The cornea is the eye's clear outer surface that provides most of the visual power.

角膜是眼球外侧一层透明的膜，在视觉系统中非常重要。

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The bright red bowl, or arc, seen in this image traces the outer surface of the dense dust cloud encasing the young stars.

图中可见红色的弧形，它是一层致密气体的外层表面，这层气体则遮盖着那些年轻的恒星。

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In fact, it works much like Babbage's Difference engine, except that its digits are arrayed along the outer surface of a cylinder instead of horizontally along a loom-like rack.

事实上，它工作原理与巴贝奇的差分机相似，不同之处在于它的数字排列在圆柱形的外表面上而不是向织布机架那样水平分布。

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They thought it's just glass." In fact,the outer surface of the German entry was covered with solar panels.

VOA: special.2009.10.27

And shortly thereafter this thickening of the outer surface is dimpling in, its invaginating.

增厚的外胚层很快就,向内凹陷。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

During the two-and-a-half hour moon walk, the astronauts frolicked in the weightlessness of outer space and planted an American flag in the lunar surface.

VOA: standard.2009.07.16

T-cell, so that it would recognise the molecules found on the outer surface of melanomas.

ECONOMIST: Gene therapy has been shown to work on cancer

The forensics expert said the outer surface of April's coat was waterproof and would not shed fibres but the lining and fake fur of the hood could.

BBC: April Jones

While there are several peripherals that add keyboards and joysticks to smartphones, Sensus goes one step further by adding touch input to a device's entire outer surface.

ENGADGET: Canopy's Sensus gaming case protects your iPhone 4 / 4S, adds plenty of new touch sensors (update)