Volgograd State Technical University

Explosion welding of large-scale bimetallic plates remains a major unresolved challenge in the nuclear industry, petrochemical engineering, power generation, shipbuilding, and other sectors, mainly owing to the increased formation of melted regions and structural inhomogeneities that reduce joint strength. These issues are associated with cumulative and shock-wave processes occurring in the gap between the plates before collision. As the plate dimensions increase, both the exposure time of the plate surfaces to the high-temperature shock-compressed gas (SCG) formed in the gap and the amount of dispersed metal particles injected into the gap through cumulative effects become more significant, thereby affecting the SCG parameters. In this study, low-inertia thermoresistive sensors (RTDs) with high spatial resolution were used to measure high-intensity heat fluxes generated by the two-phase flow of gas saturated with dispersed metal particles during explosion welding of copper and steel plates under a wide range of conditions, including variations in plate dimensions and welding regimes (with and without cumulative jet formation). The results show that cumulative processes associated with the high-velocity flow of dispersed metal particles in the gap determine the nonuniform distribution of heat flux along the SCG region. Maximum values (up to 5 GW/m2) are reached near the collision point, the flux stabilizes at approximately 0.1 GW/m2 in the central region, and increases to approximately 0.7 GW/m2 at the shock-wave front. Despite the asymmetry of the cumulative particle flow across the gap height, the thermal effect of the SCG on the flyer and base plates was found to be the same. A twofold increase in plate length (from 0.28 to 0.55 m) leads to a fourfold increase in the heat flux in the central part of the SCG region (from 0.04 to 0.16 GW/m2). The novelty of this research lies in the fact that, for the first time, a dual influence of cumulative effects has been identified: the particles cool the SCG, reducing the heat flux compared to the regime without cumulative jet formation, while the additional momentum transfer from the particles to the gas accelerates the shock wave front (from 1.09 to 1.3–1.4 Vc) and prolongs the duration of thermal exposure.

The features of the microwave-assisted reaction of adamantan-2-one and camphor with aniline in the presence of anilinium chloride were studied. Formation of diphenylamine and products of its oxidative couplings was suppressed by performing the reaction under the inert atmosphere with microwave heating. Microwave irradiation accelerates the reaction rate by 1.5–2 times, increases the yield of the target products up to 60–78

Organic compounds have the widest practical application, and the methodology of their synthesis is often developed specifically to solve applied problems in medicinal chemistry, catalysis, materials chemistry, agriculture, food industry, and the creation of electronic and sensor devices. This is due to the huge variety of properties and functional capabilities of organic substances, as well as the ability to fine-tune their structure to impart certain practically useful characteristics. Currently, the number of organic compounds used in various fields of industry, medicine, and agriculture is in the hundreds of thousands, and their number continues to grow steadily due to the rapid development of synthetic organic chemistry and predictive methods for determining properties, including using artificial intelligence. This collective review is devoted to the achievements of Russian chemists in the field of practically oriented organic chemistry over the past 5–10 years. The review presents the achievements of leading research teams representing both RAS institutes and Russian universities, from Kaliningrad to Siberia.

Lipid membranes are often regarded as passive barriers, yet their nonlinear dielectric response remains poorly understood. Using all-atom molecular dynamics, we show that fully hydrated dipalmitoylphosphatidylcholine bilayers exhibit relaxor ferroelectric-like behavior under time-dependent electric fields. Unlike crystalline relaxors, which are bipolar and display little remanent polarization, lipid bilayers exhibit a unipolar polarization response: even an alternating current field produces persistent, asymmetric polarization. The underlying free-energy landscape contains two distinct minima, a nonpolarized state and a unipolarly polarized state, between which stochastic thermally activated transitions occur. Directionally resolved Van Hove analysis reveals pronounced anisotropy arising from out-of-plane electric dipole alignment, interleaflet coupling, and lateral polarization domains. Each field cycle nucleates polarization at distinct sites and monitors their relaxation, marking a crossover from thermal fluctuations to field-sustained polarization. Remarkably, these polarized domains persist after field removal, generating long-lived, spatially coherent dipolar patterns that encode nanoscale polarization memory. Potassium chloride amplifies these effects via dielectric screening and a modified hydration structure, enhancing electric dipole flexibility and cooperativity. Together, these results establish protein-free bilayers as nonlinear, history-dependent dielectrics capable of sustaining field-tunable electromechanical coupling, providing an emergent physical foundation for nanoscale information storage and memory phenomena reminiscent of short- and long-term plasticity in soft neuromorphic systems.

The specific features of the synthesis of 2,2-bis(4-aminophenyl)adamantane by the reaction of adamantan-2-one and aniline in an acidic medium were studied. The influence of the synthesis conditions on the composition of the reaction mixture, yield and purity of the final product was demonstrated. The reaction was found to proceed through the formation of intermediate products, 2-(4-aminophenyl)adamantan-2-ol and N-phenyladamantan-2-imine, with the highest yield of the target compound being 70