| Abstract
| - The generic heterogeneous effect of foreign particles on 3D nucleation was examined in terms of therelative size and the interfacial interaction and structural match with the crystallizing phase in terms ofa so-called interfacial correlation function f(m,x). At low supersaturation, nucleation is controlled by foreignbodies with a relatively small curvature and/or an optimal interfacial interaction and structural matchwith the crystallizing phase. This is characterized by a small interfacial correlation function f(m,x) (f(m,x)→ 0). At high supersaturation, nucleation on foreign particles having a weak interaction and poor structuralmatch with the nucleating phase (f(m,x) → 1) will govern the kinetics. It follows that if a wide range ofsupersaturations are applied in a crystallization system, a sequence of progressive heterogeneous nucleationprocesses, characterized by different interfacial correlation function f(m,x)s, can be identified, where genuinehomogeneous nucleation can be regarded as the up-limit of heterogeneous nucleation. To check the aboveresults, experiments on the nucleation of organic crystals and CaCO3 from aqueous solutions were carriedout under gravity and microgravity. The results are in excellent agreement with our prediction.
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