Lamura A, Burkhardt T W, Gompper G
Istituto Applicazioni Calcolo, CNR, Sezione di Bari, via Amendola 122/D, 70126 Bari, Italy.
Phys Rev E Stat Nonlin Soft Matter Phys. 2004 Nov;70(5 Pt 1):051804. doi: 10.1103/PhysRevE.70.051804. Epub 2004 Nov 18.
Using an algorithm for simulating equilibrium configurations, we study a fluctuating helical polymer either (i) contained in a cylindrical pore or (ii) wound around a cylindrical rod. We work in the regime where both the contour length and the persistence length of the helical polymer are much larger than the diameter of the cylinder. In case (i) we calculate the free energy of confinement and interpret it in terms of a wormlike chain in a pore with an effective diameter that depends on the parameters of the helix. In case (ii) we consider the possibility that one end of the helical polymer escapes from the rod and wanders away. The average numbers of turns at which the helix escapes or intersects the rod are measured in the simulations, as a function of the pitch p(0) . The behavior for large and small p(0) is explained with simple scaling arguments.
我们使用一种用于模拟平衡构型的算法，研究了一种波动的螺旋聚合物，它要么（i）包含在圆柱形孔中，要么（ii）缠绕在圆柱形杆上。我们在这样一种情况下进行研究，即螺旋聚合物的轮廓长度和持久长度都远大于圆柱体的直径。在情况（i）中，我们计算了受限自由能，并根据在具有有效直径的孔中的蠕虫状链来解释它，该有效直径取决于螺旋的参数。在情况（ii）中，我们考虑了螺旋聚合物的一端从杆上逸出并游走的可能性。在模拟中测量了螺旋逸出或与杆相交时的平均匝数，作为螺距p(0)的函数。通过简单的标度论证解释了大p(0)和小p(0)时的行为。
