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Bimetallic Co–Ni co-doped carbon nitride catalysts (CoNi-CN) were prepared by a simple one-step thermal condensation method and used for photocatalytic nitrogen fixation. The obtained catalysts were analyzed by various characterization methods and DFT simulations. The results show that the metal is doped in the interstitial position by forming metal-N coordination bonds. Compared with mono-metal Ni-doped g-C₃N₄ (graphite carbon nitride), the addition of cobalt reduces the band gap energy and improves the electron–hole separation efficiency. In addition, the introduction of cobalt promotes the activation of nitrogen molecules and accelerates the transfer of electrons from the catalyst to the activated nitrogen molecules through the “Ni–Co–N bridge”. The NH₄⁺ formation rate of CoNi-CN is 1.8 mg·L⁻¹·h⁻¹·g_cat⁻¹, which is 4.5 and 1.5 times higher than that of neat and mono Ni-doped g-C₃N₄. This study provides a simple and effective catalyst preparation method for nitrogen photofixation.

Metal based nanocomposites have significant applications in energy storage devices, but graphene oxide-based nanocomposites are well known for their ability to improve electrochemical characteristics. So, electrochemical characteristics of synthesized SnBiCu@GO nanocomposite were investigated and thoroughly examined utilizing a number of techniques. Cyclic voltammetry and electrochemical impedance spectroscopy were used to examine the electro-oxidation behaviors of methanol and ethanol on SnBiCu@GO-modified electrode in an alkaline media at different concentrations of KOH, NaOH, and KNO3. When compared with different electrolytes, the SnBiCu@GO nanocomposite with KNO3 electrolyte exhibited improved electrocatalytic efficiency and durability towards the oxidation of methanol and ethanol. The value of “n”, notably with n = 6 for methanol and n = 12 for ethanol, determined the electrocatalytic behavior of nanocomposite. The methanol oxidation reaction showed the highest and more consistent electrocatalytic activity, followed by ethanol oxidation reaction. Cyclic voltammogram data served as the basis for evaluation of diffusion coefficient and rate constant. Based on outcomes of both approaches, the diffusion coefficients were measured within range of 10^-13 to 10^-10 cm²/s and the rate constant ranged between 10^-7 to 10^-5 cm/s. Charge transfer resistance (R_ct) was found within range of 13–78 Ω and solution resistance (R_s) found within range of 0.002–168 Ω.

Schiff bases are privileged azomethine pharmacophores with diverse bioactivity. In this report, two new hydrazine-derived Schiff bases, L₁ and L_2, were synthesized. The structures were confirmed by experimental approaches involving IR, UV–vis, ¹H, and ¹³C NMR spectroscopy and showed strong correlation with theoretical computational predictions. Molecular reactivity was explored using DFT (B3LYP/6-311G(d,p), SMD/water) through frontier orbitals, electrostatic potential, and global reactivity descriptors. Antibacterial evaluation against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa showed strain-selective potency: L₁ was most active against S. aureus and E. coli (MIC 4.9 and 6.5 µg/mL), while L₂ displayed moderate activity against P. aeruginosa (MIC 8.4 µg/mL). Ciprofloxacin remained the strongest reference (MIC 0.049–0.521 µg/mL). Docking with DNA gyrase (PDB ID 6F86) indicated favorable binding for L₁ (−6.4 kcal/mol) and L₂ (−6.0 kcal/mol) vs. ciprofloxacin (−7.0 kcal/mol). ADMET predictions supported acceptable drug-likeness and low toxicity. These results highlight hydrazine-based Schiff bases as promising leads for antibacterial design against multidrug resistance.

Obesity, a chronic illness, is associated with long-term disability, hospitalization, diminished quality of life, and mortality, serving as a risk factor for numerous chronic ailments, such as hypertension, elevated cholesterol levels, stroke, heart disease, kidney disease, amputation, specific cancers, and arthritis. Therefore, there is a pressing need for new anti-obesity agents. Thus, a series of pyrazole 4-carbaldehydes and their cyanoacrylate derivatives were synthesized and evaluated for their inhibitory potential against α-amylase, lipase, and trypsin enzymes, along with their serum protection efficacy. Comparative structure-activity relationship analysis revealed that meta-substituted cyanoacrylates exhibited markedly superior α-amylase and lipase inhibitory activities than their para-substituted analogs, exemplified by compounds ethyl-2-cyano-3-(3-(3-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)acrylate (53.42%) and ethyl-3-(3-(3-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)-2-cyanoacrylate (51.46%), respectively. Furthermore, in the statistical analysis, the F-values and p-values were as follows: trypsin – F = 38.35974, p < 0.0001; amylase – F = 99.26896, p < 0.0001; lipase – F = 9.866327, p < 0.0001; and SPp – F = 37.52078, p < 0.0001.

Herein, p-type delafossite CuCrO₂ catalysts were synthesized at various calcination temperatures (900, 1000, 1100, and 1200 °C), then characterized and evaluated for hydrogen production through photocatalytic methods, with an optimization of the reaction medium. Their textural and structural characteristics were assessed using various physicochemical methods, including XRD, BET, SEM-EDS, and XPS. Optical and electrochemical properties were also evaluated by UV–visible spectroscopy, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and capacitance-potential measurements (Mott-Schottky analysis). It was shown that calcination temperature has a significant effect on these structural, textural, optical, and electrochemical properties, as well as on the materials' reactivity. The 3-R delafossite CuCrO₂ structure was obtained starting from 900 °C, with crystallite sizes almost independent of calcination temperature. Electrochemical studies confirmed the p-type nature of all samples. Optical, physical, and photoelectrochemical parameters were correlated to construct the energy diagram for evaluating the CuCrO₂ delafossite's ability to produce H₂. In a neutral medium (Na₂SO₄), the best activity was attributed to the preparation calcined at 1200 °C (CC1200) attributed to its structural and electrochemical stability, while in a basic medium (NaOH), the catalyst calcined at 1100 °C (CC1100) produced the highest amount of H₂, combining a small crystallite size and a bandgap conducive to efficient light absorption.

The aim of this study is to develop and characterize biodegradable biocomposites based on polylactic acid (PLA) reinforced with walnut shell particles. Composite specimens were fabricated via compression molding with walnut shell loadings ranging from 10% to 50%. A comprehensive suite of analyses was conducted, including scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), tensile and impact mechanical tests, and acoustic emission (AE) monitoring to elucidate fracture mechanisms. Results demonstrated that the addition of walnut shell reduced tensile strength and maximum elongation, while maintaining acceptable stiffness at intermediate loadings. Thermally, the biocomposites exhibited multi-stage degradation and remained stable up to approximately 200°C. AE results indicated a transition from ductile to brittle fracture behavior as the reinforcement content increased. In conclusion, PLA/walnut biocomposites present a balanced combination of functional performance and sustainability, making them promising candidates for biodegradable packaging, agricultural applications, and low-load structural components.

Phase-pure cubic spinel MgFe₂O₄ nanoparticles were synthesized via a hydrothermal route, followed by calcination at different temperatures (600 –1000°C) to investigate their structural evolution and gas-sensing performance. X-ray diffraction analysis confirmed that calcination at 1000°C yields a single-phase MgFe₂O₄ structure with improved crystallinity, preferential (311) orientation, and an average crystallite size of 57 nm. Increasing calcination temperature resulted in reduced microstrain and dislocation density, indicating enhanced structural stability. Optical studies revealed a slight narrowing of the band gap from 2.05 to 2.03 eV due to improved crystallinity and cation redistribution. Thick films fabricated using the optimized MgFe₂O₄ sample exhibited pronounced selectivity toward H₂S gas. The sensor demonstrated a maximum response of 89.5% for 500 ppm H₂S at an operating temperature of 250°C, along with a rapid response time and a shorter recovery time. These results indicate that hydrothermally synthesized MgFe₂O₄ is a promising material for reliable and selective H₂S gas sensing applications.

Corrosion poses major challenges in both everyday life and industrial applications; efficient corrosion control methods are essential to reducing expenses. This is the first study to computationally investigate the potential of novel benzoylthiourea derivatives (B1–B6) for corrosion. The current work is innovative in that it uses a variety of methods: DFT/B3LYP/6-311G++(d,p) level of theory was applied to compute electronic structure, quantum chemical parameters, and charge density; Multiwfn software shows electron localization function (ELF), localized orbital locator (LOL), density of state (DOS), reduced density gradient (RDG), and non-covalent interaction (NCI); MC simulations in dry, acidic environment (160H₂O, 4H₃O⁺, 4Cl^–) to estimate interactions on the Fe(110) surface. It was established that B1, B5, followed by B3, exhibit the best results for HOMO donor⟶LUMO acceptor, chemical activity, stability, and inhibitor efficiency. The MC simulations predicted adsorption energy of B5 in the acidic environment is about 37.51 times larger than in the dry environment, and most promising candidates among the series of compounds are more critical for forming a protective barrier application and inhibiting corrosion.

An alternative path to obtain three terminally functionalized sphingosines with acetylene, aldehyde, and carboxyl functions using olefin metathesis as a key step is reported. All these analogues of natural sphingosine can be used for imaging or derivatization.

Novel purine-based piperazine analogs were rationally designed and synthesized using fluoro-substituted benzoyl chloride as a key intermediate. The synthesized compounds were characterized and evaluated for their potential anti-tubercular activity. In vitro biological screening revealed that compounds S1C, S1D, and S1F exhibited significant antimycobacterial activity, with MIC values ranging from 8.5 to 18.8 µg/mL. To gain molecular insights into their mechanism of action, molecular docking studies were performed against UDP-N-acetylenolpyruvoylglucosamine reductase (MurB) from Mycobacterium tuberculosis. The docking results demonstrated favorable binding affinities, characterised by key hydrogen bonding and hydrophobic interactions at the active site. Additionally, 100 ns molecular dynamics simulations were conducted to assess the stability of the protein–ligand complexes. ADME profiles were predicted using the PreADME server, suggesting acceptable pharmacokinetic and pharmacodynamic properties. Overall, the biological evaluation, computational modeling, and favorable ADME profiles indicate that compounds S1C, S1D, and S1F are potential candidates for anti-tubercular drug development.