To plate metal is to cover it with a thin layer of gold, or silver, etc.

电镀金属就是把金属薄薄地覆盖上一层金或银等。

youdao

A metal or non-metal thin layer on the central area of front cover is in contact with said absorbing layer for transferring impact waves.

在约束玻璃板的外侧表面上涂有光能吸收涂层，与该层接触的前盖中部是金属或非金属的薄层，以传递冲击波。

youdao

Dab some antibiotic ointment onto a cotton swab (don't use your finger) and smear a thin layer onto the wound. Cover with an adhesive bandage.

用棉签(别用手指)蘸一些抗菌药膏在伤口处涂上薄薄的一层，用医用胶带盖上。

youdao

Drop several seeds over the surface of the pot and cover with a thin layer of vermiculite, a substance that can hold air, water and nutrients.

VOA: special.2009.04.21