Currents of the two sensors were detected when exposed to formaldehyde of different concentration.

分别检测两组气敏膜暴露于甲醛气体前后的电流变化，并计算其灵敏度。

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The area is prone to changes in winds and local currents, and ships can quickly become trapped, sometimes for weeks, when the concentration of pack ice increases.

BBC: HMS Protector approaches MS Fram