Abstract: Disclosed is a method for enhancing thermal energy storage performance of industrial grade hydrated salts based on phase change, comprising: heating an aqueous system of industrial grade hydrated salts containing 105-130 percent (%) by mass of m0 industrial grade hydrated salt to m0, taking a sample for differential scanning calorimeter testing and recording its melting enthalpy as ?H1; melting and adding water into, or melting and evaporating the residual aqueous system of industrial grade hydrated salts or the residual industrial grade hydrated salts system with a mass of m1 to increase or decrease the mass by 0.4-0.8% m0 until a melting enthalpy ?Hn of a sample that taken from the residual aqueous system of industrial grade hydrated salts with a mass of mn satisfies ?H2< . . . <?Hn>?Hn+1.

Abstract: Disclosed is a method for enhancing thermal energy storage performance of industrial grade hydrated salts based on phase change, comprising: heating an aqueous system of industrial grade hydrated salts containing 105-130 percent (%) by mass of m0 industrial grade hydrated salt to m0, taking a sample for differential scanning calorimeter testing and recording its melting enthalpy as ?H1; melting and adding water into, or melting and evaporating the residual aqueous system of industrial grade hydrated salts or the residual industrial grade hydrated salts system with a mass of m1 to increase or decrease the mass by 0.4-0.8% m0 until a melting enthalpy ?Hn of a sample that taken from the residual aqueous system of industrial grade hydrated salts with a mass of mn satisfies ?H2< . . . <?Hn>?Hn+1.

Abstract: Disclosed are methods for preparing high-purity boehmite and porous gamma-alumina nano-powder, comprising: adding aluminum isopropoxide into water and stirring the aluminum isopropoxide added water, then adding aluminum hydroxide generated by hydrolysis of high-purity aluminum powder into that stirred water, stirring that aluminum hydroxide added water to obtain a mixed system; carrying out hydrothermal reaction on the mixed system, performing centrifuging, washing, drying and crushing to the reacted mixed system, obtaining high-purity boehmite; calcining the high-purity boehmite to obtain porous gamma (?)-alumina nano-powder.