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关键词： Electrocatalysts   High-entropy alloys   Hydrogen evolution reaction   Laser irradiation   Lattice disorder  

摘要： Breaking lattice symmetry and optimizing surface reaction pathways through structural engineering to enhance the effectiveness of individual active sites is an efficient strategy for improving the catalytic performance of high-entropy alloys (HEAs). In this study, we innovatively introduced S doping and evaporation processes via laser irradiation to induce lattice disorder (from FCC to amorphous structure) in a CrCoNiZnIr HEA, generating a high density of grain boundaries and thereby forming a highly efficient bifunctional catalyst (CrCoNiZnIrS_1-x). S incorporation/evaporation created sulfur vacancies, which induced the “dynamic evolution” of active sites (CrIrNi→IrNi→Ir) while enhancing the catalytic efficacy of the Ir sites. It reduced the energy barrier for the oxygen evolution reaction (OER) at the *OH→*O reaction step and shifted the hydrogen evolution reaction (HER) pathway from the Volmer-Tafel (V-T) mechanism to the more efficient Volmer-Hayrovsky (V-H) mechanism. In-situ Raman and In-situ electrochemical impedance spectroscopy (EIS) confirmed the presence of rapid mass transport during OER. Consequently, the optimized catalyst exhibited a HER overpotential of 28 mV at 10 mA cm⁻² and overall water splitting (OWS) voltage of only 1.46 V. This work provides new insights into the synergistic regulation of catalytic performance through lattice engineering and active site evolution enabled by elemental doping, advancing the design and application of efficient and stable water-splitting catalysts.

关键词： 1-naphthol   2-naphthol   Content determination   Derivative technique   Synchronous fluorescence spectrometry  

摘要： Under alkaline conditions with sodium hydroxide (NaOH), both 1-naphthol (1-NAP) and 2-naphthol (2-NAP) transitioned from their molecular forms to ionic forms, resulting in redshifts of their fluorescence spectra. Thus, not only the interference of 2-NAP raman peak was eliminated, but the fluorescence intensity of two naphthols was also enhanced, thereby improving the selectivity and sensitivity of their analysis. Due to their structural similarity, the conventional fluorescence spectra of 1-NAP and 2-NAP overlapped and interfered with each other, precluding their simultaneous measurement without prior separation. In this study, the wavelength difference (Δλ) = 140 nm was selected for synchronous fluorescence spectrometry (SFS) scanning to simplify the spectra. However, the interference of 2-NAP on 1-NAP remained significant. So, the second-order derivative technique combined with SFS was adopted. The method that eliminated the severe interference between 1-NAP and 2-NAP and wastewater background by utilizing spectral parameters. Finally, a new second-order derivative SFS for simultaneous determination of 1-NAP and 2-NAP was first established. The detection limits were 0.0850 ng·mL⁻¹ for 1-NAP and 0.1066 ng·mL⁻¹ for 2-NAP, with linear ranges of 0.5–80 ng·mL⁻¹ and 0.5–50 ng·mL⁻¹, respectively. Recoveries of two naphthols in wastewater were 87.53%–93.50% (1-NAP) and 89.85%–104.00% (2-NAP). The new SFS established in this research has been successfully applied to the analysis and detection of 1-NAP and 2-NAP residues in wastewater, achieving satisfactory results. It is expected to become a new routine detection method for 1-NAP and 2-NAP.

关键词： Benzimidazole   Crystal structure   Hydrogen bond interactions   Hirshfeld surface analysis   DFT   NBO   Molecular docking   ADME-T  

摘要： In this study, a structural and computational investigation of ethyl 2-(6-nitro-1H-benzo[d]imidazol-1-yl)acetate (ENBIA) was conducted. The compound was synthesized via a condensation reaction between ethyl bromoacetate and 5-nitrobenzimidazole. Structural identification was carried out by FT-IR, NMR, SEM, EDX analyses and confirmed by X-ray diffraction techniques. The compound crystallizes in the monoclinic system, space group P2₁/n with stability maintained through C−H···N and C−H···O hydrogen bonds, along with additional stabilization from aromatic stacking and N−O⋯π interactions. Hirshfeld surface analysis indicated significant O⋯H/H⋯O (36.1 %) and H⋯H (32.6 %) interactions in the crystal structure. Energy frameworks analysis indicated the dominance of dispersion energy in molecular packing. The energy gap (E_gap) between HOMO and LUMO was found 4.484 eV, suggesting high chemical stability. The electronic properties were further evaluated using quantum chemical computations at the B3LYP/6–31G(d, p) level. Mulliken atomic charges distribution and molecular electrostatic potential (MEP) surface analysis showed the electron-rich/electron-deficient sites of the title molecule. Molecular docking studies revealed that ENBIA exhibits strong binding affinities toward multiple targets (−7.8 to −6.6 kcal/mol), with the highest for Keap1/Nrf2, stabilized by hydrogen bonding and π-interactions. ADME predictions indicated good absorption, moderate oral bioavailability, low BBB permeability, and balanced lipophilicity, while toxicity was low (WHO Class IV, LD₅₀ = 1500 mg/kg). These results highlight ENBIA as a stable, safe, and promising multi-target candidate for further evaluation.

关键词： 4-nitrophenol reduction   Amidoxime-functionalized PIM-1   Metal organic frameworks   Porous composite beads  

摘要： The widespread presence of toxic nitroaromatic compounds in industrial effluents demands advanced remediation strategies. Catalytic reduction is highly effective, while the practical application of powdered catalysts is limited by challenges in recovery and reuse. To overcome this issue, macroscopic Pd@NH₂-MIL-101/AOPIM-1 porous composite beads were fabricated via a phase inversion method, combining the high surface area of NH₂-MIL-101 with the excellent processability of amidoxime-functionalized polymers of intrinsic microporosity (AOPIM-1). The incorporation of NH₂-MIL-101 enriches the composite with amino functional groups, thereby enhancing the adsorption and local enrichment of reactants. Furthermore, these nitrogen-rich sites provide robust anchoring points for the uniform dispersion of Pd nanoparticles, collectively boosting catalytic activity and structural stability. The beads exhibited outstanding catalytic activity for the reduction of nitroaromatics, achieving 99% conversion of 4-nitrophenol (4-NP) within 5 min. The catalyst also maintained excellent structural stability over multiple cycles and allowed easy separation. Furthermore, the catalyst exhibited over 90% efficiency in the reduction of other common nitroaromatic pollutants, underscoring its versatility and applicability in wastewater treatment. This work provides a sustainable and practical solution for wastewater treatment by transforming hazardous contaminants into valuable aromatic amines using an easily separable catalytic system.

关键词： Surface and interfacial mechanism   Covalent organic frameworks (COFs)   MXene   4-NADH regeneration   CO 2 reduction  

摘要： Efficient regeneration of 1,4-nicotinamide adenine dinucleotide (1,4-NADH) without electron mediator is crucial for sustainable enzymatic CO₂ reduction. Herein, a vinylidene based TD-COF (TDC) was linked with aminated MXenes (Nb₂CT_x and Ti₃C₂T_x), to construct a serials of COF/MXene photocatalysts (TDC-Nb_a and TDC-Ti_b). Compared with TDC and TDC-Nb, TDC-Ti exhibited superior photocatalytic NADH regeneration yield and enhanced 1,4-NADH regioselectivity. In the absence of electron mediator, the optimized TDC-Ti_0.12 achieved a 1,4-NADH turnover frequency (TOF) of 0.71 h⁻¹, significantly outperforming the optimized TDC-Nb_0.18 (0.63 h⁻¹) and pristine TDC (0.15 h⁻¹). Systematic characterization, photoelectrochemical measurements, and density functional theory (DFT) calculations revealed two key factors driving this performance. First, the TDC/Ti₃C₂T_x interface displays a larger Fermi level difference than the TDC/Nb₂CT_x interface, resulting in lower exciton binding energy and stronger electron transfer driving force. Second, the TDC/Ti₃C₂T_x surface exhibits a greater difference in NAD⁺ adsorption energies between end-on and planar modes (2.17 eV) compared to TDC/Nb₂CT_x (1.61 eV), promoting regioselective NAD⁺ reduction via the end-on pathway and thereby enhancing 1,4-NADH selectivity. When coupled with formate dehydrogenase (FDH), TDC-Ti_0.12 delivered a formate production rate of 1485.1 μmol g⁻¹ h⁻¹ in CO₂ reduction, which is 2.3 times higher than TDC (651.7 μmol g⁻¹ h⁻¹) and even surpassing TDC with an Rh-based el

摘要： The presented study comprised the synthesis of a new series of 5-(5-phenyl-[1,3,4]oxadiazol-2-yl)-furan-3-ylamines (7a–p) using multistep reactions along with in vivo and in silico screening for their anticonvulsant potential. The synthesis of targeted compounds starts with the reaction of furan, trichloroacetyl chloride, and potassium carbonate in the presence of anhydrous ether as a solvent and subsequently leads to the formation of 4-amino-furan-2-carboxylic acid hydrazide (5). In the final step, 5 reacted with substituted benzoic acids to yield the target compounds (7a-p). The anticonvulsant potential of the synthesized compounds has been determined by using established anticonvulsant animal models, i.e., maximal electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) tests. The results indicated that compounds 7c, 7f, 7j, and 7n have strong protection against convulsions in both models. The neurotoxicity and antidepressant effects have also been determined by utilizing the rotarod and an actophotometer apparatus, respectively. The drug-likeness, ADMET profiles, molecular docking (against sodium channel IIA (1BYY), NMDA receptor NR1 (1PBQ), and γ‑aminobutyric acid (GABA)_A (4COF), and dynamic simulation studies of the synthesized compounds have also been determined to rationalize the relationship between structures, required physicochemical parameters, and binding affinities to the target proteins as good anticonvulsants. By using Density Functional Theory (DFT), it was also established that 7c, 7f, 7j, and 7n have stable electronic traits like a consistent HOMO-LUMO gap and a solid electrophilicity index. The GABA estimation in different lobes of rat brains suggests it has a role in the GABAergic pathway. Histopathological studies indicated no signs of breakdown, swelling, or damage, which suggests the synthesized compound is safe for the brain and spi

关键词： 1-Tetradecyl-3-methylimidazolium bromide   Drop motion   Glass   Marangoni stress   Reactive wetting  

摘要： Autonomous drop motion of a volatile liquid has been achieved considering the reactive wetting induced by surface adsorption of surface-active ionic liquid (SAIL) on the glass surface. 1-Tetradecyl-3-methylimidazolium bromide ([C₁₄mim]Br) in a volatile organic solvent, when placed on a total wetting glass, demonstrated various wetting regimes. The droplet of the methanolic solution of SAIL undergoes successive wetting stages (spreading-withdrawal, pinning and complete evaporation) after being cast onto the glass surface. During the first stage, the droplet expands due to contact-line instability, followed by contact line retraction and ultimately evaporation. This contact-line instability causes the droplet to split into smaller droplets. In contrast, in tetrahydrofuran (THF), the SAIL droplet exhibits self-propelled random motion without the need for any external force. Interestingly, this motion was tuned by the concentration of SAIL, droplets with lower concentration showed motion, whereas droplets with higher concentration exhibited pinning behaviour. Rim instability in methanol was observed, but was missing for THF. The driving mechanism behind the droplet behaviour in both solvents was reactive wetting, coupled with a differential surface tension, and evaporation rate owing to the vapour pressure difference. The solvent loss-induced surface-tension gradient (Marangoni stress), hysteresis-free surface and rapid SAIL adsorption cause distinct wetting. Additionally, parameters such as droplet trajectories, wetting area, and droplet speed were determined to analyse the wetting instability of the volatile liquids. This work can be utilised for motion-induced liquid transport to reactive wetting for sensing.

关键词： XPS   Vinyl   Imidazolium   it-electrons delocalisation  

摘要： In this study, three 1-octyl-3-vinylimidazolium ionic liquids are analysed by X-ray photoelectron spectroscopy. The C 1s fitting model is modified based upon the established one for 1-alkyl-3-methylimidazolium ionic liquids, taking into account the extra unsaturated substituent. The shake-up reduction is calculated. The impact of the π-electrons delocalisation on the electronic environment of the cation and the anion is illustrated, by comparing vinylimidazolium and ethylimidazolium, within three anion families. The π-electrons delocalisation across more atoms makes the cationic nitrogen centre being more positively charged, and thus showing larger binding energy. From another point of view, due to the π-electrons delocalisation across more atoms, the vinylimidazolium cation becomes more acidic, which enhances the cation-anion interactions, causing the more intense charge compensation from the anion to the cation and the subsequent increase of binding energies for anionic components. It concludes that the maximum binding energy shift of the anionic components is proportional to the anion basicity.

关键词： Multicomponent reaction   Optimization   Cytotoxicity   Molecular docking   ADMET analysis  

摘要： Cervix carcinoma is the most prevalent conditions affecting women globally. Due to the deadly nature of cancer cells, many strategies have failed to prevent their invasion and spread to nearby tissues. Pyrimidine derivatives have attracted considerable research interest owing to their versatile scaffold and significant medicinal importance. Pyrimidine-based analogues have made substantial contributions to the field of medicinal chemistry. Newly synthesized pyridopyrimidine compounds were tested for their cytotoxic effects on the cervical cancer cell line (SiHa). The results were compared with the help of computational information obtained from the computer-assisted software and ADMET Lab 2.0 web tool. The results of ADMET analysis showed that the synthesized compounds followed Lipinski's criteria. The compound 4c has the highest activity (IC₅₀ = 100 µM) among the synthesized compounds, which had the p-substituted -OCH₃ group. According to the structure-activity relationship (SAR), aryl ring substitutions are found to be crucial in determining inhibitory efficacy. In light of this, compound 4c may be regarded as a promising compound against SiHa cell line.

关键词： 干细胞治疗   牙周膜干细胞   胶原三螺旋重复蛋白1(CTHRC1)   细胞增殖   成骨分化   细胞外调节蛋白激酶1/2(ERK1/2)  

摘要： 背景:胶原三螺旋重复蛋白1是骨形成的正向调节因子,但是其在牙周膜干细胞中的作用及机制尚未明确。目的:探讨胶原三螺旋重复蛋白1对人牙周膜干细胞增殖、成骨分化的影响及作用机制。方法:体外分离培养人牙周膜干细胞,用过表达胶原三螺旋重复蛋白1慢病毒载体转染细胞,通过CCK-8法和流式细胞术检测过表达胶原三螺旋重复蛋白1对牙周膜干细胞增殖活性的影响;通过碱性磷酸酶活性、茜素红染色检测过表达胶原三螺旋重复蛋白1对牙周膜干细胞成骨分化能力的影响;采用Western blot检测过表达胶原三螺旋重复蛋白1后细胞外调节蛋白激酶1/2、磷酸化细胞外调节蛋白激酶1/2蛋白表达;采用Western blot和qRT-PCR检测阻断细胞外调节蛋白激酶1/2信号通路后,过表达胶原三螺旋重复蛋白1对牙周膜干细胞成骨分化相关因子Runt相关转录因子2、骨钙素、Osterix表达的影响。结果与结论:(1)CCK-8和流式细胞术结果显示,过表达胶原三螺旋重复蛋白1能够促进牙周膜干细胞增殖;(2)碱性磷酸酶活性、茜素红染色显示,过表达胶原三螺旋重复蛋白1能够促进牙周膜干细胞的成骨分化;(3)Western blot结果显示,过表达胶原三螺旋重复蛋白1激活了细胞外调节蛋白激酶1/2信号通路;(4)Western blot和qRT-PCR结果显示,过表达胶原三螺旋重复蛋白1促进了Runt相关转录因子2、骨钙素、Osterix蛋白和mRNA的表达,当使用细胞外调节蛋白激酶信号通路特异性抑制剂PD98059抑制信号通路激活后,成骨相关因子表达上调出现了一定程度的抑制。以上结果提示:过表达胶原三螺旋重复蛋白1可以促进牙周膜干细胞的增殖和成骨分化,其促成骨分化作用可能与细胞外调节蛋白激酶1/2信号通路的激活有关。