Valve types include Normally Open and Normally Closed valves, for use in fuel, hydraulic, or pneumatic applications.

阀门有常开和常闭两种，可用于燃油，液压或气动应用领域。

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In either case, each spin valve reacts to only one sort of molecule, so the chips can search simultaneously for as many types of molecules as they have spin valves.

ECONOMIST: Labs on a chip