Colloid Particle Adsorption on Partially Covered (Random) Surfaces.
Colloid Particle Adsorption on Partially Covered (Random) Surfaces.
复制标题
部分覆盖（随机）表面上的胶体颗粒吸附。
DOI：
10.1006/jcis.2001.7601
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发表时间：
2001
影响因子：
9.9
通讯作者：
E. Musial
中科院分区：
文献类型：
--
作者：
Z. Adamczyk;P. Weroński;E. Musial
采用随机顺序吸附（RSA）方法模拟了胶体颗粒在具有相同表面电荷符号的小颗粒表面上的不可逆吸附。通过数值模拟确定了不同粒径比λ =a(l)/a(s)时大颗粒的初始通量与小颗粒表面覆盖率θ(s)的关系。这些数值结果用一个由尺度粒子理论导出的解析公式来描述。对大颗粒的长期吸附动力学也进行了模拟。这允许人们根据外推确定干扰覆盖θ(l)（无穷）作为λ参数在固定较小的粒子覆盖θ(s)的函数。发现干扰覆盖θ(l)（无穷大）对粒径比大于4时非常敏感。除了得到θ(l)（无穷大）外，数值模拟还允许人们确定干扰状态下大颗粒单层的结构，这与单分散系统的观察结果有很大的不同。理论预测表明，通过研究较大的胶体颗粒吸附动力学和单层结构，可以定量表征表面非均质性，例如显微镜下不可见的较小尺寸污染物或较小颗粒的存在。版权所有2001学术出版社
The random sequential adsorption (RSA) approach was used to model irreversible adsorption of colloid particles at surfaces precovered with smaller particles having the same sign of surface charge. Numerical simulations were performed to determine the initial flux of larger particles as a function of surface coverage of smaller particles θ(s) at various size ratios lambda=a(l)/a(s). These numerical results were described by an analytical formula derived from scaled particle theory. Simulations of the long-time adsorption kinetics of larger particles have also been performed. This allowed one to determine upon extrapolation the jamming coverage θ(l)(infinity) as a function of the lambda parameter at fixed smaller particle coverage θ(s). It was found that the jamming coverage θ(l)(infinity) was very sensitive to particle size ratios exceeding 4. Besides yielding θ(l)(infinity), the numerical simulations allowed one to determine the structure of large particle monolayers at the jamming state which deviated significantly from that observed for monodisperse systems. The theoretical predictions suggested that surface heterogeneity, e.g., the presence of smaller sized contaminants or smaller particles invisible under microscope, can be quantitatively characterized by studying larger colloid particle adsorption kinetics and structure of the monolayer. Copyright 2001 Academic Press.