Surface microtextures with negative Rsk values were prepared on the surface of nickel-aluminum bronze using femtosecond laser, and the influence of Rsk values on cavitation performance was studied. The results show that, under the condition of similar Ra values, the cavitation incubation period of the femtosecond laser prepared sample(Rsk-1.00) was extended from 59 minutes to 89 minutes, and the cumulative mass loss was reduced by about 38%. The incubation period of the nanosecond laser prepared sample(Rsk-0.04) was extended by 8 minutes, and the sandpaper polished sample(Rsk 1.05) was advanced by 6 minutes, with a cumulative weight loss reduction of about 17%. In addition, the cavitation morphology of the sample prepared with femtosecond laser is better than that of the other sample. This is because the negative Rsk values surface is mainly characterized by depressions. When bubbles pass over it, the external pressure increases, the stability of the bubbles is enhanced, and the bubbles are less likely to collapse. Additionally, the concave topography facilitates water retention and the formation of a water cushion, which can absorb the energy released during bubble implosion, thereby mitigating the cavitation damage to the material.

In order to simulate the space weightlessness environment and eliminate the friction between the large load space equipment and theenvironment, a pneumatic suspension platform suitable for the test of large load space equipment is proposed.The principle of cylinder suspension balance and pressure stabilization is analyzed, and the mathematical model and dynamic equation of cylinder balance lateral force are established.The side gas film pressure of the air bearing of the suspension platform main component is simulated.The optimal throttling parameters of the air bearing are obtained as follows: the throttling area is 0.3 mm2and the number of throttling holes is 8; the mechanical simulation of the air-floating piston is carried out by Solidworks, and it is determined that the air gap of 25 μm can avoid functional failure under the condition of maximum load fluctuation.Taking the 1.8 T specimen with large load as the test object, a pneumatic suspension test platform was built and relevant experimental research was carried out.The results show that when the compensation coefficient of the displacement compensation device is 1.7, the pressure fluctuation range is less than 91 Pa, which meets the test requirements. This study provides theoretical and technical support for the suspension test of large load space equipment.

Electrocatalytic hydrogen production has emerged as a pivotal strategy for harnessing green energy. This study systematically investigates the hydrogen precipitation performance of 17 metal single-atom catalysts(SACs) with diamond-supported vertical graphene nanoribbons(DS-VGNR) heterojunctions as carriers using first-principles calculations based on density functional theory(DFT). The results indicate that DS-VGNR heterojunctions can effectively stabilize most of the metal SACs, exhibiting excellent support properties. Analysis of hydrogen adsorption behavior reveals that when Co or Ru atoms are doped on DS-VGNR via double vacancy defects, their corresponding ΔGH*values for hydrogen absorption are 0.02 and-0.06 eV, respectively, indicating outstanding catalytic activity. Notably, Co-doped DS-VGNR shows great potential as a non-precious metal catalyst. The superior catalytic performance is attributed to its unique electronic structure properties, which includes effective charge transfer regulation optimization of the metal atom coordination environment, modulation of d-orbitals occupancy and adjustment of the d-band center position.

Reinforcement methods of masonry walls based on assembly and precast technology can effectively improve the compressive capacity of masonry walls. In order to investigate the compressive capacity of masonry walls reinforced with lightweight concrete wall panels, prefabricated lightweight concrete(AAC) wall panels were used to reinforce both sides and one side of an original masonry wall with special adhesives and pins. The mechanical properties of the original masonry wall and the reinforced masonry wall were analyzed using a nonlinear finite element software in order to investigate the connection mechanism, mechanical characteristics, and damage patterns between the precast lightweight concrete wall panels and the masonry wall. The analysis results showed that the combined wall formed by externally affixed precast lightweight wall panels has an effective restraining effect on the brick wall, which can significantly improve the compressive load-bearing performance of the brick wall. Compared with the original brick wall, the composite wall formed by double-sided reinforcement has the best effect, and its strength can increase by 1.27 times. When the thickness of the prefabricated wall is larger than or equal to 75 mm, the strength of the composite wall can be improved to a certain extent. When the thickness of the prefabricated wall is larger than or equal to 100 mm, the strength of the composite wall is as high as 37.1% of that formed by double-sided reinforcement. Based on the calculation formula for the axial bearing capacity of composite masonry members and by considering the characteristics and strain hysteresis of the lightweight concrete surface layer, a simplified calculation formula for the bending capacity of axial compression masonry members reinforced by prefabricated lightweight concrete surface layers is proposed.

In order to study the behavior of the welded joints with H-steel beams and circular hollow section(CHS) columns, one H-steel beam-middle CHS column joint specimen(referred to as middle column-beam joint) and one H-steel beam-CHS side column joint specimen(referred to as side column-beam joint) were tested. The test results show that the two specimens showed the same failure mode and both show elastoplastic buckling of the CHS column wall near the flange of the H-steel beam. The bearing-capacity of the two joints decreases slowly after the peak load, indicating that the joints shows good deformation ability. The plastic development of the joints is mainly concentrated in the CHS column wall near the H-steel beam. The flexural strength of the side column-beam joint is higher than that of the middle column-beam joint(higher than 16.5%). The formulae of CIDECT specification predict the flexural strength of the side column-beam joint well but underestimates the flexural strength of the middle column-beam joint, while the CECS specification is on the contrary. By contrast, EC3 specification conservatively predicts the strength of both two joints.

As traffic continues to increase, the construction of multi-level transportation systems has become a key initiative to optimize and enhance urban transportation functionality. To save space beneath elevated bridges, a large cantilever-Y-shaped pier system is increasingly used as the substructure of urban viaducts. Based on a practical expressway project in Jiaxing, Zhejiang Province, this paper designed Y-shaped pier specimens and conventional column pier specimens and used the ABAQUS software to establish finite element models for quasi-static seismic performance analysis. The failure modes and quasi-static indicators of the two types of specimens were compared. The results indicate that the Y-shaped pier predominantly fails in shear at the branches whereas the column pier exhibits flexural failure at around 0.75D(750 mm) from the pier base. Compared with the column pier with the same reinforcement ratio, the yield load, peak load, and ultimate load of the Y-shaped pier are reduced by 44.10%, 37.94%, and 38.37%, respectively. Although the Y-shaped pier has a lower load-bearing capacity, the higher volumetric stirrup ratio significantly improves the ductility coefficient compared with the column pier. However, the Y-shaped pier experiences rapid stiffness degradation due to localized shear failure, making its stiffness retention lower than that of the column pier. The residual displacements of the two types of piers show little difference. The residual deformation of the Y-shaped pier is concentrated in the shear failure zone while that of the column pier is primarily localized in the flexural zone at the pier base. These findings of this study provide a valuable reference for the application and optimization of large cantilever-Y-shaped pier systems.

Federated learning is a new machine learning paradigm designed to address the needs of distributed data storage and privacy protection, where clients collaboratively train a model. However, in practical applications, client data is often non-independent and identically distributed(Non-IID). Federated learning randomly selects a subset of clients for training in each round, and the sampled clients typically fail to fully represent the global data distribution. This exacerbates the impact of Non-IID on training, leading to inefficiencies in global model training and reduced accuracy. To address this issue, a clustering-based federated learning client sampling algorithm(FedCG) is proposed. The core idea of this method is to enhance the diversity of training data in each round, thereby improving the training efficiency and accuracy of the model. First, the “representative gradient” is used to calculate the inverse cosine similarity between clients. The similarity is applied for hierarchical clustering of the clients. Next, clients are grouped based on the clustering results. Finally, experiments are conducted on standard datasets such as Fashion-MNIST, CIFAR-10, EMNIST-Letters, and EMNIST-Balanced. Compared to three baseline algorithms: FedAvg, FedProx, and CSS,the accuracy of global model testing has significantly improved, with a maximum increase of 12%.

Superpixels are commonly employed in various computer vision tasks to improve computational efficiency and feature extraction capabilities to address the issue of boundary leakage caused by the grid-based initialization strategy in existing seed-initiated superpixel methods, a seed-initiated superpixel segmentation algorithm based on color consistency is proposed. By evaluating the color consistency of the surrounding pixels and incorporating gradient sum information, the initial seeds are adaptively identified, thereby enhancing boundary adherence while reducing the number of superpixels in low-gradient regions. Quantitative evaluations on the BSDS500 and SBD datasets verifythe effectiveness and efficiency of the algorithm while also mitigating the trade-off between boundary adherence and regularity.

This study aims to explore the issue of product quality regulation on e-commerce platforms with the participation of social media users. By constructing an evolutionary game model, the interaction between social media users, merchants, and e-commerce platforms is examined. The results indicate that the behavior choices of merchants and platforms are driven by profit motives, while the speed of regulatory strategy evolution by social media users is positively correlated with merchants providing high-quality products and platforms adopting strict regulatory measures. This interaction accelerates the system's progression toward a more stable state, demonstrating that social media can effectively assist the regulatory functions of e-commerce platforms. The active participation of social media users, combined with strict regulatory measures from platforms, can create a positive feedback loop, guiding the e-commerce system toward a more rational and stable state. Social media oversight not only encourages merchants to offer high-quality products but also prompts platforms to adopt stricter regulatory measures, thereby enhancing the overall governance efficiency of e-commerce platforms.

The proactive safety of infrastructure construction personnel is achieved based on violation recognition model and real-time high-quality construction image data. Traditional inspection path planning algorithms have only considered the spatial attributes of inspection targets, neglecting the differences in risk attributes among various inspection targets. This paper presents a multi-objective inspection path planning model with differentiated risk coefficients. The optimization objective is to minimize the risk cost on construction sites. The minimum cost path planning issue is thus transformed into an optimal strategy problem under Markov decision process. A risk weight optimization function is designed to solve the optimal path strategy, and a DDQN algorithm based on a target weight optimization function(Weighted discount reward function DDQN,WDR-DDQN) is proposed. Compared to the A* path planning algorithm, the WDR-DDQN algorithm reduces the overall risk cost on construction sites by 5%-10%. In this study, the inspection strategy takes into account the spatial and risk attributes of the target. It is of great significance to enhance the proactive safety guarantee capability of infrastructure sites.

With the rapid development of information technology, it makes it possible to extract accurate and reliable textual information from specialized and complex case information, which plays an important auxiliary role in helping doctors and rehabilitators develop treatment plans. For this reason, the named entity recognition as a model for information extraction is proposed in this paper. Named Entity Recognition can automatically identify and classify key information in the text, assist doctors to quickly obtain information about the patient's medical history, treatment effects and other information, and formulate personalized rehabilitation plans. However, case data in specialized fields such as rehabilitation medicine are usually difficult to obtain, and the data quality is difficult to be guaranteed due to high data redundancy and little valid information. In this case, the performance of named entity recognition is greatly limited. For this reason, the study proposes a data enhancement strategy based on random masking and random exchange of entity text, which aims to optimize the ability of named entity recognition model to understand the context of data and identify relevant entities in the field of rehabilitation and healthcare, and improve the accuracy of named entity recognition. The experimental results demonstrate that the designed data enhancement method can improve the accuracy of entity recognition.

The mechanical ball milling method was used to treat the filter cake obtained from water-washed fly ash to evaluate the stabilization efficiency of heavy metals. The results show that under the conditions of 250 ℃, 50% water content in the filter cake, the addition of 10% SiO2, and milling for 6 h, the heavy metals met the requirements of the Pollution Control Standard for Domestic Waste Landfill(GB 16889-2024). When the water content in the filter cake was less than 50%, a higher water content resulted in better stabilization efficiency of heavy metals. After the milling, the reduced state of Cu decreased most significantly by 96.09%, while its oxidized state increased by 51.91%. The oxidized states of Zn, Cr, Cd and Pb decreased by 36.94%, 58.53%, 15% and 3.05%, respectively. Meanwhile, the residue states of these metals increased, which contributed to improving their stability and reducing the mobility.

The speciation distribution characteristics of ZnONPs in soil and its influencing factors are still unclear. In this study, we investigated the impact of ZnONPs size exposure concentration and soil physicochemical properties on the variation of Zn speciation in ZnONPs-contaminated soil. Compared to the blank soil, a significant increase in the proportion of exchangeable Zn was observed only in red soil(acidic) after the addition of ZnONPs. The application of ZnONPs significantly increased the proportion of carbonate-bound Zn in all tested soils, except for the lateritic soil. Over time, the exchangeable and carbonate-bound Zn in ZnONPs-treated soil gradually transformed into the Fe(Mn) oxide-bound forms. With increasing ZnONP mass ratio, the proportions of exchangeable Zn and Fe/Mn oxide-bound Zn increased, while the proportions of carbonate-bound Zn and organic matter-and sulfide-bound Zn showed no significant correlation with ZnONPs mass ratio. Moreover, larger-sized ZnONPs(90 nm) were more likely to transform into carbonate-bound and organic matter-and sulfide-bound forms in soil. These findings provide a theoretical basis for understanding the speciation transformation of ZnONPs in the environment and contribute to soil environmental risk assessment associated with ZnONP contamination.

Probiotics are a class of beneficial microbe that usually reside in the gut to perform a variety of advantageous functions. However, before probiotics from oral administration can successfully colonize the gut, they must overcome various challenges such as stomach acid, bile acid, digestive enzymes, and other adverse factors. Thus, there is an urgent need to develop safe and effective delivery systems to safeguard probiotics. Compared to traditional probiotic encapsulation strategies, single cell encapsulation is an effective method which could encapsulated single bacterial cell in one coated system. It could protect the probiotics from the harsh gastrointestinal environment and enhance their colonization. This review focuses on the latest research progress in delivery of single cell encapsulation system for oral delivery of probiotics, outlines the limitations of present microencapsulation techniques of probiotics, and highlights the potential advantages of single-cell encapsulation. Moreover, the characteristics and principles of different single cell encapsulation methods of probiotics were investigated. The mechanisms of single cell encapsulation to improve bioavailability and health benefits of single cell encapsulated probiotics were carefully described. Furthermore, the future challenges and prospects of single-cell encapsulation technology were discussed.

Nanostructured lipid carriers(NLC), a new generation of lipid-based delivery systems composed of a mixture of solid and liquid lipids as the core and stabilized by an emulsifier, have been successfully applied in various fields in recent years due to their high stability, high loading capacity, excellent biocompatibility, and controllable release of active substances. This paper first provides a brief overview of the classification of NLC and their preparation strategies, including organic solvent method, microchannel method, and high-energy emulsification method. Then characterization techniques such as dynamic light scattering(DLS), field-emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD), and differential scanning calorimetry(DSC) are introduced. Finally, the current applications of NLC in the fields of food, pharmacy, and cosmetics are summarized, offering technical references for their future development and application.