Where does vitrification collide?

In materials science, vitrification is the formation of a glass: a liquid cooled fast enough that it becomes a rigid solid while keeping the disordered, non-crystalline arrangement of the liquid, rather than settling into a regular crystal lattice. Zachariasen's 1932 The atomic arrangement in glass proposed the random-network picture of the glassy state that still underlies how glasses are understood. The referent is a state of matter defined by frozen-in disorder, characterised by the glass-transition temperature and viscosity, and it is a different construct from the fusing of ancient stone forts or the ice-free freezing of a living cell, even though the second shares its physical mechanism.[1]

Unit

The glass-transition temperature at which a supercooled liquid becomes a rigid glass

Recovery means

Not applicable

Measured by

Located by the glass-transition temperature in calorimetry and by the sharp rise in viscosity on cooling

In archaeology, vitrification names the puzzling transformation seen in the 'vitrified forts' of Europe, prehistoric stone ramparts whose rock has been partly melted and fused into glass by fire intense enough to raise a long question of whether the burning was deliberate construction, destruction by enemies, or ritual. Youngblood and colleagues' 1978 Celtic vitrified forts: Implications of a chemical-petrological study of glasses and source rocks analysed the glasses and their parent rocks to work out the temperatures reached and how the walls came to melt. The referent is a fire-induced alteration of built stone in the archaeological record, studied by petrology and experiment, and it is a wholly different thing from the physics of glass or the freezing of cells.[2]

Unit

The degree and pattern of fusion of stone in a burnt rampart

Recovery means

Not applicable

Measured by

Studied by petrology and geochemistry of the glasses and by experimental firing to estimate temperatures reached

In cryobiology, vitrification is a method of cryopreservation in which cells, embryos, or eggs are loaded with cryoprotectants and cooled so rapidly that their water solidifies into a glass rather than forming the ice crystals that would tear the cell apart. Rall and Fahy's 1985 Ice-free cryopreservation of mouse embryos at −196 °C by vitrification showed that living embryos could survive being frozen this way, founding a technique now central to fertility medicine. The referent is a preservation outcome in which biological material is held in a glassy, ice-free state, judged by survival after warming, and although it relies on the same physics as glass formation it is a distinct construct from a material's glass transition or a burnt prehistoric fort.[3]

Unit

The cooling rate and cryoprotectant needed to solidify a cell into a glass without ice

Recovery means

Warming returns the material to the liquid state; success is judged by survival and function afterward

Measured by

Assessed by survival, viability, and function of cells and embryos after warming from the vitrified state