"Economics is the biggest barrier. "It's all pay as you go."

VOA: standard.2010.02.02

This cell can only be an effective barrier if there's no way to get past it.

这些细胞只有密不透风,才足以形成一道屏障

耶鲁公开课 - 生物医学工程探索课程节选

It's at equilibrium, under the new condition, that is with the barrier removed.

系统在新的状态下处于平衡，这个新的状态就是指隔板被取走了。

麻省理工公开课 - 热力学与动力学课程节选

The minimum wage is relatively high compared to the wage in France so it's a barrier when you don't have any qualifications and when you start your career."

VOA: standard.2009.11.12

The other is that this kind of adherence gives the tissue a property that's useful, in this case the property is it can serve as a barrier to nutrients from entering our body.

另外这种黏附,给予组织一种非常有用的属性,这种属性表现为组织成为,营养物质进入身体过程中的屏障

耶鲁公开课 - 生物医学工程探索课程节选

It was a mental barrier.

而是心理界限。

哈佛公开课 - 幸福课课程节选

when we remove the barrier and the gases mix, you know it's over.

当我们移走隔板并且气体混合后，我们知道事情就结束了。

麻省理工公开课 - 热力学与动力学课程节选

The problem it solves for the cell is how to do I make a barrier around myself to define what's in me and what's outside of me when most of what's around me and what's in me is water.

它为细胞解决的问题是,当我体外和体内大部分都是水情况下,我怎样在自己周围设置一个界线,来区分什么是体内的,什么是体外的

耶鲁公开课 - 生物医学工程探索课程节选