lower surface

基本解释

When they descend to 50 meters or deeper, they must return to the surface slowly, to allow their bodies to readjust to the lower surface pressure.
当他们潜到50米或更深之后，必须缓慢的回到水面，才能使他们的身体重新将压力调节到低一些的水面气压。
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With preheating temperature enhancing, the peak value also increase, but cooling velocity decreases, resulting from the decrease of heat conductivity of sample lower surface.
随着预热温度的提高，电阻峰值也相应增大，但是样品下表面的热导出率下降，冷却速度下降；
The results indicated that three-dimensional open separation exists due to the cross flow around the afterbody, thicker boundary layer and the stronger adverse pressure gradient on the lower surface.
结果表明，上翘后体引起横向流动，使横向逆压梯度增大、下表面边界层增厚，导致后体出现三维开式分离流动；

Her partial prosthesis had worn through the bone on the lower surface of her knee.
NEWYORKER: Big Med
Water coming up from below will often have a lower pH than the surface water, because at depth there is no photosynthesis but plenty of respiration.
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Even a relatively small amount of gas a can cause big problems because a gas bubble will expand massively as it moves from high pressure at the seafloor to lower pressure at the surface.
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