The larger animals require less food per unit mass, more efficiently storing carbon than smaller animals.

较大的动物每单位质量需要的食物较少，却能比小型动物更有效地储存碳。

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Because of the tremendous amounts of energy liberated per unit mass in a nuclear detonation, temperatures of several tens of million degrees centigrade develop in the immediate area of the detonation.

由于核爆时每单位质量所释放的巨大能量，爆炸中心将产生数千万摄氏度高温。

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Direct yarn number is the mass per unit length of yarn; indirect yarn number is the length per unit mass of yarn.

定长制纱线细度是以纱线单位长度的重量表示的；定重制纱线细度是以纱线单位重量的长度表示的。

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You can see the atomic mass unit will be, excuse me. Let me go at it a different way.

你可以看到原子质量单位就是，不好意思，我们换个方式说。

麻省理工公开课 - 固态化学导论课程节选

Goodfellow's unit has so miniaturized the mass screening of such compounds that machines now replicate the countless experiments in pinhead-size droplets--1, 536 tiny wells on envelope-size plates--a process that formerly took humans untold man-hours.

FORBES: Magazine Article

Power density refers to the energy flow that can be harnessed from a given unit of volume, area or mass.

FORBES: Magazine Article

Damon plays Roy Miller, a U.S. soldier who leads a unit of men looking for weapons of mass destruction.

NEWYORKER: Green Zone