标题： 简单剪切对打结聚合物线团和球状体的影响 显示英文标题

标题： Effect of simple shear on knotted polymer coils and globules

摘要： 我们通过广泛的分子动力学（MD）模拟研究了库埃特流对结状线性聚合物链的影响。 通过多粒子碰撞动力学（MPCD）方法考虑了水动力相互作用。 聚合物链最初包含一个静止的简单三叶草结，以一种粗粒度的珠子-弹簧模型描述，处于卷曲或球状状态。 我们证明，在剪切作用下，聚合物线圈中存在的松散局部化结通常会收紧到超过一定剪切速率阈值的几个片段。 在大剪切速率下，聚合物会发生类似翻滚的运动，在此过程中结的大小会发生波动。 相反，受剪切的结状球体会展开成一种复杂的珍珠项链结构，由次级球体组成并回折到自身，其中结的类型会随时间变化。 显示英文摘要

摘要： We explore the effect of Couette flow on knotted linear polymer chains with extensive Molecular Dynamics (MD) simulations. Hydrodynamic interactions are accounted for by means of Multi-Particle Collision Dynamics (MPCD). The polymer chain, containing originally a simple trefoil knot at rest, is described by a coarse-grained bead-spring model in a coil or globular state. We demonstrate that under shear existing loosely localized knots in polymer coils typically tighten to several segments beyond a certain shear rate threshold. At large shear rates the polymer undergoes a tumbling-like motion during which knot sizes can fluctuate. In contrast, sheared knotted globules unwind into a convoluted pearl-necklace structure of sub-globules that folds back onto itself and in which knot types change over time.