The kinetics of microstructural evolution driven by phase coarsening (Ostwald ripening) in a binary, two-phase system were studied systematically at ultra high volume fractions the dispersed phase. Three-dimensional phase-field simulations and theoretical analysis are compared. Late-stage microstructure (VV>0.9) reported here. One interesting finding is that scaling exponents, m, for take value...

The reaction-diffusion master equation (RDME) is a model that allows for efficient on-lattice simulation of spatially resolved stochastic chemical kinetics. Compared to off-lattice hard-sphere simulations with Brownian dynamics or Green's function reaction dynamics, the RDME can be orders of magnitude faster if the lattice spacing can be chosen coarse enough. However, strongly diffusion-control...

Hot-injection synthesis is renowned for producing semiconductor nanocolloids with superb size dispersions. Burst nucleation and diffusion-controlled focusing during growth have been invoked to rationalize this characteristic yet experimental evidence supporting the pertinence of these concepts scant. By monitoring a CdSe in-situ X-ray scattering, we find that an extended event coincides 15–20% ...

Interdiffusion in multi-phase diffusion couples of polycrystalline Ti and polysynthetically twinned (PST) Ti-49.3 at.% Al, with the diffusion direction parallel to the lamellar planes, is investigated in the temperature range 973 – 1173 K. A reaction zone (RZ) of the α2-Ti3Al phase forms between the end materials and exhibits deeper penetration in the α2 lamellae than in the primary γ lamellae....

In this paper, carbon nanotubes (CNTs) were added into chitosan (CS) hydrogels in the form of chitosan modified CNTs (CS-CNTs) composites to prepare carbon nanotubes hydrogels (CNTs-GEL). The products, named CS-MWCNTs, were characterized by scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectroscopy. Swelling properties and effect of pH on controlled release performanc...

  Abstract : In this study, we prepared a LaNi0.3Al0.7O3 perovskite catalyst using a sol-gel related method (with prop ionic acid as a solvent) for use in the methane dry reforming reaction to produce synthesis gas. We defined the catalyst structure on the basis of X-ray diffraction analysis and measurements of the specific surface area and particle size distribution. The mixed oxide structure ...

The kinetics of Fe2O3→FeO reaction was investigated. The thermogravimetric (TGA) data covered the reduction of hematite both by pure species (nitrogen diluted CO or H2) and by their mixture. The conventional analysis has indicated that initially the reduction of hematite is a complex, surface controlled process, however once a thin layer of lower oxidation state iron oxides (magnetite, wüstite)...

Biological signals in cells are transmitted with the use of reaction cycles, such as the phosphorylation-dephosphorylation cycle, in which substrate is modified by antagonistic enzymes. An appreciable share of such reactions takes place in crowded environments of two-dimensional structures, such as plasma membrane or intracellular membranes, and is expected to be diffusion-controlled. In this w...

A degradation model for high-nickel positive electrode materials that undergo a structural reorganisation involving oxygen loss and the formation of disordered (spinel or rock-salt structure) passivation layer is presented first time. The thermally coupled continuum based on single-particle upon LiNi 0.8 Mn 0.1 Co O 2 (NMC811) layered oxide in this instance. theoretical framework assumes shrink...