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Herein, we report the regio- and stereoselective synthesis of 5-alkylidene-pyrrolidin-2-one derivatives through an Ag (I) or Au (I)-catalyzed cascade reaction between linear alkynoic acids and primary amines. This protocol features excellent regio- and stereoselectivity, good functional group tolerance, broad substrate scope, good to high yields, and high bond-forming efficiency, thus providing an efficient and convenient route to a variety of 5-alkylidene-pyrrolidin-2-ones.

Municipal sewage sludge of particle size below 425 µm has been utilized as the feedstock for biodiesel production. The moisture content in sewage sludge was found to be 81.7% for raw sewage sludge, and it was reduced to 20.7% after oven drying overnight at 60°C. Ash content was found to be 9.12% in the sludge. Titanium dioxide (TiO₂) was used as the heterogeneous nanocatalyst. The size of TiO₂ nanoparticles was found to be in the range of 80–150 nm, and the shape of the nanoparticles was spherical in nature. Different parametric studies of transesterification reactions, such as catalyst dose, reaction time, temperature, and methanol-to-solid ratio (MS ratio), have been done. Transesterification of sewage sludge was conducted in the presence of different catalyst doses, such as 0.5%, 1%, 3%, 5%, 7%, and 10%. The reaction was continued for 10, 20, 30, 40, 50, 60, 70, and 90 min. The optimum value of the catalyst dose was found to be 5%, and the reaction time was 30 min. Reaction was tested at different temperatures, such as 30°C, 40°C, 50°C, 60°C, 70°C, 90°C, and the optimum value was found to be 40°C. Different MS ratios were maintained: 5:1, 10:1, 20:1, 30:1, 40:1, 50:1, and 60:1, and the optimum value was identified as 50:1. For quality determination of the biodiesel fuel properties, such as density, viscosity, flash point, fire point, aniline point, diesel index, and cetane number were also tested.

Alzheimer's disease (AD) is a neurodegenerative brain disease that affects tens of millions of people worldwide, and it is characterized by memory impairment and cognitive deficits. Acetylcholinesterase (AChE) inhibitors can improve cognitive ability and memory, and are currently the focus of research to treat AD. In this paper, 41 donepezil analogues are studied by QSAR models, the reliable HQSAR (q² = 0.825, r² = 0.962, N = 6, and SEE = 0.167) and Topomer CoMFA models (q² = 0.843, r² = 0.994, N = 6, and SEE = 0.098) are obtained. Both external validation and application domain also indicate the reliability of the models. Based on these two models, 33 new compounds are successfully designed through virtual screening; they have good theoretical inhibitory activity. The molecular docking results show that these compounds bind tightly to proteins. ADMET predictions also confirm that most of these compounds meet the medicinal requirements. Molecular dynamics (MD) simulations are performed for four new compounds, and the results further verify the reliability and stability of the new compounds. This study provides a theoretical guide for the use of AChE inhibitor to treat AD, and the new compounds designed are expected to be novel drugs for AD.

Elevated intracellular reactive oxygen species (ROS) levels are a characteristic feature of cancer cells and can be strategically exploited for drug delivery. In this work, ROS-responsive nanocarriers were developed through the biogenic synthesis of silver nanoparticles (AgNPs) using Catharanthus roseus flower extract. The resulting AgNPs were subsequently functionalized with lecithin (LEC) and polyvinyl alcohol (PVA) to yield Ag@LEC-PVA nanoparticles, which were then loaded with curcumin (CUR) to form Ag@LEC-PVA-CUR-NPs. Comprehensive characterization using UV–vis spectroscopy, FTIR, SEM-EDX, TEM-DLS, XRD, and TGA confirmed successful synthesis, functionalization, and drug encapsulation. In vitro drug release studies demonstrated that CUR release was markedly enhanced in the presence of hydrogen peroxide (H₂O₂), validating the ROS-responsive behavior of the system. The Ag@LEC-PVA-CUR-NPs exhibited potent cytotoxicity against MCF-7 breast cancer cells (IC₅₀ = 10.8 ± 0.35 µg/mL) and notable anti-inflammatory activity (IC₅₀ = 30.24 µg/mL). These findings highlight Ag@LEC-PVA-CUR-NPs as a promising biogenic-engineered nanoplatform for ROS-mediated drug delivery in breast cancer therapy, offering improved therapeutic efficacy and reduced systemic toxicity compared to conventional chemotherapy.

Addressing the urgent need for large-scale energy storage from grid-connected intermittent renewable sources like wind and solar power, this study focuses on reducing the hydrogen evolution reaction (HER) at the anode of an all-iron redox flow battery. We demonstrate that adding magnesium chloride (MgCl₂) creates a synergistic inhibitory mechanism under acidic chloride aqueous electrolyte solution conditions (pH −1.0 to 0.0). Electrochemical tests show that Mg²⁺ influences the kinetics of the Fe²⁺/Fe redox couple, improving reaction reversibility and slowing the charge transfer kinetics of the HER. Microscopic analysis confirms that MgCl₂ enhances iron deposition, resulting in deposits with a preferred (211) crystallographic orientation. The optimized battery system showed exceptional stability over 10,000 charge/discharge cycles, maintaining an average coulombic efficiency of 99% during the last 7000 cycles. This work offers an innovative approach for designing high-stability flow batteries by synergistically controlling electrolyte composition, electrode interfaces, and deposition behavior.

Metal catalysts stand in the central position for carbonyl hydrogenation reactions. Comparison of catalyst activities and stabilities on different metal catalysts is ubiquitous and greatly beneficial to the design and screening of metal catalysts. For the sake of finding fundamental distinctions and further intensifying the design and screening process, a integrated and rational comparison from macrokinetics to microkinetics is highly required. In this article, we outline a general method of comparing intrinsic kinetics and avoiding pitfalls on different metal catalysts in carbonyl hydrogenation and then walk through the major aspects of comparison, such as intrinsic initial rates, initial deactivation profiles, apparent kinetics, kinetic isotope effects, reaction mechanism, and microkinetics. Finally, a case study on the integrated and rigorous kinetic comparison in carbonyl hydrogenation reactions over different noble metal catalysts is carried out. Overall, this article is expected not only to highlight the great importance of comprehensive and reasonable catalyst comparison for carbonyl hydrogenation but also to extend the scope of such comparison strategy further to other catalytic reactions and other types of solid catalysts for effective catalyst design and screening.

The effectiveness of natural bentonite (BN), which was gathered from the Rif region in northeastern Morocco, in removing crystal violet (CV) dye from aqueous solutions was evaluated in this work. X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and nitrogen adsorption–desorption based on the Brunauer, Emmett, and Teller (BET) methods were among the analytical techniques used to analyze the material. It was discovered that variables, including temperature, solution pH, and contact time, affected the adsorption efficiency. Although equilibrium investigations were in line with the Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich (D–R) isotherm models, kinetic data fit the pseudo-second-order model quite well. The Langmuir separation factor (R_L) and the Freundlich constant (n) both indicated advantageous adsorption behavior. At room temperature, the highest adsorption capacity was found to be 50 mg g⁻¹. Furthermore, thermodynamic study revealed that the adsorption process was exothermic, spontaneous, and favorable.

While fluorescent polymers have demonstrated remarkable effectiveness in the visualization of latent sweat fingermarks, research and application in the crucial area of blood fingermark visualization remain relatively scarce. To bridge this gap, this paper delves into and reports the synthesis and characterization of a series of PF-SO10 (blue), PF-SO10-BT1(green), and PF-SO10-DTBT1 (red) fluorescent polymers. These multicolored polymers are characterized to contain excellent ultraviolet-exciting fluorescence properties, which lays a foundation for their forensic application in bloodstain visualization. Experimental results indicate that our multicolor fluorescent polymer solution can be precisely applied to enhance blood fingermarks on various complex substrate surfaces, including glass, metal, plastic, and ceramic materials, achieving effective coverage and enhancement. Notably, this method is verified to possess significant characteristics of high contrast and low background interference through semiquantitative grayscale analysis, enabling the enhanced ridge details of blood fingermark in complex surfaces with a wide range of applicability. This study thereby establishes a robust and versatile platform for high-contrast blood fingermark detection, offering promising implications for future forensic investigations and practical crime scene analysis.

Fabricating cost-effective and efficient photocatalytic materials for the degradation of organic pollutants is a significant challenge due to the intrinsic limitations of conventional photocatalysts. The present work describes a nanoporous NiFe layered double hydroxide/ZIF-7 (NiFe-LDH/ZIF-7) heterojunction photocatalyst that was successfully synthesized using a facile in-situ two-step hydrothermal method, to offer a promising solution to these limitations. The synthesis and the incorporation of NiFe-LDH to the ZIF-7 framework were affirmed by comprehensive structural and morphological characterizations, x-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible spectroscopy, and Fourier-transform infrared spectroscopy (FTIR). The photocatalytic activity of the NiFe-LDH/ZIF-7 composite was appraised with methyl orange (MO) dye degradation as a test pollutant at exposure to natural sunlight radiation. The synthesized composite provided a remarkable degradation performance of 93.9% in 100 min with the pseuodo-first-order rate constant of 0.03 min⁻¹, which was much better than pristine ZIF-7. NiFe-LDH/ZIF-7 showed excellent reusability with 85.3% efficiency after four cycles, and trapping experiments revealed superoxide radicals as the dominant species. The synergistic effect between NiFe-LDH and ZIF-7 components is related to the enhanced activity because it offers an effective photogenerated charge separation and creates a path for reactive species. This work not only reports high photocatalytic activities of NiFe-LDH/ZIF-7, but also provides a stimulus to the design of high-performance photocatalysts that have a high surface area to treat the wastewater.

Perfluorinated and polyfluorinated alkyl substances (PFAS) are manmade compounds that persist in the environment, defy decomposition, and accumulate in living beings. Global focus on PFAS degradation pathways is due to its hazards of environmental pollution, immune system disruption, liver damage, hormone abnormalities, and others. A gram-negative bacillus from PFAS-contaminated soils, Delftia acidovorans, may grow slightly with PFOA as a carbon source, suggesting a dehalogenase enzyme can break down the chemicals. This study will describe and annotate a hypothetical protein D. acidovorans' function (Accession no. WP_011137954.1). A comprehensive insilico approach was used for physicochemical characterization, functional annotation, subcellular localization, energy minimization, and protein structure prediction. According to domain, family, and superfamily links, evolutionary correlations, and sequence similarity, the protein dehalogenates. After active site prediction, molecular docking showed that PFAS compounds PFDA (Perfluorodecanoic acid), PFNA (Perfluorononanoic acid), and PFOS (Perfluorooctanesulfonic acid) gave −7.9, −7.7, and −7.3 kcal/mol binding affinity. Molecular dynamics simulations validated the stability and flexibility of the ligand and protein, with RMSD values ranging from 1.4 to 2.5 Å and RMSF values indicating minor structural changes in the protein. This research suggests that a putative protein working as a dehalogenase in D. acidovorans might be a biotechnological target for bioremediation to improve environmental safety and sustainability.