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Structural analysis in the range of characteristic sizes from 1 nm to ~1.5 µm was performed for SiO2–TiO2 aerogels prepared in supercritical CO2, isopropanol, hexafluoroisopropanol, or methyl-tert-butyl ether using small-angle X-ray scattering and neutron scattering complementary methods. A two-level model that accounts for scattering by individual inhomogeneities and their aggregates, which have fractal properties, satisfactorily describes the aerogel structures over the entire range of scales. It is shown for the first time that the titania concentration is the key factor in the small-angle neutron and X-ray scattering by SiO2–TiO2 aerogels. The phase composition of an aerogel does not significantly affect the aerogel structure in the range of scales from 1 nm to ~1.5 µm, as probed by small-angle X-ray and neutron scattering.

The evolution of the Ti–Zr alloy microstructure (residual stresses, as well as microstress) during annealing after severe plastic deformation is reported. A strong residual macro-stresses relief starts at temperature of 530–540°C. A steep decrease continues up to 580°C and a further slight decrease up to 600°C. Microstrain (caused by the high dislocation density created by equal channel angular pressing) is almost constant up to 300°C, and then begins to decrease gradually due to recovery. The microstrain decrease accelerates at 560°C and is finished at 580°C. Most probably, this is caused by recrystallization. The information obtained is important for possible microstructure modifications and tuning via post-process heat treatment.

The internal structure of empty porous micro- and macroporous magnetic glasses and the related nanocomposites containing NaNO2 and KNO3 embedded in pores of the glasses has been investigated using small-angle neutron scattering. The characteristic sizes of magnetite particles in matrices and the sizes of nanoparticles embedded in ferroelectric materials have been estimated. It has been shown that, for microporous glasses in the momentum transfer range 0.35 nm–1 < Q < 1.7 nm–1, the dependence of the small-angle neutron scattering intensity on the momentum transfer has two characteristic regions: the first region corresponds well to the Porod’s law Q –4 (smooth surface), and the second region is consistent with the mass fractal reflecting the internal structure of channels in the microporous glass. For macroporous glasses over the entire momentum transfer range 0.35 nm–1 < Q < 1.7 nm–1, the scattering intensity is described by the dependence I(Q) ~ Q –n with α = 3.96 ± 0.02; i.e., in these glasses, there is a system of channels with sufficiently smooth surfaces.

This study is devoted to investigation of the micro- and mesostructure (including fractal properties) of porous zirconia glasses synthesized by precipitation from zirconium n-propoxide solutions in the presence of different hydrolyzing-agent (H2O) quantities at different temperatures. Analysis of small-angle neutron, ultra-small-angle neutron and X-ray scattering, scanning electron microscopy allows concluding that the synthesized glasses are complex systems with a three-level hierarchical fractal structure. It is revealed that both the temperature of synthesis and the H2O concentration in the initial solution significantly affect the structural characteristics of the glasses.