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The present study reports the systematic synthesis, characterization, and photocatalytic evaluation of germanium-substituted iron oxide (Ge_0.5Fe_2.5O₄) nanoparticles with varying concentrations of hyaluronic acid (HA). The synthesized nanoparticles were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analysis. The XRD confirmed the formation of Ge_0.5Fe_2.5O₄ with a crystallite size of 19 nm. The FTIR and SEM analysis verified the successful incorporation of Ge and HA into the iron oxide lattice. BET analysis revealed increased porosity upon HA addition, indicating potential benefits for catalytic applications. The photocatalytic efficiency of the nanoparticles was assessed using methylene blue dye degradation as a model reaction. Surprisingly, pristine Ge_0.5Fe_2.5O₄ exhibited an impressive 89.11% degradation rate, greater than (6% and 12%) HA-modified Ge_0.5Fe_2.5O₄ photocatalysts. These findings highlight the complex interaction between surface chemistry, porosity, and catalytic activity.

Phenolic resin is considered a promising precursor for advanced hard carbon anodes in sodium-ion batteries (NIBs) due to its ease of design, structural stability, and high residual carbon yield. However, the practical application of hard carbon is affected by its closed-pore content and structure. Here, we achieve fine control over the cross-linking structure of phenolic resin precursors by adjusting the catalyst content in the system, followed by high-temperature carbonization to produce phenolic resin-based carbon microspheres with small sizes (2–4 µm), monodispersity, and a narrow spherical diameter distribution. Based on this, we deeply explore the intrinsic relationship between the microstructure of these resin-based carbon microspheres and their sodium storage performance in NIBs. This strategy can provide a feasible molecular cross-linking engineering approach for the development of closed pores in phenolic resin-based hard carbon to tune electrochemical properties such as the plateau region capacity.

Oxy-bromination of cyclic amines to corresponding α,α’-dibromocycloamide(s) using bromide-bromate couple in aqueous acetic acid and at 60 °C (oil bath) is presented in the current work. A various types of cyclic amines were successfully oxybrominated during this work. Separation of the desired product by filtration therefore avoiding need of column chromatography, use of bromide-bromate couple as safe and stable source of oxy-bromination agent, mild reaction conditions and so on are the merits of the present research method. In silico ADMET and target prediction studies indicated that novel α,α’-dibromocycloamides possess satisfactory pharmacokinetic and pharmacodynamic profiles. The identified therapeutic targets provided a foundation for developing optimized molecules targeting therapeutically significant classes. The HOMO-LUMO energy calculations of the molecules using DFT method showed that Mole 3 and Mole 4 exhibited low gap energy and demonstrated high reactivity. However, Mole 5, Mole 6, Mole 7 and Mole 9 were found with high gap energy, thereby producing less reactivity or high stability. The high reactive molecules could be potential lead molecules which can interact efficiently with the drug targets. However, further experimental studies (in vitro/in vivo) are necessary to gain deeper insights into the pharmacological activities of these compounds.

Earlier, we have reported penicillic acid to be the major secondary metabolite from ethyl acetate extract of the broth produced by a fungal strain named as Penicillium polonicum. It exhibited high inhibitory activity against a plant pathogen Pythium aphanidermatum. In order to establish structure-activity relationship of penicillic acid, a series of chemical transformations of this constituent has been carried out under different reaction conditions, alteration of solvents and changing reagents. The yield was processed by various standard separation technique followed by preparative TLC and crystallization where it possible. The structural characterization of purified derivatives has been determined by chemical, spectral and spectrometric methods. The evaluation of antiproliferative activity of them was conducted on different human cancer cell lines. It has also been evaluated for antibiosis against P. aphanidermatum. The penicillic acid and dihydro-penicillic acid exhibited moderate activity against pancreatic (HPAC-1376), colon (HT-29) and thyroid (MDA-T32) cancer cell lines with IC₅₀ values 15.66/16.09, 18.74/18.37, and 19.18/19.17 µg/mL respectively. Unlike the parent compound and none of the derivatives viz. dihydropenicillic acid (2), bromohydroxy penicillic acid (3), dibromo-penicillic acid (4), bromosuccinmidyl-penicillic acid (5), bromohydro-penicillic acid (6), demethoxy-penicillic acid (7), sulphated-penicillic acid (8), hydroxyl penicillic acid (9), and bromo-amino penicillic acid (10) showed inhibitory activity against P. aphanidermatum.

With the continuous development of industry, the problem of water pollution is becoming increasingly serious. Methylene blue (Mb) is an important water pollutant that has a negative impact on ecosystems. Photocatalytic technology has been recognized as an effective and environmentally friendly method for solving water pollution, which has attracted widespread research attention. This study providing a solid experimental and theoretical basis for solving water pollution and has high research value. In this paper, MnTiO₃ with different molar ratios (Mn:Ti = 1:0.9 and 1:1) and different calcination temperatures (800, 900, and 1000 °C) was synthesized by sol–gel method. A systematic study was conducted on the structure, photodegradation performance, and photodegradation mechanism of synthetic materials. Research has shown that when the Mn:Ti ratio is 1:0.9 and the calcination temperature is 1000 °C/2 h, pure MnTiO₃ phase can be obtained. Among them, the MnTi_0.9O₃-900 °C/2 h sample composed of MnTiO₃, TiO₂, and Mn₂O₃ phases showed the highest photocatalytic degradation efficiency (54.3%) towards Mb. The mechanism of the excellent photocatalytic activity of MnTi_0.9O₃-900 °C/2 h is due to its narrow bandgap, porous structure, abundant oxygen vacancies, and heterojunction structure, which enhances light absorption and improves electron hole separation efficiency.

This study investigates the pharmacokinetic, physicochemical, and metabolite properties of 9b, a novel imidazopyrimidine-based sulfonamide previously shown to be effective against the A549 lung adenocarcinoma cell line. Aiming to evaluate its ADME (absorption, distribution, metabolism, and excretion) characteristics for drug development, the study found that 9b possesses favorable physicochemical properties, including a pKa of 12.35, LogP of 2.89, and LogD of 0.98. Stability tests demonstrated that 9b remains stable in human plasma and liver microsomes for up to 1 h, with moderate plasma protein binding (46%). Metabolite profiling using LC/Q-TOF MS revealed three major metabolites (M1, M2, and M3), whereas in vivo pharmacokinetic analysis via LC/QQQ-MS indicated optimal pharmacokinetic parameters, including C_max, T_max, AUC, and a half-life (t_1/2) consistent with a balanced pharmacokinetic profile. These results highlight 9b’s promising stability, moderate protein binding, and favorable metabolic profile, positioning it as a strong candidate for further development as an anticancer drug. Given its impressive pharmacokinetic properties and demonstrated efficacy in cancer cell lines, 9b shows significant potential for advancing cancer treatment.

Most nonconventional luminogens exhibit excellent water solubility and biocompatibility demonstrating unique potential for applications in areas such as biological imaging. At present, a series of cellulose based composite materials with photoluminescence (PL) emission properties have been reported, but there is still a lack of in-depth research on the PL emission behavior of the smallest unit of cellulose, D-(+)-Cellobiose (D-Cbs). Herein, with the help of cryo transmission electron microscopy (cryo-TEM), small angle X-ray scattering (SAXS), and theoretical calculation the PL properties and emission mechanism of the D-Cbs aqueous solution are elucidated through clustering-triggered emission mechanism. It is found that the size and distance of aggregates in solution was successfully associated with the cluster emission center. Meanwhile, D-Cbs can efficiently detect Fe³⁺ ions in mixed metal ions. These results not only closely correlate the real size and distance distribution of aggregates in concentrated solutions with their PL properties but also advance the development of the luminescence mechanism of such material solution systems.

The synthesis of diethyl carbonate (DEC) faces several challenges, including the difficulty in separating and recycling highly active organic alkali catalysts, poor catalyst stability, and high operational costs associated with traditional transesterification methods. Additionally, industrial transesterification processes often suffer from low production capacity and slow reaction kinetics. In this study, we explore the catalytic performance of various metal-compound-based catalysts supported on commercial activated carbon (AC) in a fixed-bed reactor. The development of highly stable and long-life catalysts reduces production costs, while ensuring efficiency, selectivity and stability, and provides a technical reference for the industry to realize continuous production. Among the tested catalysts, 4CaO/AC-600 exhibited the highest catalytic activity, achieving a DMC conversion of 94% and DEC selectivity exceeding 60% under optimal conditions. Characterization results suggest that the excellent performance of 4CaO/AC-600 stems from the following synergistic mechanisms: the strongly basic sites can drive the transesterification reaction efficiently; the porous structure promotes the active site dispersion and reactant diffusion; and the interaction between CaO and AC enhances the structural stability and electronic effect. Furthermore, this study offers valuable insights into the design of efficient catalysts for the industrial-scale synthesis of DEC.

The investigation of wettability and water adhesion of the gradient TiO₂ nanotubes surface can help to understand their manipulation process on droplets. Here, gradient TiO₂ nanotubes were prepared via bipolar anodization. The TiO₂ nanotubes prepared by 98 V 2 min⁻¹, 60 V 10 min⁻¹, and 30 V 30 min⁻¹ showed different gradient diameters. After modification by 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (FAS), the surfaces near the anode edge reached a superhydrophobic state. In the central area, the surfaces gradually became less hydrophobic. Water adhesive forces of the superhydrophobic regions were lower than 20 µN, while they increased as the contact angle decreased. Moreover, the region with high water adhesion could transform into a sliding superhydrophobic state with low adhesion through a heating process. This paper provides some new insights into the wettability and water adhesion of gradient TiO₂ nanotube surfaces.

The reaction of copper(II) chloride with azomethine ligand 4-(pyridin-2-yl)methyleneamino-1,2,4-triazole (L) yielded crystals of a 1D coordination polymer [Cu(L)Cl₂]_n (1), in whose structure metal atoms are bound by L molecules due to nitrogen atoms of imine, pyridyl, and triazole moieties. In contrast to this process, the reaction of zinc(II) chloride with L resulted in the formation of mononuclear complex [Zn(L)₂Cl₂]·H₂O (2), containing L molecules coordinated to the metal center in a monodentate mode due to triazole nitrogen atoms. The structures of the coordination compounds obtained were determined by single-crystal X-ray diffraction. The antimicrobial activity of 1 and 2 was assessed against the bacteria Escherichia coli, Staphylococcus aureus, Streptococcus spp., the fungi Candida albicans, Candida glabrata, Aspergillus fumigatus, Rhizopus oryzae, and the protozoa Colpoda steinii. Compound 1 showed high antiprotozoal activity, as well as significant antifungal activity against C. glabrata, and complex 2 demonstrated high bacteriostatic activity against Streptococcus spp. Thermal stability of 1 and 2 was studied by simultaneous thermal analysis under an argon atmosphere.