Abstract: The paper studied the effect of high-voltage short-pulse electrohydraulic discharge (HVSPED) on the processes of catalytic cracking of oil sludge in order to increase the yield of light hydrocarbon fractions. A set of laboratory experiments was carried out with varying the key parameters of HVSPED - voltage, pulse frequency and exposure time. A nanocomposite bentonite catalyst impregnated with nickel was used. The optimal electrophysical parameters of oil-sludge treatment by HVSPED were determined, providing the maximum yield of gasoline and kerosene fractions. The effectiveness of HVSPED treatment of oil sludge in the presence of a catalyst was confirmed by DTA–thermogravimetric analysis and chromatographic-mass spectral analysis of the light and middle fractions of the hydrogenate. The proposed approach made it possible to enhance the resource and energy efficiency of oil-sludge processing using HVSPED, demonstrating high potential for further industrial application.

Abstract: We present a methodology that enhances the analytical performance of organic electrochemical transistors (OECTs) by continuously cycling the devices through gate-potential sweeps during sensing experiments. This continuous cycling method (CCM) enables real-time acquisition of full transfer curves, allowing simultaneous monitoring of multiple characteristic parameters. We show that the simultaneous temporal evolution of several OECT response parameters (VTH, VG,gmax, and gmax) provides highly sensitive descriptors for detecting pH changes and macromolecule adsorption on OECTs based on PANI and PEDOT channels. Moreover, the method allows reconstruction of IDS–time profiles at any selected gate potential, enabling the identification of optimal VG values for maximizing sensitivity. This represents a substantial improvement over traditional measurements at fixed VG, which may suffer from reduced sensitivity and parasitic reactions associated with gate polarization. Moreover, the expanded set of parameters obtained with the CCM provides deeper insight into the physicochemical processes occurring at both gate and channel electrodes. We demonstrate its applicability to monitoring polyelectrolyte and enzyme adsorption as well as detecting urea and glucose through enzyme-mediated reactions. Owing to its versatility and the richness of the information it provides, the CCM constitutes a significant advance for the development and optimization of OECT-based sensing platforms.

Abstract: This study examines the effects of hydrothermal and oleothermal treatments on the physical, mechanical, and colorimetric properties of Dabema wood. Samples were heated at 100, 160, and 220 °C for 2, 3.5, and 5 hours under both processing conditions. The physical properties changed markedly after treatment. The equilibrium moisture content decreased from 13.16% in the untreated wood to 7.50% after hydrothermal treatment at 160 °C for 5 hours, and to 4.80% after oleothermal treatment at 220 °C for 5 hours. Water absorption declined from 78% to 39% and then to 17%. Hydrothermal treatment darkened the wood, whereas oleothermal treatment preserved a lighter color. Mechanical performance improved. The modulus of elasticity (MOE) in compression increased from 33332.76 MPa to 70836.53 MPa after oleothermal treatment at 220 °C for 5 hours. Flexural strength reached 56 to 58 MPa. In tension, the MOE increased from 4271 MPa to 5527 MPa, and the maximum tensile strength reached 88 MPa. PCA and RSM analyses indicate that oleothermal treatment at 160 °C for 3.5 to 5 hours offers the most effective conditions for enhancing stiffness while controlling color variation. Thermogravimetric analyses (TG/DTG) show that hydrothermal treatment promotes hemicellulose degradation, whereas oleothermal treatment stabilizes the cellulose–lignin network. Overall, hydrothermal treatment improves dimensional stability, while oleothermal treatment provides an optimal balance between stiffness and color stability. Deep color differences arise from furanic resin formation in hydrothermal treatment, suppressed by oil in oleothermal processing.

Abstract: The formation of interfacial charge transfer (ICT) complexes between phenolic ligands and metal oxide surfaces enables surface functionalization strategies with potential applications in catalysis and bioconjugation. In this study, magnetite (Fe₃O₄) nanoparticles were modified with two phenolic ligands, 5-aminosalicylic acid (5ASA) and caffeic acid (CA), to generate ICT complexes capable of covalent or non-covalent enzyme immobilization, respectively. The modified nanomaterials were structurally characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR). Horseradish peroxidase (HRP) was immobilized on these functionalized supports. Catalytic activity was evaluated using pyrogallol oxidation assays, with systematic variations in nanoparticle mass and enzyme concentration. The Fe₃O₄/5ASA–HRP system exhibited a maximum activity of 2.5 U per 20 mg of support (approximately 125 U/g), whereas Fe₃O₄/CA showed minimal activity under the same conditions. Data from enzyme loading studies confirmed that 5ASA-enabled covalent attachment resulted in significantly higher immobilization efficiency (up to 1068 mg/g) compared to the CA system. The magnetic properties of Fe₃O₄ allowed for rapid recovery of the biocatalysts using an external magnetic field. These results highlight the effectiveness of ICT-based functionalization for enzyme immobilization, positioning Fe₃O₄/5ASA as a promising platform for robust and reusable biocatalysts in environmental and industrial applications.

Abstract: The Kabachnik–Fields (KF) reaction is a versatile three-component condensation of amines, carbonyl compounds, and P–H reagents, enabling efficient synthesis of α-aminophosphonates—key bioactive and functional molecules. This review critically examines the literature of the last 25 years, with the exception of selected mechanistic studies, highlighting mechanistic insights. Advances in catalyst-free methodologies, sustainable synthetic approaches, Lewis and Brønsted acid catalysis are discussed, alongside developments in enantioselective KF reactions in the presence chiral metal complexes or organocatalysts.

Abstract: Terpyridines are well-known ligands in coordination chemistry due to their conforma-tional flexibility and strong metal-binding properties; therefore, they serve as attractive platforms for the design and synthesis of new functional derivatives. This study focused on the synthesis and comprehensive investigation of a new class of bis-oxazolo[5,4-b]pyridine derivatives, designed based on their structural similarity to terpyridines. Four novel compounds 4a–d were synthesized by cyclization of amide de-rivatives of 3-aminopyridin-2(1H)-ones using pyridine-2,6-dicarboxylic acid and its di-chloride as key acidic components. Their structures and purity were confirmed by melt-ing point analysis, high-resolution mass spectrometry, and detailed 1H NMR spectros-copy. Photophysical studies in chloroform, dichloromethane, and acetonitrile revealed that compounds 4a–c exhibit intense blue to deep blue fluorescence (л_max 323–347 nm) with high quantum yields (φi ≈ 0.32–0.84), attributed to р–π* transitions within the con-jugated ring system. These findings suggest their potential as air-stable phosphors for organic electronics. Computational modeling of 4a–c molecules provided insight into their electronic structures, conformational stability, and predicted optical behavior. The most stable conformers (4a–II, 4b–II, 4c–II′) showed decreasing HOMO–LUMO gaps and photoactivity from 4a to 4c, with 4a–II emerging as the most promising fluorophore due to its high symmetry and consistent emission. Overall, this study lays the foundation for future studies of bis(oxazolo[5,4-b]pyridine) derivatives in coordination chemistry and optoelectronic materials development.

Abstract: Fulgides are a group of organic compounds that exhibit photochromic properties both in solid state and in solutions. The compounds attracted research attention due to their wide potential applications including photochromic eyewear, smart windows, optical switch, data storage, chemical and biological sensors. We are reporting here the synthesis and crystal structures of fulgides of four different substituents at the para position of a phenyl moiety in the molecules. It was found among the 4 structures that 1) all the 4 compounds packed in space groups of an inversion center; 2) the distance between the two carbon atoms C8 and C11, which form a single C-C bond in the cyclized products, falls in the range of 3.5-3.7 Å; 3) the torsion angle, defined by C6-C3-C4-C11, falls in the range of 23.4o to 32.5o. The fulgides exhibited photochromism. The fulgides should have no ferroelectric property due to their crystallization into centrosymmetric spaces groups.

Abstract: The valorization of agricultural residues helps improve crop economic efficiency and alleviate environmental pressures. Owing to the merits of simplicity, high efficiency, low costs, and scalability, adsorption removal of contaminants using biochar has been widely investigated. The adsorption removal of organic and inorganic contaminants from wastewater using biochar derived from agricultural residue follows the principles of the circular economy and green chemistry, facilitating both environmental remediation and agricultural development. This review outlined the mechanism of biochar adsorption, the preparation of biochar from agricultural residues, and their applications for wastewater remediation. Furthermore, the economic evaluation and environmental impacts, as well as the future directions and challenges, in this field, have also been presented.

Abstract:

This computational study investigates the thermal decomposition of 1,2,4-triazol-3(2H)-ones and their thione analogues using Density Functional Theory (DFT). The reaction proceeds via a concerted, six-membered cyclic transition state, primarily driven by the breaking of the N–N bond. A key finding is that the accuracy of the calculated activation energies (Ea) strongly depends on the choice of the DFT functional. For sulfur-containing systems (thiones), the hybrid functional APFD (with 25% Hartree-Fock exchange) provides the most reliable results, effectively describing their higher polarizability. In contrast, for oxygen-containing systems (triazolones), the dispersion-corrected functional B97D-GD3BJ (with 0% Hartree-Fock exchange) delivers superior accuracy by better modeling electrostatic and dispersion interactions. The -CH₂CH₂CN group at the N-2 position acts not only as a protecting group, but also stabilizes the transition state through non-covalent interactions. Electron-withdrawing substituents slightly increase the Ea, while electron-donating groups decrease it. Sulfur analogues consistently show significantly lower activation energies (by ~40 kJ/mol) than their oxygen counterparts, explaining their experimentally observed faster decomposition. This work establishes a dual-methodology computational framework for accurately predicting the kinetics of these reactions, providing valuable insights for the regioselective synthesis of biologically relevant triazole derivatives via controlled pyrolysis.

Abstract: This study investigated the properties of red algae (RA) biocomposite films reinforced with natural sisal fibers and plasticized with glycerol. The polymer was extracted from locally sourced red seaweed and combined sisal fibers at varying loadings (0–45 wt%) using the doctor blading technique. Composite films were analyzed using a variety of methods to evaluate the chemical composition, thermal behavior and mechanical perfor-mance. Infrared spectroscopy confirmed the presence of kappa-carrageenan as the domi-nant polysaccharide in the RA matrix, whereas elemental analysis verified the dilution of sulfur content and enrichment of carbon with increasing fiber incorporation. Thermal analysis revealed that thermal stability increased with fiber loading, peaking at 30 wt% sisal fiber before decreasing slightly at 45 wt% due to poor fiber dispersion. Mechanical testing demonstrated an optimal balance between strength and flexibility at 30 wt% sisal fiber, where tensile strength and modulus improved increased by more than 40% com-pared to the pure RA film. Overall, the findings demonstrate that sisal fiber reinforcement enhances the structural integrity and stability of RA-based films, supporting their poten-tial as biodegradable alternatives to petroleum-based plastics.

Abstract: The development of Multi-Target-Directed Ligands (MTDLs) offers a compelling therapeutic strategy for multifactorial diseases like cancer and Alzheimer's disease (AD), which share pathological pathways, notably microtubule abnormalities. This study introduces and validates a state-of-the-art computational pipeline, the QSAR-MD-DCCM workflow, designed to accelerate the discovery of dual-acting agents targeting tubulin polymerization and acetylcholinesterase (AChE). Two highly predictive QSAR models (R2 > 0.83), built upon the trimethoxyphenyl scaffold, guided the rational design of 16 novel compounds. Subsequent ADMET screening identified compounds 15 and 16 as optimal leads, demonstrating excellent physicochemical properties and CNS penetrability. Molecular docking and rigorous 100 ns Molecular Dynamics (MD) simulations confirmed strong, persistent binding to both targets (PDB ID: 4O2B for tubulin; 1EVE for AChE), with the compounds showing complementary, target-differentiated potency. Subsequent MM-GBSA/MM-PBSA binding free energy calculations provided the essential energetic validation, confirming highly favorable binding for both leads. Crucially, Dynamic Cross-Correlation Map (DCCM) analysis provided novel mechanistic insights into the functional allosteric coupling of residues upon ligand binding, reinforcing the stability and distinct dynamic modes of action for both compounds. This integrated methodological approach successfully delivered two highly validated virtual MTDL candidates, establishing a robust and predictive platform for accelerating dual-target drug discovery.

Abstract: Uric acid (UA), the end product of purine metabolism in humans, is a crucial biomarker closely associated with various diseases. This study developed a novel enzyme-free colorimetric sensing platform based on starch-derived nitrogen-doped biochar (NC) for the highly sensitive and selective detection of UA in human body fluids. The NC material with a high specific surface area and abundant nitrogen active sites was prepared via a two-step strategy involving hydrothermal synthesis followed by high-temperature pyrolysis, using starch and urea as raw materials. It efficiently catalyzed dissolved oxygen to generate reactive oxygen species (·O2- and 1O2) under mild conditions, which oxidized 3,3',5,5'-tetramethylbenzidine (TMB) to produce a blue-colored product (TMBox). UA reduced TMBox back to colorless TMB, resulting in a decrease in absorbance at 652 nm, enabling the quantitative detection of UA. Key reaction conditions were systematically optimized. Material characterization and mechanistic investigations confirmed the catalytic performance. The method demonstrated a wide linear range of 10-500 μmol·L-1 and a low detection limit of 4.87 μmol·L-1, along with excellent selectivity, stability, and reproducibility. Practical application in human serum and urine samples yielded results consistent with clinical reference ranges, and spike-recovery rates ranged from 95.5% to 103.6%, indicating great potential for real-sample analysis.

Abstract: In this study, a straightforward strategy for the preparation of functional carbon-based materials for hydrazine oxidation (HzOR) is presented. A highly efficient, cost-effective iron (Fe) and manganese-iron (MnFe) supported nitrogen-doped carbon (N-C) material was developed using a hydrothermal synthesis method. Meanwhile, N-C material was obtained from biomass – birch-wood chips – using hydrothermal carbonisation (HTC), followed by the activation and nitrogen doping of the resulting hydrochar. The material has a large specific surface area of 2431 m2 g−1 and a micro-mesoporous structure con-taining over 50% mesopore volume. The morphology, structure, and composition of the MnFe, MnFe/N-C, and Fe/N-C catalysts were determined using scanning electron micros-copy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray spectroscopy (EDX). The activity of the catalysts for the HzOR in an alkaline medium was evaluated using cyclic voltammetry (CV). The deposition of MnFe particles on N-C has been shown to result in a significant enhancement of electrocatalytic activity for HzOR in comparison with pure MnFe particles. The hydrazine oxidation current density values, measured at an electrode potential of 1.6 V vs. RHE, were found to be approximately 7 and 9 times higher on the Fe/N-C and MnFe/N-C catalysts, respectively, than on the MnFe catalyst.

Abstract:

This review provides an integrated analytical overview of the phenolic constituents of Solenostemma argel, with emphasis on extraction efficiency, structural characterization, and antioxidant-linked bioactivity. Because direct studies on argel phenolics remain limited, a broadened inclusion strategy was adopted. Studies were considered when phenolic-solubilizing solvents were used, when antioxidant-related biological effects (such as antidiabetic, anticancer, or neuroprotective activities) were evaluated, or when chromatographic and spectroscopic techniques applicable to phenolic analysis were employed. Comparative findings indicate that moderately polar solvents—particularly ethanol, methanol, and acetone—produce the highest phenolic yields, especially under ultrasound- or microwave-assisted extraction conditions. Reported variations in total phenolic content (TPC) primarily reflect methodological differences; however, higher TPC values consistently correlate with stronger antioxidant activity across assays. Advanced analytical platforms, including HPLC and NMR, provide the highest accuracy for qualitative and quantitative characterization of major phenolic classes. Overall, this expanded review synthesizes current evidence on phenolic profiling, extraction methodologies, analytical applicability, and antioxidant potential of S. argel, underscoring the plant’s promise as a rich and underexplored source of bioactive phenolic compounds.

Abstract: High-resolution NMR spectroscopy is the leading method for determining nuclear magnetic moments. It is designed to measure stable nuclei that can be investigated in macroscopic samples. In this work, we discuss the progress in research into light nuclei from the first three periods of the Periodic Table and several selected heavy nuclides. New 1H and 3He nuclei using the Penning trap method are also considered. Both nuclei can be used as references in gaseous mixtures. Gas-phase NMR spectroscopy enables precise measurements of the frequencies and shielding constants of isolated single molecules. They can be used to determine new, accurate nuclear magnetic moments of nuclides in stable, gaseous substances. Particular attention is paid to the importance of diamagnetic corrections for obtaining accurate results. Finding precise diamagnetic corrections - shielding factors, even in the case of light nuclei in molecules, is a big challenge. Up to now, nuclear moments have been obtained primarily from experimental results. The theoretical approach is mostly unable to predict these values accurately. Some remarks are also made on pure theoretical treatments of nuclear moments.

Abstract:

The main limitation of high-temperature drawing approach for tailoring crystallization and molecular orientation of poly-l-lactide (PLLA) toward ultrasound- active piezoelectric structures is set by intrinsic properties of the processed polymer, including low melting / softening elasticity and slow crystallization kinetics. Here we found that application of different contacting layers, including polytetrafluoroethylene (PTFE) (as Teflon and Teflon S), cellulose (paper) or polyimine (Kapton) deposited at the surface of PLLA, significantly affects the drawing process and tailors its oriented crystallization and molecular chain orientation. Consequently the contacting layers contribute to piezoelectric properties of PLLA, affect their activation by ultrasound and generated electro-signal. Human keratinocytes (HaCaT cells) grown stimulated on these surfaces are shown to receive and respond to the transferred stimuli by activation of the cytoskeleton and directional migration. The high-temperature drawing approach with contacting layers is simple, solvent-free and economically continent way for broadening limitations of classical high-temperature drawing which opens new possibilities for further tailoring piezoelectricity of organic piezoelectrics.

Abstract: Distribution water-extractable particulate (colloid) organic matter (WEOM) in narrow (nano- to micrometer) size fractions of chernozem soil by sequential filtration on track-etched membranes were studied. Multimodal (IR and fluorescence) two-dimensional correlation (2D-COS) spectroscopy was used. Protocols for attenuated total reflectance (ATR) FTIR of WEOM are proposed. ATR-FTIR 2D-COS provides larger volume of information on characteristic bands compared to traditional FTIR, especially in C–H ranges (3000–2800 and 1450–1300 cm–1). Fluorescence excitation-emission-matrix 2D-COS showed that the indexes and ratios of humic- to protein-like compounds are reproducible, exhibit significant variation among size fractions, with maximum amounts of saturated humic-like compounds in the largest (2–10 μm) and finest factions (0.01–0.03 μm) while medium fractions (0.05–1 μm) are dominated by fulvic acids and fresh organic matter. Heterospectral fluorescence–IR 2D-COS enhanced the accuracy of identification and assessment of WEOM group composition and showed that C–H IR band intensities correlate with tyrosine-like EEM bands and biogenic fluorescence in-dexes, while carboxylic components, with humate-like bands and humification fluo-rescence indexes. Element profiles in WEOM fractions correlate with fluorescence in-dexes; humification indexes, with P, S, Cr, Mg, Ca, Cu, and Zn; biogenic, with Mg, P, Cr, Cd, K, S, and Ca.

Abstract: Cocoa bean shells (CBS) represent a significant by-product of the transformation of cocoa beans, constituting approximately 15% of the total cocoa bean weight. Recently, interest in exploring the potential of these shells as a sustainable source of functional ingredients for use in cosmetics and nutraceuticals has grown. The present study investigates Microwave-Assisted Subcritical Water Extraction (MASWE) as a green and fast technique to recover bioactive compounds from CBS. A flash extraction (five minutes) at 170°C yielded a maximum of 45.79 mg of gallic acid equiva-lents (GAE) per gram of CBS, which was higher than that obtained using conventional conditions (25.73 mgGAE/gCBS with 50% acetone solution). Additionally, the HPLC pro-file of the extract from MASWE revealed a significant increase in hydroxybenzoic acids and catechin, compared to the conventional extract. Following the optimization of the extraction process, seven distinct resins were examined to isolate a bioactive-enriched fraction: Sepabeads SP700 was found to be the most effec-tive resin for concentrating such compounds, increasing both methylxanthines and TPC selectivity up to 4.2-fold. This valorization approach integrating MASWE and downstream optimization offers an innovative strategy to recover added-value products in line with green extraction and nutraceutical innovation.

Abstract: Chronic and complex wounds, including diabetic foot ulcers, venous leg ulcers, burns and post-surgical defects, remain difficult to manage due to persistent inflammation, impaired angiogenesis, microbial colonisation and insufficient extracellular matrix (ECM) remodeling. Conventional dressings provide protection, but they do not supply the necessary biochemical and structural signals for effective tissue repair. This review examines recent advances in hydroxyapatite–collagen (HAp–Col) composite dressings, which combine the architecture of collagen with the mechanical reinforcement and ionic bioactivity of hydroxyapatite. Analysis of the literature indicates that in situ and biomimetic mineralization, freeze-drying, electrospinning, hydrogel and film pro-cessing, and emerging 3D printing approaches enable precise control of pore structure, mineral dispersion, and degradation behavior. Antimicrobial functionalization re-mains critical: metallic ions and locally delivered antibiotics offer robust early anti-bacterial activity, while plant-derived essential oils (EOs) provide broad-spectrum an-timicrobial, antioxidant and anti-inflammatory effects with reduced risk of resistance. Preclinical studies consistently report enhanced epithelialization, improved collagen deposition and reduced bacterial burden in HAp–Col systems; however, translation is limited by formulation variability, sterilisation sensitivity and the lack of standardised clinical trials. Overall, HAp–Col composites represent a versatile framework for next-generation wound dressings that can address both regenerative and antimicrobial requirements.

Abstract: Al–Al₄C₃ composites exhibit promising mechanical properties including high specific strength, high specific stiffness. However, high reinforcement contents often promote brittle behavior, making it necessary to understand the mechanisms governing their limited toughness. In this work, a microstructural and mechanical study was carried out to evaluate the energy storage capacity in Al–Al₄C₃ composites fabricated by mechanical milling followed by heat treatment Using X-ray diffraction (XRD) and CMWP fitting, the microstructural parameters governing the initial stored energy after fabrication were determined: dislocation density (ρ), dislocation character (q), and effective outer cut-off radius (Rₑ). Compression tests were carried out to quantify the elastic energy stored during loading (Es). The energy absorption efficiency (EAE) in the elastic region of the stress–strain curve was evaluated with respect to the elastic energy density per unit volume stored (Ee), obtained from microstructural parameters (ρ, q, and Re) present in the samples after fabrication and determined by XRD. A predictive model is proposed that expresses Es as a function of Ee and q, where the parameter q is critical for achieving quantitative agreement between both energy states. In general, samples with high EAE exhibited microstructures dominated by screw-character dislocations. High-resolution TEM analyses revealed graphite regions near Al₄C₃ nanorods—formed during prolonged sintering—which, together with the thermal mismatch between Al and graphite during cooling, promote the formation of screw dislocations, their dissociation into extended partials, and the development of stacking faults. These mechanisms enhance the redistribution of stored energy and contribute to improved toughness of the composite.