When a planar shock wave is sweeping a density layer, the deformation of the density interface and the wave configurations can occur.

运动激波在密度间断层传播时，引起密度分界面的变形，相应激波形状发生改变。

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This layer - with an oxygen density probably about 5 trillion times less than on Earth - was "too thin to be remotely detected", said Ben Teolis of the Southwest Research Institute in San Antonio.

圣安东尼奥市西南研究所的本·特奥里斯（Ben Teolis）说，这个大气层——其含氧量可能不亚于目前地球的5万亿倍——是“如此稀薄一致难以遥远地探测。”

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The results show that the grain size of tin gradually gets smaller while that of alloy layer gets bigger and bigger with the increasing of current density.

结果表明，随着电流密度的增加，电沉积的锡晶粒度逐渐细化，合金层的晶粒度有变粗的趋势。

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This melt water has a relatively low density, so it accumulates in the top layer of the ocean.

BBC: Melt may explain Antarctica's sea ice expansion

Waratek will let an enterprise swap out the middle layer of its software stack without changing its applications and significantly increase the density in data centers.

FORBES: Lousy London Economy Good For A Data Center Density Enhancer

As we learned when the console was initially announced, the Wii U's "proprietary high-density optical discs" hold up to 25GB of data -- equivalent with that of Sony's single-layer Blu-ray format on the PlayStation 3, and much larger than the Xbox 360's dual-layer DVD format.

ENGADGET: Take a very, very close look at the round-edged Wii U proprietary discs