This paper presents the results of experimental studies of the interaction of helium plasma with a near-surface tungsten carbide layer. The experiments were implemented at the plasma-beam installation. The helium plasma loading conditions were close to those expected in the ITER divertor. The technology of the plasma irradiation was applied in a stationary type linear accelerator. The impact of the helium plasma was realized in the course of the experiment with the temperatures of ~905 °C and ~1750 °C, which were calculated by simulating heat loading on a tungsten monoblock of the ITER divertor under the plasma irradiation at the load of 10 MW/m² and 20 MW/m², respectively. The structure was investigated with scanning microscopy, transmitting electron microscopy and X-ray analysis. The data were obtained showing that the surface morphology changed due to the erosion. It was found that the carbidization extremely impacted the plasma–tungsten interaction, as the plasma–tungsten interaction with the carbide layer led to the carbon sputtering and partial diffusion towards to the depth of the sample. According to these results, WC-based tungsten carbide is less protected against fracture by helium than W and W₂C. An increase in temperature leads to much more extensive surface damage accompanied by the formation of molten and recrystallized flanges.

Hydrogen is widely regarded as a key energy carrier of the future; however, its efficient and safe storage remains one of the central scientific and technological challenges. This article systematizes contemporary approaches to hydrogen storage, with a particular emphasis on solid-state materials as the most promising direction. The main storage technologies—compressed, liquid, and solid hydrogen—are reviewed, and there is an analysis of their advantages and limitations. Special attention is given to the fundamental aspects of solid-state hydrogen storage, including the thermodynamics and kinetics of hydrogen absorption and desorption processes. A comparative analysis of various material classes is presented, including intermetallic metal hydrides based on AB₅-type and AB₂-type compositions, magnesium-based systems, palladium-modified structures, as well as complex hydrides (alanates, borohydrides, and amide–imide systems).The role of nanostructuring and carbon-based nanomaterials in enhancing storage capacity and improving kinetics is also examined. Key challenges are discussed, including high desorption temperatures, slow kinetics, and material degradation. Modern strategies for performance enhancement, such as catalytic activation, alloying, and nanostructuring, are highlighted.

During the operation of the first core of the IGR pulsed graphite reactor (1961–1966), 2.6 tonnes of irradiated highly enriched uranium (HEU)–graphite fuel were accumulated. For its immobilization, cementation with preliminary down-blending using depleted uranium was proposed, with the ²³⁵U concentration in the final matrix limited to less than 50 ppm. Among the radionuclides accumulated in irradiated uranium–graphite fuel, ¹³⁷Cs is of particular concern because it is a long-lived uranium fission product with high mobility in cementitious systems. In this study, four cement compositions with water-to-binder ratios of 0.38–0.42 and Portland-cement-to-fly-ash ratios of 1:2.5 and 1:1.77 were investigated for the immobilization of irradiated uranium–graphite fuel. The ¹³⁷Cs activity in the cement samples was determined using the substitution method with a point calibration gamma source and the MCNP5 code to calculate correction factors accounting for the measurement geometry and gamma-ray self-absorption. For all compositions, the initial ¹³⁷Cs leaching rates exceeded 1 × 10⁻³ g/(cm²·day) during the first 1–3 days of testing; however, from day 7 onward, the leaching rates decreased below the regulatory limit and continued to decline during the subsequent test period. Based on these results, as well as on the leachability of calcium and silicon dioxide, two candidate cement–matrix compositions were selected. The results provide an experimental basis for further scale-up studies aimed at the immobilization of irradiated HEU graphite fuel from the IGR reactor.

A method for physical modeling of the influence of bulk leakage-current channels (dislocations) on the electrophysical and lighting characteristics of LEDs by connecting the p–n junction of an LED in parallel to an ohmic resistance or another p–n junction is described. The relationships that allow one to determine the change in the electrophysical and lighting characteristics of LEDs under the influence of various external factors (ionizing radiation, long-term operation, etc.) have been established. Using the obtained relationships, it is possible to determine the electrophysical characteristics of dislocations according to the changes in the electrophysical and lighting characteristics of LEDs, taking the role of dislocations into account. Based on the literature data, the efficiency of using the established relationships in the analysis of the characteristics of LEDs that are exposed to external impacts has been shown.

This paper presents the results of experiments to produce hydrogen using methane pyrolysis with microwave (MW) discharge and steel catalyst in an applied research installation PM-6. The experiments were conducted to determine the fullest extent of methane decomposition in microwave discharge in the PM-6 installation us- ing steel catalyst with varied nickel content. The results showed that the use of nickel catalysts provides the highest hydrogen yield under optimal conditions. Hydrogen production technology was implemented using catalyst in MW discharge with the maximum rate of methane conversion up to 32±2 % and hydrogen selec- tivity up to 85±1 % at MW discharge of 0.6 kW, methane flow rate of 0.25±0.05 l/min and argon 8.0±0.2 l/min. Overall, the results of the study highlight the importance of choosing catalysts to achieve op- timal conditions for methane pyrolysis and create efficient technologies for hydrogen production. The data obtained from the experiments could be useful for the development of industrial pyrolysis plants, which will contribute to a more sustainable energy future and a reduced carbon footprint.

A classification of the radiation power losses of the LED active layer is proposed based on the analysis of the known literature data and the structure of structurally designed LEDs. Active and passive power losses are distinguished. Passive radiation power losses do not affect changes in the quantum yield of the active (working) layer of an LED and/or the forward branch of the volt–ampere characteristic, but they can be detected as anomalies in the LED lighting characteristics. A method for determining the passive power losses of radiation from the active layer of LEDs is proposed. Using the example of IR LEDs fabricated on the basis of AlGaAs heterostructures, the effectiveness of controlling passive losses of the LED emission power in the study of their operational properties is shown.