关于阴性对比剂的叙述,错误的是()
A.氧气属阴性对比剂
B.空气有产生气体栓塞的危险
C.空气在器官内吸收较慢
D.二氧化碳的溶解度较大
E.有效原子序数大
参考答案:E
Don't worry. I can look after your pet ___ while you are away. [ ]
A.careful enough
B.carefully enough
C.enough careful
D.enough carefully
冷粘法是采用带有自粘胶的防水卷材,因此既不需要胶粘剂,也不用热施工就可以进行黏结。( )