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On the occasion of the 130th anniversary of the outstanding Russian scientist Nikolai Nikolaevich Semenov, the winner of the Nobel Prize in Chemistry in 1956, the main milestones of his biography are described and the main scientific achievements are shown. N.N. Semenov is the discoverer of chain reactions in chemistry, the creator of the theory of chain processes, the theory of branched chain reactions, and the law of the increase in the concentration of active centers over time. From 1931, N.N. Semenov created and continuously led the Institute of Chemical Physics for 55 years; now the institute bears his name. The research and administration work of N.N. Semenov and his personal qualities are described. The paper presents materials about N. N. Semenov preserved at the International Nobel Information Center, which has been honoring the scientist&#39s memory for half a century. It also provides detailed information about Semenov&#39s nomination for the Nobel Prize in Chemistry, as well as the people he himself nominated for the award.

The phase evolution in the joint zone of the 08Cr18Ni10Ti–AlMg6 bimetal obtained by explosive welding followed by isothermal annealing at 500–550 C was investigated using the method of layer-by-layer XRD analysis. It was established that after explosive welding, a metastable quasicrystalline phase, Al86Fe14, forms in the near-surface layers. This phase decomposes during isothermal annealing, leading to the formation of equilibrium intermetallic compounds Al5Fe2 and Al13Fe4. Additionally, after annealing, the formation of a ternary phase, Cr2Mg3Al18, is detected, indicating the activation of diffusion interaction between the components of the steel and the aluminium alloy. Thus, a sequential evolution of the phase composition in the joint zone after explosive welding and thermal exposure is demonstrated. The results obtained expand the understanding of the mechanisms of phase formation and diffusion processes at the joint interface in the 08Cr18Ni10Ti–AlMg6 bimetal during explosive welding, as well as the influence of thermal exposure on phase evolution.

The influence of graphene oxide (GO) additives on the structure of the graphite/hexagonal boron nitride hybrid filler and the tribotechnical characteristics of anti-friction composites obtained on its basis was assessed. The nanocomposite preparation method included obtaining the filler (mixture) through mechanical activation of the components, hot mixing the mixture with high-temperature coal tar pitch, pressing, and high-temperature firing. To ensure hermetic sealing, the products were finally impregnated with a furfuryl alcohol solution, followed by polymerization at 300C. Mixture samples were analysed using thermogravimetry and X-ray diffraction analysis. It was found that with an increase in GO content to 2.80 wt.%, the thermal stability of the mixture increased, after which it began to decline. The dependence of the crystal structure parameters of the filler components (Lc and N) on the GO concentration also exhibited an extreme behaviour. A sample of the charge containing 1.64 wt. % graphene oxide is characterized by maximum Lc and N values for boron nitride and minimum values for the graphite component. Furthermore, the filler of this composition demonstrates maximum sorption capacity for pitch, which contributes to the formation of a high-density and durable material. The finished nanocomposite demonstrates gas permeability of less than 1?10(–5) cm2 *s–1 and compressive strength equal to 197.5 MPa, which is 1.5 times higher than that of an analogue (NIGRAN-V). Bench tests showed that due to the introduction of graphene oxide into the filler composition, wear intensity is reduced by 16 times compared to a sample based on an unmodified charge. The nanocomposite of the optimal composition remains hermetically sealed under extreme operating conditions and can serve as the basis for the creation of high-density and ultra-strong anti-friction materials suitable for use in sealed friction units of pump and compressor systems.

The paper investigated the regularities of mechanochemical formation of niobium silicides utilizing industrial waste (niobium turnings and silicon wafers) as feedstock. The influence of the milling ball diameter and the duration of mechanical activation on the mass fraction of formed niobium silicides was identified. X-ray phase analysis and scanning electron microscopy methods revealed that morphological changes are closely related to the formation of new phases such as NbSi2, Nb5Si3, Nb3Si. A high degree of comminution and particle deformation is required for successful mechanochemical synthesis, with activation time being a key factor. Maximum structural disordering and refinement are achieved in intermediate activation regimes (10–15 min). The use of larger balls (8 mm) intensifies deformation and disordering processes, leading to a sharper increase in microstrain and faster formation of nanoscale silicides. The total mass fraction of niobium silicides reached 46 wt. % when using 8 mm balls, compared to 38 wt. % when using 5 mm balls after 30 minutes of MA. The utilization of secondary waste as raw materials is suitable for niobium silicide production.

A series of ferrocene-containing ionic liquids (Fc-ILs) (bis(trifluoromethylsulfonyl)imides ofN-methyl-N- (ferrocenylmethyl)pyrrolidinium, N-methyl-N-(ferrocenylmethyl)piperidinium and N-ethyl-N-(ferrocenylmethyl) pyrrolidinium) were tested as redox-active additives for supercapacitor (SC)ionic liquid electrolytes. Undoped and nitrogen-dopedgraphene nanoflakes (GNFs) were used as an electrode material. The electrochemical characteristics of SCs were analyzed bycyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy. Self-discharge of SCs was measured at open-circuit potential. The specific capacitance, energy density, Coulombic efficiency and self-discharge of the SCs depended on the textural parameters of the electrode material and type and content of the additive to the electrolyte. The increase in the Fc-IL fraction in the 0.5 M [EMIm][NTf2]/ acetonitrile supporting electrolyte enhanced the specific capacitance of the GNF-based electrode from 85 to 126 F·g?1 at a scan rate of 5 mV·s?1 due to additional pseudocapacitive contribution from reversible electron transfer in Fe2+/Fe3+. Moreover, the redox-active additives provided the increase in energy density of the SC up to 21.7 Wh·kg?1 . Nitrogen doping of GNF accelerated the self-discharge due to the interaction between redox-active species and nitrogen groups on the electrode surface.

Intermediates to produce ceramic powders were synthesized using amorphous potassium polytitanate (K2O*4TiO2*xH2O, PPT) modified in aqueous solutions of mixtures of manganese and aluminum sulfates, taken in a 2 : 1 molar ratio, and manganese, aluminum, and chromium sulfates, taken in a 2 : 1/2 : 1/2 molar ratio. It was shown that heat treatment of these intermediates enables the synthesis of single-phase powders of hollandite-like solid solutions K1.70Mn1.66Al0.81Ti5.52O16 and K1.76Mn1.60Al0.39Сr0.45Ti5.48O16, respectively. Ceramic dielectrics were fabricated using compacted powders of the obtained products, which were sintered at 1080 C/3 h. The electrical properties of the ceramic specimens produced were investigated by impedance spectroscopy methods. It was shown that partial replacement of Al with Cr in the intermediate composition increases the permittivity (from 820 to 1580) and reduces dielectric loss (tg(), from 0.89 to 0.22). Moreover, some justified doping additives (Nb2O5, 0.5 %; Nd2O3, 0.3 %; LiF, 0.8 %) and a flux (zinc borate, 2%) allow for a further increase in dielectric constant (up to 57,800 +/- 600), decrease of tg() (down to 0.084 +/- 0.02) and significantly increase the temperature stability of permittivity for the obtained ceramics in the temperature range from –55 to +125 C up to the level corresponding to a X7T category of dielectrics.

Biochar samples from crustacean processing waste were synthesized by carbonization followed by alkaline activation. The influence of synthesis parameters (time, temperature) on the porous structure of biochar was considered. The results showed that biomass carbonization conditions significantly affect the final porosity parameters. It was found that the biochar samples obtained by varying the synthesis parameters were micromesoporous. Temperature was shown to be the main influencing factor during biomass carbonization. At a three-hour carbonization duration and a temperature of 650 C, the specific surface area (2708 m2*g –1) and pore volume (total pore – 1.58 cm *g –1, micropore – 0.64 cm3 *g –1, mesopore – 0.94 cm3*g –1) in the obtained biochar reached their maximum values. Methane adsorption on the obtained biochar was studied at ambient temperature and pressure up to 100 bar. Biochar obtained from crustacean waste was shown to exhibit a high methane adsorption capacity of ~18 mmol*g –1. Experimental adsorption data were analyzed using the Langmuir, Freundlich, and Dubinin-Radushkevich models. The influence of synthesis parameters on the pore structure of biochars, as well as the adsorption data evaluated in the study, are useful for designing adsorption systems.

This review summarizes the results of using detonation nanodiamonds (DNDs) over the past 10 years in emerging areas of science and technology. Oriented coalescence of nanodiamond crystallites (~ 4 nm) under high temperature and pressure leads to the formation of single crystals with multi-micron dimensions. New magnetic resonance imaging contrast agents have been proposed and studied in the form of aqueous suspensions containing DNDs doped with manganese and gadolinium ions. The potential use of DND crystallites as reflectors for very slow neutrons (~ 50 m*s –1) has been demonstrated. The feasibility of producing diamond coatings containing europium ions by the CVD-method has been shown. An electrorheological effect was observed when an electric field is applied to suspensions of nanodiamond crystallites in oils, with DND crystallites acting as nodes in a fractal conductive network. Mixing DNDs with tungsten (W) powder followed by sintering increases the Young&#39s modulus of sintered tungsten by a factor of four and its hardness by 1.5–2.0 times. Replacing standard DNDs (derived from TNT/RDX mixtures) with boron-doped DNDs produced during detonation synthesis further increases the microhardness of sintered tungsten by up to four times. New types of pseud alloys were obtained for the first time: an aluminum-tungsten alloy containing 10 wt. % tungsten and 90 wt. % aluminum with a hardness of HB 60, and an aluminum-copper-tungsten alloy containing 15 wt. % Al, 50 wt. % Cu, 35 wt. % W, and 1.2 wt. % DNDs. The resulting compositions are readily machinable. The use of aqueous nanodiamond suspensions in photonics has been demonstrated for producing linear optical filters resistant to high-power radiation. Application of an intermediate product from DND synthesis – diamond charge – increased the germination rate of Chinese cabbage seeds by 70 % compared to normal rates. Adding diamond charge to space-grade lubricants reduced component wear by a factor of two. Modification of paste-like fuels with nanodiamonds increased their burning rate by up to 23%.

This article presents a review of contemporary studies on the production of composite materials based on polymethyl methacrylate (PMMA) and polypropylene (PP) with improved properties. The formation of a coherent scientific understanding of the processes involved in producing nanocomposites underpins the development of nextgeneration materials. In such systems, conventional polymers serve as the matrix, while carbon nanotubes act as the conductive filler. The study of effects that arise from the introduction of ultra-small quantities of carbon nanoparticles is of key importance here: it is precisely these effects that enable a dramatic change in a wide range of polymer properties without significantly increasing material costs. Alongside experiments aimed at improving conductive polymers, multiscale modeling is playing an increasingly priority role. Computational experiments reduce development costs and predict the stability of materials under load, transforming modeling into a key driver of technological progress in the field of organic electronics. Confirming the effectiveness of computational methods, the authors of this article present the findings of their own research on the interaction mechanisms between the aforementioned polymers and single- and double-walled carbon nanotubes, which led to the creation of a composite polymer system. This research was conducted using a modern quantum-chemical method – density functional theory (DFT). Thus, the presented review not only summarizes existing achievements in the field of CNT/PMMA and CNT/PP composites, but also establishes a new methodological vector in which computational methods (particularly DFT) become an equal and, at early stages, a priority tool for designing nanocomposites with predictable properties.