Table of Content

25 April 2025, Volume 53 Issue 4

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Architecture & Civil Engineering

Commercial Space Design Above Rail Transit Hub on Spatial Vitality

JIANG Tao, WANG Jing, WANG Yongdi

2025, 53(4):  1-12.  doi:10.12141/j.issn.1000-565X.240260

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Rail transit hubs naturally have advantages in terms of pedestrian flow. The development of multi-dimensional, mixed-use commercial spaces above these hubs has become a new construction model. The commercial spaces above rail transit hubs have become important places for passengers, commuters, and citizens to engage in consumption and social activities. The development of commercial spaces above most rail transit hubs is often large-scale, with complex spatial organization. This can lead to issues such as mismatched functional requirements, insufficient supply of service facilities, chaotic flow organization, low transfer efficiency, and poor spatial quality, resulting in insufficient guidance of pedestrian flow and low space utilization, which affects the vitality of commercial spaces and thus affects the healthy operation of commercial spaces. Therefore, this paper starts with the research on the vitality of commercial space above the rail transit hub. Firstly, it categorized the constituent elements of these commercial spaces, defining them in terms of functional organization, flow organization, and spatial construction across three dimensions. Then, two already constructed rail transit hub commercial spaces in China were selected for case study. Through field research and sample space screening, 15 indicators corresponding to the three dimensions were identified. The data analysis methods such as space syntax theory and SPSS correlation analysis were used to quantify the indicators. The study found that spatial vitality does not show a direct correlation with functional density, but it does exhibit a strong correlation with most flow organization indicators and all spatial construction indicators. The key factors influencing spatial vitality include functional density, spatial accessibility and visibility, entrances and exits, vertical transportation, and the location of resting areas. Finally, the specific operation of the design strategy was put forward in combination with the commercial space above the Chengdu station. The research content of this paper provides a design reference for the related design of the commercial space above the rail transit hub and offers new insights into related theoretical explorations.

Deflection Reliability Assessment Method of Long-Span Suspension Bridge Based on Random Field

CHENG Jin, SUN Kedi, YUAN Yi

2025, 53(4):  13-21.  doi:10.12141/j.issn.1000-565X.240076

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Long-span suspension bridges are costly to construct but play a crucial role in transportation networks due to their ability to handle high traffic volumes. As a control engineering project, the safety and reliability of long-span suspension bridges are primarily assessed using deterministic analysis methods, such as the finite element method, for calculation and analysis. However, in practical engineering, structural parameters exhibit uncertainty and simultaneously variability and correlation exist in spatial distribution. Hence, the influence of random field factors was incorporated. By adopting numerical analysis methods and integrating random field theory with reliability theory, a reliability assessment method for long-span suspension bridges based on random fields was proposed. This method primarily consists of three components: the use of the center-point method and correlation functions to handle random fields; the application of the finite element method for structural numerical analysis; and the use of the first-order second-moment method, specifically the design point method, to calculate structural reliability index. The specific implementation process of the method was introduced, and corresponding analysis programs were deve-loped. Several numerical examples were used to verify the accuracy and applicability of the method and the program. Finally, taking the three-tower four-span suspension bridge, the Wenzhou Oujiang North Bridge, as an engineering case, the reliability of its deflection under normal operating limit states was assessed considering the uncertainty of structural parameters as well as their spatial variability and correlation. The impact of random fields on the deflection reliability index of the Wenzhou Oujiang North Bridge was analyzed. Results indicate that the proposed method is suitable for the reliability assessment of long-span suspension bridges. When considering the random field, the deflection reliability index under the normal use limit state is found to be smaller compared to the calculation that ignores the random field. This indicates that neglecting the spatial variability and correlation of the structural parameters in a long-span suspension bridge leads to an overestimation of the deflection reliability under normal use limit state.

Stability Analysis of Cable-Supported Cylindrical Reticulated Shells Considering Initial Eccentricity of Members

JIANG Zhengrong, LIU Xiaoliang, SHI Kairong, SU Changwang, ZUO Zhiliang

2025, 53(4):  22-29.  doi:10.12141/j.issn.1000-565X.240092

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Currently, there is relatively limited research on the stability analysis of spatial structures considering the initial eccentricity of members. To reveal the influence laws of the initial eccentricity of members on the stability bearing capacity of cable-supported cylindrical reticulated shells, this paper proposed a simulation method of introducing the initial eccentricity of members by the end rigid rod and presented the ratio relationship of the elastic modulus between the rigid rod and the initial eccentric rod. Based on this, the random imperfection mode method was used to sequentially introduce the initial eccentricity of members into the perfect structure and the overall imperfect structure. An elasto-plastic process analysis was then conducted to examine the impact of the initial eccentricity of members and the simultaneous application of two types of imperfections on the nonlinear buckling behavior of cable-supported cylindrical reticulated shells. The results show that when the elastic modulus of the rigid rod is taken to be more than 100 times of that of the initial eccentric rod, the calculation results show minor differences. Therefore, the ratio of the elastic modulus between them is taken as 100. The coefficients of stability bearing capacity of cable-supported cylindrical reticulated shells are not remarkably reduced when introducing the initial eccentricity of members into the perfect structure (the maximum reduction is 8.27%), indicating that the structure is not very sensitive to the initial eccentricity of members, thus the adverse effects of the initial eccentricity of members can be ignored in engineering practice by balancing the calculation work. Compared with the perfect structure, the coefficients of stability bearing capacity of cable-supported cylindrical reticulated shells are significantly reduced by 27.64% when introducing the initial eccentricity of members into the overall imperfect structure. However, the reductions are slightly smaller than the sums of reductions when the two kinds of imperfections are introduced separately. The overall imperfection and the initial eccentricity of members introduced simultaneously have a certain extent coupling effect on the structural stabi-lity bearing capacity, and the effect of the former is more significant.

Structural Design and Deployment Analysis of a Novel Rib-Patterned Deployable Antenna Structure

DONG Yongcan, YUAN Xingfei, LI Shu, AKRAM Samy, DONG Shilin

2025, 53(4):  30-39.  doi:10.12141/j.issn.1000-565X.240270

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Inspired by the structural configurations of ribbed cable domes, this study introduced a novel rib-patterned deployable antenna structure, aiming to explore innovative design solutions for large-aperture antennas. Firstly, this paper designed a basic deployable module with a driving-locking joint. By sequentially assembling multiple such modules, an extendable arm was constructed, which serves as a radial support rib. Furthermore, multiple extendable arms were arranged in a circumferential array, with corresponding prestressed loop cables, resulting in the construction of a novel rib-ring deployable antenna structure. In its fully deployed state, this structure can be conceptualized as a cable-beam composite system. A simulation model of the structure was created using finite element analysis software, and modal analysis was conducted. Comparative results reveal that, relative to existing configurations, the proposed rib-ring deployable structure exhibits superior structural stiffness, indicating its potential for application in large-aperture antenna design. Building on these, the study investigated the application of the rib-patterned structure to large-aperture antennas, proposing a deployable antenna design with a diameter of 58.2 meters. To assess the feasibility of this design, a simulation model of the antenna was developed using multi-body dynamics simulation software Adams, and deployment motion simulations were performed both for the individual extendable arm and the overall structure. The results demonstrate that the designed structure can successfully deploy into position and achieve reliable locking, further verifying the feasibility and effectiveness of the proposed antenna design. The study indicates that the novel rib-ring deployable antenna structure combines the advantages of truss-type deployable structures, which offer high stiffness, and rib-type deployable structures, which provide a high deployment ratio. This research offers valuable insights for the structural selection of future large-aperture antennas.

Cost-Performance Analysis of Thin-Layer UHPC Encased I-Beam Shear Resistance

FAN Xueming, ZHOU Xiaopeng, YE Xiaohang, ZHAO Kun

2025, 53(4):  40-49.  doi:10.12141/j.issn.1000-565X.240332

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The steel structure has multiple advantages, including low carbon footprint, environmental friendliness, lightweight yet high strength, and excellent seismic performance. It has been widely used in high-rise buildings, large-span buildings and some civil buildings. However, its inherent problems such as buckling, corrosion and high cost hinder the further application of steel structures. The current anti-buckling and anti-corrosion measures for steel structures will greatly increase the cost of the structure and have a negative impact on the bearing capacity of the structure. Ultra-high performance concrete (UHPC) is a new type of fiber-reinforced cement-based composite material based on the maximum bulk density theory. It features high strength and excellent deformation capacity, along with outstanding durability properties, including superior resistance to water penetration, chloride ion infiltration, and freeze-thaw cycles. Nowadays, UHPC has been widely used in mechanical reinforcement and durability reinforcement of various structures. Recent research work shows that the combination of steel structure and UHPC can effectively realize the complementary advantages of the two. While giving full play to the excellent characteristics of light weight and high strength of steel structure, it greatly reduces the harm of fatigue, corrosion and instability to steel structure. This study focused on a newly developed thin-layer UHPC encased I-beam, which has been widely applied in practice. A sample database was established through finite element simulation analysis using Abaqus. At the same time, the comprehensive evaluation index of shear performance and shear cost performance of composite beams was proposed based on the radar chart method. The response surface-Monte Carlo method was employed to analyze the influence of four different response surfaces on the web size parameters of the composite beam. The analysis results show that there is a significant positive correlation between the shear performance of the composite beam and its cost performance. Moreover, as the thickness of the I-beam web increases, both shear performance and cost-effectiveness initially rise and then decline, reaching a peak at a specific thickness. This study provides valuable engineering insights for optimizing the design of I-beam encased UHPC composite beams.

Modified Calculation of Axial Compressive Bearing Capacity of Ultra-High-Strength Concrete Precast Column Considering Constraint Effect of Stirrup

WANG Suguo, QIU Wei, CHEANG I, FAN Binghui

2025, 53(4):  50-60.  doi:10.12141/j.issn.1000-565X.240310

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To study the effect of stirrup confinement on the axial compressive bearing capacity of ultra-high-strength concrete (UHSC) precast columns, this paper first conducted an axial compression contrast experiment between full-size UHSC column and ordinary column, and investigated the difference of crack development, failure pattern and ultimate bearing capacity of these two type columns. Based on the experimental results, further finite element analysis was conducted to simulate 36 full-scale UHSC columns. The study focused on analyzing the effects of stirrup configuration, stirrup spacing, and stirrup diameter on the axial compressive performance of UHSC columns. Combining the experimental findings and parametric analysis results, a modified calculation formula for the axial compressive bearing capacity of UHSC columns considering stirrup confinement was proposed. The proposed formula was then compared with the calculation formula in the current Code for Design of Concrete Structures. The results show that: the ultimate bearing capacity of equal-strength designed UHSC column is higher than that of ordinary concrete column, but it is more brittle than ordinary concrete, especially when reaching the ultimate bearing capacity; the confinement effect of stirrups on the core concrete enhances the axial compressive bearing capacity of UHSC columns. Changes in stirrup configuration, stirrup spacing, and stirrup diameter have a significant impact on the ultimate bearing capacity and peak compressive strain of UHSC columns; the proposed axial compressive bearing capacity correction formula for UHSC columns incorporates the differences between UHSC columns and ordinary concrete columns, considering the confinement effect of stirrups on the core concrete. Compared to the calculation formula provided in the code, which does not account for stirrup confinement and is primarily applicable to ordinary concrete columns, this formula better utilizes the material’s potential while ensuring safety margins. It can serve as a useful reference for practical engineering design.

Mechanical Engineering

Study on Heat Transfer Characteristics of Aluminum Plates with Different Surface Micro-Functional Structures

LI Yong, WANG Huipan, HE Jiabin, JIANG Kejun, CHEN Xinyu

2025, 53(4):  61-71.  doi:10.12141/j.issn.1000-565X.240208

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The development needs of miniaturization, lightness and low cost of electronic products have posed significant challenges to the design and manufacture of heat dissipation modules. In order to solve the heat dissipation pro-blem of thin high-performance routers and small electronic devices, 6 kinds of aluminum plate radiators with surface micro-functional structures were designed on the basis of smooth aluminum plate radiators. According to the newly designed aluminum plate radiators, an experimental test platform was built. Under the conditions of natural convection and micro-convection, the heat dissipation performance of the 6 new aluminum plate radiators was compared with that of the smooth aluminum plate radiators. The results show that under the condition of natural convection, when the heat source power is 3.0~6.0 W, the heat dissipation performance of the square pin-fin aluminum plate is the best. Compared with the smooth surface aluminum plate, the average Nusselt number is increased by about 18%, the product of heat transfer coefficient and heat transfer area is increased by about 17%, and the heat source temperature is reduced by about 2.0 K. Compared with smooth surface aluminum plate, the average Nusselt number of round pin-fin aluminum plate increases by 7%, the product of heat transfer coefficient and heat transfer area increases by about 5%, and the heat source decreases by about 1.3 K. After surface treatment, the sandblasted square pin-fin aluminum plate can reduce the heat source temperature by 2.0~3.9 K, and the nano-carbon square pin-fin aluminum plate can reduce the heat source temperature by 5.3~8.6 K. The sandblasted round pin-fin aluminum plate can reduce the heat source temperature by 1.9~2.5 K, and the nano-carbon round pin-fin aluminum plate can reduce the heat source temperature by 4.9~7.7 K. Under the micro-convection condition of wind speed of 2 m/s, the round pin-fin aluminum plate has the best heat dissipation performance. Compared with the smooth surface aluminum plate, the average Nusselt number is increased by about 8%, the temperature of the heat source is reduced by 3.6 K at 6 W, and the thermal resistance is reduced by 18%. Compared with the smooth surface aluminum plate, the average Nusselt number of the square pin-fin aluminum plate is increased by about 6%, the temperature of the heat source can be reduced by 2.4 K at 6 W, and the thermal resistance is reduced by 11%. The higher the heat source power, the better the heat dissipation performance of the aluminum plate with surface micro-functional structure compared with the smooth surface aluminum plate.

Wear Evaluation and Residual Life Prediction Method for Rail Grinding Wheels

HE Zhe, ZHANG Yuying, LIU Shangkun, GAO Chunlei

2025, 53(4):  72-80.  doi:10.12141/j.issn.1000-565X.240173

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Rail grinding is a technology that removes the top fatigue layer of rails by applying high speed rotating grinding wheels. When the grinding wheels become abrasion, it typically leads to a decrease in material removal efficiency and an increase in grinding zone temperature. To prevent these issues from negatively affecting grinding operations, timely replacement of worn-out grinding wheels is necessary. This paper proposed a neural network-based method for predicting the wear level and residual life of rail grinding wheels, enabling the optimal timing for wheel replacement. The principle of this method is as follows: the axial acceleration signal of the motor spindle connected to the grinding wheel was collected, and based on this signal, characteristic parameters that describe the wear level of the grinding wheel were extracted. These characteristic parameters were then transformed using the Z-score method, which removes the dimensionality of the parameters and improves their comparability. After that, the XGBoost algorithm was employed to filter the most relevant features that are strongly correlated with the wheel’s service life. A fusion strategy integrating wear time and wheel wear volume was adopted as the criterion for assessing the wear and service life. Constructing a neural network model that mapped the filtered feature parameters to both the wear volume and the grinding wheel thickness. The experimental data along with the grinding wheels abrasion was obtained by using the experimental device. The data was divided into mutually independent training and validation sets, which were used to train and validate the constructed neural network, respectively. The results show that the method achieves comparable accuracy in both the training and validation sets. In the validation set, the accuracy for determining the wear level of the grinding wheel is 87.9%, with misclassified samples mainly concentrated in the transition zone of wear progression. The prediction accuracy for the grinding wheel life is -5.3%. Additionally, the method demonstrates a certain level of generalizability across different grinding process parameters.

Optimized Design of Foamed Asphalt Spraying Device Considering Viscosity Change and State Change

CHENG Haiying, LI Nanxi, MA Dengcheng, WU Wenxia

2025, 53(4):  81-89.  doi:10.12141/j.issn.1000-565X.240300

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As the key equipment of asphalt pavement regeneration construction, the cold recycling machine can realize cold in-place recycling and improve the construction efficiency. The cold recycling machine faces the issue of asphalt accumulating easily at the nozzle when spraying foamed asphalt, as well as uneven flow rates across the nozzles. To solve the above problems, it is necessary to increase the pressure of foamed asphalt nozzle to reduce asphalt accumulation and balance the flow of each nozzle. This article first started from the essence of asphalt foa-ming behavior, and based on the multiphase flow mixing theory, considered the viscoelasticity of asphalt and phase changes of water during the asphalt foaming process. The viscosity-temperature characteristic function of asphalt and the phase change function of water were introduced into the calculation model to modify the fluid volume (VOF) model and establish a control model for asphalt foaming behavior. Next, numerical simulations were conducted and the results were compared with experimental data. It was found that the errors of the asphalt foaming behavior control model in terms of nozzle pressure and flow rate were 9.2% and 7.7%. Based on the aforementioned asphalt foa-ming behavior model, a numerical simulation model for the foamed asphalt spraying device was then constructed, simulating the foamed asphalt spraying process according to the designed experimental scheme. Based on the simulation results, a Kriging surrogate model was constructed on the Isight platform, and a multi-objective optimization model was established with the goal of improving outlet pressure and reducing the mass flow rate difference of each nozzle. The multi-objective optimization model was solved by the NSGA-Ⅱ algorithm. Finally, a Pareto solution set was obtained and analyzed. The results show that when the asphalt pipe diameter is 0.74a, the foaming water pipe diameter is 0.58b, the foamed asphalt nozzle diameter is 0.6c, and the number of foamed asphalt nozzles is d, the performance of the foamed asphalt spraying device is optimal. By considering the characteristics of asphalt foaming behavior, the performance of the foamed asphalt spraying device is enhanced by adjusting the nozzle pressure and balancing the flow rates across the nozzles.

Optimal Selection of UAV Launch Parameters Based on SSA-BP Neural Network

JIA Huayu, ZHENG Huilong, ZHOU Hong, ZHANG Qian

2025, 53(4):  90-101.  doi:10.12141/j.issn.1000-565X.230781

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Rocket assisted zero length launch is an important form of UAV launch. The selection of launch parameters such as launch angle, booster angle, and booster thrust directly affects the success or failure of UAV launch mission. In the design phase of unmanned aerial vehicle rocket assisted zero length launch, key parameters such as launch angle, booster angle, and booster thrust are selected based on engineering experience. However, this approach faces several challenges, including long iteration cycles for optimal parameter selection, poor design interactivity, and the potential risk of causing instability in the UAV’s flight posture. This study focused on a specific UAV and conducts dynamic and kinematic modeling of its launch phase, constructing a six-degree-of-freedom nonlinear model. A UAV launch trajectory parameterization simulation software was developed using QT/C++ software, and the software’s effectiveness was verified through comparison with real UAV launch test data. At the same time, in order to solve the problem of autonomous optimization of launch parameters, sparrow search algorithm (SSA), particle swarm optimization algorithm (PSO), and genetic algorithm (GA) optimization modules were introduced based on the backpropagation neural network (BP neural network) parameter prediction model. A UAV launch parameter optimization method based on SSA optimized BP neural network was proposed to eliminate the overfitting and local optimal effects of BP neural network in the parameter prediction process. The absolute error (MAE), average percentage error (MAPE), and root mean square error (RMSE) of the parameter prediction results were calculated to comprehensively evaluate the superiority of SSA-BP in predicting launch parameters, and the rationality of the launch parameter selection was verified through launch trajectory verification. The results indicate that the SSA-BP model has the highest prediction accuracy and robustness for launch parameters, and can provide a design basis for the autonomous selection of launch parameters in the engineering design stage of unmanned aerial vehicle launch subsystems.

Design and Disturbance Suppression of a Permanent Magnet Flexible Spherical Wrist Driven by Rotating Magnetic Coaxial Effect

ZHANG Yongshun, LIU Zhijun, LIU Zhenhu, WANG Li

2025, 53(4):  102-112.  doi:10.12141/j.issn.1000-565X.240377

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Current permanent magnet spherical joints commonly face issues such as complex electromagnetic drive structures, difficulties in coupled magnetic field modeling, magnetic moment singularities, and insufficient resistance to external disturbances. To solve the problems, this study developed a permanent magnet flexible direct-drive spherical joint with an embedded fully suspended permanent magnet rotor as the core based on the rotational fixed-axis effect, where the rotor axis of the permanent magnet always tends to align with the axis of rotation of the magnetic field. The new stator consists of a three-axis orthogonal nested combination of two sets of saddle coils and one set of Helmholtz coils. To solve the redundancy issue of magnetic moment control variables, a three-phase current formula was used to superimpose the spatial universal rotating magnetic field with the yaw and pitch angles as independent control variables. This enables the decoupling of the yaw and pitch magnetic moments of the permanent magnet rotor in the rotating magnetic field, as well as the realization of the universal spherical joint’s two-degree-of-freedom motion (yaw and pitch) under the guidance of the rotating magnetic field’s axis. Furthermore, the system stability was proved using the Lyapunov function, and a non-singular fast terminal sliding mode control method optimized by a fuzzy algorithm was applied to suppress chatter and reduce trajectory errors at the output end. The theoretical simulation results verified the effectiveness of the controller. Compared with sliding mode control method without fuzzy algorithm optimization,when external disturbance is applied, the sliding mode controller with fuzzy algorithm optimization can effectively suppress chattering, improve tracing speed, reduce output trajectory errors. Simulations and experiments show that the spherical joint has a simple electromagnetic structure, along with convenient analytical modeling of the magnetic field. The input current variables correspond one-to-one with the output magnetic moment variables. The system exhibits good anti-interference capability and effective chatter suppression, achieving fast tracking of the desired trajectory for the spherical joint. The dynamic tracking performance is excellent, and the system demonstrates improved adaptability in complex environments.

Food Science & Technology

Effect of Laccase Synergy with Ferulic Acid on the Rheological Properties of Wheat Dough and the Quality of Bread

LI Bing, HE Min, HE Ni, PAN Zhiqin, ZHANG Xia, CHEN Xinran, LI Junyi, LI Lin

2025, 53(4):  113-124.  doi:10.12141/j.issn.1000-565X.240221

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China is a large wheat-growing country, but the quality of domestic wheat flour can not fully meet the production demands of high-quality bread products. At present, research on the effects of laccase (LAC) and ferulic acid (FA) on wheat bread quality mainly focuses on their individual effects on bread baking performance, while the combined addition of LAC and FA on wheat bread baking performance remains unclear. Therefore, this study utilized various instruments, including a texture analyzer, rheometer, low-field nuclear magnetic resonance analyzer, scanning electron microscope, and gas-phase ion mobility spectrometry-flavor analysis coupled instrument, to investigate the effects of LAC and FA on the rheological properties, moisture migration characteristics, and microstructure of wheat dough.The results show that compared to the control and FA groups, the doughs in the LAC and LAC+FA groups exhibit lower weakening, with increased maximum stretching resistance and reduced extensibility, leading to dough hardening. Additionally, results from low-field nuclear magnetic resonance analysis showed that both individual and combined additions of LAC and FA could convert the immobile water from the T_21b state to the T_21a state. This indicates that LAC and FA, whether added alone or in combination, reduce the freedom of water, leading to a tighter binding of water with dough components, thus influencing moisture migration in the dough. Scanning electron microscopy (SEM) results of the dough show that the complex addition of LAC and FA results in a more complete and homogeneous gluten network. In terms of bread quality, both the LAC group and the LAC+FA group reduce the hardness of the bread crumb, with minimal impact on the composition and content of volatile compounds. Therefore, the addition of LAC and its combination with FA positively contribute to improving dough strength and bread quality.

Effects of Borneol Essential Oil Separation Components onthe Motility and Biofilm Formation of Escherichia coli

FAN Penghui, CHEN Guanghao, LIU Zirui, CAI Xinyu, WAN Yuanyuan, SU Jianyu

2025, 53(4):  125-134.  doi:10.12141/j.issn.1000-565X.240156

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To investigate the effects of different components of borneol essential oil, separated by molecular distillation, on the motility and biofilm formation of Escherichia coli, the study was conducted as follows: First, gas chromatography-mass spectrometry (GC-MS) was employed to analyze the volatile components of the crude borneol essential oil, its light fraction, and its heavy fraction. Next, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the three components against E. coli ATCC 25922 were determined using the double dilution method and plate coating method, respectively. Finally, the impact of these three components on the swimming and swarming motility, as well as biofilm formation of E. coli ATCC 25922, was studied using motility assays and crystal violet staining. The results show that the crude borneol essential oil, light fraction, and heavy fraction contain 27, 24, and 19 volatile components, respectively. The highest relative content of volatile components is D-borneol (19.93%) in the crude oil, eucalyptol (19.36%) in the light fraction, and D-borneol (28.92%) in the heavy fraction. The MIC and MBC of the crude oil, light fraction, and heavy fraction against E. coli are 6.25 μL/mL, and all three components are able to delay bacterial growth at sub-inhibitory concentrations. At 1/2 MIC and 1/4 MIC, all three borneol essential oil components reduce the swimming and swarming motility of E. coli and inhibited biofilm formation. The heavy fraction of borneol essential oil exhibits superior inhibition of E. coli motility and biofilm formation compared to the crude oil and light fraction. These findings indicate that molecular distillation can enrich the antibacterial active components in borneol essential oil, effectively enhancing its added value and demonstrating broad application prospects.

Triple ERA Rapid Detection Method for Pathogens in Refrigerated Meat Products

YANG Yange, WU Zhanwen, LIU Tong, WANG Shuai, WEI Ying, ZHAO Jiansong, LI Hongna, LI Tao, ZHANG Feng

2025, 53(4):  135-146.  doi:10.12141/j.issn.1000-565X.240169

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Meat products, being rich in nutrients, often provide an ideal environment for microbial growth.Even under low temperature storage, most microorganisms remain active and retain partial virulence. Therefore, screening for pathogenic bacteria in meat products is crucial. This study developed a triple-fluorescence ERA (enzyme-mediated recombinase polymerase amplification) rapid detection method based on enzyme recombinase amplification (ERA) technology. Performance analyses were conducted on the method’s specificity, sensitivity, and detection limits. Additionally, the applicability of the method was validated using commercially available refrigerated meats and compared to the industry standard SN/T 1870—2016 real-time fluorescent polymerase chain reaction (PCR) method. The results show that a triple-fluorescent ERA rapid detection method was successfully constructed for three key pathogens: Staphylococcus aureus, Salmonella and Listeria monocytogenes. After optimization, the method could simultaneously detect the three pathogens within 12 min from a single reaction. The minimum detection limit is 10^-3 ng/μL. In artificially contaminated samples, after 6 hours of pre-enrichment, the method can simultaneously detect contamination levels of 1 CFU/mL for all three pathogens. The sampling results of commercially available refrigerated meat show that the detection rates for Staphylococcus aureus, Salmonella, and Listeria monocytogenes were 19.35%, 12.90%, and 6.45%, respectively, which align with the detection results of the industry standard SN/T 1870―2016. These fully demonstrate the accuracy and applicability of the method. This study not only helps reduce the risk of disease caused by foodborne pathogens but also provides solid technical support for future rapid detection of foodborne pathogens.