spontaneous nucleation

[spän′tā·nē·əs ‚nü·klē′ā·shən]

(meteorology)

The nucleation of a phase change of a substance without the benefit of any seeding nuclei within or otherwise in contact with that substance; examples of such systems are a pure vapor condensing to its pure liquid state, a pure liquid freezing to its pure solid state, and a pure solution crystallizing to yield pure solute crystals.

Mentioned in ?

Crystallization

References in periodicals archive ?

There are three classes of nucleation: (1) homogeneous nucleation or spontaneous nucleation; (2) self-nucleation; and (3) heterogeneous nucleation [9], Homogeneous nucleation occurs in pure polymers due to the influence of supercooling also known as undercooling, which is the difference between the melt temperature (Tm) and the onset crystallization temperature ([T.sub.0]) [10].

Nucleating agents for high-density polyethylene--a review

In many of the 452 trials, protein crystals grew much earlier, at lower levels of supersaturation, on the minerals than they did when they crystallized by spontaneous nucleation.

Minerals for growth: mineral surfaces turn out to be useful platforms for growing protein crystals

Interaction between the polymer and the surface of the nucleating agent is essential in reducing the interfa-cial free energy barrier for spontaneous nucleation and growth, increasing crystallization rate and inducing crystallization at a lower degree of supercooling, i.e.

The effect of a sodium octacosanoate-based nucleating agent on the crystallization of thermoplastic polyurethanes

The uniformity of the shear-induced layer indicates spontaneous nucleation at the moment of shear, thereby eliciting synchronized growth.