Because oil is like a lock moisture barrier, if this layer protective film disappears, then the water will soon be air-dry the external environment.

因为油脂犹如锁住水分的一道屏障，如果这层保护膜消失不见，那么，水分很快会被外界环境风干。

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Ozone forms a protective layer between 12 and 30 miles above the Earth's surface.

臭氧在距地球表面12至30英里的地方形成一个保护层。

《柯林斯英汉双解大词典》

The birch tree has white bark, and this tough protective outer layer of the tree, this white bark, is waterproof.

桦树有白色的树皮，树上这个坚硬的保护外层，这个白色的树皮，是防水的。

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As you can tell, the device itself is encased in a ShockMount layer of protective armor, and we have to stress the "armor" aspect.

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In the past few years players have started to wear this layer of protective gear meant to feel like a second-skin in a sport that has bigger, faster and stronger athletes than ever.

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Piers, jetties and seawalls with a protective layer of marine growth absorb wave action better.

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