Biomedical Engineering Reference
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the pH value of the initial precursors, a
c in Fig. 3.6), a peak at
20 ppm is present and becomes stronger and sharper. Therefore, it
was assigned to formation of resoacetophenone, representing alkyl
carbon (-CH
) [37].
3
13
C CPMAS spectra of resorcinol and furfural aerogels obtained
at a spinning speed of 3 kHz (a) without acetic acid catalyst
(pH = 6.9), (b) with acetic acid (pH = 4.8), and (c) with acetic
acid (pH = 4.1).
Figure 3.6
Figure 3.7
SAXS scattering curves obtained for CAs: (a) CA4.1, (b) CA4.5,
(c) CA4.8, and (d) CA5.2. The inset is a plot of ln
I
(
q
) vs.
q
2
which yields the radius of gyration
of the pores within the
aerogel structure determined from the slope.
R
G
