<正> Available silicone was melted from coal gangue samples from Hancheng diggings through calcination, digestion, and other means. The best calcination tempera
<正> Huainan coal field as main object,investigation of Karstic hydrogeological con- ditions were developed in Huainan structureal unit,and the basic conditions
<正> Analyzed the factors which affected the coal and gas outburst,then established the corresponding indicator system.Built a dynamic set-pair analysis predict