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Comparative studies of the optical properties and photostability of pristine microsized TiO2 powder and modified with its own nano- and hollow particles have been carried out. It was established that the reflection coefficient (ρ) decreases down to 3.5% in the visible region and increases up to 3–4% in the near-IR region at a 3 wt% concentration of nano- and hollow TiO2 particles. Powders irradiation with intensive solar radiation causes an appearance of absorption bands with maxima at 420 nm and 800–1200 nm in the difference diffuse reflection spectra. In the spectra of the powder modified with hollow particles, the bands with lower intensity shift to shorter wavelengths—to 410 and 750–800 nm. An increase in irradiation time from 5 to 40 h results in the intensity increasing of such bands. It was found that a greater effect was obtained upon modification with hollow particles in comparison with TiO2 nanoparticles. Photostability of the powders modified with hollow particles is more than 4.6 times higher than for unmodified one and it was compared with powders modified with SiO2 and ZrO2 nanoparticles. An explanation of the results obtained is given. [ABSTRACT FROM AUTHOR]

High-temperature annealing of hydrated forms of calcium silicate produced in the multicomponent system CaCl 2 Na 2 SiO 3 H 2 O yields the formation of a heterophase structure containing high-temperature phases of pseudo-wollastonite and silica. Under these conditions, it is observed that there is an increase in the calcium silicate crystal lattice energy, particle size, reflection coefficient in the visible and near-IR spectral ranges, and radiation stability of the synthesized powders. The improved characters make the work useful, interesting and important. [ABSTRACT FROM AUTHOR]

The radiation hardness of three types of BaTiZrO3 coatings obtained by synthesis from the powder mixtures BaTiO3 + ZrO3, BaCO3 + TiO2 + ZrO3 (micron size), and BaCO3 + TiO2 + ZrO3 (nanopowder) deposited by the detonation method on metal substrates is investigated. The high radiation resistance of all types of coatings to the action of electrons with an energy of 30 keV and a fluence of up to 4 × 1016 cm-2 is established in measurements of the diffuse reflection spectra in vacuum at the place of irradiation (in situ). [ABSTRACT FROM AUTHOR]

The article focuses on the effects of strontium concentration on the properties of synthesized La(1-x)SrхMnO3 powders. Topics discussed include formation of La(1-x)SrхMnO3 and MnO3 during synthesis, calculation of absorption spectra in visible range and the power-law dependence of the absorption coefficient.