Oxygen and strontium isotopes, which are fixed in dental enamel at the time of tooth formation, were tested in 18 subjects.

在18件样本上检测了氧和锶的同位素。这两种元素在牙齿成型时，会固定在牙釉质上。

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The nitrogen Deoxo Vessel contains a fixed bed of free copper catalyst which removes oxygen from the nitrogen stream by oxidation of copper to copper oxides.

氮气脱氧罐中装有一个游离铜催化剂的固定床，通过将铜氧化成氧化铜把氧气从氮气中脱除。

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This might partly be relative with the fixed, extra and highly concentrated oxygen vacancies resulted from Y3 + doping, the mechanics of which were as described in the solid state chemistry.

这应部分地与固体化学所描述的Y3 +掺杂所造成固定、额外并且是高浓度的氧空位有关。

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