研制的几种涂膜保鲜剂，具有半透性膜的特性，履盖于果实表面，既可减少果实水分的蒸发，又能保持一定的通透性。保鲜剂的组成不同、膜的通......

In many arid and semiarid regions,saline playas represent a significant source of unconsoli-dated sediments available fo......