helium怎么读，helium什么意思，helium短语和例句

1.Firstly, all existing supplies of helium ought to be conserved and released only by permit, with medical uses receiving precedence over other commercial or recreational demands.

首先，所有现有的氦供应应该被保存下来，并且只有在获得许可的情况下才能释放，医疗用途应优先于其他商业或娱乐需求。

2.Helium is the by product of millennia of radioactive decay from the elements thorium and uranium.

氦是钍和铀元素数千年放射性衰变的副产品。

3.The balloon may be filled with helium or hydrogen.

气球中可能会充满氦气或者氢气。

4.A regulatory agency should ensure that helium is used carefully.

应该有一个监管机构确保氦的使用是谨慎的。

5.Helium is a very light gas.

氦是一种很轻的气体。

6.It contained very little hydrogen and helium.

它含有非常少的氢和氦。

7.However, the amount of helium in the universe, as measured by spectroscopy, suggests that there are far more baryons in the universe than estimates based on galactic luminosity indicate.

然而，通过光谱学测量，宇宙中氦的数量表明，宇宙中重子的数量要比基于星系光度所估计的要多得多。

8.Hydrogen turns into Helium, which releases energy.

氢变成氦的时候会释放能量。

9.The Jovian planets have very thick atmospheres consisting of varying amounts of hydrogen, helium, methane, and ammonia.

木星的行星有非常厚的大气层，且由不同数量的氢、氦、甲烷和氨等元素组成。