So if we want to talk about the volume of that, we just talk about the surface area, which is 4 pi r squared, and we multiply that by the thickness d r.

如果我们要讨论它的体积，我们要用的是表面面积，也就是４πｒ的平方，乘以厚度ｄｒ

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The HPS has issued its standard, Surface and Volume Radioactivity Standards for Unconditional Clearance.

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Microplastics have larger surface to volume ratios, potentially facilitating contaminant exchange and have been shown to be ingested by a range of organisms.

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But as an object gets smaller, the ratio between its surface area and its volume rises.

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