Galvanic cell type hydrogen sensors and fuel cells belong to the former, and hydrogen pump, steam electrolyzer and membrane reactors to the latter.

原电池型的氢传感器和燃料电池属于前者，氢泵、蒸汽电解器和膜反应器属于后者。

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Experimental study has been made on substituting polytetrafluoroethylene oxygen electrode with silver catalyst for hydrogen cathode in chlorine-alkali electrolyzer in common use today.

本文试验了用含有银催化剂的聚四氟乙烯氧电极，代替目前氯碱电解槽中所使用的氢阴极。

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Great, but what did it cost to extract hydrogen from that water, and how much does the electrolyzer cost?

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Its systems bundle together fuel cells and an electrolyzer, another veteran technology, to generate their own fuel, hydrogen.

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