v"
17
18
19
20
k
v
″
(H
2
)
2.8 ± 0.3
3.6 ± 0.3
4.5 ± 0.4
5.1 ± 0.4
k
v
″
(N
2
)
1.3 ± 0.1
1.8 ± 0.2
2.2 ± 0.2
2.8 ± 0.3