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Experimental investigation on enhanced damage to fuel tanks by reactive projectiles impact

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Defence Technology（防务技术） 2021年第2期17卷 599-608页

作者： Hai-fu Wang jian-wen xie Chao Ge Huan-guo Guo Yuan-feng Zheng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Enhanced damage to the full-filled fuel tank,impacted by the cold pressed and sintered PTFE/Al/W reactive material projectile(RMP)with a density of 7.8 g/cm3,is investigated experimentally and *** fuel tank is a rectangular structure,welded by six pieces of 2024 aluminum plate with a thickness of 6 mm,and filled with RP-3 aviation *** results show that the kerosene is ignited by the RMP impact at a velocity above 1062 m/s,and a novel interior ignition phenomenon which is closely related to the rupture effect of the fuel tank is ***,the traditional steel projectile with the same mass and dimension requires a velocity up to 1649 m/s to ignite the *** on the experimental results,the radial pressure field is considered to be the main reason for the shear failure of *** mechanism considerations,the chemical energy released by the RMP enhances the hydrodynamic ram(HRAM)effect and provides additional ignition sources inside the fuel tank,thereby enhancing both rupture and ignition ***,to further understand the enhanced ignition effect of RMP,the reactive debris temperature inside the kerosene is analyzed *** initiated reactive debris with high temperature provides effective interior ignition sources to ignite the kerosene,resulting in the enhanced ignition of the kerosene.

关键词： Reactive material projectile Fuel tank Enhanced damage effect Enhanced ignition mechanism Impact behavior

From earthquake resistance structure to earthquake resilience city–urban seismic resilience assessment

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 1-13页

作者： xie Lili Zhao Yonggang wen Weiping Zhai Changhai Key lab of Structures Dynamic Behaviour and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China Institute of Engineering Mechanics China Earthquake AdministrationHarbin 150080China

Earthquakes pose significant perils to the built environment in urban *** avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient *** to the intricacy of the concept of urban seismic resilience(USR),its assessment is a large-scale system engineering *** assessment of USR should be based on the notion of urban seismic capacity(USC)assessment,which includes casualties,economic loss,and recovery time as *** loss is also included in the assessment of USR in addition to these *** assessment indicator system comprising five dimensions(building and lifeline infrastructure,environment,society,economy,and institution)and 20 indicators has been devised to quantify *** analytical hierarchy process(AHP)is utilized to compute the weights of the criteria,dimensions,and indicators in the urban seismic resilience assessment(USRA)indicator *** the necessary data for a city are obtainable,the seismic resilience of that city can be assessed using this *** illustrate the proposed methodology,a moderate-sized city in China was selected as a case *** assessment results indicate a high level of USR,suggesting that the city possesses strong capabilities to withstand and recover from potential future earthquakes.

关键词： urban seismic capacity urban seismic resilience assessment analytic hierarchy process functionality loss

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin WANG Qijiao XIAO Huahua CHEN Xiaoxiao xie Fan ZENG wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace UniversityShenyang 110136China State Key Laboratory of Fire Science University of science and Technology of ChinaHefei 230027China AVIC Shenyang Aircraft Design and Research Institute Shenyang 110035China

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature(T=300-400 K),initial pressure(P=0.1-0.3 MPa),turbulence intensity(u'=1.0-2.7 m/s),oxygen volumetric percentage(φ(O_(2))=15%-21%)and carbon dioxide volumetric percentage(φ(CO_(2))=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale(D6-D8)disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： geometry characteristics large-scale wrinkling wavelet decomposition network topology fan-stirred turbulent combustor

High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

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Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai Yi Li Yabo xie Qiancheng Chen Xin Zhang jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 136-143页

作者： Di-Chao Chen xie Liu Changqing Xu Da-jian Wu Ying Cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal UniversityNanjing 210023China Key Laboratory of Modern Acoustics School of PhysicsNanjing UniversityNanjing 210093China

Vortex transmutation utilizes a periodic system,which not only enables the alteration of the topological charge(TC)of unstable input vortices but also facilitates their transformation into stable *** approach is crucial for investigating the characteristics of vortices in various wave ***,we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES).The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete *** results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures,enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Chattering-Free Fault-Tolerant Cluster Control and Fault Direction Identification for HIL UAV Swarm With Pre-Specified Performance

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 183-197页

作者： Pei-Ming Liu Xiang-Gui Guo jian-Liang Wang Daniel Coutinho Lihua xie the Beijing Engineering Research Center of Industrial Spectrum Imaging School of Automation and Electrical Engineering University of Science and Technology Beijing the Shunde Graduate School of University of Science and Technology Beijing IEEE Autonomous Intelligent Systems Department Hangzhou Innovation Institute of Beihang University the Department of Automation and Systems Universidade Federal de Santa Catarina the School of Electrical and Electronic Engineering Nanyang Technological University

In this paper, the problem of pre-specified performance fault-tolerant cluster consensus control and fault direction identification is solved for the human-in-the-loop(HIL) swarm unmanned aerial vehicles(UAVs) in the presence of possible nonidentical and unknown direction faults(NUDFs) in the yaw *** control strategy begins with the design of a pre-specified performance event-triggered observer for each individual *** observers estimate the outputs of the human controlled UAVs, and simultaneously achieve the distributed design of actual control signals as well as cluster consensus of the observer *** is worth mentioning that these observers require neither the high-order derivatives of the human controlled UAVs' output nor a priori knowledge of the initial conditions. The fault-tolerant controller realizes the pre-specified performance output regulation through error transformation and the Nussbaum function. It should be pointed out that there are no chattering caused by the jump of the Nussbaum function when a reverse fault occurs. In addition, to provide a basis for further solving the problem of physical malfunctions, a fault direction identification algorithm is proposed to accurately identify whether a reverse fault has occurred. Simulation results verify the effectiveness of the proposed control and fault direction identification strategies when the reverse faults occur.

关键词： Chattering-free cluster consensus fault direction identification human-in-the-loop (HIL) nonidentical and unknown direction faults (NUDFs) pre-specified performance swarm unmanned aerial vehicles (UAVs)

Structural engineering of high-entropy alloys for advanced electrocatalytic reactions

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Tungsten 2025年第1期7卷 1-31页

作者： Qiao xie Ying-Jie Yu Hai-Jun Zhang Ya-Ping Deng wen Lei The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Department of Chemical Engineering Waterloo Institute for Sustainable Energy Waterloo Institute for Nanotechnology University of Waterloo

High-entropy alloys(HEAs) have emerged as promising candidates to replace traditional precious metal catalysts,owing to their unique chemical and physical *** review commences by revisiting the fundamental concepts of HEAs,including their synthesis methods and structural control strategies in *** underscores the critical role of meticulously manipulating both macroscopic and microscopic structures of the HEAs to optimize their catalytic performance.A deep understanding of the structure-activity relationship in HEAs across various configurations is pivotal in developing more effective *** review methodically encapsulates the research progress of structural control strategies for HEAs in achieving efficient energy conversion,with the aim of gaining a better understanding of the relationship between structure and *** review concludes by summarizing the current achievements and challenges,and suggestions for potential future directions of HEAs in the fields of energy conversion and environmental purification.

关键词： Electrocatalytic Energy conversion High-entropy alloys Structural modulation

Isolation and bioactivity evaluation of flavonoids and their derivatives from Miliusa balancae

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Isolation and bioactivity evaluation of flavonoids and their...

Potential preservative mechanisms of cardiac rehabilitation pathways on endothelial function in coronary heart disease

中国化学会第十届全国天然有机化学学术会议

作者： wen-Hui Pan Yi-Fu Guan Xun Song Dong-Ying Wang wen-jian xie Hong-Jie Zhang School of Chinese Medicine Hong Kong Baptist University

In our previous research,bioassay-directed fractionation of Miliusa sinensis Finet and Gagnep.(Annonaceae)led to the isolation of potential anticancer lead *** a continuous study,we found that ***,the plant in the same genus,showed anticancer *** discover its active compounds,the plant materials of *** were recollected and extracted with *** of the dichloromethane extract led to

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来源： cnki会议评论

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Science China(Life Sciences) 2025年第1期68卷 158-175页

作者： wen-Tao Sun jian-Yong Du Jia Wang Yi-Long Wang Er-Dan Dong Research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital(Qingdao Municipal Hospital)Schoolof Health and Life SciencesUniversityof Health and Rehabilitation SciencesQingdao 266071China Department of Cardiology and Instituteof Vascular Medicine Peking University Third HospitalTheInstituteofCardiovascular SciencesPeking UniversityState Key Laboratoryof Vascular Homeostasisand RemodelingPeking UniversityBeijing 100191China

Cardiac rehabilitation,a comprehensive exercise-based lifestyle and medical management,is effective in decreasing morbidity and improving life quality in patients with coronary heart *** function,an irreplaceable indicator in coronary heart disease progression,is measured by various methods in traditional cardiac rehabilitation pathways,including medicinal treatment,aerobic training,and smoking ***,studies on the effect of some emerging cardiac rehabilitation programs on endothelial function are *** article briefly reviewed the endothelium-beneficial effects of different cardiac rehabilitation pathways,including exercise training,lifestyle modification and psychological intervention in patients with coronary heart disease,and related experimental models,and summarized both uncovered and potential cellular and molecular mechanisms of the beneficial roles of various cardiac rehabilitation pathways on endothelial *** exercise training and some lifestyle interventions,the enhanced bioavailability of nitric oxide,increased circulating endothelial progenitor cells(EPCs),and decreased oxidative stress are major contributors to preventing endothelial dysfunction in coronary heart ***,the preservation of endothelial-dependent hyperpolarizing factors and inflammatory suppression play *** the one hand,to develop more endothelium-protective rehabilitation methods in coronary heart disease,adequately designed and sized randomized multicenter clinical trials should be advanced using standardized cardiac rehabilitation programs and existing assessment *** the other hand,additional studies using suitable experimental models are warranted to elucidate the relationship between some new interventions and endothelial protection in both macro-and microvasculature.

关键词： cardiac rehabilitation coronary heart disease endothelial function