how the cement grinding aids working ?

How the cement grinding aids working ? Normally the cement grinding works on two ways -------one is by the physical way cement grinding aids working ways is clean the mill ball surface static electricity , prevent the cement particles gather , Under use this condition of use cement grinding aids , the cement ball can work on the cement particles directly  (it will be wrap up with the particles if not) the ball can work high efficiency .output will be increase , meanwheal the residual will be less ,particles is smaller , strength will be increased . -------the another way is the chemical way . the cement grinding aids is a substance which speeds up a chemical reaction. it will reaction with the clinker chemical composition , this will depend on the clinker chemiccal composition and need test . --------normally , two ways , one is use the laboratory mini ball mill test and test the strength the another way is  the cement grinding aids to the water and test the strength anyway , this two ways not exactlly right data ,  the best way and actully result will be use factory ball mill test will get the exactlly right data .