Biomedical Engineering Reference
In-Depth Information
fractal dimension on the sensing surface indicates an increase in the degree of heterogeneity
on the sensing surface.
Shinde et al. (2007)
used scanning electron micrographs to analyze the surface morphology stud-
ies of the ZnO films sprayed on glass substrates. These authors noted that the grain size increased
with an increase in the sprayed precursor solution [S
1
(0.1 M), to S
2
(0.15 M), to S
3
(0.25 M) zinc
nitrate solution]. This is consistent with the results obtained by
Korotcenko et al. (2001)
.
Figure 10.1a
shows the binding and dissociation of 0.2 volume percent LPG in the gas phase
to sample S
1
(0.1M zinc nitrate solution used in the spray pyrolysis method) (
Shinde et al.,
2007
). A dual-fractal analysis is required to adequately describe the binding and the dissoci-
ation kinetics.
Tables 10.1
and
10.2
show (a) the binding rate coefficient,
k
, and the fractal
60
35
30
50
25
40
20
30
15
20
10
10
5
0
0
0
100
200
300 400
Time (s)
500
600
700
0
100
200
300 400
Time (s)
500
600
700
A
B
16
14
12
10
8
6
4
2
0
0
100
200
300
400
500
600
C
Time (s)
Figure 10.1
Binding of samples S
1
,S
2
, and S
3
(LPG; liquid petroleum gas) to zinc oxide (ZnO) films prepared by
the spray pyrolysis method onto a glass substrate (
Shinde et al., 2007
). Influence of zinc oxide
concentration (0.1-0.3 M) solution: (a) 0.1M, sample S
1
, (b) 0.15M, sample S
2
, (c) 0.3M, sample
S
3
. When only a solid line is used (—) then a single-fractal applies. When both a dotted (- - -) and a
solid line (—) is used, then the dotted line is for a single-fractal analysis, and the solid line is for
a dual-fractal analysis. In this case, the dual-fractal analysis provides the better fit.
