Search Results (1,136)

Metal doping is an effective strategy for tuning and improving the transport properties of semiconductors such as iron silicide. However, when the dopant concentration exceeds its solubility limit, secondary metallic phases can form, degrading the desired semiconductor properties and overall material performance. Therefore, a clear understanding of dopant solubility limits and phase stability is important for optimizing material properties. Here, we investigate the solid solution behaviors of metals in polycrystalline Fe_1−xM_xSi₂ (M = Mn, Co, and Ni) systems. The results show that increasing dopant concentration promotes the formation of metallic secondary phases and limits dopant incorporation into the β matrix. The estimated solubility limits are approximately 6.3% for Mn, 8.8% for Co, and 1.0% for Ni. Beyond the iron silicide system, the combined methodology provides a practical approach for determining dopant solubility in semiconductors, where local compositional saturation may occur before substantial changes in bulk phase fractions become apparent. Full article

There is an urgent and persistent need to design efficient and sustainable methods to manufacture chemicals on a large scale. Heterogeneous photocatalysts use light to drive organic reactions and offer high recyclability and improved efficiencies for chemical synthesis. However, a detailed study of these photocatalysts using standard laboratory analytical techniques is challenging due to their poor solubility. Successful application of heterogeneous photocatalysts in the chemical industry requires the development of a robust analytical technique that can be used as a predictive and scalable tool for their photocatalytic performance. Herein, we report a simple approach that uses the color of cotton-bound heterogeneous photocatalysts as a potential indicator of their performance. These photocatalysts were synthesized by covalently attaching perylene-based molecular photocatalysts to the surface of cotton using amino-substituted triethoxysilane as the linker. Colorimetry coupled with NMR analysis revealed two important findings: (i) cotton-bound photocatalysts catalyzed sulfide oxidation to sulfoxide under blue-light illumination, and (ii) a general relationship was observed between color intensity and catalytic performance, with darker samples generally exhibiting faster reaction rates. These findings suggest that color may serve as a simple and rapid tool for assessing photocatalyst performance. Future studies will focus on enhancing the reproducibility of photocatalyst binding procedures and validating the color–performance relationships in a wider range of color intensities of the cotton-bound photocatalysts. Full article

Relatively low-cost titanium carbide (TiC) materials and metal matrix composites (MMC) are proposed for waste-to-hydrogen conversion. Two types of steels are used as bases prepared from EN 10088 flat products, namely X2CrTi12 (1.4512, AISI 409) and X5CrNi18-10 (1.4301, AISI 304). TiC is mixed with TRIBALOY^® T-800 alloy in powder form and applied via laser-directed energy deposition (DED-LB) over the substrates. For the powder mixture, Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) are performed. The raw materials are investigated for the processes that occur in them under heating. After the solidification of the molten mixture, grinding and polishing are performed to achieve a thin layer. The studies of the obtained MMC include interface zone assessment, hardness and Young’s modulus distribution, microstructural analysis, and visual defect evaluation. Advanced sensors for acoustic emission (AE) and Electrical Contact Resistance (ECR) provided characterization together with micro-scratch testing. The use of photoluminescence spectroscopy is proposed for the new composite materials. The electron transfer pathway can be studied with time-resolved spectroscopy. Renewable energy production by breaking down waste into hydrogen-rich syngas can be achieved through pyrolysis, followed by steam reforming and purification. The obtained novel materials show promising application solutions with increased durability, corrosion, and wear resistance. Full article

This study focuses on the determination of pesticide residues in drinking water in Slovakia using the LC-MS/MS method, covering a target list of approximately 90 pesticides selected according to the national drinking water risk assessment. The aim of monitoring is to screen the presence of pesticide substances in various water supply systems and to gain experience for setting higher-quality criteria for the control of drinking water. Drinking water samples were collected in 2023, 2024 and 2025 within the National Monitoring Project of the Presence of Pesticides in Public Water Supplies, including both Large-Supply Areas (>5000 inhabitants—2023) and Small-Supply Areas (500–5000 inhabitants—2024, 2025). A total of 211 samples were measured and evaluated in 2023, compared with 199 samples in 2024. This article presents the evaluation of results for 2023 and 2024, while data for 2025 will be assessed in 2026. The findings contribute to the improved surveillance and quality control of drinking water. Full article

Metal-organic frameworks (MOFs) are porous crystalline materials composed of metal ions and organic ligands. By varying the combinations of metal centers and ligands, their structural properties, adsorption performance, and stability in aqueous environments can be tuned. Owing to these characteristics, MOFs have attracted attention as promising materials for environmental analysis and separation technologies. In this study, several MOFs with different metal ions and ligands were synthesized and evaluated for their adsorption performance for bensulfuron-methyl, a sulfonylurea herbicide. Among the tested MOFs, MIL-53(Al) exhibited the highest recovery. The results indicate that adsorption performance depends on the combination of metal ions and organic ligands. Full article

A novel 3,6-dicarbonyl-substituted derivative of 2-chloropyrazine has been synthesized for the first time via regioselective dilithiation using lithium 2,2,6,6-tetramethylpiperidide (LiTMP) and subsequent trapping with methyl benzoate. The structure was unambiguously confirmed through Sonogashira coupling and diagnostic NMR analysis, establishing selective substitution at both the 3- and 6-positions. This result demonstrates that symmetrical 3,6-functionalization of 2-chloropyrazine is feasible under mild conditions, overcoming long-standing limitations of multiple metalations in electron-deficient heterocycles and opening new pathways for the synthesis of polyfunctional pyrazine frameworks. Full article

Developing predictive models for drug efficacy is challenged by the complexity and heterogeneity of bioassay data. Here, we present LIFE.PTML, which is a methodology integrating drug Lifecycle (L), Information Fusion (IF), Encoding (E), Perturbation Theory (PT), and Machine Learning (ML) to predict compound activity across diverse experimental conditions. Using a dataset of 3748 molecule–assay combinations targeting calmodulin (CaM) and related proteins, LIFE.PTML combines chemical and protein descriptors, quantifies experimental variability via perturbation operators, and trains non-linear classifiers, including XGBoost and Gradient Boosting. XGBoost achieved the best performance, with 88.9% test accuracy and an ROC AUC of 0.959, while feature importance analysis highlighted contributions from both drug- and protein-level descriptors. The results demonstrate that LIFE.PTML provides a robust, flexible, and interpretable framework for predictive chemoinformatics, facilitating the integration of multi-source data for drug discovery applications. Full article

Type 2 diabetes mellitus remains a critical metabolic disorder requiring novel therapeutic approaches. In this work, a library of 1-deazapurine derivatives was evaluated as α-glucosidase inhibitors through molecular docking with MOE software. The three top-ranked ligands—Methyl 6-(2-hydroxybenzoyl)-3-(2-phenylethyl)imidazo[4,5-b] pyridine-5-carboxylate (–6.1247 kcal/mol), 5-(furan-2-yl)-3-(4-methoxybenzyl)-2-phenyl-7- (trifluoromethyl)imidazo[4,5-b]pyridine (–5.7030 kcal/mol), and 3-[2-phenylethyl]-5-thio phen-2-yl-7-(trifluoromethyl)imidazo[4,5-b]pyridine (–5.5403 kcal/mol)—were further validated by molecular dynamics simulations. ADMET and drug-likeness predictions confirmed favourable pharmacokinetic behaviour, gastrointestinal absorption, and oral bioavailability. These findings highlight 1-deazapurines as promising scaffolds for developing new α-glucosidase inhibitors targeting type 2 diabetes. Full article

This study investigates the application of natural chitosan as an efficient adsorbent for the removal of heavy metals from aqueous solutions. Experimental results showed that Mn(II), Co(II), and Ni(II) ions were effectively retained on the chitosan surface. Kinetic analysis revealed a preferential adsorption order of Co(II) > Mn(II) > Ni(II), following a pseudo-second-order model with rapid kinetics. Equilibrium adsorption capacities were influenced by initial concentration, temperature, and pH. Thermodynamic analysis indicated that the adsorption process was exothermic and physical in nature. Overall, chitosan proved to be a promising and cost-effective adsorbent for water decontamination. Full article

In this paper, quantum chemical calculations at the DFT/6-311G (d,p) level of theory have been carried out to study the supramolecular structure of dihydropyrimidin-2(1H)-ones. Theoretical studies such as Hirshfeld surface analysis, MEPS (molecular electrostatic potential surface), and HOMO–LUMO calculation were also carried out to obtain the energy gap and to determine the kinetic stability and chemical reactivity. The crystal structure of dihydropyrimidin-2(1H)-ones shows the present of N-H…O and O-H…O hydrogen bonding interactions. The N-H…O bond lengths are 2.102 Å and 2.037 Å, respectively. The theoretical hydrogen bonding interactions were also compared with the available experimental data and found to be closely related. Full article

Hybrid molecules, integrating multiple pharmacophores within a single scaffold, represent a modern strategy in drug discovery, offering improved selectivity and safety. Anthranilic acid is a versatile building block with diverse biological activities. In this work, we designed and synthesized novel anthranilic acid-based hybrids with enhanced pharmacokinetic potential. The methods used include cheminformatics- guided library design, followed by amide bond formation between anthranilic acid derivatives and substituted 2-phenylethylamines. Purification and structural characterization were achieved via NMR, IR, and HRMS. The compounds exhibited favorable, predicted ADME/Tox profiles and synthetic accessibility. These results provide a foundation for further biological evaluation toward therapies for smooth muscle dysfunction and inflammation. Full article