特殊用法crude oil upgrading1.原油预处理cryogenic upgrading1.深冷提纯gasoline upgrading1.汽油提(高)质(量); 汽油改质hexane upgrading1.己烷提级; 己烷改性octane upgrading1.辛烷值提级upgrading of boiler weld1.锅炉焊缝加强