论文标题
硬立方体胶体悬浮液的主动微流变学
Active microrheology of colloidal suspensions of hard cuboids
论文作者
论文摘要
通过执行动态蒙特卡洛模拟,我们研究了硬核胶体长方体的各向同性悬浮液的微流变学。特别是,我们通过研究探针球形粒子的动力学来推断这些流体的局部粘弹性行为,该探针球形粒子的动力学并被外力拖动。该技术被称为主动微流变学,使人们可以在应用恒力时表征软材料的微观响应,该力的强度在这里跨越了三个数量级。通过调整立方体的几何形状,从碎肉到岩体以及系统密度,我们观察到不同的响应,这些响应是通过测量探针颗粒感知的有效摩擦来量化的。所得的摩擦系数在力弱且大于热力的力上表现出线性状态,而在中等力强度下观察到非线性的,非线性的,泛力的状态。
By performing dynamic Monte Carlo simulations, we investigate the microrheology of isotropic suspensions of hard-core colloidal cuboids. In particular, we infer the local viscoelastic behaviour of these fluids by studying the dynamics of a probe spherical particle that is incorporated in the host phase and is dragged by an external force. This technique, known as active microrheology, allows one to characterise the microscopic response of soft materials upon application of a constant force, whose intensity spans here three orders of magnitude. By tuning the geometry of cuboids from oblate to prolate as well as the system density, we observe different responses that are quantified by measuring the effective friction perceived by the probe particle. The resulting friction coefficient exhibits a linear regime at forces that are much weaker and larger than the thermal forces, whereas a non-linear, force-thinning regime is observed at intermediate force intensities.