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关键词： Luminescent metal-organic skeleton   Crystal structure   Fluorescence detection  

摘要： In this paper, the new ligand 1-(3,5-dicarboxybenzyl)-1,2,4-1H-triazole (H₂L2) is synthesized through in situ decarboxylation during solvothermal synthesis, using 1-(3,5-dicarboxybenzyl)-1,2,4-1H-triazole-3-carboxylic acid (H₃L1) as the feedstock ligand. Additionally, two new luminescent metal-organic framework (LMOF) materials are constructed: [Zn(L2)(H₂O)]·0.5H₂O (1) and [Cd(L2)(H₂O)] (2). These materials are subsequently characterized using various techniques, including single-crystal X-ray diffraction, infrared spectroscopy, powder X-ray diffraction, and thermogravimetric analysis. Single-crystal X-ray diffraction reveals that complex 1 forms a two-dimensional framework characterized by a " honeycomb "-like structure, represented by the topological symbol hcb. Complex 2 exhibits a "binuclear cluster" structure, denoted by the topological symbol flu-3.6. Fluorescence sensing experiments demonstrated that both complexes selectively detected Cr₂O₇^2- and CrO₄^2- in anion sensing assays, achieving detection limits of 0.21 µM and 0.11 µM for complex 1, and 4.83 µM and 0.56 µM for complex 2, respectively, while exhibiting strong immunity to interference. In contrast, cation detection experiments revealed that the two complexes specifically recognized Fe³⁺ and Ag⁺, with detection limits of 0.94 µM and 0.50 µM for complex 1, and 6.83 µM and 0.69 µM for complex 2, respectively. Based on this foundation, the detection mechanism was explored through additional experiments and density-functional theory calculations. It was found that the fluorescence quenching of the two LMOFs induced by Cr₂O₇^2-, CrO₄^2-, and Fe³⁺ primarily results from the internal

关键词： Charge transfer  

摘要： A pharmacophore hybridization approach was employed to design and synthesize a novel series of 1,3,4-oxadiazole-linked quinoline–rhodanine hybrids as potential dual inhibitors of α-amylase and α-glucosidase. The target compounds were prepared via cyclization of quinoline–rhodanine intermediates with substituted benzoic acids using phosphorus oxychloride under reflux conditions and were characterized by ¹H NMR, ¹³C NMR, and HR-MS analyses. Biological evaluation revealed significant inhibitory activity compared with acarbose (IC₅₀ = 3.62 μM for α-amylase and 4.12 μM for α-glucosidase). Nitro- and bromo‑substituted derivatives exhibited the most potent α-glucosidase inhibition (IC₅₀ = 2.82 and 1.96 μM), whereas the para-methyl analogue showed the strongest α-amylase inhibition (IC₅₀ = 4.96 μM). Structure-activity relationship analysis demonstrated that para electron-withdrawing substituents enhance enzyme inhibition. Compound 11d increased the apparent Km concentration-dependently without significantly affecting Vmax, indicating a competitive mode of inhibition, similar to acarbose. Molecular docking and 150 ns molecular dynamics simulations confirmed stable binding within the catalytic pockets, particularly for compound 11b in the α-amylase (1B2Y) system, supported by persistent hydrophobic and hydrogen-bonding interactions with key active-site residues. In contrast, weaker stabilization was observed in the α-glucosidase (5NN8) complex. Density functional theory calculations of selected derivatives (11b and 11d) revealed moderate HOMO-LUMO gaps (∼3.4 eV) and favorable global reactivity descriptors, supporting their stability and charge-transfer capability.

关键词： Benzo(a)pyrene   Cadmium   Iron sulfide   Kaolinite   Peroxymonosulfate   Stabilization  

摘要： The coexistence of heavy metals and organic contaminants in wastewater poses severe risks to public health and environmental sustainability. Iron sulfide (FeS) has attracted widespread attention for its potential in addressing such complex pollution, but suffers from the tendency to agglomerate and instability, which may lead to unsatisfactory remediation efficiencies. Herein, a novel Fe_1-xS/kaolinite composite (Fe_1-xS@K), derived from the transformation of FeS/kaolinite (FeS@K) material in an acidic condition, demonstrates efficient simultaneous removal of Cd(II) and benzo(a)pyrene (B[a]P) by ensuring excellent dispersion and stability. Notably, the 0.6-Fe_1-xS@K/peroxymonosulfate (PMS) system removed 96.9% of Cd²⁺ and 98.9% of B[a]P within 20 min, respectively. Mechanism analysis revealed that kaolinite modulates the particle size of Fe_1-xS to effectively minimize the agglomeration, thereby facilitating the activation of PMS and enhancing both thermal and chemical stability. This significantly boosts the generation of reactive oxygen species (ROS), e.g., SO₄^⋅−, ^⋅OH, ¹O₂, and ^⋅O₂⁻ in the degradation system, thus exhibits an exceptional potential for natural water and wastewater treatment due to its broad resistance to environmental interference. This work exemplifies a highly efficient sulfate radical-based advanced oxidation process for the removal of complex contaminants in water treatment.

关键词： CO2 reduction   Lanthanum-doping   Metal-organic frameworks   Methane   Oxidation state of Cu  

摘要： During the electrocatalytic CO₂ reduction (ECO₂R) process, the active oxidation states of Cu-based catalysts (e.g., Cu⁺) are unstable and prone to reduction to metallic Cu (Cu⁰), leading to decreased product selectivity and catalyst stability. To address this issue, this study proposed a catalyst design strategy involving lanthanum (La) doping to stabilize Cu oxidation states. Using typical Cu₃(BTC)₂ (HKUST-1) as a precursor, a series of x La/HKUST-1 materials with varying La doping levels were synthesized via a wet-chemical method, followed by electrochemical activation to obtain A-x La/HKUST-1 derived catalysts. Characterization revealed that appropriate La doping (Cu:La = 8:1) effectively modulated the electronic structure around Cu, suppressing its excessive reduction during the reaction and promoting the formation and stabilization of active Cu⁺ sites. Electrochemical performance tests in an H-cell demonstrated that A-0.1 La/HKUST-1 achieved a CH₄ Faradaic efficiency (FE_CH4) of 60.81% with a corresponding partial current density of −25.93 mA·cm⁻² at −1.37 V (vs. reversible hydrogen electrode (RHE)), significantly outperforming other catalysts. Furthermore, this catalyst exhibited excellent stability during a 24-h continuous test, maintaining an FE_CH4 above 55%. This research provides a novel material design concept and mechanistic insight for enhancing the CO₂ methanation pathway by stabilizing Cu oxidation states via rare-earth La doping.

关键词： Flame stability   Jet A-1   NOx emission   Oxygenated biofuels   Spray characteristics   Sustainable Aviation Fuels (SAFs)  

摘要： Bio-derived fuels have long been used in IC engines, due to their low carbon and potential for production from sustainable sources. In recent years, there has been growing interest in using biofuels in gas turbines, particularly in the aviation sector. However, biofuels have different physicochemical properties than traditional jet fuels, which may lead to variations in energy density, combustion characteristics, and thermal stability. Thus, this study aims to shed light on how variations in the physical and chemical properties of sustainable biofuels, including their higher oxygen content, affect combustion performance, particularly when used as a blend with conventional fuels as a sustainable alternative. Here, the combustion performance of aviation Jet A-1 and its blends with 20% and 50% (by volume) of five different oxygenated biofuels (e.g., ethanol, acetone, butyl butyrate, iso-pentanol, and butanol), selected to test a wide range of properties, is experimentally investigated in a swirl-stabilized gas turbine combustor. Flame morphology, lean blow-off (LBO), exhaust temperature, and emissions measurement are carried out to compare the performance of the various tested blends relative to neat Jet A-1. The flame morphology, exhaust temperature, and emissions are tested at two equivalence ratios of 0.55 and 0.7. The results show that most blends have better LBO performance than Jet A-1, with maximum enhancements of 11%, 13%, and 15% at 50% blends of butyl butyrate, iso-pentanol, and butanol, respectively. The predicted (not measured) Sauter mean diameter (SMD), by the Lefebvre equation, and oxygen content closely explain the LBO trends. The blends exhibit a notable reduction in NOx emissions compared to neat Jet A-1, particularly for the biofuels, which have lower exhaust temperatures and smaller SMDs, resulting in maximum decreases of 60%, 72%, and 50% for 50% blends of ethanol, acetone, and butyl butyrate, respectively. This study demonstrates

关键词： 1,2,3-triazole   Anti-metastatic activity   Apoptosis   EGFR inhibition   Isoxazole   Lung cancer   Molecular docking  

摘要： Lung cancer remains one of the leading causes of cancer-related mortality worldwide, and dysregulation of the epidermal growth factor receptor (EGFR) signaling pathway plays a central role in its progression. In the present study, a novel series of fused isoxazole and fused 1,2,3-triazole derivatives (4a–4 h and 5a–5 h) were rationally designed, synthesized and evaluated for their anticancer potential against human lung cancer cells. These compounds were synthesized via a single-step [3 + 2] cycloaddition reaction using (Z)-1-(4-fluorophenyl)-N-(4-iodobut-3-yn-2-ylidene)-3-methyl-1H-pyrazol-5-amine as the key precursor. In silico molecular docking studies revealed strong and stable interactions of the synthesized compounds with the ATP-binding pocket of the EGFR kinase domain, comparable to that of the reference drug, erlotinib. In vitro EGFR kinase inhibition assays confirmed the ability of the lead compounds to suppress kinase activity. Cytotoxicity studies on non-cancerous cell lines (HBEC30KT and HEK293) demonstrated minimal toxicity and a favorable therapeutic *** contrast, selected compounds, particularly 4 h, 5d and 5 h, exhibited potent antiproliferative activity in lung cancer cell lines H1975 and A549, with a marked reduction in cell viability and growth. Flow cytometric analysis revealed significant cell cycle arrest in the Sub-G1 phase, accompanied by induction of apoptosis as confirmed by Annexin V-FITC staining. Furthermore, Transwell migration and soft agar colony formation assays demonstrated a strong inhibitory effect on cancer cell migration and anchorage-independent growth, indicating effective suppression of metastatic and tumorigenic potential. In silico Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) analysis predicted favorable pharmacokinetic and safety profiles for the lead ***, the results suggest that fused isoxazole and fused 1,2,3-triazole derivatives, especially compounds 4 h, 5d a

关键词： Bidirectional HCR   Cell extracts   CRISPR/Cas12a cascade   Detection   PARP1  

摘要： This study presents a bidirectional hybridization chain reaction (HCR)-activated CRISPR/Cas12a cascade for the sensitive detection of human poly(ADP-ribose) polymerase 1 (PARP1). A double-stranded probe (dsRP) was specifically engineered with two pendant triggers at both termini to facilitate PARP1 recognition and to initiate the HCR. Upon exposure to PARP1, the dsRP activates the enzyme, leading to the synthesis of a long, branched poly(ADP-ribose) (PAR) polymer. After capture and magnetic separation, the reacted dsRP is isolated together with the PAR polymer. Subsequently, the addition of hairpin structures triggers simultaneous HCR processes from the pendant triggers at both ends of the dsRP, thereby establishing a bidirectional HCR. Thereafter, complexes of Cas12a protein and CRISPR RNA (crRNA) specifically recognize the repeated double-stranded DNA (dsDNA) sequences within the HCR products, generating multiple sequential ternary complexes. These activated CRISPR/Cas12a systems function as a cascade to cleave the reporter molecule, resulting in an enhanced fluorescence signal. The sensitive detection of PARP1 was achieved through the two-stage amplification strategy involving bidirectional HCR and CRISPR/Cas12a cascade, resulting in a limit of detection (LOD) of 2.5 × 10⁻⁵ U/mL with satisfactory specificity, precision, and accuracy. Furthermore, inhibitor assays were conducted using two oncotherapeutic drugs, and PARP1 quantification was successfully performed in various cancer cell extracts. Collectively, this study introduces a novel bidirectional HCR strategy for CRISPR/Cas12a activation and presents a sensitive approach for PARP1 detection, which holds considerable promise for cancer diagnosis, inhibitor screening, and drug discovery.

关键词： CO2 utilization   CO2 cycloaddition   Propylene carbonate   Zeolite   Synergistic catalysis  

摘要： Converting CO₂ and propylene oxide (PO) to produce propylene carbonate is of great importance for industry due to the mild reaction condition, high atomic efficiency and high economic values. The ring-opening process of propylene oxide is considered as the key to improve the reaction performance. Herein, a Zn/S-1 catalyst was constructed with a controlled number of interfacial Lewis acid sites and silanol groups by incorporation of various amounts of Zn. An increased number of Lewis acid sites and a decreased number of silanol groups were found with the increasing of Zn loading. Propylene oxide conversion (∼88.77%) and high selectivity of propylene carbonate (>99%) were obtained after 6 h of reaction under 120 °C, which is much higher than the widely used ZnBr₂ catalyst (propylene oxide conversion of 56%–67%). Additionally, the halogen ion content employed in this study is notably low, amounting to only 0.008 mol_{halogen ions}/mol_PO. Moreover, the synergistic catalysis between Lewis acid sites and silanol groups was demonstrated with enhanced ring-opening capability of propylene oxide. It was found that the 3 wt% Zn/S-1 with 0.22 mmol/g Lewis acid sites and appropriate amount of silanol groups can effectively activate the C–O bond in propylene oxide, which eventually resulted in the improved catalytic performance. This work establishes design principles for efficient CO₂ cycloaddition catalysts and elucidates the synergy of Lewis acid sites with silanol functionalities.

关键词： Cannabinoid receptor 1   Glutamatergic neurons   Ischemic stroke   Neuroprotective  

摘要： Cannabinoid receptor 1 (CB1R) is widely expressed in the brain and implicated in protection against ischemic stroke, yet its cell-type-specific functions remain incompletely understood. To systematically dissect the contributions of excitatory and inhibitory CB1R populations under ischemia, we generated mice with conditional CB1R knockout in glutamatergic (CB1R^Glut−KO) or GABAergic (CB1R^GABA−KO) neurons, alongside global CB1R deletion, and subjected those mice to permanent focal cerebral ischemia. Ischemic injury was evaluated using infarct volume quantification, histological staining, and neurological behavioral tests. Glutamate dynamics in the ischemic region were monitored using a fluorescent reporter iGluSnFR. The role of Glut-CB1R in synaptic transmission and anoxic depolarization was assessed via electrophysiological recordings under both baseline and ischemic conditions. We found that CB1R^Glut−KO mice fully recapitulated the exacerbated ischemic injury and neurological impairment seen in global knockouts, whereas CB1R^GABA−KO mice showed no significant phenotype. This functional non-redundancy was attributed to a Glut-CB1R-specific brake on excitotoxicity, as its loss elevated extracellular glutamate after ischemia. Pharmacological inhibition of glutamate N-methyl-D-aspartic acid (NMDA) receptors attenuated the exacerbated neurological deficits in CB1R^Glut−KO mice. Electrophysiological recordings revealed enhanced spontaneous excitatory synaptic transmission and accelerated anoxic depolarization in CB1R^Glut−KO pyramidal neurons under ischemic conditions. Pharmacological inhibition of endocannabinoid degradation conferred protection against ischemic injury in control mice but failed in CB1R^Glut−KO mice, confirming that Glut-CB1R is the obligate mediator of this protection. These findings demonstrate that CB1R-mediated neuroprotection in acute, non-preconditioned ischemia is uniquely de

关键词： hollow H-ZSM-5   Propane-dehydrogenation-aromatization   PtIn@Silicalite-1   Tandem catalyst  

摘要： Propane-dehydrogenation-aromatization (PDA) has significant potential for industrial applications; however, the traditional reported catalyst systems suffered from rapid deactivation and low aromatics selectivity. Herein, a PtIn@Silicalite-1 (PtIn@S-1) || hollow H-ZSM-5 composite with dual-bed configuration was constructed and it delievered an unpresencent catalytic lifetime of 1300 h with propane conversion and aromatics selectivity of 78% and 64%, respectively. Multiple characterizations and theoretical calculations indicate that propane is first dehydrogenated on PtIn@S-1 to propene, which diffuses onto the acid sites of hollow H-ZSM-5 to produce aromatics through aromatization. Construction of tandem catalyst by introducing aromatization moiety can break the thermodyanmic limitations of propane dehydrogenation and improve the thermodynamic equilibrium conversion. Besides, introducing additional dehydrogenation sites significantly increases the concentration of olefin intermediates, thereby facilitating rapid aromatization at the acid sites. Meanwhile, it also reduces the contact between alkanes and the acid sites, avoiding undesired cracking reaction. The aromatics selectivity and yield can be further elevated to 78% and 70% through introducing Ga species into hollow H-ZSM-5. This work provides a new strategy for the design of highly efficient tandem catalysts for propane dehydrogenation and aromatization.