title: Flow-driven pattern formation in the calcium-oxalate system.
abstract: The precipitation reaction of calcium oxalate is studied experimentally in the presence of spatial gradients by controlled flow of calcium into oxalate solution. The density difference between the reactants leads to strong convection in the form of a gravity current that drives the spatiotemporal pattern formation. The phase diagram of the system is constructed, the evolving precipitate patterns are analyzed and quantitatively characterized by their diameters and the average height of the gravity flow. The compact structures of calcium oxalate monohydrate produced at low flow rates are replaced by the thermodynamically unstable calcium oxalate dihydrate favored in the presence of a strong gravity current.
authors.affiliation: Department of Physical Chemistry and Materials Science, University of Szeged, Aradi vértanúk tere 1., Szeged H-6720, Hungary.
authors.forename: Bíborka
authors.initials: B
authors.lastname: Bohner
authors.affiliation: Department of Physical Chemistry and Materials Science, University of Szeged, Aradi vértanúk tere 1., Szeged H-6720, Hungary.
authors.forename: Balázs
authors.initials: B
authors.lastname: Endrődi
authors.affiliation: Department of Applied and Environmental Chemistry, Rerrich Béla tér 1., Szeged H-6720, Hungary.
authors.forename: Dezső
authors.initials: D
authors.lastname: Horváth
authors.affiliation: Department of Physical Chemistry and Materials Science, University of Szeged, Aradi vértanúk tere 1., Szeged H-6720, Hungary.
authors.forename: Ágota
authors.initials: Á
authors.lastname: Tóth