Carbon dioxide is inexplicably a mere trace gas when it should be the bulk of the air, as it is on other planets.

令人费解的是，二氧化碳理应像在其他行星那样成为大气的主要成分，却仅仅是一种示踪气体。

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A flow injection on-line coprecipitation system has been coupled with an atomic absorption spectrometric system for the determination of trace calcium in bulk of cobalt and nickel matrix.

流动注射在线共沉淀分离富集-火焰原子吸收法现场快速测定钴镍基体中的微量钙。

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