Scattering-mediated photothermal heating in plasmonic PES/Au membranes for heterogeneous catalysis

Scattering-mediated photothermal process in the PES/Au membranes enabled local temperature heating inside the composite membrane to accelerate the kinetics of a model chemical reaction.

Numerical Investigations on the Nanosecond Pulse Discharge Process of Disk-Shape Plasma Igniter

Based on nonequilibrium plasma dynamics of air discharge, the dynamic model of two-dimensional plasma is established by combining the plasma dynamic model, chemical reaction equations and Navier-Stokes equations. The discharge process of disk-shape plasma igniter is simulated. The process of discharge stream formation is obtained, which results from by electrons’ movement and aggregation. At

Analysis of chemical kinetic systems over the entire parameter space IV. The Sal’nikov oscillator with two temperature-dependent reaction rates

This paper investigates a model chemical reaction in which a substance undergoes a two-stage decay, each stage exhibiting Arrhenius temperature dependence. The system is assumed to be well stirred so it is described by two highly nonlinear ordinary differential equations containing four parameters. Degenerate bifurcation theory and numerical analysis are used to investigate the behaviour of the system over the whole of physical parameter space. A large number of degenerate bifurcations are identified and located and the system is shown to exhibit 16 qualitatively different phase portraits. Degeneracies of higher codimension than would be expected occur in this system giving rise to some highly non-uniform behaviour both in phase and parameter space. This behaviour seems to be generic in thermokinetic systems with more than one Arrhenius nonlinearity.

Limit-cycle behaviour in a model chemical reaction: the Sal’nikov thermokinetic oscillator

The Sal’nikov thermokinetic oscillator is a model chemical reaction consisting of a two-stage decay of some chemical species. The first stage is a straightforward first-order decay process at constant temperature, but the second stage is exothermic, and is assumed to be governed by Arrhenius kinetics. When the containing vessel is well-stirred, the kinetic rate equation for the reaction along with an equation expressing conservation of energy leads to a system of two ordinary differential equations describing the behaviour of the process. The equations are coupled and highly nonlinear, and their solution gives the temperature inside the vessel and the concentration of the intermediate chemical species. Under certain circumstances, sustained periodic oscillations in these two quantities are possible. In this paper, I give a rigorous proof that these remarkable oscillations are not possible for certain combinations of the defining physical parameters. A numerical solution technique for obtaining periodic oscillations in the system is then presented; the method gives results of great accuracy, it automatically determines the stability of the solution, and is capable of computing unstable periodic orbits. Results of extensive numerical investigation are presented, and the occurrence of unstable limit cycles and multiple solutions is discussed in detail.