Biomedical Engineering Reference
In-Depth Information
R
ss
R
ss
R
s
R
s
R
s
R
p
Z
w
C
d
R
p
Z
w
C
d
R
p
Z
w
C
d
R
s
R
s
R
s
R
ss
R
ss
Single unit-
(i - 1)
(i)
(i + 1)
FIGURE 7.4
An equivalent electronic circuit for a typical IPMNC strip obtained by an
impedance analyzer.
10000
1000
100
10
1
0.1
0.01
0
2
4 6
Penetration depth (
ยต
m)
8 0 2 4
FIGURE 7.5
Measured surface resistance,
R
, of a typical IPMNC strip, as a function of
s
platinum particle penetration depth.
, of a typical IPMNC strip as a function of platinum particle penetration
depth. Note that SEM was used to estimate the penetration depth of platinum into
the membrane.
The four-probe method was used to measure the surface resistance,
resistance,
R
s
, of the
IPMNCs. Obviously, the deeper the penetration of metallic particles is, the lower
the surface resistance is.
Figure 7.6 depicts measured chronoamperometry responses of a typical IPMNC
sample in which the current response is recorded after a step potential is applied. It
should be noted that the important physical phenomena occurring in the vicinity of
R
s
