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。

youdao

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。

youdao

The explosive potential (energy content per unit mass) of hydrogen is about twice that of the methane in natural gas.

氢的爆炸潜能(单位质量含有的能量)大约是天然气中甲烷的两倍。

youdao

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