Aeromonas hydrophila (A. hydrophila) is a highly harmful pathogenic bacterium in aquaculture, and its increasingly severe drug resistance poses a threat to global aquaculture and food safety. It is an urgent need to develop new antibacterial agents. Terpinen-4-ol is a natural plant monomer with broad-spectrum antibacterial activity, but its effect and mechanism against A. hydrophila remain unclear. In this study, the minimum inhibitory concentration (MIC) of terpinen-4-ol against A. hydrophila was 7.56 mM (1.17 mg/mL), at which it effectively inhibited bacterial growth. Scanning electron microscopy (SEM) revealed morphological changes in treated A. hydrophila, including cell shrinkage, deformation, and flagellar detachment or loss. Detection of nucleic acid, protein, alkaline phosphatase (ALP), and β-galactosidase leakage, together with propidium iodide (PI) staining, showed that terpinen-4-ol caused intracellular content leakage and increased PI fluorescence intensity. Measurements of succinate dehydrogenase (SDH) activity and reactive oxygen species (ROS) levels revealed that terpinen-4-ol at 1 MIC reduced SDH activity by 55.7
GH4169 nickel-based superalloy exhibits excellent mechanical properties and has aroused wide interests in applications of aerospace engine components and transmission systems. Currently, Conventional grinding (CG)of GH4169 generates excessive heat, resulting in high grinding temperatures that can easily cause grinding burns. Ultrasonic vibration assisted grinding (UVAG)an advanced hybrid processing technology, enhances heat dissipation through the periodic variation in abrasive grain motion. It is considered an ideal method for reducing grinding temperature. However, the complex and intermittent contact between the UVAG workpiece and abrasive grains presents an essential challenge for accurate theoretical temperature prediction. To address this issue, the grinding temperature prediction model for UVAG was developed according to the Welch-Type (WT) heat source. On this basis, we performed grinding experiments for comparing temperature prediction accuracy of WT heat source with that of the conventional rectangular heat source model. According to our findings, WT heat source exhibits the maximum prediction error of 23.2
The hole expansion strengthening is a pivotal technology for enhancing the performance of hole structures. The structural design of the mandrel plays a crucial role in determining the effectiveness of expansion strengthening and the subsequent fatigue performance of the hole structure. To explore the impact of the mandrel structure on hole expansion strengthening, a 3D finite element simulation model was established to analyze the hole expansion processes for both solid mandrel and split mandrel. Additionally, a series of hole expansion strengthening experiments were carried out, along with fatigue performance tests on specimens with holes, to investigate the influence of plastic deformation on the fatigue performance. The research results show that the maximum relative error range between the simulated residual stress values on the hole wall and the experimental data ranges from 5.3
This study reports the synthesis of the metal-organic framework MIL-101(Fe) via a solvothermal method, it integration with Fe3O4 particles, and subsequent modification with a covalent organic frameworks (COFs) to form Fe3O4@Fe-MOF@COFs. The composite was characterized through FTIR, XRD, TGA, SEM, BET, VSM, and XPS techniques, with a saturation magnetization of 30.31 emu/g. The effects of initial As(V) concentration, pH, temperature, adsorbent dosage, and contact time on adsorption were systematically investigated. Fe3O4@Fe-MOF@COFs exhibited exceptional adsorption capacity, achieving maximum uptake at pH 5. Kinetic analysis indicated that As(V) adsorption followed a pseudo-second-order model, suggesting chemisorption as the primary mechanism. The adsorption isotherm fit the Langmuir model, confirming monolayer adsorption with a maximum capacity of 283 mg/g. Thermodynamic analysis revealed that the adsorption process is spontaneous and exothermic. The material demonstrated strong resistance to interference from coexisting salts and could be efficiently recovered from the liquid phase, retaining approximately 91.6 % of its capacity after 10 cycles. Mechanistic studies using FTIR and XPS spectra before and after adsorption indicated that As(V) adsorption involves both coordination and electrostatic interactions. This work presents an effective strategy for developing high-performance adsorbents for the removal of As(V) from water.
To enhance the anti-friction and anti-wear performance of 100Cr6 bearing steel balls, a synergistic anti-friction strategy integrating laser texturing, solid lubricating particle filling and ball milling strengthening had been proposed. By constructing biomimetic texture structures of different scales, filling them with PTFE/MoS2/Al2O3 composite solid particles, then implementing ball milling strengthening, the lubrication function and mechanical properties were enhanced synergically. The results showed that the composite treatment significantly increased the hardness of the surface layer of the sample, while effectively inducing higher residual compressive stress, promoting grain refinement, and thereby significantly enhancing the material's resistance to plastic deformation, effectively verifying the coupling mechanism of "laser texture-lubricated particles-ball milling strengthening" in stress guidance and film formation excitation.
