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1
β
25
15
10
5
0
0
1
2
3
4
q [nm
-1
]
Figure 5.11
Effect of DGMO content on scattering curves of MLO-based aqueous
dispersions at 25°C for an α ratio of 0 and with β values in the range of 0-25 (Yaghmur
et al., 2006b). The intensities have been shifted by a constant arbitrary factor for the
sake of visibility.
Figure 5.12a displays vesicles attached to the formed cubosomes, and in Figures
5.12b and 5.12c the electron beam is aligned with the [100] direction of the
dispersed particle, and the {110} and {200} planes contribute to the appearance
of a square motif. In Figures 5.12d and 5.12e the electron beam is oriented
along [111] and a hexagonal motif, formed by the {110} planes, is observed. It
should be pointed out that the particle was tilted in order to discriminate
between the Im3m and Pn3m space group (Sagalowicz et al., 2006, 2007).
Tilting by approximately 30° enabled access to the [110] axis of the observation
where the {110}, {200}, and {211} refl ections contributed (Figs. 5.12f and 5.12g).
More importantly, the absence of {1-11} and {1-1-1} demonstrated that the
space group was Im3m and not Pn3m (Sagalowicz et al., 2006). The lattice
parameter was found to be approximately 14 nm, a value in relatively good
agreement with that obtained from the SAXS analysis. In this sample, we also
observed a very limited number of particles with a lattice parameter in the
range of 10-11 nm. These particles likely had an internal Pn3m phase.
It was important to directly compare the confi ned nanoscaled internal
structure of the aqueous dispersions with those of the corresponding fully
hydrated nondispersed bulk systems. This was helpful in elucidating the infl u-
ence of DGMO on the internal nanostructures of the MLO-based aqueous
dispersions, and it was thus possible to better understand the observed struc-
tural changes in the dispersed systems. As an example, we compared the scat-
tering curve from the MLO-based dispersion (
25, gray line) with
those from the corresponding nondispersed MLO-DGMO bulk samples at
β
α
=
0 ,
β
=
=
25 with varying water content at 25°C (Fig. 5.13).
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