preservativen.防腐剂；预防法；预防药adj.保存的；有保存力的；防腐的preservative substance防腐剂,杀菌剂preservative injection防腐注射preservative-treated防腐处理preservative mechanism防腐机制preservative efficiency防腐效率preservative mechanisim应用preservative engine oil防护机器油preservative measurement防腐措施preservative combination防腐合剂preservative and sweetener防腐剂和甜味剂