Complex motion of precipitation bands

Istvan Lagzi; Peter Papai; Zoltan Racz

doi:10.1016/j.cplett.2006.11.051

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Complex motion of precipitation bands

Istvan Lagzi·Peter Papai·Zoltan Racz

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Abstract

Formation and dynamics of an Al(OH)_3 precipitation ring is studied by diffusing NaOH into a gel containing AlCl_3. Limited feeding of the outer electrolyte (NaOH) is found to yield an intricate ring-dynamics which involves stopping and reversal of the direction of motion of the precipitation ring, and evolution into stationary multi-ring structures. A model of the ring-dynamics is developed by combining a phase separation scenario for the precipitation with the redissolution (complex formation) of the precipitate in the excess of the outer electrolyte.

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Istvan Lagzi, Peter Papai, Zoltan Racz. 2006-12-01. Complex motion of precipitation bands. https://doi.org/10.1016/j.cplett.2006.11.051

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