The dynamics of dilute colloidal suspensions subject to time-dependent flow fields by conservative dichroism
The dynamics of dilute colloidal suspensions subject to time-dependent flow fields by conservative dichroism
复制标题
通过保守二色性研究稀胶体悬浮液的动力学随时间变化的流场
DOI：
10.1016/0021-9797(84)90454-5
复制
发表时间：
1984
影响因子：
9.9
通讯作者：
G. Fuller
中科院分区：
文献类型：
--
作者：
P. Frattini;G. Fuller
描述了一种装置，它允许同时测定光学各向异性的稀释悬浮液的保守线性二色性和平均取向角，非吸收球体受到瞬态剪切场的影响。二色性的大小反映了粒子沿其平均取向角的排列程度，及时测量二色性可以直接得到粒子的旋转运动。本实验将光弹性调制器应用于一种新型的光学列车；探测器信号的一次谐波和二次谐波是二色性和取向角的独立函数，它们作为时间的函数被同时测量。初步数据的稀释悬浮液的膨润土在90%的甘油和10%的水经受瞬时简单剪切，以说明该技术。瑞利散射理论和杰弗里在蠕变单剪切中刚性球体动力学的解充分地描述了这些数据的定性特征。
An apparatus is described which permits simultaneous determination of the conservative linear dichroism and the average orientation angle of a dilute suspension of optically anisotropic, nonabsorbing spheroids subjected to a transient shear field. The magnitude of the dichroism reflects the degree of alignment of the particles along their average orientation angle and measurement of this property in time directly obtains the rotational motion of the particles. This experiment makes use of a photoelastic modulator in a novel optical train; the first and second harmonics of the detector signal, which are independent functions of the dichroism and orientation angle, are measured simultaneously as functions of time. Preliminary data on a dilute suspension of bentonite in 90% glycerine and 10% water subjected to an instantaneous simple shear are presented to illustrate the technique. The qualitative features of these data are adequately described by the Rayleigh scattering theory coupled with Jeffery's solution for the dynamics of a rigid spheroid in a creeping simple shear.