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Industrial dye contamination in water sources presents serious threats to both human health and the environment. Adsorption technology has gained popularity for wastewater treatment due to its simplicity, cost-effectiveness, and use of environmentally friendly materials. This study investigates the desorption of methylene blue (MB) dye using zinc oxide nanoparticles (ZnO-NPs) synthesized from ZIF-7 (Zn(BIM)₂; BIM = Benzimidazole) with a sodalite zeolitic topology. The green synthesis of ZnO-NPs was characterized using X-ray powder diffraction with Rietveld refinement (space group = P63/mmc, a = b = 3.252 (2) Å; c = 5.207 (4) Å, α = β = 90°, and γ = 120°), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) techniques, revealing a surface area of (29.93 g/m²), nanoscale size (3 nm), and surface hydroxyls. Under optimal conditions (pH 7, 10 mg/L dye concentration, 0.02 g adsorbent dose), ZnO-NPs achieved an adsorption efficiency of 94.7% for MB. Adsorption capacity increased from 62.7 mg/g at 298 K to 85.16 mg/g at 328 K, with isotherm analysis showing physical adsorption as the primary mechanism (adsorption energies <40 kJ/mol). Modeling revealed MB molecules adsorbed nonparallel to the ZnO-NP surface.

In this study, the core and periphery of the B₁₃⁺ cluster have been unveiled by employing a novel approach—Reduced Electron Density Analysis of adaptive natural density partitioning (AdNDP) Orbitals—to explore its rotor action. The central core of the cluster, acting as a “control unit”, governs the transformation between the ground state (GS) and transition state (TS). Core–peripheral electron density separation alongside AdNDP analysis has revealed how electron density shifts within the core dictate the cluster's structural transitions. For the first time, the reduced electron density of AdNDP orbitals provides a clearer visualization of the core's subtle rotational movements, offering an unprecedented look at the mechanism behind the GS-TS interconversion. The iso-surface plots highlight the influence of three core atoms, particularly one in the GS and two atoms in the TS, which serve as “master atoms” guiding the transformation. This work introduces a new methodology for investigating nanoscale transformations, laying the groundwork for future research in controlling nanomotors and designing advanced materials.

The rise in drug-resistant fungal infections has intensified the need for novel antifungal agents, particularly those targeting cytochrome P450 51 (CYP51) a key enzyme in ergosterol biosynthesis. This study explores the design, synthesis, and biological evaluation of 1H-indazole derivatives as potential CYP51 inhibitors. Structure-based virtual screening identified seventeen indazole-based candidates, which were further assessed for pharmacokinetic properties including absorption, distribution, metabolism, excretion, and toxicity (ADMET) using computational approaches. Two lead compounds, 1aa and 2aa were synthesized and evaluated for their antifungal activity against Rhizopus oryzae. Among them, compound 1aa exhibited superior antifungal efficacy with a minimum inhibitory concentration (MIC) of 128 µg/mL, while 2aa displayed an MIC of 256 µg/mL. In vitro assays confirmed that 1aa effectively inhibited ergosterol biosynthesis correlating with its strong binding affinity to the heme group of CYP51, as demonstrated by molecular docking and molecular dynamics simulations. These findings highlight 1aa as a promising lead compound for further optimization offering a potential strategy to combat antifungal resistance in clinical settings.

Alfa fiber is used as a low-cost precursor for the production of activated carbon (ACAF) through chemical activation with zinc chloride at 500 °C. In this context, ACAF was applied to the elimination of Cu(II) from water and compared with commercial activated carbon (CAC). The porosity, structural, and thermal stability were characterized by SEM, FTIR, BET, and TGA analysis. The surface oxygen functional groups were analyzed using Boehm's titration. Batch experiments in a stirred reactor were performed to study the effect of the operating parameters on the adsorption process: the pH (2–6), temperature (25–55 °C), and the amount of adsorbent (0.03–0.1 g). Isotherms models: Langmuir, Freundlich, and Dubinin–Raduskevich were tested. The results revealed that the ACAF had a high surface area of 1013 m²/g compared to the CAC adsorbent, 978.85 m²/g. The adsorption isotherms and the kinetics of Cu(II) onto both adsorbents can be described well by the Langmuir isotherm and pseudo-second-order models. The monolayer maximum capacity for ACAF and CAC toward Cu(II) were 41.666 and 21.276 mg/g at 328 K, respectively. Thermodynamics indicated that Cu(II) adsorption on ACAF and CAC adsorbents was spontaneous and endothermic. The adsorption mechanism of Cu(II) ions onto ACAF was an electrostatic interaction.

The cyclobutane ring stands as a remarkable structural motif, renowned for its presence in natural products and its unique reactivity in organic synthesis. Its inherent ring strain drives selective C─C bond cleavage and ring expansion, making it a compelling target for synthetic chemists. While [2 + 2] cycloaddition remains a classic method for cyclobutane construction, this approach is often unsuitable for intricately embedded cyclobutane moieties in complex natural products. To overcome these limitations, innovative synthetic strategies have been developed, bypassing direct cycloaddition to achieve precise and efficient cyclobutane assembly. This review highlights these methodologies and their transformative applications, expanding the synthetic repertoire for cyclobutane derivatives in organic chemistry.

An electrochemical sensor based on carbon nanomaterials doped with N/S and using cobalt as the metal source was proposed for the selective detection of dopamine (DA). Spherical nanostructures were efficiently and simply prepared via a solution self-assembly technique, and their electrocatalytic activity was investigated. The materials were characterized using various methods, followed by electrode modification and electrochemical experiments. The modified electrode exhibited excellent DA detection activity. Under optimal experimental conditions, the detection limit of the electrode was 4.0 × 10⁻⁸ mol L⁻¹, with a wide linear range of 3.0 × 10⁻⁷–7 × 10⁻⁴ mol L⁻¹. The sensor also exhibited excellent selectivity, stability, and reusability. This study suggests that electrodes modified by N/S doped carbon-based nanomaterials with Co as the metal source are promising for electrochemical sensor applications.

The effect of the second relative on the microgalvanic corrosion of AZ31B alloy was studied. The behavior mechanism of the second phase in corrosion was discussed by adjusting the area ratio of the second phase by heat treatment. The experimental results show that the corrosion sensitivity of the second phase region and the grain boundary is higher, and the samples with larger second phase area show higher electrochemical activity and faster corrosion rate in the corrosive environment. It is found that the microcouple effect between the second phase and Mg matrix accelerates the dissolution rate of the alloy. This study provides theoretical support for further understanding and improving the corrosion resistance of AZ31B alloy.

Bamboo's susceptibility to mildew leads to contamination and economic losses, underscoring the need for effective prevention methods. This study investigated the impregnation of bamboo with ionic liquids, specifically optimizing the pressurized process of dodecylpyridinium chloride, while evaluating treatment effectiveness and leaching resistance. Techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and ultraviolet–visible spectroscopy (UV) were employed to analyze the distribution and bonding of dodecylpyridinium chloride within the bamboo. The optimized impregnation parameters were determined to be a concentration of 6.88 mg/mL, a duration of 98 min, and a pressure of 0.61 MPa. Treated bamboo exhibited excellent antibacterial properties and leaching resistance, achieving 100% efficacy against bamboo mildew. Furthermore, after 14 days of soaking, the retention of dodecylpyridinium chloride decreased by only 27.3%. This study highlights a sustainable method for mildew prevention, which is crucial for enhancing the durability and utility of bamboo products.

Mycobacterium kansasii (Mkan) is a nontuberculous mycobacterium (NTM) commonly found in aquatic environments and is responsible for chronic pulmonary infections resembling tuberculosis. Treatment requires multiple antibiotics for at least 12 months, highlighting the challenge in managing Mkan infections. In this study, 50 thiourea derivatives were synthesized and evaluated for their cytotoxic and inhibitory effects on bacterial growth in culture and in infected macrophages using Mkan strains with varying virulence levels. In silico studies explored the structure–activity relationship (SAR) and the pharmacokinetic and toxicological profiles of the most active thiourea derivatives. As a result, 15 derivatives showed promising inhibitory activity against the reference strain, Mkan 12478. Of these, derivatives 2, 47, and 49 also significantly inhibited clinical isolates 10953 and 8835 without displaying cytotoxic effects. Furthermore, these three derivatives could inhibit intracellular mycobacterial growth in RAW 264.7 macrophages infected with strains 12478 or 8835. SAR studies revealed molecular volume and polar surface (PSA) area as important features for these thiourea derivatives, directly correlating with their antimycobacterial profile. In silico studies indicated that these compounds are potentially suitable for oral administration and have less toxicological effects than rifampicin, providing a safer alternative for antimycobacterial treatment. In conclusion, our findings suggest that thiourea derivatives 2, 47, and 49 are promising antimycobacterial agents for treating infections caused by Mkan.

Potassium periodate (KIO₄) catalyzed novel, efficient and highly regioselective one-pot synthesis of substituted benzimidazoles has been carried out in good to excellent yields via condensation–cyclisation reactions involving a variety of aldehydes and o-phenylenediamines. As a catalyst, KIO₄ shows good compatibility with various substrates, easy removal, easy handling, operational simplicity, and work in mild reaction conditions. A comparative study, microwave (MW) versus conventional method, for synthesizing 2-substituted benzimidazoles via KIO₄ catalysis is also described. It was observed that the microwave irradiation approach improves the yield and minimizes time (from hour to min), and represents more advantageous eco-friendly quicker chemistry.