摘要
Janus颗粒利用自身非对称的表面性质建立浓度梯度场,并在其作用下产生自驱动,在微机电系统、生物学、流体力学等领域具有重要的应用.本文首先建立了模拟这一过程的数值模型,并由Pt-SiO2型Janus微球的实验数据确定了迁移速率匹配常数.随后,研究了3种相同体积、不同形状的Janus颗粒的自驱动,结果表明,与相同体积的球形Janus颗粒相比,圆柱及椭球状Janus颗粒具有更快的自驱动速度,同时燃料消耗更多.对于圆柱状颗粒,研究了粗细程度对圆柱状颗粒自驱动性能的影响,结果表明存在最优的直径与长度比(d/l=0.28).这一研究可为Janus颗粒具体应用提供理论基础.
Relying on its asymmetric surface characteristics, the Janus particle establishes concentration gradient and generates self-propulsion, which finds great applications in micro-electro-mechanical sys- tem, biology, fluid mechanics and other areas. In this paper, we firstly set up the numerical model to simulate this process, and determine the migration rate matching constant with the experimental data of Pt- SiO2 Janus microsphere. Then, we studied the self-propulsion of Janus particles in different shapes and fixed volume. The results show that cylindrical and ellipsoidal Janus particles have larger self-propelled velocities and more fuel consumption than those of spherical particle. For commonly used cylindrical par- ticles, we studied the effect of different aspect ratios on the self-propulsion. The results show that there is optimal condition （ the ratio of the diameter over length d/l is about 0. 28 ） , at which both self-propelled velocity and fuel consumption are maximum. This study may provide theoretical basis for practical application of Janus particles.
出处
《纳米技术与精密工程》
CAS
CSCD
2014年第5期340-345,共6页
Nanotechnology and Precision Engineering
基金
国家自然科学基金资助项目(21005058)
陕西省教育厅自然科学研究项目(11JK0530)
