Thermal processing annealing and evaporation

The time to crystallize - or thermally anneal - grains is strongly dependent on the temperature at Ta 630 K it will take 5 Myr (the lifetime of the disk), while at Ta 800 K the timescale becomes comparable to the orbital periods in the inner disks (5 yr), and at Ta 1200 K it takes just a few seconds. 

The process of condensation of minerals in the early solar nebula has long been invoked to explain the chemistry and mineralogy of primitive chondritic meteorites (e.g. Cameron 1963). Their observed bulk compositions show volatile-element depletions that are clearly smooth functions of calculated condensation temperature in a gas of solar composition (Davis 2006). Despite this success in explaining the bulk composition of chondrites, the diverse mineralogy of these bodies is not reproduced well in the condensation sequence calculations. To date, there is no incontrovertible evidence for direct condensation of rocky meteoritic material in the 

Thermal processing in protoplanetary nebulae Silicate emission features from six brown dwarf disks 

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