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Dye wastewater causes significant harm to the environment and human health. Adsorption is one of the most effective technologies for treating dye wastewater owing to its straightforward operation, strong applicability, and low cost. However, traditional adsorbents have drawbacks, including complicated preparation processes, low adsorption capacity, and challenges with separation, recovery, and regeneration, which fail to meet practical application requirements. Therefore, the development of adsorbents with high adsorption capacity, easy separation, and reusability is urgently required for the treatment of dye-contaminated wastewater. Potassium methyl silicate (PMS)@MnO₂ complex particles (PMS@MnO₂) were successfully synthesized by adding a PMS solution to a potassium permanganate (KMnO₄) solution at a molar ratio of PMS to MnO₂ of 1:1. The PMS@MnO₂ complex is rich in functional groups and exhibits good hydrophobicity. The PMS@MnO₂ complex particles demonstrated excellent adsorptive capacity (989.1 mg/g) for methylene blue (MB) with rapid degradation, achieving over 75% of their adsorptive capacity within 5 min. The adsorption process was found to be pH-responsive and exothermic. Under neutral and alkaline conditions, the negative charges in the oxygen-containing groups on PMS@MnO₂ combine with the positive charges in the nitrogen atoms of MB via electrostatic forces. However, under acidic conditions, MB was adsorbed via hydrogen bonding and n-π interaction between MB and PMS@MnO₂. The spent adsorbent was reused for at least five cycles.

Dehydroabietic acid (DHAA) is a common natural product with a broad range of biological activities. In previous research, our group identified a range of dehydroabietic acid derivatives with strong anti-glioma activity. In order to search for better anti-glioma drugs candidates, new chalcone derivatives A1-A10 and B1-B10 were designed and synthesized in this study. The antiproliferative activity of these derivatives against U87 glioma cells was tested by CCK-8 assay, in which A10 has the best IC₅₀ value of 11.39 µM. Scratch and cloning studies further confirmed that A10 strongly inhibited the proliferation and colony-forming activity of U87 cells. The antiproliferative activity of A10 on U87 cells showed some concentration dependence manner and the pKa values of A10 were within the desirable range of anti-gliomas drugs. In addition, molecular docking revealed hydrogen bonding interaction was formed between A10 and the target protein. These results suggest that A10 may be a promising DHAA-derived lead compound that deserves further strategic optimization in search of the anticancer candidates against glioma.

Novel hydrazone ligand 2-(2-(2-hydroxy-5-methoxybenzylidene) hydrazinecarbonyl) pyridine 1-oxide was synthesized and characterized by spectral analyses. The assessment of number of dissociable protons in ligand and evaluation of corresponding values of pKa and the stability constants for M(II)-Ligand systems (M (II) = Cu, Co, Ni and Zn) in 30% DMF-water medium were done by adopting pH-metric method following Irving- Rossotti technique. To understand the chelation properties of hydrazone ligand, its contour maps of frontier molecular orbitals and their energies were computed using HyperChem 7.5 tools. The synthesized metal complexes of above hydrazone with Cu (II), Co (II), Ni (II) and Zn (II) were characterized with spectral and analytical techniques such as; FT-IR, 1H-NMR, LC-MS, TGA, UV-Vis, FE-SEM-EDX and ESR. The tridentate and dibasic nature of title ligand is ascertained from pH-metric studies as well as through the analyses of analytical and spectral data of complexes. The CT-DNA binding studies conducted adopting absorption and fluorescence titrations with metal complexes and ligand inferred their binding affinity through the mode of intercalation. The evaluated antioxidant and cytotoxicity properties revealed higher efficacy of copper complex. Furthermore, investigations employing molecular docking studies revealed non-covalent bonding interactions of synthesized compounds with chosen protein target CDK2.

The α- salicylate esters are found in natural products and play a vital role in biological processes. Understanding their structures and functions can provide insights into biochemical pathways and potential therapeutic targets. Herein, we have developed a strategy without the use of metal catalysts or additives for the chemoselective carbene insertion into COO─H bond over ─OH of salicylic acid. Salicylic acids were reacted with diazo compounds to yield α-salicylate esters at 150 °C. Having realized the importance of α-salicylate esters, we have generalized our strategy to various diazo compounds as well as salicylic and thiosalicylic acids. All the reactions produced expected products in good to excellent yields. It has been observed that salicylic acid reacted with diazo compounds in a chemoselective manner while thiosalicylic acid produced a mixture of products. The plausible mechanism of the reaction has been supported by DFT calculations and the origin of the chemoselectivity has been realized with the help of local Fukui functions. All the synthesized α- salicylate esters were isolated and characterized by sophisticated analytical and spectroscopic techniques including single crystal X-ray analysis.

Strategically engineering heterojunctions through the integration of two or more monolayer materials presents a promising avenue for augmenting the efficiency of solar-driven overall water splitting, which holds the potential for mitigating the escalating environmental challenges. Herein, based on first-principles calculations, the functional type-II g-C₆N₆/As heterojunction is first constructed by g-C₆N₆ and As, then, systematically investigated its structural stability, optoelectronic properties and photocatalytic mechanism and potential for catalyzing water splitting, respectively. Owing to the band-bending effect and the built-in electric field induced across the heterojunction interface, the photogenerated electrons and holes on the surface could effectively separate and extend their carrier lifetimes. The heterojunction as a type-II system photocatalyst with the hydrogen and oxygen evolution reactions occurring, respectively, happen at g-C₆N₆ and As surfaces. The heterojunction requires only an additional voltage of 0.29 V to ensure the photoinduced holes provide sufficient energy to drive the OER process. The introduction of single-layer As could effectively adjust the reaction energy barrier of the HER activity for single-layer g-C₆N₆, thus ultimately significantly enhancing HER performance of heterojunction. More significantly, the heterojunction breaks the optical-capturing obstacle of the g-C₆N₆ and exhibits strong optical capture capability in the regions from the infrared to visible light. Meanwhile, the value of the STH efficiency for heterojunction is up to 28.18%, which exceeds the value of the economically feasible requirement (10%). The above results are beneficial for the quantified design and application of photocatalytic heterojunction for overall water splitting and offer valuable insights for potential commercial implementations.

Bismuth titanate (BTI) nanoparticles were synthesized via hydrothermal method. The XRD spectra show that the maximum intense peaks are associated to orthorhombic Bi₄Ti₃O₁₂, and the pH did not show any significant effect on the structural transformation. The X-ray photoelectron spectrum (XPS) of BTI nanoparticles clearly shows the presence of elements like Bi, Ti, and O. It is noticed that the grain size is increasing from 64.9 to 97.0 nm with an increase in pH from 9 to 12. The TEM images evidenced the presence of spherical nanoparticles. The bandgap values are decreased from 3.201 to 2.595 eV (for pH = 9–12). The absorption spectra established a fact that the maximum absorption wavelength is decreasing from 218–225 nm with an increase of pH from 9 to 12. In case of BTI of pH = 12, the loss is noted to be 153.201, providing the dielectric absorber applications at high frequency. The M′ versus M″ plots show the partial relaxations, indicating the existence of carriers of partial relaxation strength and exhibit the non-Debye relaxations. The mass losses are increased for BTI samples till pH = 11, while the mass loss is decreased.

The introduction of electron-donating heteroatoms into mesoporous carbon is a strategy to significantly alter the electrochemical performance of supercapacitors. In this study, boron-doped mesoporous carbon spheres are synthesized by a high-temperature hydrothermal method, and boric acid is added during micro polymerization of phenol-formaldehyde resin microspheres to introduce boron atoms into the carbon backbone. Scanning electron microscopy (SEM) and transmission electron microscope (TEM) observations and N₂ adsorption tests verify the formation of a large number of mesopores in the porous carbon microspheres. The boron-doped mesoporous carbon has a specific surface area of 1458 m²g⁻¹. It possesses a specific capacitance in the three-electrode regime of 212.65 F g⁻¹ (at 0.5 A g⁻¹) in the three-electrode system. The supercapacitor device provided an energy density of 6.9 Wh kg⁻¹ at a power density of 149.9 W kg⁻¹. The capacitance retention after 5,000 cycles was 116.8%.

In the discovery of antiviral drugs, targeting the 3-chymotrypsin-like cysteine protease (3CLpro) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is advantageous for developing a broad-spectrum antiviral agent for the treatment of coronaviruses and other respiratory viruses, such as rhinoviruses. The promising biological activities of linear furanocoumarins reported in the literature, in addition to their quantum electronic properties, led to the in silico study of these compounds. Analysis of chemical reactivity descriptors of 3-methoxypsoralen (1) and 3,5-dimethoxypsoralen (2) using DFT and ab initio Hartree–Fock (HF) methods indicates that the compounds are more water-soluble, which is a favorable characteristic for clinical applications. Vibrational spectroscopy data are also presented. Molecular docking results revealed that 1 and 2 strongly bind to 3CLpro with relative affinities of −5.5 and −5.6 kcal mol⁻¹, respectively. They were also docked against the human rhinovirus HRV3C main protease, with relative affinities of −8.4 and −7.3 kcal mol⁻¹, respectively.

According to the research, zeolitic imidazolate framework (ZIF-67) and graphene oxide (GO) nanosheets were synthesized with a guar gum (GG) biopolymer substrate to form two-component hybrid biocomposites: GO/ZIF-67 (GOZ), GG/ZIF-67 (GZ), and three-component hybrid with GO/GG/ZIF-67 (GGZ) substrate polymer. These composites were used to adsorb malachite green (MG) cationic dye from an aqueous solution at room temperature. The chemical fractions, morphological and structural properties of the hybrid biocomposites were determined using a Fourier transform infrared spectrometer (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) analyses. The adsorption of MG dye was carried out on the two-component and three-component hybrid biocomposites with a polymer substrate under different experimental conditions. The high surface area of GZ, GOZ, and GGZ was 1362.89, 754.89, and 833.67 m² g⁻¹, respectively, and the total pore volume was 0.90 cm³ g⁻¹ for GZ, and 0.51 cm³ g⁻¹ for GOZ and GGZ, respectively. The removal of MG pollutant follows the pseudo-second order model and the Langmuir model. The adsorption mechanism involves hydrogen bonding, π-π stacking, and electrostatic interactions. The GOZ, GZ, and GGZ hybrid biocomposites showed the maximum removal efficiency at 66.6%, 74.4%, and 90.1%, respectively. The data show that the removal of MG after 3 cycles was 90%, 86%, and 82%.

The study aimed to investigate the effect of gastric acidic on color stability and surface hardness of resin-composites after 24 h acidic storage. Four bulk fill resin-composites (FiltekTM, SureFil SDR, Tetric N-Ceram, Beautifil Bulk) and one flowable composite (Dynamic Flow) were investigated using disk-shaped specimen for each study group before and after 24 h acidic storage (1.2 pH) at 37 °C. Color changes (∆E00) were evaluated using spectrophotometer at baseline (24 h post-irradiation: T1) and after 24 h of acidic storage (T2). Surface microhardness was measured at T1 and T2. The results inferred that, except FBF, all the study groups revealed significant and unacceptable color changes and reduction in microhardness. The ∆E00 ranged from 0.77 (FBF) to 28.73 (BBR) with FBF falls within an acceptable range (1.8). All the composites showed reduction in microhardness ranged from 20.48 (FBF) to 72.35 (BBR) with FBF showing the least reduction in microhardness. The data was analyzed by using one-way ANOVA followed by Tukey post-hoc analysis for multiple comparisons at a significance level of α = 0.05. Within the limitations of this study, FBF demonstrated better performance in acidic solution by showing the least color changes and reduction in microhardness as compared with other groups.