natural oil天然油
naturaladj.自然的;天然的;私生的
natural pour point depressant天然倾点降低剂
natural preservation solution天然保鲜液
natural rubber hot air drying天然橡胶热风干燥
natural oscillation frequency固有振荡频率
natural water surface coating自然水体生物膜
natural acous-tic impedance固有声阻抗
natural-like chemical fibre仿天然纤维
natural bituminized sandstone天然沥青砂岩