阈电位指能引起Na+通道大量开放而引发动作电位的
A.临界膜电位数值
B.最大局部电位数值
C.局部电位数值
D.临界超射值
E.临界锋电位数值
参考答案:A
They did everything in their power to save the building dating back to the Qing Dynasty, but their efforts were _______.
A.in turn
B.in time
C.in vain
D.in need
重水(D2O)的离子积为1.6×10-15,可以用pH一样的定义来规定pD=-lgc(D+),以下关于pD的叙述正确的是
A.重水的pD=7.0
B.含0.01mol NaOD的D2O溶液1L,其pD=12.0
C.溶解0.01molDCl的D2O溶液10L,其pD=2.0
D.在100mL 0.25mol/L的DCl重水溶液中,加入50mL 0.2mol/L NaOD的重水溶液,其pD=1.0