【判断题】用 EDTA 滴定 Ca 2+ 、 Mg2+时,铬黑T能被溶液中的Fe3+、Al3+等离子封闭,可加入三乙醇胺掩蔽。
【单选题】At the news that his wife fell off the building, he rushed out of the house, ________his threeyearold boy ________. [ ]
【单选题】____ 可采用滚动轴承。 A. 大型低速柴油机曲轴 B.大型水轮发电机推力轴承 C. 轧钢机轧辊轴承 D.蒸汽涡轮发电机转子
【判断题】阻止辊子滚动的滚阻力偶矩随辊子承受载荷的增大而增大,可见采用滑动轴承比采用滚动轴承更佳。
【单选题】His ____ look on his face suggested that he was ____ to hear the _____ news.
A.
surprising, surprised, surprised
B.
surprised, surprising, surprised
C.
surprised, surprising, surprising
D.
surprised, surprised, surprising
【简答题】After he heard the news that his class team had lost in the , his d______ was great.
【单选题】VHF 设备的话筒有一个按压开关(PTT),此开关的作用是_____。(130758:第9章 VHF与VHF-DSC设备) (A-0,B-0,C-0,D-0,错误-0)
【单选题】Who told the man the news?