Several chemicals have displaced the oxygen.

有几种化学物质取代了氧气。

youdao

youdao

youdao

She founded the Oxygen media company, the Oprah's Angel Network charity and the Harpo film,television and radio production company.

VOA: special.2010.04.16

That is metallic sodium that would keep in kerosene so it doesn't react with the oxygen in the air.

金属钠应该保存在没有中,这样它就不会和空气中的氧气反应了。

麻省理工公开课 - 固态化学导论课程节选

So, if we compare the sulfur to the oxygen, the oxygen it turns out is more electronegative and that is what holds the negative charge in this molecule.

因此，如果我们来比一下硫和氧，氧应该有更高的电负性,而在这个分子中它确实有负的电荷。

麻省理工公开课 - 化学原理课程节选

Floating sensors hold the oxygen to between 2 and 2.5 parts per million of water.

FORBES: Muckraker

Floating sensors hold the oxygen to between 2.0 and 2.5 parts per million of water.

FORBES: Muckraker

When the oceans ran out of iron, the oxygen was free to accumulate in the air.

NEWYORKER: The Martian Chroniclers