中文摘要：

应用激光粒度仪、影像分析及沉降分析技术研究了阳离子型聚丙烯酰胺（PAM）对混凝过程絮体的粒度、强度及分形维数等微观特性及絮体沉降速率的影响．结果表明，絮体的粒度、强度及分形维数等微观特性与阳离子型PAM的投加量有关，存在一个PAM的最佳投加剂量．在此最佳投加剂量下，系统内絮体的粒度与强度最大、分形维数最小、絮体沉降速率最大．

英文摘要：

The effect of cationic polyacrylamide（PAM） on the size, strength, fractal dimension and settling velocity of the flocs was studied by methods of the laser scattering, CCD image analysis and settling analysis. The experiments were carried out in a coagulation/flocculation system composed of kaolin suspension, aluminum sulphate, and cationic PAM. The results show that the size, strength, and the fractal dimension of the flocs are tightly related with the dosage of PAM, and that in the coagulation/flocculation process there is an optimum dosage of PAM , at which the size and strength of the flocs approach to the maximum, and the same applies to the settling velocity, while the fractal dimension of the flocs reaches the minimum.