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Journal of Traffic and Transportation Engineering(English Edition) 2025年第01期 52-67页

作者： Xu Zhang Shunying ji Yang Feng Yongjun Li Chunfa Zhao School of Civil and Transportation Engineering Guangdong University of Technology State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong University State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of Technology

Railway ballast is easily contaminated by different fouling material and the fouled ballast always causes the deterioration of railway track. Many previous studies focused on the effect of a certain kind of fouling material on ballast performance, but few studies compared the influence of different fouling material. This paper presents a series of direct shear tests on the clean ballast and the fouled ballast mixed with coal fines or sand to understand the effects of different fouling material. A unified empirical model is proposed to well capture the shear stress-displacement responses of the clean and fouled *** equations are also obtained to characterize the variation of the nonlinear shear strength envelope of the fouled ballast with the fouling content. Based on these equations,a simple method is proposed to predict the shear strength of the fouled ballast using the shear test results of clean ballast. The measured results demonstrate significant differences between the effects of coal fines and sand on the shear behaviors of ballast, to which particular attention should be paid in order to take targeted maintenance measures for the fouled ballast. The mechanisms for the different effects of coal fines and sand are also analyzed to understand the roles that various fouling material plays in the fouled ballast.

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Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan Zhang Yi Yang Guangbin ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Response properties of geometries of coal penetrating fracture on seepage behavior

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International Journal of Mining Science and Technology 2025年第02期 191-211页

作者： Penghua Han Kai Wang jiewen Pang Xiaofeng ji Cun Zhang College of Engineering for Safety and Emergency Management Taiyuan University of Science and Technology School of Energy and Mining Engineering China University of Mining and Technology-Beijing Engineering Research Center of Green and Intelligent Mining for Thick Coal Seam Ministry of Education China University of Mining and Technology-Beijing

The fracture surfaces of coal-rock masses formed under mining-induced stress generally exhibit complex geometries, and the fracture geometry is one of the primary factors affecting the seepage characteristics of coal-rock penetrating fracture. This paper investigates the seepage characteristics of 5 groups of coal penetrating fracture(CPF) with different joint roughness coefficients(JRCs). Based on 3D morphology scanner tests and hydraulic coupling tests, a characterization method of effective geometric parameters in fracture surfaces under various confining pressures was improved, and a relationship between effective geometric parameters and the confining pressure is established. The results indicate that the nonlinear flow behavior in a CPF primarily includes three types: non-Newtonian fluid seepage under high confining pressure and low JRC, non-Darcy seepage under low confining pressure and high JRC, and the whole process of seepage characteristics between these two conditions. Among them, nonNewtonian fluid seepage is caused by significant fracture expansion, while non-Darcy seepage can be attributed to turbulence effects. During the seepage process, the geometric parameters with different JRC fracture samples all exhibit exponential changes with the increase of confining pressure. In addition,under high confining pressure, the effective contact ratio, effective fracture aperture, and void deviation ratio with high JRC fracture samples under high confining pressure increase by 93.5%, 67.4%, and 24.9%,respectively, compared with those of low JRC fracture samples. According to the variation of geometric parameters in a CPF with external stress, a seepage model considering geometric parameters in a CPF is proposed. By introducing the root mean square error(RMSE) and coefficient of determination(R2) to evaluate the error and goodness of fit between model curves and experimental data, it is found that the theoretical curves of model in this paper have the best matchi

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Speech at the Welcome Reception and 2025 Chinese New Year Celebration

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Beijing Review 2025年第6期68卷 I0006-I0008页

作者： Lin ji 不详

Your Excellency Chandrikapersad Santokhi,President of the Republic of Suriname,and the First Lady Mellisa Santokhi,Honorable Ministers and Members of Parliament,Distinguished Ambassadors and Representatives of International Organizations,Dear members of the Chinese community,Ladies and Gentlemen,Friends:Good evening!First of all,please allow me to extend a warm welcome to everyone attending this reception!My wife and I arrived in Suriname on November 3,2024,and were honored by the great importance attached by the Surinamese side.H.E.

关键词： everyone please attached

Ferulic acid alleviates long-term avermectin-induced damage to the spleen of carp and restores its inflammatory response and oxidative balance

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Journal of Environmental Sciences 2025年第5期151卷 616-626页

作者： Hanyu Wang Shenye Feng Enzhuang Pan Xiaomeng ji Mengyuan Zhou Shuai Zhang Baoshi Xu Huimiao Feng jilei Yin Zibo Dong jiangsu Key Laboratory of Marine Bioresources and Environment Co-Innovation Center of Jiangsu Marine Bio-industry TechnologyJiangsu Marine Pharmaceutical Resources Development Engineering Research CenterJiangsu Key Laboratory of Marine Pharmaceutical Compound ScreeningCollege of PharmacyJiangsu Ocean UniversityLianyungang 222005China Department of Traditional Chinese Medicine Jiangsu Union Technical Institute Lianyungang Branch institute of Traditional Chinese MedicineLianyungang 222006China

Extensive use of avermectin(AVM)in agriculture can seriously contaminate fish in *** acid(FA)is a strong antioxidant sourced from plants and is widely applied in food and medicine,but its protective function on the immunological damage caused by AVM is still *** this study,carp were chronically exposed to(1/1096 hr LC_(50))AVM for 30 day(s),with a dietary supplement of FA(400 mg/kg)to assess its effects on carp *** experimental groups(n=10)included:control,AVM-exposed(2.404μg/L),FA+AVM co-treated,and FA ***-term AVM exposure altered spleen tissue,reducing serum complement C3(p<0.01)and immunoglobulin M levels(p<0.001),and increasing proinflammatory tnf-α(p<0.001),il-6(p<0.001),il-1β(p<0.001),and inos mRNA levels,whilst down-regulating the anti-inflammatory tgf-β(p<0.05).Additionally,it disrupted the balance of oxidative stress indicators such asMDA(p<0.001),T-AOC,GSH,and CAT,leading to spleen tissue apoptosis(42.4%).However,the addition of FA reversed these conditions,elevated the anti-inflammatory factor,and improved spleen immune function following chronic exposure to AVMin ***,the ability to restore oxidative homeostasis in carp by adjusting the Nrf2/NQO-1 axis protected the health of spleen *** discovery also supports the development of fish feed for aquaculture.

关键词： Avermectin Ferulic acid Oxidative stress Inflammation response

Nitrogen addition promotes soil carbon accumulation globally

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Science China(Life Sciences) 2025年第1期68卷 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen jiangling Zhu Chengjun ji Biao Zhu lingli Liu jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan UniversityKunming 650500China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Soil is the largest carbon(C)reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N)deposition has been widely considered as a critical factor affecting soil organic carbon(SOC)storage,but its effect on SOC components with different stability remains ***,we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N *** analysis showed that N addition led to a significant increase in bulk SOC(6.7%),with greater increases in croplands(10.6%)and forests(6.0%)compared to grasslands(2.1%).Regarding SOC components,N addition promoted the accumulation of plant-derived C(9.7%–28.5%)over microbial-derived C(0.2%),as well as labile(5.7%)over recalcitrant components(–1.2%),resulting in a shift towards increased accumulation of plant-derived labile ***,N addition led to a greater increase in particulate organic C(11.9%)than mineral-associated organic C(3.6%),suggesting that N addition promotes C accumulation across all pools,with more increase in unstable than stable *** responses of SOC and its components were best predicted by the N addition rate and net primary ***,our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool,which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability

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极端条件下含能材料的模拟研究思考

高压物理学报 2025年第1期39卷 17-43页

作者：姬广富中国工程物理研究院流体物理研究所冲击波物理与爆轰物理全国重点实验室四川绵阳621999

含能材料在军事、民用和航天等领域具有广泛应用,极端条件下其物理化学性质会发生显著变化。通过模拟研究预测和优化含能材料性能具有重要意义,包括性能预测、优化设计、安全评估、成本效率控制等。为此,综述了极端条件下含能材料的研... 详细信息

含能材料在军事、民用和航天等领域具有广泛应用,极端条件下其物理化学性质会发生显著变化。通过模拟研究预测和优化含能材料性能具有重要意义,包括性能预测、优化设计、安全评估、成本效率控制等。为此,综述了极端条件下含能材料的研究背景、基本性质、模拟研究方法及进展、关键问题以及相关实验研究进展。其中,详细介绍了量子力学、分子动力学、蒙特卡罗和有限元等模拟方法及其研究进展,阐述了高压、高温、激光作用和界面效应等极端条件下模拟研究的关键问题,并列举了含能材料在撞击感度、化学释能规律、3D打印、绿色电合成、爆轰机理和超高含能材料合成等方面的实验研究进展。通过遴选代表性研究,展示了模拟研究在实际问题中的应用和解决方案。同时,介绍了一些最新研究成果,以反映该领域的最新进展和未来趋势。此外,详细讨论了跨学科研究的实现方式以及含能材料在极端条件下的安全性问题,包括可能的风险和预防措施。

关键词：含能材料极端条件模拟研究高压高温激光作用

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Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 224-231页

作者： WU Yuxuan XU Wenyuan YU Tianlai ji Yongcheng School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

关键词： polyurethane retarder setting time molecular dynamics diffusion coefficient

Carbon Dots-Modified Hollow Mesoporous Photonic Crystal Materials for Sensitivityand Selectivity-Enhanced Sensing of Chloroform Vapor

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Nano-Micro Letters 2025年第4期17卷 381-398页

作者： Junchen Liu ji Liu Zhipeng Li Liupeng Zhao Tianshuang Wang Xu Yan Fangmeng Liu Xiaomin Li Qin Li Peng Sun Geyu Lu Dongyuan Zhao State Laboratory On Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012People’s Republic of China Department of Chemistry and Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsState Key Laboratory of Molecular Engineering of PolymersCollaborative Innovation Center of Chemistry for Energy Materials(2011-iChEM)College of Chemistry and MaterialsFudan UniversityShanghaiPeople’s Republic of China School of Engineering and Built Environment Griffith UniversityNathanQLD 4111Australia

Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and ***,research on chloroform vapor sensing is still in its early stages,primarily due to the lack of specific recognition *** we report a mesoporous photonic crystal sensor incorporating carbon dots-based nanoreceptor(HMSS@CDs-PCs)for enhanced chloroform *** colloidal PC packed with hollow mesoporous silica spheres provides an interconnected ordered macro-meso-hierarchical porous structure,ideal for rapid gas sensing utilizing the photonic bandgap shift as the readout *** as-synthesized CDs with pyridinic-N-oxide functional groups adsorbed in the hollow mesoporous silica spheres are found to not only serve as the chloroform adsorption sites,but also a molecular glue that prevents crack formation in the colloidal *** sensitivity of HMSS@CDs-PCs sensor is 0.79 nm ppm^(-1)and an impressively low limit of detection is 3.22 ppm,which are the best reported values in fast-response chloroform vapor sensor without multi-signal *** positive response time is 7.5 s and the negative response time 9 ***,relatively stable sensing can be maintained within a relative humidity of 20%-85%RH and temperature of 25-55℃.This study demonstrates that HMSS@CDs-PCs sensors have practical application potential in indoor and outdoor chloroform vapor detection.

关键词： Carbon dots Photonic crystal sensors Sensitivity-enhanced sensing Selectivity-enhanced sensing Chloroform vapor sensing

基于改进瞪羚优化算法的UWSN三维定位算法

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控制与决策 2025年第1期40卷 80-86页

作者：付雷王骥广东海洋大学电子与信息工程学院广东湛江524088 广东省智慧海洋传感网及其装备工程技术研究中心广东湛江524088

为解决三维空间中的水下无线传感器网络(underwater wireless sensor networks, UWSN)传统DV-Hop算法定位误差大的问题,提出一种基于改进瞪羚优化算法(improved gazelle optimization algorithm, IGOA)的UWSN三维定位算法(IGOADV-Hop).首先,通过双通信半径修正节点跳数,对锚节点间的距离误差进行加权修正;然后,在瞪羚优化算法引入Logistic映射初始化种群,增加种群多样性;接着,在开发阶段引入位置更新动态权重系数,提升节点位置计算的全局寻优能力;最后,使用IGOA替代最小二乘法进行节点三维坐标计算,并在网络中加入移动节点和水下噪声构建动态UWSN.仿真实验结果表明,与传统DV-Hop算法和其他群智能优化算法相比,所提出算法定位精度更高.

关键词：水下无线传感器网络三维定位移动节点 DV-Hop算法瞪羚优化算法 Logistic映射动态权重系数

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