The Chemical Langevin Equation (CLE), which is a stochastic differential equation driven by a multidimensional Wiener process, acts as a bridge between the discrete stochastic simulation algorithm and the deterministic reaction rate equation when simulating (bio)chemical kinetics. The CLE model is valid in the regime where molecular populations are abundant enough to assume their concentrations...

the kinetic of the heterogeneous chemical reaction of aluminum hydroxide and fluosilicic acid was studied. it was found that the diffusion of the reactants through the porous silica coating to the aluminum hydroxide surface and the interfacial chemical reaction between the diffusing reactant and aluminum hydroxide platelets control the overall reaction rate. these two phenomena were studied and...

The time responses of two electrochemical methods, amperometry (AMP) and cyclic voltammetry (CV), used in a microchannel to detect the concentration variations of an outer-sphere redox species were compared. Overall, our results show that the temporal resolution of AMP is superior to the one of CV. As no secondary reaction (formation of chemical bounds, adsorption, etc.) can hinder the detectio...

The pulsed electrical excitation of reactive metals like aluminum in water triggers a fast and highly energetic chemical reaction generating gaseous products. For applications such as fuses, safe explosives or fast gas generation, it is desirable to maximize the ratio of conductor mass to stored electrical energy while rapidly attaining a high resistive state. Various techniques have been used ...

Reaction zones formed at 790 °C between solid titanium and liquid Ag-Cu eutectic alloys (pure and Ti-saturated) have been characterized. When pure Ag-Cu eutectic alloy with 40 at.% Cu is used, the interface reaction layer sequence is: αTi / Ti2Cu / TiCu / Ti3Cu4 / TiCu4 / L. Because of the fast dissolution rate of Ti in the alloy, the reaction zone remains very thin (3-6 μm) whatever the reacti...

If for a chemical reaction with a known reaction mechanism the concentration profiles are accessible only for certain species, e.g. only for the main product, then often the reaction rate constants cannot uniquely be determined from the concentration data. This is a well-known fact which includes the so-called slow-fast ambiguity. This work combines the question of unique or non-unique reaction...

PDE-constrained optimization problems, and the development of preconditioned iterative methods for the efficient solution of the arising matrix system, is a field of numerical analysis that has recently been attracting much attention. In this paper, we analyze and develop preconditioners for matrix systems that arise from the optimal control of reaction-diffusion equations, which themselves res...