论文标题
在拉长颗粒的随机顺序吸附包装中的连接性渗透
Connectedness percolation in the random sequential adsorption packings of elongated particles
论文作者
论文摘要
数值研究了细长颗粒（圆锥形）二维包装中的连接性渗透现象。使用随机的顺序吸附（RSA）非晶格模型产生包装，并沿给定方向具有优先的颗粒方向。部分订购的特征是订单参数$ s $，$ s = 0 $，用于完全无序的膜（粒子的随机取向），沿水平方向$ x $的完全对齐的粒子的$ s = 1 $。粒子的纵横比（长度与宽度比）在[1; 100] $中的$ \ varepsilon \范围内变化。假设颗粒的核心壳结构进行了连通性的分析。 $ s $的值影响了包装的结构，远程连通性和电导率行为的形成。效果解释了粒子的定向自由度与排除体积效应之间的竞争。对于对齐的沉积，观察到电导率中的各向异性，并且沿对齐方向$σ_x$的值大于垂直方向上的值，即$σ_y$。在有限尺寸的包装中也观察到了渗透阈值定位的各向异性，但它消失在无限大型系统的极限中。
Connectedness percolation phenomena in two-dimensional packings of elongated particles (discorectangles) were studied numerically. The packings were produced using random sequential adsorption (RSA) off-lattice model with preferential orientations of particles along a given direction. The partial ordering was characterized by order parameter $S$, with $S=0$ for completely disordered films (random orientation of particles) and $S=1$ for completely aligned particles along the horizontal direction $x$. The aspect ratio (length-to-width ratio) for the particles was varied within the range $\varepsilon \in [1;100]$. Analysis of connectivity was performed assuming a core-shell structure of particles. The value of $S$ affected the structure of packings, formation of long-range connectivity and electrical conductivity behavior. The effects were explained accounting for the competition between the particles' orientational degrees of freedom and the excluded volume effects. For aligned deposition, the anisotropy in electrical conductivity was observed and the values along alignment direction, $σ_x$, were larger than the values in perpendicular direction, $σ_y$. The anisotropy in localization of percolation threshold was also observed in finite sized packings, but it disappeared in the limit of infinitely large systems.
