物理化学学报 >> 1997, Vol. 13 >> Issue (01): 20-27.doi: 10.3866/PKU.WHXB19970105

研究论文 上一篇    下一篇

剪应力下弱作用势胶体颗粒聚团的特点

李敬生,P.Mark Rodger   

  1. 西安建筑科技大学冶金系,西安 710055|Dept.of Chem,Univ.of Reading,U.K
  • 收稿日期:1996-05-31 修回日期:1996-09-20 发布日期:1997-01-15
  • 通讯作者: 李敬生

Characteristics of Colloidal Aggregates with Weakly Bound Potential under Shear

Li Jing-Sheng,P.Mark Rodger   

  1. Department of Metallurgy,Xi'an University of Archtecture and Technology|Department of Chemistry,University of Reading,U.K
  • Received:1996-05-31 Revised:1996-09-20 Published:1997-01-15
  • Contact: Li Jing-Sheng

摘要:

探讨了不同剪应力下,具有Lennard-Jones势的胶体颗粒聚团的结构特性,包括簇团的大小分布,径向分布函数,分形维数和原子配位数.研究表明,在弱作用力下,胶体簇团的分布随剪应力的增加而趋向小簇团一边;径向分布函数曲线随剪应力的增加而降低,且在近程距离内降低得最多;分形维数随剪应力的增加表现为先增加后减小的趋势,其值随模拟条件的不同而在1.9-2.4之间变动.剪应力“场”对分形维数的大小没有太大的影响,但在较大的剪应力下,簇团被明显拉长,且其主轴对X轴(剪应力方向)产生偏离.

关键词: 胶体, 聚团, 计算机模拟

Abstract:

Research on characteristics of colloidal aggregates with Lennard-Jones potential under shear has been carried out. The features included cluster size distribution, radial distribution function, fractal dimension and coordination numbers. It revealed that cluster size distribution approached to smaller size, radial distribution function and coordination number reduced graduately with increasing shear rates. When shear rates increased, fractal dimension ranging 1.9-2.4 increased first then decreased slightly. Shear did not change fractal dimension obviously, however (clusters were stretched at X (shear rate) direction and deviated from the X direction at high shear rates.

Key words: Colloids, Aggregates, Computer simulation