Part I: Experimental

Study on Improving the Turbidity Measurement of the Absolute Coagulation Rate Constant

“…When taking into account all of the uncertainties associated with the experiment itself, the total experimental errors may become even unacceptably larger. Thus, to avoid possible errors, the absolute rate constants derived from the turbidity measurement have been limited only to very small particles. , Although some researchers even applied the existing theories for the calculation of absolute coagulation rate constants of the suspensions of particles of a = 1000 nm by the turbidity measurement and compared the so-obtained data with the Smoluchowski theory, obviously it is difficult to judge the reliability of the conclusion from such a comparison.…”

Effect of the Hydrodynamic Radius of Colloid Microspheres on theEstimation of the Coagulation Rate Constant

“…对此, 各国研 究人员从不同角度进行了解释. 其中一些研究者怀 疑是重力的影响造成的聚集减慢 [12][13][14] . 欧空局科学 家 Folkersma 等 [12][13]15] [21] , 因而他们的结果和结论是不可 靠的.…”

A Direct Test on the Possibility of an Aggregate in Dispersion Being Disrupted by Shear Flow

“…In the absence of a method to directly check the role of shear flow in the coagulation, sometimes its influence on the coagulation process has to be estimated or analyzed theoretically only. For example, Folkersma et al (9,10) compared their experiments of perikinetic coagulation for 2-µm polystyrene lattices performed under microgravity (µg) with experiments under regular 1-g conditions and found that the coagulation rate under µg is 11.2 times greater than that under 1 g. Furthermore, as they showed, their finding implies that it is gravity which makes the coagulation rate much (over one order of magnitude) lower than its theoretical value (von Smoluchowski value). They assumed that this profound difference in coagulation rates was caused by free convection, which was thought to be inevitable on the ground.…”