preservatives是什么意思

　　例句：

　　The juice contains no artificial preservatives.

　　这种果汁不含人工防腐剂。

　　Nitrates are used as preservatives in food manufacture

　　硝酸盐在食品加工业中被用作防腐剂。

　　She is also into building robots and testing preservatives in fast foods.

　　她还致力于机器人制造和快餐防腐剂检测。