【单选题】3单选Portland cement is termed a hydraulic cement because its hardness develops by chemical reaction with.
【简答题】等价类划分有两种不同的情况,有效等价类和( )
【单选题】Portland cement is termed a hydraulic cement because its hardness develops by chemical reaction with .
【多选题】Portland cement is made by heating a mixture of ( ) and ( ), or other similar bulk composition.
【简答题】( ) hardens
slowly and takes long time to add to the strength in Portland cementA. C3S B. C2S C. C3A D. C4AF
【判断题】等价类划分有两种不同的情况:有效等价类和无效等价类。
【简答题】The mass percent of tricalcium silicate ( ) is 50% in Portland cement, which acts as the binding agent in concrete. Calculate the mass percent of calcium in this Portland cement.
【单选题】患者,男性,岁。因胸痛就诊,既往有心绞痛十年。鉴别急性心肌梗死与心绞痛,症状的主要区别是