GRADUAL GASIFYING OF LOW RANK COAL
analysis of rank correlation
characteristic equaltiy of rank
COAL RANK
热解碳
煤级
煤的变质程度
煤种
煤化度
煤化程度
煤蕴藏量
变质程度
煤阶
催化着火
煤质
coal rank distrib ution
coefficient of rank correlation
four-rank of three-step linear method
high sulphur occurring low rank coal