【单选题】淬火钢回火温度升高至400°C时,M完全分解,形成仍保持针状的F和与其无共格关系的细小的粒状和片状的全部θ相的机械混合物。,称为:
【简答题】He ran as fast as he could and reached the train station with _______a few seconds to spare. [A] hardly [B ] over [C] only [D] even
【判断题】直接耦合放大电路存在零点漂移主要是由于晶体管参数受温度影响。
【多选题】充型能力不足,容易产生浇不足、冷隔等缺陷。为防止这些缺陷的产生,可采取的措施有( )。