Thus, the natural secondary forest in Taihang Mountain plays a very import role in maintaining the equilibrium of CO2 and O2, regulating climate, cleaning air and so on.

Thinks that the total actuating pressure of an air curtain consists of wind pressure, thermal pressure, mechanical pressure and equilibrium pressure.

Study results show that gasification can proceed deep in the bed and the gasifying reaction can approach chemical equilibrium at a proper ratio of spouting to fluidizing air.