OK, so as much as Mobius strips and Klein-bottles are exciting and really cool, well, we can't use them in this class because we can't define flux through them.

与Mobius带相比较，克莱因瓶同样地有趣和巧妙，我们不能使用它，因为我们不能通过它们来定义通量。

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"If you think about it from the standpoint of a winery, you can get the same amount of wine in 40% fewer trucks in our packaging, compared to glass bottles, " explains Ed Klein, Tetra Pak's VP of public and environment affairs.

FORBES: Pinot Plastic