有很多沙粒是红色的，这是由于其表面有一层薄薄的铁，这些铁元素来自于空气中。

Many desert sands have a faint red color caused by a thin layer of iron that precipitates from the atmosphere and coats the grains. (Magnification 85x)

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脱氧是加进同氧的亲和力比铁更大的元素来实现的。

Their hemoglobin is both in high content, but also in high oxygen affinity.

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脱氧是加进同氧的亲和力比铁更大的元素来实现的。

Their hemoglobin is both in high content, but also in high oxygen affinity.

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