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Analytical study on the dynamic displacement response of a curved track subjected to moving loads

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 867-879页

作者： ke-fei LI Wei-ning liu Valeri MARKINE zhi-wei HAN School of Civil Engineering Beijing Jiaotong University Beijing MTR Construction Administration Corporation Railway Engineering Group Faculty of Civil Engineering and Geosciences Delft University of Technology

A closed-form out-of-plane dynamic displacement response of a curved track subjected to moving loads was *** track structure was modeled as a planar curved Timoshenko beam periodically supported by the double-layer spring-damping *** general dynamic displacement response induced by the moving loads along the curve on the elastic semi-infinite space was firstly obtained in the frequency domain,according to the Duhamel integral and the dynamic reciprocity *** the case of the periodic curved track structure subjected to moving loads,the dynamic displacement equation was simplified into a form of summation within the basic track cell instead of the *** transfer function for the curved track was expressed in the form of a transfer *** and series moving loads were involved in the calculation *** the verification of the analytical model,the mid-span vertical deflection of a simply support curved beam subjected to moving load was recalculated and compared with the same case in the *** research results indicate that:under the same moving loads,the displacement response of the curved track decreases slightly with the increasing track radius,and the displacement response of the curved track with the radius greater than or equal to 600 m is almost equivalent to the displacement response of the straight track;the frequency spectrum of the curved track is more abundant than that of the straight track,which may result in more wheel-rail resonance and rail corrugation in the curved lines.

关键词： Curved track Moving loads Dynamic displacement Analytical solution Transfer function

Qualitative Description of Swashing Motion States on Mild Beach Slope

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China Ocean Engineering 2019年第4期33卷 412-423页

作者： YIN Jing ZOU zhi-li FANG ke-zhao liu Yan-li State key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China key Laboratory of Sea-Area Management Technology National Marine Environmental Monitoring Center Dalian 116024 China

The swashing motion on mild beach slope is dominated by the motion of low frequency waves (LFWs). Companying such a motion, there are two types of swashing motion states, occurrence or no occurrence of LFW’s collision. The present study distinguishes the two states qualitatively by relating it to the number of generated LFWs for the case of two incident wave groups. A simplified swashing index is established theoretically for this purpose. A series of related experiments were performed to observe the generated out-going LFWs on different mild slope from 1:20 to 1:160 and to determine the critical value of the swashing index. Numerical simulations based on higher order Boussinesq equations are also performed to help the recognition of the LFWs generated in the experiment.

关键词： swashing surf beat braking wave low frequency wave wave groups

基于功能化COFs材料的样品前处理技术在新兴污染物中的研究进展

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分析测试学报 2025年第1期44卷 12-24页

作者：潘自宇刘智敏许志刚昆明理工大学理学院云南昆明650500

新兴污染物因具有环境持久性、生物累积性、生物毒性以及在环境中痕量存在等特点而备受全球众多国家关注。因此,对环境、食品以及生物样品中的新兴污染物进行高灵敏检测至关重要。传统样品前处理技术存在耗时长、吸附剂用量大,以及对不... 详细信息

新兴污染物因具有环境持久性、生物累积性、生物毒性以及在环境中痕量存在等特点而备受全球众多国家关注。因此,对环境、食品以及生物样品中的新兴污染物进行高灵敏检测至关重要。传统样品前处理技术存在耗时长、吸附剂用量大,以及对不稳定污染物的分析准确性差等缺点,因此,亟需开发设计具有高选择性、高传质效率的新型材料作为前处理技术的吸附剂,以实现新兴污染物的高选择、高灵敏检测。共价有机骨架材料(COFs),特别是功能化的COFs材料,因具有比表面积大、结构可设计、稳定且构筑基元丰富等诸多优点而被广泛用于新兴污染物的富集。该文主要综述了近年来功能化COFs材料的合成策略及其作为样品前处理吸附剂在环境、食品和生物样品中新兴污染物中的分析应用,并对该类材料的未来发展趋势进行了展望。

关键词：新兴污染物功能化COFs材料样品前处理技术

表面印迹微球在水相介质样品前处理中的应用研究进展

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分析测试学报 2025年第1期44卷 61-72页

作者：王思涛刘智敏许志刚昆明理工大学理学院云南昆明650500

氢键通常是分子印迹聚合物识别模板分子的主要机制,由于水分子等诸多影响因素带来的干扰,有效识别水环境中的分析物一直是分子印迹技术面临的一大挑战。表面印迹微球具有比表面积大和易于修饰等特性,能够被灵活运用以满足各种水相样品... 详细信息

氢键通常是分子印迹聚合物识别模板分子的主要机制,由于水分子等诸多影响因素带来的干扰,有效识别水环境中的分析物一直是分子印迹技术面临的一大挑战。表面印迹微球具有比表面积大和易于修饰等特性,能够被灵活运用以满足各种水相样品前处理的需求,是克服水相识别困难的有效方法之一。该文综述了近年来水相识别表面印迹微球的各种制备策略及其代表性应用,包括不同基底、亲水性识别、非氢键的协同识别和基于特殊组件的表面印迹微球;从作用力和识别机制层面讨论了在水相介质中识别分子时的干扰因素及其调控策略,并进一步介绍了表面印迹微球在水相样品前处理中的应用;最后探讨了表面印迹微球在水相样品前处理领域面临的挑战及未来研究趋势。

关键词：表面印迹微球水相识别样品前处理制备策略

Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin Dai Xuefeng liu Xin Ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

Inhibiting ceramide synthase 5 expression in microglia decreases neuroinflammation after spinal cord injury

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Neural Regeneration Research 2025年第10期20卷 2955-2968页

作者： Wei Zhang Yubao Lu Ruoqi Shen Yingjie Wu Chenrui liu Xingxing Fang Liangming Zhang Bin liu Limin Rong Department of Spine Surgery The Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina National Medical Products Administration(NMPA)key Laboratory for Quality Research and Evaluation of Cell Products GuangzhouGuangdong ProvinceChina Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery GuangzhouGuangdong ProvinceChina Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery GuangzhouGuangdong ProvinceChina

Microglia,the resident monocyte of the central nervous system,play a crucial role in the response to spinal cord ***,the precise mechanism remains *** investigate the molecular mechanisms by which microglia regulate the neuroinflammatory response to spinal cord injury,we performed single-cell RNA sequencing dataset analysis,focusing on changes in microglial *** found that the MG1 subpopulation emerged in the acute/subacute phase of spinal cord injury and expressed genes related to cell pyroptosis,sphingomyelin metabolism,and neuroinflammation at high ***,we established a mouse model of contusive injury and performed intrathecal injection of siRNA and molecular inhibitors to validate the role of ceramide synthase 5 in the neuroinflammatory responses and pyroptosis after spinal cord ***,we established a PC12-BV2 cell co-culture system and found that ceramide synthase 5 and pyroptosis-associated proteins were highly expressed to induce the apoptosis of neuron *** ceramide synthase 5 expression in a mouse model of spinal cord injury effectively reduced ***,ceramide synthase 5-induced pyroptosis was dependent on activation of the NLRP3 signaling *** ceramide synthase 5 expression in microglia in vivo reduced neuronal apoptosis and promoted recovery of neurological ***2g7 formed a“bridge”between sphingolipid metabolism and ceramide synthase 5-mediated cell death by inhibiting the NLRP3 signaling ***,these findings suggest that inhibiting ceramide synthase 5 expression in microglia after spinal cord injury effectively suppressed microglial pyroptosis mediated by NLRP3,thereby exerting neuroprotective effects.

关键词： ceramide synthase 5 gasdermin D microglia neuroinflammation NLRP3 nuclear factor kappa B Pla2g7 pyroptosis sphingomyelin metabolism spinal cord injury

地震致伤残住院儿童少年创伤后应激障碍随访研究

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中华流行病学杂志 2009年第10期30卷 1092-1093页

作者：李西荣郭兰婷刘可智辛博黄明金李元媛梁雪梅李园孙锦华四川大学华西医院心理卫生中心成都610041 四川大学华西医院小儿外科成都610041

创伤后应激障碍（PTSD）指个体经历强烈精神创伤后出现的精神障碍，主要表现为反复闯入意识、梦境的创伤体验、高度惊觉状态、与社会隔离和回避行为以及注意力不集中、创伤性事件回忆困难等。患者社会功能受损，有的终身丧失工作和生活... 详细信息

创伤后应激障碍（PTSD）指个体经历强烈精神创伤后出现的精神障碍，主要表现为反复闯入意识、梦境的创伤体验、高度惊觉状态、与社会隔离和回避行为以及注意力不集中、创伤性事件回忆困难等。患者社会功能受损，有的终身丧失工作和生活能力。本研究以从地震灾区因伤残转运到医院住院治疗的儿童少年患者这一特殊群体为对象，探讨PTSD检出率、症状特征及其影响因素。

关键词：鱼震创伤后应激障碍随访研究儿童少年

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： zhi Li Yang Wei Kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （<0.7 V） and excellent cyclic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2998-3012页

作者： Yuan Zhao Yidan Zhang Xin liu Jian Zhang Ya Gao Shuyue Li Cui Chang Xiang liu Guofeng Yang Department of Geriatrics Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Neurosurgery The Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina

Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease *** proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of *** this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s *** a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western *** results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease ***,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control ***,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated *** together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced n

关键词： biomarker diagnosis exosomes N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein