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Gd2(WO4)3 and Gd2(WO4)3:0.5% Tm3+, 10% Yb3+ nanopowders have been prepared by the Pechini method and solid-state sintering. According to X-ray diffraction results, the materials prepared by the Pechini method are more uniform in phase composition. Optimal synthesis conditions were defined: t = 900°C and τ = 1 h for Gd2(WO4)3 and t = 950°C and τ = 3 h for Gd2(WO4)3:0.5% Tm3+, 10% Yb3+. The surface morphology of the materials has been studied by scanning electron microscopy. The samples prepared by solid-state sintering have been found to be highly agglomerated, and large agglomerates have been shown to persist even after ultrasonic processing. The average size of the doped and undoped nanoparticles prepared by the Pechini method has been determined to be 44.0 and 47.6 nm, respectively. Luminescence spectra of Gd2(WO4)3:0.5% Tm3+, 10% Yb3+ were measured and compared the intensities of the Tm3+ 1G4 → 3H6, 1G4 → 3F4, 3F1,2→3H6, and 3H4 → 3H6 radiative transitions in the materials prepared by both methods. The data obtained in this study demonstrate that the Pechini process is a preferable and promising method for the synthesis of Gd2(WO4)3 and Gd2(WO4)3:Tm3+,Yb3+ nanopowders.

A study of the impact of service factors on Ti-6Al-4V alloy hydrogenation at temperatures close to climatic is performed on the example of a failed hydrogen compressor. It is established that under high gas pressure conditions and possible metal heating hydrogen saturation of Ti-6Al-4V alloy can reach significant values that surpass those acceptable by one to two orders of magnitude. Hydride phases are determined in the alloy by X-ray phase analysis. Temperature programmed desorption provides identification of phase transitions occurring during hydrogen evolution from the metal.

Research of hydrogen diffusion in VT6 alloy is carried out considering different types of heat treating and hydrogen charging. The influence of microalloying on the susceptibility to hydride formation and embrittlement of titanium alloys is analyzed, and also effects of an oxide film on hydrogen charging during heat treatment without protective atmosphere, are studied.

X-ray diffraction patterns of a photocurable epoxy acryl-based polymer composite with addition of ZnO nanocrystals are analyzed. We recover the size distribution function of the ZnO nanocrystals and estimate the median size of the nanocrystals (∼40–50 nm) from a detailed analysis of the most intensive peak in the X-ray diffraction pattern.

A comprehensive study (X-ray phase analysis, Raman spectroscopy, and IR reflectance measurements) of p-Sb2Te3 – xSex (0 ≤ x ≤ 0.10) crystals synthesized by the Czochralski method is carried out. The X-ray phase data and Raman spectra show that all of the alloy samples under study are rhombohedral crystals in structure, with unit-cell parameters close to those of Sb2Te3 crystals. At the same time, the formation of regions with different degrees of the replacement of Te atoms with Se atoms is observed. The reflectance spectra of the crystals, R(ν), have a characteristic minimum at about 1000 cm–1. The minimum is attributed to hole plasma vibrations. The plasma minimum systematically shifts to higher frequencies, as the Se content is increased. Calculation of the reflectance spectra in the context of the Drude–Lorentz model satisfactorily describes the experimental data; in this case, it is necessary to take into account also the contribution of optical crystal-lattice vibrations to spectra in the low-frequency region. The calculation makes it possible to determine the optical parameters of the crystals and to estimate the hole effective mass and the optical conductivity.

In this work a technique for optically active nanocomposite structures consisting of an oxide matrix with plasmonic NPs were demonstrated. A nanocomposite film was formed on a silicon substrate by NiO oxide matrix sputtering and gold nanoparticles dewetting. Studies of the morphology, elemental composition, and structure of the nanocomposite using SEM, EDS, XRD methods are presented. The transfer of the film onto a polymer substrate made it possible to study the optical characteristics of the obtained structures. It is shown that formed nanocomposite coatings on a polymer substrate are highly flexible and exhibit excellent mechanical properties.

Effect of ozone and water vapor on the chemical deposition of TiO2 from the gas phase in the system of titanium tetraisopropylate-oxygen was examined. Introduction of ozone in the reaction medium was shown to result in the precipitation of smooth TiO2 layers at 240°C, and the addition of water vapor leads to the formation with higher rate of unconsolidated layers. Adding ozone to the reaction medium with low moisture content (up to 0.65 Pa) allows obtaining at temperatures 250–350°C with high rate of growth the TiO2 layers with the anatase nanocrystals of high photocatalytic activity.

The effect of heat treatment on the physicochemical and technological properties of aluminum-based powder materials containing rare-earth elements is investigated. Powder composites are produced by mechanical alloying in ball mills. Recommendations for molding and heat treatment conditions are given.

The possibility of obtaining nickel hydroxide from solutions produced in ammonia leaching of the active paste of positive electrodes of a nickel-iron battery was studied.

It is experimentally demonstrated that incorporated copper atoms change the electron density and, hence, modify the structure of graphite crystal planes. Using the proposed method, it is possible to calculate the function describing structural distortions and to determine the displacements of atoms in the distorted crystal planes.