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摘要： In this study, we report the synthesis, characterization, and enzyme inhibition effects of new thiosemicarbazone-indole-1,2,3-triazole-acetamide derivatives. All compounds were characterized by using NMR and FTIR spectroscopic and elemental analysis techniques. All new thiosemicarbazone-indole-1,2,3-triazole-acetamide derivatives (12a-q) were examined as potential inhibitors against acetylcholinesterase (AChE) and two key human carbonic anhydrases (hCA I and II), which are important in the treatment of Alzheimer’s disease. Enzymatic evaluations showed that all new compounds were more potent than the standard inhibitor tacrine against AChE, and most were more potent than the standard drug acetazolamide against carbonic anhydrases. Specifically, the best compound against AChE (12f) was 93.2-fold more potent than tacrine, while the best compounds against hCA I (12l) and hCA II (12m) were 2.4-fold and 2.3-fold more potent than acetazolamide, respectively. By molecular modeling study, compounds 12f, 12l, and 12m were placed into the active sites of AChE, hCA I, and hCAII, and the docking data agreed with the in vitro findings. Furthermore, molecular dynamics simulations demonstrated that compound 12f formed a stable complex with AChE.

摘要： A bulk single crystal of organic 2,6-dimethylpyridinium 4-nitrobenzoate (DMP4NB) was successfully grown at room temperature using slow evaporation solution growth technique (SEST). Single-crystal X-ray diffraction (SXRD) analysis revealed that crystal belongs to monoclinic crystal system with the P2₁/c space group. The molecular structure and presence of functional groups were confirmed by Fourier-transform infrared (FT-IR) spectroscopy. Optical studies carried out using UV–Vis–IR spectroscopy demonstrated high optical transparency of 91% in the visible region, with a lower cutoff wavelength of 384 nm and an estimated optical band gap of 3.00 eV. Photoluminescence (PL) measurements showed a prominent emission peak at 467 nm, confirming blue emission close to the ultraviolet cutoff region. Thermal analysis indicated that the crystal is thermally stable up to 110 °C. The laser damage threshold was evaluated using an Nd:YAG laser and was found to be 8.55 GW cm⁻², indicating good resistance to high-intensity laser irradiation. Frequency-dependent dielectric studies revealed a low dielectric constant and low dielectric loss at higher frequencies. The third-order nonlinear optical (NLO) properties were investigated using the Z-scan technique, highlighting the potential of DMP4NB single crystal for optoelectronic and photonic applications.

关键词： DFT   Dual fluorescent   Excited-state double proton transfer   Halogen substitution   Triazole derivatives  

摘要： This work uses DFT and TD-DFT to elucidate how the dual-proton fluorescent probe Br-3N-2Et detects esterase activity and explains the origin of its experimentally observed fluorescence emission. Furthermore, the influence of halogen substitution on the excited-state intramolecular proton transfer (ESIPT) process in 3N-OH triazole derivatives is investigated in depth. By analyzing the geometric structures, infrared (IR) vibrational spectra, interaction region indicator (IRI) distributions, and topological parameters of the target molecules and their derivatives in both the ground (S₀) and excited (S₁) states, it is demonstrated that the intramolecular double hydrogen bonding interactions are significantly strengthened upon photoexcitation. Combined analysis of frontier molecular orbitals (FMOs) and electron-hole distribution characteristics reveals that excited-state charge redistribution plays a crucial role in facilitating ESIPT and excited-state double proton transfer (ESDPT). Moreover, potential energy surface (PES) scans confirm the feasibility of a stepwise ESDPT mechanism in the S₁ state. Computational results indicate that concerted dual-proton transfer is energetically inaccessible in the 3N-OH system. Instead, only sequential single-proton transfers occur—while the first proton transfer (ESIPT-I) is favorable, the second (ESIPT-II) is kinetically hindered following the initial transfer. Notably, the experimentally reported emission maximum at 498 nm does not originate from the previously proposed ESDPT tautomer but can be unambiguously assigned to the Br-3N-OH-PT1 tautomeric form. This work further demonstrates that halogen substitution effectively modulates the ESDPT behavior of 3N-OH derivatives: electron-withdrawing groups such asCF₃ and

摘要： Membrane-based separation is a promising technology for CO₂ capture and gas purification due to its energy efficiency and scalability. Among these, mixed matrix membranes (MMMs) have garnered significant attention for surpassing the performance limits of neat polymers. This study investigates the mechanistic influence of azine-linked covalent organic framework (ACOF-1) incorporation on the gas transport behavior of Pebax-based mixed matrix membranes (MMMs) for CO₂/CH₄ separation. Pebax–ACOF-1 MMMs with varied filler loadings (2–10 wt%) were synthesized via solution casting and characterized using XRD, FTIR, SEM, TEM, and tensile testing. Structural and morphological analyses confirmed good compatibility and strong interfacial adhesion between ACOF-1 and the polymer matrix, minimizing the formation of non-selective voids. Mixed-gas permeation experiments were conducted at 1 bar and temperatures ranging from 24 to 70 °C. Results revealed that the addition of ACOF-1 significantly improved both CO₂ permeability and CO₂/CH₄ selectivity compared to pure Pebax. The optimal membrane, containing 5 wt% ACOF-1, exhibits a CO₂ permeability of 227.2 Barrer and a CO₂/CH₄ selectivity of 16.9 at 70 °C, about a three-fold improvement over the neat Pebax membrane. Time-lag measurements confirmed that the performance enhancement arises primarily from diffusivity gains rather than solubility changes due to formation of a Pebax/ACOF-1 interfacial region with enhanced diffusivity for CO₂ and CH₄. Excessive filler loading (10 wt%) led to aggregation, reducing both permeability and selectivity. These results establish a direct relationship between filler loading, free-volume modification, and diffusivity-controlled CO₂ transport, offering mechanistic insight critical for designing next-generation COF-based MMMs for gas separation.

关键词： Catalysts   film capacitor   poly (4-methyl-1-pentene)   polypropylene  

摘要： Under the trend of high-temperature development in power electronic devices, polymer-based film materials for commercial capacitors face a core bottleneck: when the operating temperature exceeds 85 degrees C, their performance degrades significantly, limiting their application under working conditions. Poly(4-methyl-pentene) (PMP), which has a dielectric constant similar to that of commercial capacitor base film materials, also boasts a high melting point (236 degrees C) and superior dielectric loss (less than 0.0001 at 1 MHz), showing great potential to break through the technical barriers of high-temperature capacitors. Despite its significant advantages in basic performance, PMP is constrained by ultra-thin film formation technology ( <10 mu m), high oxygen permeability, and complex synthesis processes, leading to delayed practical applications. This paper systematically reviews the synthesis techniques, crystal structure, dielectric properties, and application progress of PMP materials in capacitors. By integrating research on synthesis, structure, performance, and application, this study aims to provide theoretical support for material design, process optimization, and performance enhancement of PMP-based high-temperature capacitors, promoting their practical use in harsh environments.

关键词： Alpinia oxyphylla Miq   NF-κB/IκBα signaling pathway   TGF-β1/Smad signaling pathway   Zingiberaceae   anti-renal fibrosis activity   sesquiterpenoids  

摘要： Thirteen previously undescribed and structurally diverse sesquiterpenoids—comprising seven cadinane-type (1a, 1b, 2a, 2b, 3a, 3b, and 4), two eremophilane-type (8a and 8b), two eudesmane-type (9 and 10), one tricyclic (12), one guaiane-type (13), along with eight known analogues (5–7, 11, and 14–17) were isolated from the fruits of Alpinia oxyphylla. The structures of the thirteen sesquiterpenoids, including their relative and absolute configurations, were determined through their NMR, HRESIMS, and ECD spectroscopic data. Eight compounds (1b, 2a, 3a, 3b, 5, 8a, 8b, and 11) were found to have significant anti-renal fibrosis activity by inhibiting the expression of extracellular matrix components (Fibronectin and Collagen I) and α-SMA in TGF-β1 induced NRK-52e cells. Compounds 1b and 8b displayed significant inhibitory activity towards three markers of renal fibrosis in a dose-dependent manner in three types of TGF-β1 induced kidney cells (NRK-52e, NRK 49f, and HCK-8). RNA-seq analysis and target protein validation displayed that the anti-renal fibrosis activity of 1b was related to modulation of the NF-κB P65/IκBα signaling pathway, and simultaneously showed relative correlation to the inhibition of Smad3 phosphorylation. These results suggested that NF-κB P65/IκBα and TGF-β1/Smad3 signaling pathways were collectively mediated for the biological activity of 1b, revealin

关键词： Ba(Mg1/3Ta2/3)O3   CMAS corrosion behavior   Corrosion mechanism   Microstructural evolution   Thermal barrier coatings  

摘要： Calcium–magnesium-alumino-silicate (CMAS, CaO-MgO-Al₂O₃-SiO₂) corrosion poses a critical threat to the durability of thermal barrier coatings (TBCs) in high-temperature turbine environments. In this study, the CMAS corrosion behavior of plasma-sprayed Ba(Mg_1/3Ta_2/3)O₃ (BMT)-YSZ double-ceramic-layer coatings was investigated under varying temperatures and exposure durations. Cross-sectional microstructural characterization and phase analysis, combined with first-principles calculations, elucidate the evolution of reaction products and cation transport during corrosion. Molten CMAS initially infiltrates the porous coating through microcracks and reacts preferentially with highly diffusive Ba, forming Ba-rich reaction products. With increasing temperature and exposure time, CMAS infiltration is enhanced due to improved wettability, while Ta gradually participates in the interfacial reactions. Distinct corrosion features are observed at different stages, the corrosion mechanism correspondingly evolves from grain boundary attack to intragranular corrosion. Throughout the corrosion process, CMAS is progressively consumed via chemical reactions within the BMT layer, which effectively delays its further penetration and preserves the chemical integrity of the underlying YSZ layer under the tested conditions.

关键词： Elaeocarpus angustifolius   Larvicidal   Aedes aegyptii   Culex quinquefasciatus   Bioactive compounds   GCMS   9-Octadecenoic acid   1   2   3-Benzenetriol  

摘要： A number of illnesses, including malaria, chikungunya, dengue, yellow fever, Zika and dengue have been transmitted by mosquitoes. Initially, synthetic and chemical insecticides provided effective mosquito control. However, over time, mosquito species developed considerable resistance to these substances. Furthermore, the extensive application of these chemicals has caused environmental damage, health risks and pollution. Plant extracts could be an alternative source of mosquito control agents which are safe environmentally. The research is to examine different solvent extracts like Hexane, Chloroform, Ethyl acetate, Methanol and Ethanol fruit, leaf and stem extract of Elaeocarpus angustifolius against the mosquitos (Aedes aegyptii &Culex quinquefasciatus) larvicides. The chloroform and ethyl acetate extracts of fruit and methanol extract of leaf of E. angustifolius showed significant larvicidal activity against Ae. aegyptii with LC₅₀ values of 14.199, 28.743, 222.137 ppm respectively, whereas chloroform and ethyl acetate extracts of fruit and hexane extract of leaf showed significant larvicidal activity against Cx. quinquefasciatus with LC₅₀ values of 58.461, 94.857, 298.934 ppm respectively. The extract showing the highest activity was analysed using GC-MS which identified its primary bioactive molecules. The GC-MS (Agilent 8890) spectrum further revealed several compounds existing in the crude extracts of which 9-Octadecenoic acid known as Oleic Acid (70%) and 1,2,3- Benzenetriol (22%) was most important compounds. Hence, the research reveals that chloroform and ethyl acetate fruit crude extracts of Elaeocarpus angustifolius Blume are environmentally safe and an effective method of controlling vector mosquitoes.

关键词： 髓核细胞   腰椎间盘突出症   氧化应激   铁死亡   水凝胶   铁抑素1   生物材料  

摘要： 背景:针对铁死亡的分子机制,干预铁代谢或抑制脂质过氧化有望成为治疗腰椎间盘突出症的新策略,为疾病防治提供新的研究方向。目的:以聚乳酸-羟基乙酸共聚物-聚乙二醇-聚乳酸-羟基乙酸共聚物水凝胶作为载体,通过体外细胞实验和动物体内实验观察铁死亡抑制剂铁抑素1对腰椎间盘突出症的作用机制。方法:(1)将第3代小鼠髓核细胞分3组处理:对照组不进行任何处理,模型组添加10 ng/mL白细胞介素1β,铁抑素1组加入10 ng/mL白细胞介素1β+25μmol/L铁抑素1处理,检测细胞内丙二醛水平、谷胱甘肽水平、铁离子含量以及细胞外基质相关基因Ⅱ型胶原蛋白、聚集蛋白聚糖、基质金属蛋白酶3 mRNA表达。(2)制备负载铁抑素1的聚乳酸-羟基乙酸共聚物-聚乙二醇-聚乳酸-羟基乙酸共聚物水凝胶(载药水凝胶),表征水凝胶的微观形貌与体外药物释放情况。将80只C57BL/6小鼠随机分为正常组、模型组、游离药物组和载药水凝胶组,每组20只。除正常组外,其余3组建立L5/6腰椎间盘突出症模型,模型组、游离药物组和载药水凝胶组椎旁组织分别注射PBS、铁抑素1溶液、载药水凝胶,动态监测各组小鼠机械痛和热痛阈值。给药第7天提取髓核组织,检测炎症因子(肿瘤坏死因子α和白细胞介素1β)、丙二醛、谷胱甘肽水平以及铁死亡通路相关基因谷胱甘肽过氧化物酶4、溶质载体家族7成员11 mRNA表达。结果与结论:(1)与对照组相比,模型组细胞内丙二醛水平、细胞内铁离子聚集、基质金属蛋白酶3的mRNA表达均升高(P<0.05),谷胱甘肽水平及Ⅱ型胶原和聚集蛋白聚糖的mRNA表达减少(P<0.05);与模型组比较,铁抑素1组细胞内丙二醛水平、细胞内铁离子聚集、基质金属蛋白酶3的mRNA表达均降低(P<0.05),谷胱甘肽水平及Ⅱ型胶原和聚集蛋白聚糖的mRNA表达升高(P<0.05)。(2)扫描电镜下载药水凝胶呈现疏松多孔结构,内部含有大小不一的空泡,该水凝胶具有良好的药物缓释性能。与模型组相比,游离药物组和载药水凝胶组小鼠的疼痛均有缓解,炎症因子、丙二醛水平降低(P<0.05),谷胱甘肽水平与谷胱甘肽过氧化物酶4、溶质载体家族7成员11 mRNA表达均升高(P<0.05),并且载药水凝胶的作用强于游离药物。(3)结果表明,铁抑素1通过调节氧化应激和铁死亡相关基因表达发挥髓核细胞保护作用,治疗小鼠腰椎间盘突出症。

关键词： Bifunctional catalyst   Core–shell structure   Hydroformylation   Magnetic nanoparticles   One-step alcohol synthesis  

摘要： The purpose of the olefin hydroformylation-hydrogenation tandem reaction for alcohol synthesis is to design a highly efficient and stable heterogeneous catalyst. In this study, a novel heterogeneous magnetic nanoparticle-supported rhodium-cobalt bimetallic core–shell catalyst was prepared, which exhibits excellent synergistic catalytic performance and enables a one-step alcohol synthesis process. The magnetic support Fe₃O₄ allows for rapid separation of the catalyst from reaction products under an external magnetic field. The 7.5Co0.5Rh/Fe₃O₄@SiO₂ magnetic core–shell catalyst was successfully prepared by loading active metals via a one-pot impregnation method and performing silica coating using the Stöber method. It shows outstanding olefin conversion (99.71%) and alcohol selectivity (91.17%). The effect of preparation conditions, process conditions, and the universality of substrates were investigated in detail. The catalyst was reused 5 times, and the performance differences between the core–shell catalyst and the traditional impregnated catalyst with the same support, as well as the differences in metal leaching during the reaction, were compared. In addition, the catalyst could participate in the reaction directly without prior reduction, avoiding the additional costs associated with subsequent reduction steps.