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Defence Technology（防务技术） 2023年第3期21卷 184-195页

作者： Chao Ge Die Hu Jin wang Qingbo Yu Haifu Wang Yuanfeng Zheng School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China

To investigate the thermal response and initiation behavior of ternary fluoropolymer-matrix PTFE/Al/W reactive materials,a research combining shock loading tests and trans-scale modelling is conducted.On the basis of a good agreement of the numerically simulated and tested shock wave propagation,the significant impact of component ratios and particle sizes on the evolution of mesoscopic temperature,hot-spots and initiation is well characterized and analyzed.Results demonstrate that as the content of W increases,the range of mesoscopic high-temperature area increases and tends to distribute more uniform,while material with smaller W particles causes more intense particle deformation and larger temperature rise.The time to reach the critical temperature shows positive correlation to the content of W,while the critical temperature of hot-spots shows negative correlation to the particle size of W.For PTFE/Al/W of high density,with the increase of W particle size,the reaction rate decrease,however the time to reach the peak reaction rate shortens.

关键词： deformation shock loading

Reactive jet density distribution effect on its penetration behavior

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Defence Technology（防务技术） 2023年第6期24卷 190-202页

作者： Huan-guo Guo Cheng-hai Su Yi-qiang Cai Suo He Qing-bo Yu Haifu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

In this paper,the penetration mechanism of reactive jet with non-uniform density distribution is studied.The simulations show that the density deficit occurs in the whole reactive jet,and the density increases from the jet tip to tail.The density of jet tip is approximately 1.5 g/cm3,which is lower than that of the reactive liner materials.The X-ray experiments show similar results with the simulations.The density decreasing effect of jet tip has a significant influence on the penetration behavior when the reactive jet impacts steel plate.According to the simulation results,this paper assumes that the density gradient in the jet section has linear distribution.Then,the deflagration pressure generated by each jet element at the bottom of crater is introduced into the Bernoulli equation.Based on the virtual origin model and Szendrei-Held equation,the analytical models for penetration depth and radial cratering of reactive jet with the density reduction are obtained.Moreover,to further prove the validity of analytical models,the penetration experiments of the reactive liner shaped charge against steel plate under different standoffs are carried out.There is a convergence between the analytical crater profiles and experimental results when reactive jets penetrate steel plates under different standoffs,especially at standoff of 1.5 and 2.0charge diameters.

关键词： Shaped charge Reactive jet Density distribution Jet penetration Virtual origin

Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability

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Defence Technology（防务技术） 2024年第2期32卷 242-253页

作者： Tao Sun Haifu Wang Shipeng wang Chao Ge Die Hu Pengwan Chen Yuanfeng Zheng Beijing Institute of Technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China Xi'an Institute of Electromechanical Information Technology Xi'an710065China

Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used.Three types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and tested.The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over time.Moreover,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact.From simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy cluster.The unique formation structure determines the damage modes of the aluminum plate and the steel plate.Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content.With increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration.However,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

关键词： Reactive materials Al-PTFE composites Reactive liner X-ray Penetration

Enhanced structural damage behavior of liquid-filled tank by reactive material projectile impact

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Defence Technology（防务技术） 2024年第1期31卷 211-229页

作者： Jianwen Xie Yuanfeng Zheng Zhenyang Liu Chengzhe Liu Aoxin Liu Pengwan Chen Haifu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was studied in detail.PTFE/Al/W RMPs with steel-like and aluminum-like densities were prepared by a pressing/sintering process.The projectiles impacted a liquid-filled steel tank with front aluminum panel at approximately 1250 m/s.The corresponding cavity evolution characteristics and HRAM pressure were recorded by high-speed camera and pressure acquisition system,and further compared to those of steel and aluminum projectiles.Significantly different from the conical cavity formed by the inert metal projectile,the cavity formed by the RMP appeared as an ellipsoid with a conical front.The RMPs were demonstrated to enhance the radial growth velocity of cavity,the global HRAM pressure amplitude and the front panel damage,indicating the enhanced HRAM and structural damage behavior.Furthermore,combining the impact-induced fragmentation and deflagration characteristics,the cavity evolution of RMPs under the combined effect of kinetic energy impact and chemical energy release was analyzed.The mechanism of enhanced HRAM pressure induced by the RMPs was further revealed based on the theoretical model of the initial impact wave and the impulse analysis.Finally,the linear correlation between the deformation-thickness ratio and the non-dimensional impulse for the front panel was obtained and analyzed.It was determined that the enhanced near-field impulse induced by the RMPs was the dominant reason for the enhanced structural damage behavior.

关键词： Reactive material projectile Hydrodynamic ram Enhanced structural damage Liquid-filled tank Impact

An improved quaternion Gauss–Newton algorithm for attitude determination using magnetometer and accelerometer

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Chinese Journal of Aeronautics 2014年第4期27卷 986-993页

作者： Liu Fei Li Jie wang haifu Liu Chang School of Mechatronical Engineering Beijing Institute of Technology

For the vector attitude determination, the traditional optimal algorithms which are based on quaternion estimator（QUEST） measurement noise model are complicated for just two observations. In our application, the magnetometer and accelerometer are not two comparable kinds of sensors and both are not small field-of-view sensors as well. So in this paper a new unit measurement model is derived. According to the Wahba problem, the optimal weights for each measurement are obtained by the error variance researches. Then an improved quaternion Gauss–Newton method is presented and adopted to acquire attitude. Eventually, simulation results and experimental validation employed to test the proposed method demonstrate the usefulness of the improved algorithm.

关键词： Accelerometer Attitude determination Gauss-Newton algorithm Magnetometer Measurements

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活性毁伤材料及其应用技术研究进展

中国科学:技术科学 2023年第9期53卷 1434-1448页

作者：王海福向镜安北京理工大学爆炸科学与技术国家重点实验室北京100081

活性毁伤体制弹药战斗部技术,是武器毁伤领域近二十年发展起来的颠覆性前沿技术方向,为大幅度提升弹药战斗部威力开辟了新途径,成为支撑和引领高效毁伤技术发展的关键核心技术.本文首先从现役弹药战斗部威力形成方式着手,分析大幅提升... 详细信息

活性毁伤体制弹药战斗部技术,是武器毁伤领域近二十年发展起来的颠覆性前沿技术方向,为大幅度提升弹药战斗部威力开辟了新途径,成为支撑和引领高效毁伤技术发展的关键核心技术.本文首先从现役弹药战斗部威力形成方式着手,分析大幅提升威力面临的技术瓶颈,阐述活性毁伤体制弹药战斗部技术特点及优势.在此基础上,重点阐述活性毁伤材料技术、终点效应表征技术和武器化应用技术三方面研究进展.在活性毁伤材料技术方面,重点阐述材料体系、制备方法及力热化耦合响应等研究进展.在终点效应表征技术方面,重点阐述动能侵彻效应、化学能释放效应、结构毁伤增强效应、引燃和引爆增强效应等研究进展.在武器化应用技术方面,重点阐述活性毁伤材料在杀爆类、聚能类和侵彻类等弹药战斗部上应用研究进展,并讨论发展方向.

关键词：毁伤技术与弹药工程活性毁伤增强战斗部活性毁伤材料撞击引发含能材料

沪科版高中化学教科书实验探究特色解读及建议

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化学教学 2024年第5期 22-26页

作者：王海富经志俊南京市教育科学研究所江苏南京210002 南京市第九中学江苏南京210018 江苏省泗阳中学江苏泗阳223700

基于“强化实验探究,落实课程标准要求”“引领实验创新,提升实验育人价值”的视角,解读“新仪器改进实验装置;新视角优化探究效果;绿色化聚焦环境保护;数字化凸显现代技术;重对比加强证据推理;重开放关注方案设计”等沪科版高中化学教... 详细信息

基于“强化实验探究,落实课程标准要求”“引领实验创新,提升实验育人价值”的视角,解读“新仪器改进实验装置;新视角优化探究效果;绿色化聚焦环境保护;数字化凸显现代技术;重对比加强证据推理;重开放关注方案设计”等沪科版高中化学教科书实验探究的特色。并提出“梳理探究主题,理解实验探究意义”“聚焦学习主题,适度整合探究实验”“基于课标要求,规划学生必做实验”“结合实验条件,合理采用创新素材”等实施建议。

关键词：实验探究实验创新沪科版高中化学教科书实验教学建议

毛竹和日本柳杉幼苗对土壤氧化亚氮排放的影响及微生物机制

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Journal of Plant Ecology 2022年第2期15卷 277-285页

作者： haifu Fang Yu Gao Qiang Zhang Lili Ma Baihui wang Nasir Shad Wenping Deng Xiaojun Liu Yuanqiu Liu Ling Zhang Jiangxi Key Laboratory of Silviculture College of ForestryJiangxi Agricultural UniversityNanchang 330045China

毛竹(Phyllostachys edulis)向日本柳杉(Cryptomeria japonica)林的扩张现象越发普遍,其扩张对大气重要温室气体氧化亚氮(N_(2)O)排放的影响也引起了更多的关注,而其微生物机制尚不明确。本研究通过添加微生物抑制剂链霉素和扑海因分别... 详细信息

毛竹(Phyllostachys edulis)向日本柳杉(Cryptomeria japonica)林的扩张现象越发普遍,其扩张对大气重要温室气体氧化亚氮(N_(2)O)排放的影响也引起了更多的关注,而其微生物机制尚不明确。本研究通过添加微生物抑制剂链霉素和扑海因分别抑制细菌和真菌活性,连续观测土壤N_(2)O排放速率以及相关土壤养分和植物生物量。研究结果表明:(i)毛竹土壤N_(2)O的排放速率显著高于日本柳杉;与对照相比,细菌抑制剂、真菌抑制剂及其交互作用均对N_(2)O排放速率具有显著抑制效应,但三者之间无显著差异;(ii)毛竹生物量显著高于日本柳杉;(iii)日本柳杉土壤有机质、全氮和铵态氮显著高于毛竹土壤,日本柳杉土壤pH和全磷显著低于毛竹土壤。真菌抑制剂降低了土壤有机质含量,细菌抑制剂降低了土壤硝态氮含量。真菌抑制剂与物种在影响土壤pH、全磷和铵态氮方面具有显著交互作用。细菌抑制剂与物种在影响土壤全氮方面有显著交互作用。综上所述,毛竹和日本柳杉在生长过程中土壤N_(2)O排放速率不同,毛竹幼苗土壤N_(2)O排放及生物量均高于日本柳杉。细菌抑制剂和真菌抑制剂对N_(2)O的排放速率均具有一定抑制作用。因而,在全球气候变化背景下,应进一步深入了解森林生态系统物种组成和变化对N_(2)O排放的影响,以有效评估毛竹扩张等导致的生物多样性变化对全球N_(2)O排放的贡献。

关键词：微生物抑制剂毛竹扩张日本柳杉氧化亚氮排放

Effect of Microstructure of Composite Powders on Microstructure and Properties of Microwave Sintered Alumina Matrix Ceramics

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Journal of Materials Science & Technology 2013年第5期29卷 429-433页

作者： Hanmin Bian Yong Yang You wang Wei Tian haifu Jiang Zhijuan Hu Weimin Yu Department of Materials Science Harbin Institute of Technology Tianjin Cement Industry Design & Research Institute Co. Ltd. School of Materials Science and Engineering Hebei University of Technology China Gas Turbine Establishment National Defense Science and Technology Key Lab for Reliability and Environment Engineering Technology Beijing Institute of Spacecraft Environment Engineering

Two kinds of different structured alumina-titania composite powders were used to prepare alumina matrix ceramics by microwave sintering. One was powder mixture of alumina and titania at a micron-submicron level, in which fused-and-crushed alumina particles （micrometers） was clad with submicron-sized titania. The other was powder mixture of alumina and titania at nanometer-nanometer level, in which nano-sized alumina and nano-sized titania particles were homogeneously mixed by ball-milling and spray dried to prepare spherical alumina-titania composite powders. The effect of the microstructure of composite powders on microstructure and properties of microwave sintered alumina matrix ceramics were investigated. Nano-sized composite （NC） powder showed enhanced sintering behavior compared with micro-sized composite （MC） powders. The as- prepared NC ceramic had much denser, finer and more homogenous microstructure than MC ceramic. The mechanical properties of NC ceramic were significantly higher than that of MC ceramic, e.g. the flexural strength, Vickers hardness and fracture toughness of NC ceramic were 85.3%, 130.3% and 25.7% higher than that of MC ceramic, respectively. The improved mechanical properties of NC ceramic compared with that of MC ceramic were attributed to the enhanced densification and the finer and more homogeneous microstructure through the use of the nanostructured composite powders.

关键词： Al2O3 Composites Microwave processing Mechanical properties

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境外铁路车站到发线有效长度研究

铁道工程学报 2021年第4期38卷 1-6页

作者：孙海富王海忠刘家良中国铁路设计集团有限公司天津300308

研究目的:境外铁路车站到发线有效长的规定与中国有所不同,安全防护距离的含义也有所区别。在开展境外铁路设计时,没有统一的设计标准。本文对国内外铁路车站到发线有效长度进行分析,基于欧洲列控系统,提出境外铁路车站到发线有效长度... 详细信息

研究目的:境外铁路车站到发线有效长的规定与中国有所不同,安全防护距离的含义也有所区别。在开展境外铁路设计时,没有统一的设计标准。本文对国内外铁路车站到发线有效长度进行分析,基于欧洲列控系统,提出境外铁路车站到发线有效长度的设计方案,对境外铁路设计具有较强的借鉴意义和指导作用。研究结论:(1)铁路车站到发线有效长度主要包括站台(列车)长度、安全防护距离、警冲标至绝缘节的距离等;(2)安全防护距离包括车载定位误差、BTM天线至车头距离、缓解速度对应的紧急制动距离;(3)对于ETCS-1级列控系统,16辆、8辆编组动车组贯通式车站到发线有效长度分别为630 m、380 m,尽头式车站分别为565 m、335 m;对于ETCS-2级列控系统,16辆、8辆编组动车组贯通式车站到发线有效长度分别为580 m、330 m,尽头式车站分别为545 m、305 m;(4)当条件受限时,可以采取适当缩小安全防护距离或者采取上下行非对称停车等措施缩短车站到发线有效长度。

关键词：境外铁路车站到发线有效长度研究