Discontinuities in Supercooled Ionic Melts

Equiaxed dendritic solidification in supercooled melts

The growth of equiaxed dendrites from a pure supercooled melt is examined. We propose modifications to the classical Ivantsov theory that allow for consideration of multiple interacting dendrites. The modified theory reveals the existence of a steady-state dendritic solidification mode in a frame of reference moving with the dendrite tip. This regime should be valid from the onset of nucleation...

Nucleation Studies on Ionic Melts

INTRODUCTION Previous work on crystal nucleation in one-component melts has largely been confined to molecular liquids or metals. Molecular liquids have been studied in bulk", and in the form of clouds of droplets produced by condensation in supersaturated vapourv". Metals have also been studied in bulk 7, 8, and as droplets of microscopic size. These were produced either singly by melting smal...

Stringlike correlated motion in the dynamics of supercooled polymer melts

Stress distribution and the fragility of supercooled melts.

We formulate a minimal ansatz for local stress distribution in a solid that includes the possibility of strongly anharmonic short-length motions. We discover a broken-symmetry metastable phase that exhibits an aperiodic, frozen-in stress distribution. This aperiodic metastable phase is characterized by many distinct, nearly degenerate configurations. The activated transitions between the config...

Ionic Strength and Protonic Activity of Supercooled Solutions

Aqueous-organic mixtures can be used to lower freezing points in the study of some enzymic reactions at subzero temperatures. It is necessary to work at suitable ionic strengths and protonic activities and to know how these parameters vary with temperature. This paper deals with the provision of a controlled ionic environment and indicates how to obtain a desired ionic content in order to study...