Surface Structure and Catalytic COCO Oxidation Oscillations

A cellular automaton model is used to describe the dynamics of the catalytic oxidation of $CO$ on a $Pt(100)$ surface. The cellular automaton rules account for the structural phase transformations of the $Pt$ substrate, the reaction kinetics of the adsorbed phase and diffusion of adsorbed species. The model is used to explore the spatial structure that underlies the global oscillations observed in some parameter regimes. The spatiotemporal dynamics varies significantly within the oscillatory regime and depends on the harmonic or relaxational character of the global oscillations. Diffusion of adsorbed $CO$ plays an important role in the synchronization of the patterns on the substrate and this effect is also studied.Comment: Latex file with six postscript figures. To appear in Physica

Urzadzenie laboratoryjne do statycznego zageszczania gleby

Opis laboratoryjnego stanowiska badawczego do ugniatania gleby rolniczej naciskami jednostkowymi w zakresie od 15 do 300 kPa, wywieranymi za pomocą stempla na glebę umieszczony w cylindrach.The paper describes laboratory stand, designed for experimental compacting the agricultural soils. Available specific pressures inserted on the soil placed in cylinder by a stamp, fall within the range from 15 to 300 kPa. Equations used for scaling the device and computation of measurement error are also included

Transient evolution towards a unique stable state: Stochastic analysis of explosive behavior in a chemical system

A stochastic description of an isothermal chemical system showing explosive behavior is developed. Numerical analysis shows the appearance of multiple humps of the probability distribution. This implies the onset of chaotic behavior reflecting the random character of the ignition process. Various characteristics of the phenomenon, such as onset time and duration, are studied in terms of the size of the system, the intrinsic parameters, and initial conditions. The implications of the results in combustion are discussed. © 1983 Plenum Publishing Corporation.SCOPUS: ar.jinfo:eu-repo/semantics/publishe