The fixed ball valve is equipped with a floating valve seat. After the medium pressure, the valve seat moves and the sealing ring is pressed against the ball to ensure the sealing. Bearings are usually mounted on the upper and lower shafts of the ball, and the operating torque is small, suitab…

[Chinese instrument network instrument research and development] A few days ago, the research group of the Superconductivity and Energy New Materials Research Division of the Institute of Electrical Engineering of the Chinese Academy of Sciences Ma Yanwei used a multi-stage graphene composite…

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