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关键词： Fiber reinforced plastics  

摘要： To analyze the dynamic performance of variable-angle ply porous fiber-reinforced sandwich composite panels under simply supported boundary conditions, the vibration differential equations for the porous double-layer sandwich panels were established based on the layerwise theory and the Rayleigh-Ritz method. These equations were subsequently solved using the Navier method. The dynamic characteristics at various ply angles were analyzed using Abaqus and the modal tests were performed with [0°/90°] and [±45°] ply orientations to validate the accuracy of the theoretical model. A parametric analysis of the porous double-layer sandwich panel was conducted using the theoretical model, followed by structural optimization using a genetic algorithm. The research reveals that laminated panels with a porosity of 94.854% and fiber ply angles in multiples of 45° exhibit outstanding dynamic performance. These results provide a reference for the design and manufacture of such structures. © 2025 Chinese Vibration Engineering Society. All rights reserved.

关键词： 磷酸盐   锰基材料   吸附   饮用水   废水处理  

摘要： 富营养化是一个全球性问题，威胁着饮用水安全乃至整个生态系统平衡。水体中磷（以磷酸盐为主）的过量排放是引起富营养化的重要原因之一，控制水体中磷的浓度，特别是磷酸盐浓度，具有重要意义。锰基材料具有良好的磷酸盐去除潜力，但目前缺乏对其系统性的归纳，是一种没有得到重视的金属基材料。对锰基材料在磷酸盐去除领域的研究已经从单一的锰氧化物发展到混合金属氧化物和氢氧化物、金属-载体复合材料和层状双金属氢氧化物等，同时，电辅助吸附法、等离子体法等新兴方法的出现进一步强化了锰基材料去除磷酸盐的能力。综述了不同锰基材料去除磷酸盐的效果与机理，并对不同锰基材料去除磷酸盐的应用前景进行了评述；从提高pHpzc或加强静电效应的角度，分析总结了强化锰基材料去除磷酸盐的方法；基于现有研究内容，提出了现有研究的不足之处及未来的发展方向，以期为锰基材料去除磷酸盐的研究提供参考。

关键词： Seismic design  

摘要： The substation switchgear is critical equipment in power systems. Traditional seismic vulnerability analysis only considers the structural failure of equipment, neglecting associated functional failure mechanisms. In order to account for structure-function related failure modes, a vulnerability assessment framework for switchgear was established to generate simulated seismic responses based on the optimized Copula function. Taking the 800 kV isolating switch as an example, a simulation model was developed based on test data to obtain original seismic response samples. This model was used to fit the marginal distribution function and build a Copula function to generate a large number of simulated response data to evaluate the structure-function joint failure probabilities. The results show that the simulated data generated by this framework can effectively reflect the correlation of the original samples;ignoring functional failure modes can underestimate the actual failure probability by up to 50%;at the current manufacturing level, it is difficult to significantly improve equipment reliability through material strength alone. Based on this framework, the design acceptance criteria for equipment strength and functional indicators can be effectively determined. © 2025 Chinese Vibration Engineering Society. All rights reserved.

关键词： 浮式悬索桥   行车荷载   张力腿基础   设计参数   动力响应特性  

摘要： 以张力腿平台为基础的大跨度浮式悬索桥建设方案在高水深、软土质的环境中具有较好的应用前景。由于其基础刚度较弱，行车荷载可能会引发桥梁的剧烈振动，可以通过张力腿基础设计参数的调整削弱其影响，但目前对行车荷载作用下该新型大跨度浮式桥梁的研究较少，此类方案可行性与适用性亟需得到验证。利用有限元软件计算行车荷载作用下的大跨度浮式悬索桥模型响应，改变基础浮箱淹没深度、拉索倾角，采用模态分析方法研究在行车荷载作用下张力腿基础设计参数变化对结构响应的影响。结果表明：大跨度浮式悬索桥的淹没深度、拉索倾角参数调整主要改变前两阶振型，且对横向响应影响较大；加大浮式基础的淹没深度、增加倾斜布置的张力腿拉索均能有效减小其在行车荷载作用下的振动，其中，对拉索倾角在何种角度可以使行车荷载作用下的浮桥响应达到最小，则需要通过具体分析得出；在设计阶段需尽可能详尽考虑相关张力腿基础设计参数，以增加整个浮桥方案在行车荷载作用下的应用可行性与适用性。

摘要： To obtain alkaline protease with enhanced thermal stability and catalytic activity, this study focused on the alkaline protease AprEbl derived from Bacillus licheniformis B66. Using molecular dynamic simulations, residues N183, G186, S265, S267, and Y320 in AprEbl were identified as highly flexible regions. Computer-aided design was employed to propose mutation sites, and five single-point mutant enzymes were generated using site-directed mutagenesis. Their enzymatic properties were subsequently investigated. Two advantageous mutants were selected for a second round of combinatorial mutagenesis. The results demonstrated that the double mutant S265H/S267F exhibited significantly improved thermal stability compared with the wild-type enzyme, although their specific activities were on par with each other. The half-life of this mutant increased by 7.35-fold at 55 ℃ and 5.01-fold at 75 ℃. Other single-point mutants also displayed better high-temperature tolerance than the original enzyme. This study provides a theoretical foundation for improving the enzymatic properties of alkaline proteases via protein engineering to meet industrial demands. © 2025 Chinese Chamber of Commerce. All rights reserved.

关键词： Fourier transform infrared spectroscopy  

摘要： To enhance the functional properties of potato proteins (PP), this study investigated the effect of different ultrasonic treatments (at 0, 200, 300, 400, 500, and 600 W for 20 min) combined with pH shift on modifying the functional and structural properties of PP. Changes in the functional and structural properties of PP after modification were examined in terms of solubility, emulsifying and foaming properties, particle size, ζ-potential, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns, Fourier transform infrared spectra (FTIR), fluorescence spectra, free sulfhydryl content, and surface hydrophobicity, and the correlation between functional and structural properties was analyzed. The results showed that the solubility of PP increased from 24.84% to 90.74% after pH shift to pH 12 in combination with 500 W ultrasonic treatment. Moreover, the emulsifying activity index (EAI) was enhanced by 86.37%, and the foaming capacity (FA) by 31.24%. Additionally, notable alterations in the molecular structure were observed accompanied by a decrease in the average particle size from 452.05 to 89.63 nm and a reduction in the ζ-potential value from −24.64 to −32.57 mV. The secondary structure analysis showed that the α-helix content decreased while the β-sheet content increased. The free sulfhydryl content and surface hydrophobicity significantly rose (P © 2025 Chinese Chamber of Commerce. All rights reserved.