In some systems, foam at the surface may not cause a lot of damage, but the presence of a foam layer normally indicates extensive air entrainment.

在一些系统中，油液表面的泡沫不会造成很大的损害，但泡沫的存在说明相当量的空气滞留在油液当中。

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A heavy-duty foam layer helps absorb motion and shock from the sleep surface, enhancing firmness and durability.

重量级特制海绵层，有效吸收体重的冲击力及震荡，提升床垫的耐用度及承托力。

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The layered sheets each comprises a base sheet and a polyurethane foam layer.

本发明的层叠片包括基材片和聚氨酯发泡层。

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The Maya poured the chocolate drink back and forth between two containers so that the liquid had a layer of bubbles,or foam.

VOA: special.2010.02.17

Over that, they attach a half-inch layer of foam to give the structure some yield for little climbers.

WSJ: If Kids Can Play, Will Mom Shop?

Smaller bubbles make for a stable, uniform layer of foam.

FORBES: The Science of Small

In Afghanistan, the foam would be wrapped in a low-tech layer of chicken wire, then covered in a thin layer of concrete.

BBC: Aftermath of 1998 quake in northern Afghanistan