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Acta Mechanica Sinica 2013年第1期29卷 110-122页

作者： Hai-Long Chen feng-nian jin Hua-Lin Fan PLA University of Science and Technology Key Laboratory of Bridge-structure Engineering Chongqing Jiaotong University Laboratory of Structural Analysis for Defense Engineering and Equipment College of Mechanics and Materials Hohai University Key Laboratory of Road & Bridge and Underground Engineering of Gansu Province Lanzhou Jiaotong University

Due to the wide applications of arches in underground protective structures, dynamic analysis of circular arches including soil-structure interactions is important. In this paper, an exact solution of the forced vibration of circular arches subjected to subsurface denotation forces is obtained. The dynamic soil-structure interaction is considered with the introduction of an interfacial damping between the structure element and the surrounding soil into the equa- tion of motion. By neglecting the influences of shear, rotary inertia and tangential forces and assuming the arch incompressible, the equations of motion of the buried arches were set up. Analytical solutions of the dynamic responses of the protective arches were deduced by means of modal super- position. Arches with different opening angles, acoustic impedances and rise-span ratios were analyzed to discuss their influences on an arch. The theoretical analysis suggests blast loads for elastic designs and predicts the potential failure modes for buried protective arches.

关键词： Underground protective arches - Dynamic soilstructure interaction Dynamic responses Analytical solution

Crushing behaviors of buckling-induced metallic meta-lattice structures

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Defence Technology（防务技术） 2022年第8期18卷 1301-1310页

作者： Jian-hua Dong Yong-jun Wang feng-nian jin Hua-lin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China Department of Civil Engineering Nanyang Institute of TechnologyNanyang473004China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

Thin-walled lattice materials can be applied as energy absorbers in protective structures of civil defense. In this paper, quasi-static in-plane crushing tests were carried out to investigate the crushing behavior and energy absorption of buckling induced meta-lattice structures (BIMSs) with different central angles made of plastic iron material DT3 and formed by wire cutting technique. Three crushing patterns were revealed and analyzed. The test results clearly show that the initial peak force (IPF), the crushing force efficiency (CFE), the specific energy absorption (SEA) and the mean crushing force (MCF) can be substantially improved by introducing buckling pattern into the straight-walled lattice structure. The MCF of the BIMS was consistently predicted based on the simplified super folding element (SSFE) and the flattening element.

关键词： Buckling induced meta-lattice structure (BIMS) Crushing force efficiency

Vibration attenuation of meta-mortar with spring-mass resonators

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Defence Technology（防务技术） 2023年第2期20卷 11-23页

作者： San-feng Liu Hai-long Chen Yang Liu Hu-guang He Xi-yue An feng-nian jin Hua-lin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing210016China

Metamaterial based on local resonance has excellent vibration attenuation ability in low *** this research,an attempt was performed to make meta-mortar with spring-mass resonators to attenuate vibration and shock ***-spring-mass resonators and dual-spring-mass resonators were designed and made using lead or aluminum blocks and SWPB springs encased by PMMA(polymethyl methacrylate)or aluminum *** resonators were placed into mortar blocks to make metamortar *** attenuation effect was investigated by sweeping vibration with frequency from 50 Hz to 2000 *** these meta-mortar blocks exhibit excellent vibration attenuation ability in the designed band *** dual-spring-mass resonators,meta-mortar blocks have two distinct vibration attenuation bands.

关键词： Meta-mortar Vibration attenuation Spring-mass resonators

Polyurea coating for foamed concrete panel:An efficient way to resist explosion

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Defence Technology（防务技术） 2020年第1期16卷 136-149页

作者： Yi-shun Chen Bo Wang Bei Zhang Qing Zheng Jian-nan Zhou feng-nian jin Hua-lin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

Autoclaved aerated concrete(AAC) panels have ultra-light weight,excellent thermal insulation and energy absorption,so it is an ideal building material for protective *** improve the blast resistance of the AAC panels,three schemes are applied to strengthen the AAC panels through spraying 4 mm thick polyurea coating from top,bottom and *** three-point bending tests,the polyurea-coated AAC panels have much higher ultimate loads than the un-coated panels,but slightly lower than those strengthened by the carbon fiber reinforced plastics(CEFRPs).Close-in explosion experiments reveal the dynamic strengthening effect of the polyurea *** scaled distances of the strengthened AAC panels are acquired,which are valuable for the engineering application of the AAC panels in the extreme loading *** coatings efficiently enhance the blast resistance of the bottom and double-sided polyurea-coated AAC *** is interesting that the polyurea-coated AAC panels have much more excellent blast resistance than the CFRP reinforced AAC panels,although the latter have better static mechanical properties.

关键词： Autoclaved aerated concrete Polyurea Explosion Failure

Blast responses of polyurea retrofitted utility tunnel reinforced with basalt fibre reinforced polymer bars

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Defence Technology（防务技术） 2022年第5期18卷 755-771页

作者： Jian-nan Zhou Xiao-shuo Chen Yin-zhi Zhou Wen-ye Wang Peng Wang Xin-li Kong Ying Xu Han-sheng Geng feng-nian jin State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China

Polyurea coating and carbon fibre reinforced polymer reinforcing techniques were applied to retrofit a severely damaged urban utility tunnel(UUT).The blast responses of the retrofitted UUT were investigated through in-filed explosion experimental tests,and the displacements,strains,accelerations,and damage were *** retrofitted UUT exhibited comparable or even better blast resistance than the intact *** the polyurea coating was flexible,it exhibited excellent performance in improving the blast resistance of the damaged *** the UUT reinforced with basalt fibre reinforce polymer(BFRP)bars has smaller damage compared with the UUT reinforced with steel bars,its retrofitting is simple,and the cost is *** roof was simplified as an elastically simple support one-way *** beam theory was adopted to analyse the dynamic responses of UUT roof considering the interaction between soil and structure,which agree well with the experiments in the first three cases.

关键词： Urban utility tunnel Retrofitting Polyurea CFRP Explosion

Blast resistance evaluation of urban utility tunnel reinforced with BFRP bars

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Defence Technology（防务技术） 2021年第2期17卷 512-530页

作者： Qiang Zhou Hu-guang He San-feng Liu Xiao-shuo Chen Ze-xun Tang Yang Liu Zhen-yu Qiu Sen-sen Li He Wang Yin-zhi Zhou Jian-nan Zhou Hua-lin Fan feng-nian jin State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing210016China

To improve corrosion-resistance of shallow-buried concrete urban utility tunnels(UUTs),basalt fiber reinforced polymer(BFRP)bars are applied to reinforce *** the UUT must have excellent survival capability under accidental explosions,a shallow-buried BFRP bars reinforced UUT(BBRU)was designed and *** blast experiments were carried out on this *** responses,damage evolutions and failure styles of the BBRU under repetitive explosions were *** tunnel roof is the most vulnerable component and longitudinal cracks develop along the *** the scaled distance is larger than 1.10 m/kg1/3,no cracks are observed in the *** the BBRU is severely damaged,there are five cracks forming and developing along the *** roof is simplified as a clamped-supported one-way slab,proved by the observation that the maximum strain of the transverse bar is much larger than that of the longitudinal *** responses of the roof slab are predicted by dynamic Euler beam theory,which can consistently predict the roof displacement under large-scaleddistance *** with the UUT reinforced with steel bars,the BBRU has advantages in blast resistance with smaller deflections and more evenly-distributed cracks when the scaled distance is smaller than 1.260 m/kg1/3 and the steel bars enter plastic *** elastic defamation of the BFRP bars endows the UUT more excellent blast resistance under small-scaled-distance explosions.

关键词： Utility tunnel BFRP bars Explosion Dynamic response Crack Dynamic theory

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中国牡蛎蚧属一新种记述(半翅目:盾蚧科)

Entomotaxonomia 2006年第4期28卷 265-267页

作者：冯纪年袁水霞章伟年植保资源与病虫害防治教育部重点实验室西北农林科技大学植保学院陕西杨凌712100 中国科学院上海生命科学院植物生理生态研究所昆虫博物馆上海200032

记述中国牡蛎蚧属1新种——浙江牡蛎蚧Lepidosapheszhejiangensis,***.。模式标本存于中国科学院上海生命科学院植物生理生态研究所昆虫博物馆。

关键词：半翅目盾蚧科牡蛎蚧属新种中国

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo jin Cong-feng Qiao Yue-Liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

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Neural Regeneration Research 2025年第8期20卷 2199-2217页

作者： Zi Ye Runqing Liu Hangxing Wang Aizhen Zuo Cen jin Nan Wang Huiqi Sun Luqian feng Hua Yang The Clinical Medical College Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Infectious Diseases Department of Internal MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina School of Medical Imaging Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Gastroenterology First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion *** studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion ***,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional *** this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and *** therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box *** review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins *** review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk *** Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug ***,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

关键词： apoptosis autophagy blood-brain barrier dietary supplements drug hormones inflammation neuroprotection oxidative stress prognosis pyroptosis reperfusion injury risk factors RNA therapeutics

Enhanced solid-electrolyte interface efficiency for practically viable hydrogen-air fuel cell systems

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Journal of Energy Chemistry 2025年第1期100卷 356-368页

作者： Venkitesan Sakthivel Dong jin Yoo Graduate School Department of Energy Storage/Conversion Engineering (BK21 FOUR) Hydrogen and Fuel Cell Research Center Jeonbuk National University Jeonju Department of Life Science Jeonbuk National University

Proton exchange membrane fuel cells （PEMFCs） provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall ***,sulfonated poly（1,4-phenylene ether-ether sulfone）(SPEES),an aromatic hydrocarbon polymer,has garnered considerable attention as an alternative to Nafion ***,the long-term durability and stability of SPEES present a significant *** this context,we introduce a potential solution in the form of an additive,specifically a core–shell-based amine-functionalized iron titanate （A–Fe2TiO5）,which holds promise for improving the lifetime,proton conductivity,and power density of SPEES in *** modified SPEES/A–Fe2TiO5composite membranes exhibited notable characteristics,including high water uptake,enhanced thermomechanical stability,and oxidative ***,the SPEES membrane loaded with 1.2 wt%of A–Fe2TiO5demonstrates a maximum proton conductivity of 155 mS cm-1,a twofold increase compared to the SPEES membrane,at 80°C under 100%relative humidity （RH）.Furthermore,the 1.2 wt%of A–Fe2TiO5/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm-2and a current density of 1148 mA cm-2at 60°C under 100%RH,with an opencircuit voltage decay of 0.05 m V/h during 103 h of continuous *** study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEMFC applications.

关键词： Acid-base Hybrid membrane Proton conductivity Polymer electrolyte fuel cell Single-cell performance