The mantle's motions, analogous to those in a pot of boiling water, cool the mantle by carrying hot material to the surface and returning cooler material to the depths.

地幔的运动类似于一壶沸水的运动，它把热的物质带到表面，再把较冷的物质带到深处，从而使地幔冷却。

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The pillow uses a kind of LED material below the surface.

该枕头的表面下使用了一种 LED 材料。

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Such a quantity of material would have blocked the sunlight completely from reaching the surface, plunging Earth into a period of cold and darkness that lasted at least several months.

如此大量的物质会完全阻挡阳光到达地表，使地球陷入至少持续数月的寒冷和黑暗之中。

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There are certain scenarios, says Dr Lagace, where you might want to use a material because of its surface properties, but you might not want that property all the way through the material.

ECONOMIST: MONITOR

This microscopic scale and sensitivity allows the sensor to map a high-resolution image of electrical charge that occurs over the surface of a source material (for example a human finger), when it makes contact with a thin insulating surface (ie a plastic surface).

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Areas that in 2005 had looked like flows of material on the surface appeared on this occasion to have undergone some erosion.

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