【单选题】(第四章)制造热锻模,常采用的材料是 。
【单选题】He had no sooner returned ____ he bought a new house.
【判断题】( )建筑群配线架(CD)到建筑物配线架(BD)间的距离不应超过2000 米。
【单选题】He had no sooner finished his speech _____ he withdrew.
【单选题】在 60 MHz 核磁共振仪器上,TMS 和一物质分子的某质子的吸收频率差为 120 Hz,则该质子的化学位移δ值为
【单选题】局麻药中间联接部分的碳原子数以几个为好( )