粉煤灰细度试验中应称取10g,准确至()g,倒入45μm方孔筛筛网上。 ["0.01","0.1","1","10"]
下列药材髓部有异型复合维管束的是() ["A、川牛膝","B、南沙参","C、何首乌","D、大黄"]
元素()会使钛及钛合金脆化,并且对于工业纯钛及α型钛合金的脆化作用明显大于α+β型和β型钛合金。 ["A、碳","B、氢","C、氧","D、氮"]
SBSI-D改性沥青25℃时针入度要求为()。 ["A、>100","B、80~100","C、60~80","D、40~60"]
为避免频繁的误告警,监控单元必须除位置告警和外部告警外其他告警项目都需进行()分钟的判断机制。 ["1","3","5","10"]
肺燥