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Structure and properties of detonation gun sprayed (DS) coatings from the synthesized FeAlSi/Al2O3 powder have been investigated. The powder was manufactured through a mechanically assisted self-propagating high-temperature synthesis route. A small addition of nanosized SiO2 particles to the reaction mixture for the synthesis of FeAl-FeAl2 eutectoid refines the thickness of B2-FeAl lamellar grains in the synthesized powder. Silicon arisen from the aluminothermic reduction of SiO2 during the synthesis is preferentially located in the B2-phase. High-quality coatings with porosity less than 1 vol% and nanocomposite structure have been obtained from the synthesized powder using a computer-aided ‘Perun-S’ detonation gun complex. Phase composition of the coatings includes B2-FeAl, hercinite FeAl2O4, FeAl2, A2-Fe-based solid-solution, Al2O3, and probably complex Fe2.95Si0.05O4 oxide. It is formation of nanocomposite structure with the mean crystallite size of main components in the range of ≈9–15 nm that seems to be responsible for the lower microhardness of the coatings from the FeAlSi/Al2O3 powder than that of the basic Fe-Al eutectoid composition. As-sprayed coatings from the synthesized FeAlSi/Al2O3 powder demonstrate good room and elevated temperature erosion behavior. Oxide dominated erosion with mixed brittle-ductile wear behavior is thought to occur in the coatings at 550 °C. The proposed powder modification is found to be beneficial for the oxidation resistance of DS coatings in air at 950 °C. Promoting of alumina formation during oxidation and the corresponding decline in Fe2O3 content in the oxide scale are considered as the main reasons for the slower oxidation kinetics of the FeAlSi/Al2O3 coatings as compared with those of the basic Fe-Al eutectoid composition.

The GdTi0.05Fe0.95-xMnxSi, х = 0–0.95 intermetallic compounds with a tetragonal crystal structure of the CeFeSi type (space group P4/nmm, N 129, tP6) have been studied. The lattice parameter c and the Curie temperature TC increase quickly, whereas the lattice parameter a is almost unchanged in the system when the content of Mn increases. The saturation magnetization, magnetocaloric effect MCE and refrigerant capacity RC change non-monotonically with a dip at intermediate compositions that is presumably due to the canted ferrimagnetic structure of these compounds. The MCE and RC vary in a field changing to 17 kOe within the small ranges of 1.6–2.7 J/kgK and 60–117 J/kg around TC, respectively, while TC changes in a wide range around the room temperature from 160 to 360 K.

The presence of carotenoids in the vitreous body, retina, lens, retinal pigment epithelium together with choroid (hereinafter RPE), and ciliary body and iris together with choroidal stroma (hereinafter CBI) was studied throughout the second trimester of prenatal development of the human eye. It has been found that the vitreous body, retina, and RPE contain lutein and its oxidized forms. Zeaxanthin was not found in the tissues studied. The presence of lutein in the vitreous body is transient and no longer detected after 28 weeks of gestation. Lutein was not detected in the lens and CBI, but its oxidized forms were found. The presence of carotenoids in different tissues of the eye in the course of normal eye development and the antioxidant role of carotenoids are discussed.

The GdFe1-xTixSi (x = 0–0.2) intermetallic compounds have been studied. They crystallize into the tetragonal CeFeSi (P4/nmm)–type structure. With increasing Ti content, the Curie temperature TC and the lattice parameter c increase quickly for x = 0–0.1 and then, more moderate because of the solubility limit, whereas the saturation magnetization at 4 K and the lattice parameter a remain almost unchanged. The theoretical DFT + U calculations showed that the growth of Ti content affects the electronic structure of GdFe1-xTixSi by significantly increasing the density of electron states at the Fermi level N(EF). At the same time, the total magnetic moment does not change because both Fe and Ti are non-magnetic in these intermetallic compounds. The growth of the density of electron states near the Fermi level is accompanied by the rapid growth of TC in the GdFe1-xTixSi system.

Using synchrotron-based in situ X-ray diffraction, the structural changes of LiCoO 2 , LiCo 0.5 Ni 0.5 O 2 , and LiNi 0.65 Co 0.25 Mg 0.05 Ti 0.05 O 2 cathode materials during charge in the voltage range of 3.5 to 5.2 V have been studied. When a LiCoO 2 cathode was charged above 4.5 V, a new intermediate phase O1a was observed, before the terminal phase O1 was formed around 4.8 V. In the X-ray diffraction spectra for LiCo 0.5 Ni 0.5 O 2 and LiNi 0.65 Co 0.25 Mg 0.05 Ti 0.05 O 2 cathode materials, Bragg peaks representing the O1 structure were also observed. The amounts of O1 structure formed at the end of charge (5.2 V for LiNi 0.65 Co 0.25 Mg 0.05 Ti 0.05 O 2 and 5.0 V for LiCo 0.5 Ni 0.5 O 2 ) were increased with increasing Co content.