If the vehicle in the unfortunate circumstances of a collision, has to be able to maintain the security of the hydrogen which means more mass, which means a lot of the efficiency is being squandered What's the environmental impact of hydrogen production?

如果车辆,在碰撞中发生了不幸，要仍然能够保持氢气的安全性的话,意味着需要更多的质量，也就是说大部分效率被浪费了,制氢对环境有什么影响呢？

麻省理工公开课 - 固态化学导论课程节选

Once a week we assembled the homeland security team which meant in the later part of the administration The Secratary of Homeland Security, 911 which was a position was created in the year after 911.

每个星期,还会组织一次国土安全组的人开会,意味着会议的第二部分,会见国土安全部部长，这个职位是在,之后的一年才创立的。

普林斯顿公开课 - 国际座谈会课程节选