标题： 活性聚合物链的局部调谐流体动力学 显示英文标题

标题： Locally tuned hydrodynamics of active polymer chains

摘要： 我们采用介观模拟来研究通过多粒子碰撞动力学的溶剂中的活性聚合物。 我们研究线性链，其中头端或尾端单体施加一个向外或向其相邻单体方向的主动力，而其余单体是被动的。 我们发现，与柔性链不同，对于刚性链，主动单体的位置对链的结构和动态特性影响最小。 一个主动头端单体将其后面的链拉直，使主链变直——这一效应可以解释为活动引起的刚化。 相反，一个主动尾端单体将其推入链中，导致折叠。 这导致聚合物主链随时间的退相关加快，使主动运动的持续性降低。 这些效应无论是否包含流体动力相互作用都存在。 通过在周围流体中施加局部反作用力来包含流体动力学，而不是将前者平均分配给所有流体元素。 通过指定该反作用力在流体中的位置，我们可以调节活性聚合物的流体动力场，使其既具有收缩性又具有拉伸性。 有趣的是，产生的推动者和拉动者流场强烈受到聚合物链内部力传播的影响。 显示英文摘要

摘要： We employ mesoscopic simulations to study active polymers in a solvent via multi-particle collision dynamics. We investigate linear chains in which either the head or tail monomer exerts an active force, directed away from or towards its neighbor, respectively, while the remaining monomers are passive. We find that, in contrast to flexible chains, for stiff chains the position of the active monomer has minimal influence on both the structural and dynamic properties of the chain. An active head monomer pulls the chain behind it, straightening the backbone -- an effect that can be interpreted as activity-induced stiffening. In contrast, an active tail pushes into the chain, causing crumpling. This leads to faster decorrelation of the polymer backbone over time, rendering the active motion less persistent. These effects occur regardless of whether hydrodynamic interactions are included or not. Hydrodynamics is included by the imposition of a local counter-force in the surrounding fluid, as opposed to distributing the former equally to all fluid elements. By specifying the position of this counterforce onto the fluid, we can tune the hydrodynamic flow fields of the active polymers being both contractile and extensile. Interestingly, the emerging pusher- and puller flow fields are strongly influenced by the force propagation inside the polymer chain.