Studies of sulfonated phenol-formaldehyde resins: preparation of HJ-superplasticizers and their effects on workability and mechanical strength of concretes是什么意思_Studies of sulfonated phenol-formaldehyde resins: preparation of HJ-superplasticizers and their effects on workability and mechanical strength of concretes在线翻译_英语_读音_用法_例句