具有抗流感病毒作用的药物是() ["A、麻黄","B、桂枝","C、柴胡","D、葛根","E、细辛"]
汽车主要包括:() ["A、由动力驱动,具有四个或四个以上车轮的非轨道承载的车辆","B、整车整备质量超过400kg的三轮车辆","C、摩托车","D、无轨电车","E、有轨电车"]
旁路门的作用包括() ["A、可有可无","B、蒸汽管、给水管启动时暖管","C、某些管路在负荷低、流量小时,可开启旁路门而关闭主阀门","D、减小大直径闸板阀的开启力"]
循环流化床锅炉对物料回送装置有()基本要求。 ["A、无气体反串","B、煤质变化不大","C、物料流量可控","D、物料流动稳定"]
S1接口控制平面与用户平面类似,也是基于IP传输的,其传输网络层包括哪些?() ["SCTP层,","物理层,","IP层,","数据链路层"]
什么叫换热器的热负荷?