They also discovered that the helium in the balloons would last for six hours.

他们也发现汽球中的氦气有效时限可达六小时。

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"For example,if we were working on combinations of six, there may be six balloons."

VOA: standard.2010.08.10

"But with those six balloons, one is green,five are yellow or they may have three of them to be large and three of them to be smaller, or we may have one with a star on it.

VOA: standard.2010.08.10

The hand, which is said to be a "feat of microscale mechanical systems (MEMS), " measures just one millimeter across when closed into a fist, features four "fingers" made of six silicon wafers each, and touts four gas-powered balloons acting as the muscles at the wafers' joints.

ENGADGET: Researchers craft microscale robotic hand for surgeries