For greater benefit, the railway freight requires operation of double-decked container trains, making the clearance under the railway overpass insufficient.

From purposes and clearance specifications of reserve runway, this paper points out the deficiencies in the airfield clearance regulations of reserve runway, and presents the composition of and the requirement for the reserve runway clearance area.

Detailed analysis was made on the civil airport clearance specification and its basis as well as main affecting factors.

On Childishness by Li Zhi in the Ming dynasty has connotations of five fields ; emptiness and nothing, naturalness , one moment of thought , for oneself and true feeling, namely, excluding traditional morality and ration.

Study on air purification by plasma combined with photocatalysis;

Nanocatalytic techniques for air purification;

Application of TiO 2 in photocatalytic air purification and antibacterial materials;

Introduce ACF load nanometer TiO2 several main methods,and the sole factors which influence to TiO2/ACF adsorption photochemical catalysis purification air performance,such as the TiO2 surface hydroxyl content,the crystal compose,the thin film crystal grain size,thin film thickness,TiO2/ACF relative surface and so on,are analized.

Studies on antibacterial and antiviral property of TiO_2 nanometer spray in air cleaning;

Application of electrostatic precipitation principle in the technique of air cleaning;

Selection of air cleaning means for hospital environment;