Nuclear, Plasma, and Radiological Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
J Phys Chem B. 2023 Jun 22;127(24):5422-5431. doi: 10.1021/acs.jpcb.3c01089. Epub 2023 Jun 9.
Antifreeze proteins (AFPs) bind to the ice-water surface and prevent ice growth at temperatures below 0 °C through a Gibbs-Thomson effect. Each adsorbed AFP creates a metastable depression on the surface that locally resists ice growth, until ice engulfs the AFP. We recently predicted the susceptibility to engulfment as a function of AFP size, distance between AFPs, and supercooling [ 2023, 158, 094501]. For an ensemble of AFPs adsorbed on the ice surface, the most isolated AFPs are the most susceptible, and when an isolated AFP gets engulfed, its former neighbors become more isolated and more susceptible to engulfment. Thus, an initial engulfment event can trigger an avalanche of subsequent engulfment events, leading to a sudden surge of unrestrained ice growth. This work develops a model to predict the supercooling at which the first engulfment event will occur for an ensemble of randomly distributed AFP pinning sites on an ice surface. Specifically, we formulate an inhomogeneous survival probability that accounts for the AFP coverage, the distribution of AFP neighbor distances, the resulting ensemble of engulfment rates, the ice surface area, and the cooling rate. We use the model to predict thermal hysteresis trends and compare with experimental data.
抗冻蛋白（AFP）通过吉布斯-汤姆逊效应与冰-水表面结合，防止在 0°C 以下温度下的冰生长。每个吸附的 AFP 在表面上创建一个亚稳凹陷，局部抵抗冰生长，直到冰吞没 AFP。我们最近预测了 AFP 大小、AFP 之间的距离和过冷度对吞没的易感性[2023,158,094501]。对于吸附在冰表面上的 AFP 集合，最孤立的 AFP 最容易被吞没，当一个孤立的 AFP 被吞没时，它以前的邻居变得更加孤立，更容易被吞没。因此，最初的吞没事件可以引发后续吞没事件的雪崩，导致不受控制的冰生长突然激增。这项工作开发了一个模型，用于预测在冰表面上随机分布的 AFP 钉扎点集合中，第一个吞没事件将发生的过冷度。具体来说，我们制定了一个不均匀的生存概率，该概率考虑了 AFP 覆盖率、AFP 邻近距离分布、由此产生的吞没速率集合、冰表面积和冷却速率。我们使用该模型预测热滞回线趋势，并与实验数据进行比较。
