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The diagnosis of faults in induction motors, such as broken rotor bars, is critical for preventing costly emergency shutdowns and production losses. The complexity of this task lies in the diversity of induction motor operating regimes. Specifically, a change in load alters the signal’s frequency composition and, consequently, the values of fault diagnostic features. Developing a reliable diagnostic model requires data covering the entire range of motor loads, but the volume of available experimental data is often limited. This work investigates a data augmentation method based on the physical relationship between the frequency content of diagnostic signals and the motor’s operating regime. The method enables stretching and compression of the signal in the spectral domain while preserving Fourier transform symmetry and energy consistency, facilitating the generation of synthetic data for various load regimes. We evaluated the method on experimental data from a 0.37 kW induction motor with broken rotor bars. The synthetic data were used to train three diagnostic models: a Multilayer Perceptron (MLP), a Convolutional Neural Network (CNN), and a hybrid CNN-MLP model. Results indicate that the proposed augmentation method enhances classification quality across different load levels. The hybrid CNN-MLP model achieved the best performance, with an F1-score of 0.98 when augmentation was employed. These findings demonstrate the practical efficacy of physics-guided spectral augmentation for induction motor fault diagnosis.

The growing demand for cheap, safe, recyclable, and environmentally friendly batteries highlights the importance of the development of organic electrode materials. Here, we present a novel redox-active polymer comprising a polyaniline-type conjugated backbone and quinizarin and anthraquinone units. The synthesized polymer was explored as a cathode material for batteries, and it delivered promising performance characteristics in both lithium and potassium cells. Excellent lithiation efficiency enabled high discharge capacity values of >400 mA g−1 in combination with good stability upon charge–discharge cycling. Similarly, the potassium cells with the polymer-based cathodes demonstrated a high discharge capacity of >200 mAh g−1 at 50 mA g−1 and impressive stability: no capacity deterioration was observed for over 3000 cycles at 11 A g−1, which was among the best results reported for K ion battery cathodes to date. The synthetic availability and low projected cost of the designed material paves a way to its practical implementation in scalable and inexpensive organic batteries, which are emerging as a sustainable energy storage technology.

Despite extensive research in the field of thrombotic diseases, the prevention of blood clots remains an important area of study. Therefore, the development of new anticoagulant drugs with better therapeutic profiles and fewer side effects to combat thrombus formation is still needed. Herein, we report the synthesis and evaluation of novel pyrroloquinolinedione-based rhodanine derivatives, which were chosen from 24 developed derivatives by docking as potential molecules to inhibit the clotting factors Xa and XIa. For the synthesis of new hybrid derivatives of pyrrolo[3,2,1-ij]quinoline-2-one, we used a convenient structural modification of the tetrahydroquinoline fragment by varying the substituents in positions 2, 4, and 6. In addition, the design of target molecules was achieved by alkylating the amino group of the rhodanine fragment with propargyl bromide or by replacing the rhodanine fragment with 2-thioxoimidazolidin-4-one. The in vitro testing showed that eight derivatives are capable of inhibiting both coagulation factors, two compounds are selective inhibitors of factor Xa, and two compounds are selective inhibitors of factor XIa. Overall, these data indicate the potential anticoagulant activity of these molecules through the inhibition of the coagulation factors Xa and XIa.

In this article, the specific features of competitive ionic and molecular transport in nanocomposite systems based on network membranes synthesized by radical polymerization of polyethylene glycol diacrylate in the presence of LiBF4, 1-ethyl-3-methylimidazolium tetrafluoroborate, ethylene carbonate (EC), and TiO2 nanopowder (d~21 nm) were studied for 1H, 7Li, 11B, 13C, and 19F nuclei using NMR. The membranes obtained were studied through electrochemical impedance, IR-Fourier spectroscopy, DSC, and TGA. The ionic conductivity of the membranes was up to 4.8 m Scm−1 at room temperature. The operating temperature range was from −40 to 100 °C. Two types of molecular and ionic transport (fast and slow) have been detected by pulsed field gradient NMR. From quantum chemical modeling, it follows that the difficulty of lithium transport is due to the strong chemisorption of BF4– anions with counterions on the surface of TiO2 nanoparticles. The theoretical conclusion about the need to increase the proportion of EC in order to reduce the influence of this effect was confirmed by an experimental study of a system with 4 moles of EC. It has been shown that this approach leads to an increase in lithium conductivity in an ionic liquid medium, which is important for the development of thermostable nanocomposite electrolytes for Li//LiFePO4 batteries with a base of lithium salts and aprotonic imidasolium ionic liquid.

Elementary processes of electro mass transfer in the nanocomposite polymer electrolyte system by pulse field gradient, spin echo NMR spectroscopy and the high-resolution NMR method together with electrochemical impedance spectroscopy are examined. The new nanocomposite polymer gel electrolytes consisted of polyethylene glycol diacrylate (PEGDA), salt LiBF4 and 1—ethyl—3—methylimidazolium tetrafluoroborate (EMIBF4) and SiO2 nanoparticles. Kinetics of the PEGDA matrix formation was studied by isothermal calorimetry. The flexible polymer–ionic liquid films were studied by IRFT spectroscopy, differential scanning calorimetry and temperature gravimetric analysis. The total conductivity in these systems was about 10−4 S cm−1 (−40 °C), 10−3 S cm−1 (25 °C) and 10−2 S cm−1 (100 °C). The method of quantum-chemical modeling of the interaction of SiO2 nanoparticles with ions showed the advantage of the mixed adsorption process, in which a negatively charged surface layer is formed from Li+ BF4— ions on silicon dioxide particles and then from ions of the ionic liquid EMI+ BF4−. These electrolytes are promising for use both in lithium power sources and in supercapacitors. The paper shows preliminary tests of a lithium cell with an organic electrode based on a pentaazapentacene derivative for 110 charge–discharge cycles.

Analysis of angular dependences of the diffraction peak broadening observed in α-uranium in as-received state, after loading by converging spherical shock wave, low-speed uniaxial deformation, and annealing at 850°С has been presented in this work. Broadening anisotropy identical for all the states investigated has been demonstrated. The authors have attempted to explain the phenomena by Young’s modulus anisotropy of uranium or the crystallite orientation relative to the load applied under plastic deformation.

The effect of the composition of liquid electrolytes in the bulk and at the interface with the LiFePO4 cathode on the operation of a solid-state lithium battery with a nanocomposite polymer gel electrolyte based on polyethylene glycol diacrylate and SiO2 was studied. The self-diffusion coefficients on the 7Li, 1H, and 19F nuclei in electrolytes based on LiBF4 and LiTFSI salts in solvents (gamma-butyrolactone, dioxolane, dimethoxyethane) were measured by nuclear magnetic resonance (NMR) with a magnetic field gradient. Four compositions of the complex electrolyte system were studied by high-resolution NMR. The experimentally obtained 1H chemical shifts are compared with those theoretically calculated by quantum chemical modeling. This made it possible to suggest the solvate shell compositions that facilitate the rapid transfer of the Li+ cation at the nanocomposite electrolyte/LiFePO4 interface and ensure the stable operation of a solid-state lithium battery.

The influenza virus genome features a very high mutation rate leading to the rapid selection of drug-resistant strains. Due to the emergence of drug-resistant strains, there is a need for the further development of new potent antivirals against influenza with a broad activity spectrum. Thus, the search for a novel, effective broad-spectrum antiviral agent is a top priority of medical science and healthcare systems. In this paper, derivatives based on fullerenes with broad virus inhibiting activities in vitro against a panel of influenza viruses were described. The antiviral properties of water-soluble fullerene derivatives were studied. It was demonstrated that the library of compounds based on fullerenes has cytoprotective activity. Maximum virus-inhibiting activity and minimum toxicity were found with compound 2, containing residues of salts of 2-amino-3-cyclopropylpropanoic acid (CC50 > 300 µg/mL, IC50 = 4.73 µg/mL, SI = 64). This study represents the initial stage in a study of fullerenes as anti-influenza drugs. The results of the study lead us conclude that five leading compounds (1–5) have pharmacological prospects.

The article considers the effect of the solvate environment of the lithium cation in various aprotic solvents.The redox reactions of electrodes made from a polymeric condensation product of triquinoyl with 1,2,4,5-tetraaminobenzene are studied. A 1 M LiPF6 solution was used as an electrolyte, in either ethylene carbonate/dimethyl carbonate (EC/DMC) or tetraglyme. Based on the electrochemical studies and quantum chemical modeling, it was shown that the desolvation of lithium cations in the tetraglyme-based electrolyte makes it possible to obtain a capacity close to the theoretical one (up to 546 mAh g−1) and only 125 mAh g−1 for the EC/DMC electrolyte. This decrease is due to the fact that the lithium cation adds to the functional groups of the organic material with two dimethyl carbonate molecules, as well as the PF6− anion.

Graebe–Ullmann reaction was used to synthesize 3-aryl(methyl)-1-methyl(cyclopropyl)-4-nitro-5Н-pyrido[4,3-b]indoles containing substituents in the pyridine ring. A new scheme was developed for the synthesis of the starting 1-[6-aryl(methyl)-2-methyl(cyclopropyl)- 3-nitropyridin-4-yl]-1Н-1,2,3-benzotriazoles: 1) ammonolysis of 3-nitroisonicotinic acid ethyl esters, 2) a modified Hofmann reaction of 3-nitroisonicotinamides, 3) cleavage of ethyl (2-aryl-3-nitropyridin-4-yl)carbamates, 4) synthesis of 4-chloro-3-nitropyridines by diazotation reaction of 4-amino-3-nitropyridines, followed by nucleophilic substitution of diazo group in 4-pyridyldiazonium salts with a chlorine atom.