furnace parts not also evaporate under oxidizing conditions. One will need to develop new experimental approaches in order to carry out evaporation experiments under a range of conditions that may have prevailed in the early solar nebula. A promising new approach for this involves the evaporation of molten beads in a laser heated aerodynamic levitation furnace. In such an apparatus a molten sample is floated on top of a stream of a prescribed gas composition and heated to high temperature by a laser. Winpenny et al. (2019) have shown that materials evaporated in such a furnace do become isotopically fractionated. The levitation experiments have their own limitation in that the gas flow cannot be varied at will because of the flow needed to levitate a sample of a given size. However they do provide quantitative information on evaporation into a flowing gas, which is the sort of evaporation that could take place in impact plumes. Fedkin et al. (2015) have argued that the chemical compositions of at least some types of chondrule are best explained as having once been molten droplets in impact plumes
The present report limited itself to kinetic isotope effects in high‐temperature silicate systems. The interested reader will find a discussion of a large number of works reporting kinetic isotope fractionations in aqueous solutions in Watkins et al. (2017).
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