It uses a small computer worn on a person's arm to send electrical signals to activate sodium atoms.

它使用戴在人手臂上的小型计算机发送电信号来激活钠原子。

Sodium ions (sodium atoms with an electron missing, which makes them positively charged) are, however, five times the size of lithium ions.

然而，钠离子—在缺少一个电子的前提下，钠原子带正电—是锂离子的五倍大小。

The crystal structure of this compound is especially cool, because the helium and sodium atoms didn't just link up like in most molecules.

这种化合物的晶体结构特别不错，因为氦原子和钠原子的结合不像多数分子那样。

In a paper published in Nature Chemistry this year, researchers created a brand-new helium compound called sodium helide, which is one helium and two sodium atoms.

今年发表在《自然化学》上的一篇论文中说，研究者制造出了一种前所未有的含氦化合物，叫作氦化钠，由一个氦原子和两个钠原子构成。

As any high-school chemist knows, lithium and sodium are chemically similar. Sodium ions (sodium atoms with an electron missing, which makes them positively charged) are, however, five times the size of lithium ions.

任何一个高中的化学家都知道，锂和钠的化学性质很相似。然而，钠离子—在缺少一个电子的前提下，钠原子带正电—只有锂离子的五分之一大小。