蒸汽往复泵在()时有冲击声或振动。 ["汽缸活塞或汽阀磨损过度","阀门损坏,或者水泵装配不当","阀杆的密封过紧,或机械部分卡住","汽缸有裂缝"]
作物的库
控制细胞膜上通道开闭的因素有() ["渗透压","pH值","激素等化学物质","膜电位","温度"]
血液中多种凝血因子合成均在() ["肝脏","小肠","血细胞","骨髓","心肌"]
蒸汽往复泵走不动,机械部分的原因可能是() ["往复速度过快","主轴承,十字头、活塞销、曲轴等太松","阀杆密封过紧或者机械部分被卡住","汽缸活塞或汽阀磨损过度"]
()和()促进电信业务全球化。