Strobes are pyrotechnic compositions which show an oscillatory combustion; a dark phase and a flash phase alternate periodically. The strobe effect has applications in various fields, most notably in the fireworks industry and in the military area. All strobe compositions mentioned in the literature were discovered by trial and error methods and the mechanisms involved remain unclear. Many oscillatory systems such as Belousov-Zhabotinsky reactions, cool flames, selfpropagating high-temperature synthesis have been observed and theories developed to elucidate their unstable behavior based on chemical interactions or based on physical processes. These systems are compared to experimental observations made on strobe mixtures. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Strobes: pyrotechnic compositions that show a curious oscillatory combustion.

Stroboskopgemische sind pyrotechnische Zusammensetzungen, die ein oszillierendes Verbrennungsverhalten zeigen; eine Dunkel- und eine Leuchtphase alternieren periodisch. Der Stroboskopeffekt wird in verschiedenen Bereichen, aber hauptsachlich in der Feuerwerksindustrie und im militarischen Bereich angewendet. Alle Stroboskopgemische, die in der Literatur beschrieben werden, wurden durch systematisches Ausprobieren entdeckt und die zugrundeliegenden Mechanismen bleiben ungeklart. Viele oszillierende Systeme wurden beobachtet, und es wurden Theorien entwickelt, die auf chemischen Prozessen oder physikalischen Prozessen beruhen, um ihr instabiles Verhalten aufzuklaren. Diese Systeme werden mit experimentellen Beobachtungen an Stroboskopgemischen verglichen.

Stroboskopgemische: pyrotechnische Mischungen mit oszillierendem Verbrennungsverhalten

A zinc anode in acidic media is a new oscillatory electrochemical system which manifests interesting behaviors, from steady states to simple oscillations and chaos. This paper presents an experimental study of the influence of metal ions on the shape, amplitude and duration of the cell potential oscillations, and gives a qualitative explanation of the system’s behavior. A small quantity of Cu2+, Zn2+ or Fe3+ ions added to the system change dramatically the potential oscillations from chaotic behavior to simple oscillations. The method may be used for chaos attenuation.

Influence of Metal Ions on Oscillatory Behavior of Zinc Anode in Nitric Acid-Potassium Dichromate Media

This paper presents current oscillations of a Zn anode in solutions of nitric acid and potassium dichromate. The effects of the nitric acid concentration were investigated. The system was analyzed using cyclic voltammetry, current-time plots and attractors. It was found that the concentration of nitric acid has a major effect on the behavior of the system and it is proposed that zinc hydroxide precipitation-dissolution processes are responsible for the current oscillations.

http://www.doiserbia.nb.rs/img/doi/0352-5139/2008/0352-51390802221C.pdf

Ervin Salló

Papers

Periodic current oscillations of zinc in nitric acid solutions