensional evolution of nanoligaments of nanoporous gold created by Ag–Au dealloying was studied during isothermal coarsening by X-ray nanotomography and microbeam Laue diffraction. The surface normal orientation, curvature and size of the gold nanoligaments were measured as a function of coarsening time (from 2 to 320 min). The following observations were made at 550, 600 and 650 C....

In this paper, an efficient and easy-to-implement coarsening algorithm is proposed for adaptive grids obtained using the newest vertex bisection method in two dimemsions. The new coarsening algorithm does not require storing the binary refinement tree explicitly. Instead, the structure is implicitly contained in a special ordering of triangular elements. Numerical experiments demonstrate that t...

We characterize the spatial spreading of the coarsening process in the Allen-Cahn equation in terms of the propagation of a nonlinear modulated front. Unstable periodic patterns of the Allen-Cahn equation are invaded by a front, propagating in an oscillatory fashion, and leaving behind the homogeneous, stable equilibrium. During one cycle of the oscillatory propagation, two layers of the period...

quantum dots of cds with hexagonal phase were prepared at relatively low temperature (60 oc) and short time by micro-emulsion (o/w) under ultrasound. this study was focused on the particle size distribution and the growth kinetics. the particle size distribution obtained from the optical absorption edge. it was relatively symmetrical with sonication time. in addition, an agreement was observed ...

ABSTRACT. We study two–dimensional coarsening by simulations for the Cahn–Hilliard model. A scale invariance of the sharp interface limit of this model suggests that the characteristic length scale grows proportional to , respectively the energy density decreases as . We compare the coarsening dynamics for different choices of data for different volume fractions. We observe that, depending on t...

An exponent β which characterises non-equilibrium coarsening processes is calculated in a deterministic solvable model of coarsening for a 1D q-state Potts system. We study how the fraction of sites P which have never changed their state, scale with the characteristic domain length 〈l〉. β is defined by P ∼ 〈l〉β−1. We propose a new model of coarsening that prevents correlations from developing b...

Isotropic magnetic field modulations cause the formation and coarsening of transient two dimensional paramagnetic colloidal networks. We show that the virgin transient network consists of sub- and supercritical meshes. In the initial coarsening process subcritical meshes shrink while supercritical meshes grow. While the coarsening is a truly non-equilibrium process, the critical nucleation size...

An exponent β which characterises non-equilibrium coarsening processes is calculated in a deterministic solvable model of coarsening for a 1D q-state Potts system. We study how the fraction of sites P which have never changed their state, scale with the characteristic domain length 〈l〉. β is defined by P ∼ 〈l〉β−1. We propose a new model of coarsening that prevents correlations from developing b...