The pozzolanic reactivity was determined by the hydration kinetics of pozzolanic reaction based on the fact that the hydration products of active SiO 2 and Al 2 O 3 with lime were soluble in dilute hydrochloric acid. The results show that the pozzolanic reaction of active SiO 2 and Al 2 O 3 of coal ashes follows apparent first-order kinetics. The reaction rate constant of FBC ashes is greater than that of PC ashes, while the activation energy of the former is lower than that of the latter. It is confirmed that the pozzolanic activity of fluidized bed combustion(FBC) ashes is significantly higher than that of PC ashes, and the reaction barrier of the former is lower than that of the latter, because the microstructures of FBC ashes, such as mineralogical composition, morphology and polymerization degree of [SiO 4 ] and [AlO 6 ] are more favorable to the pozzolanic activity development than those of PC ashes.

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Supergravity fields with high gravity acceleration can promote interphase ship velocity and convection velocity. Over the past decade, research has been devoted to enhancing electrochemical reactions by using supergravity fields. The enhancement of electrochemical reactions is ascribed to the acceleration of mass transfer and bubble separation. In this Minireview, the intensification kinetics of a supergravity field on mass transfer and bubble separation during electrochemical reactions are analyzed theoretically. The progress in terms the enhancement of electrochemical reactions (such as metal electrodeposition, water electrolysis, and chloralkali electrolysis) under a supergravity field is reviewed. The structures and properties of functional films electrodeposited under a supergravity field on both the cathode and the anode are summarized. The Minireview is helpful to understand the effect of the mechanism of the supergravity field on electrochemical reactions and to expand potential applications.

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