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High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model

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Defence Technology（防务技术） 2024年第2期32卷 553-571页

作者： xu Li Yan Liu Junbo Yan Zhenqing Shi Hongfu Wang yingliang xu Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China China Research and Development Academy of Machinery Equipment Beijing100089China

The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 *** study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic *** the hypersonic penetration test,eight ogive-nose AerMet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/*** erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered *** examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration ***,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation ***,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present *** upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or *** to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit.

关键词： High-speed penetration Concrete target Erosion Projectile nose evolution model

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Experimental and numerical analyses of the effect of fibre content on the close-in blast performance of a UHPFRC beam

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Defence Technology（防务技术） 2024年第1期31卷 242-261页

作者： Junbo Yan Qiyue Zhang Yan Liu yingliang xu Zhenqing Shi Fan Bai Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Limited research has been conducted on the influences of fiber content on close-in blasting characteristics for ultrahigh-performance fiber-reinforced concrete(UHPFRC)*** paper aims to address this knowledge gap through experimental and mesoscale numerical *** were conducted on ten UHPFRC beams built with varying steel fiber volumetric fractions subjected to close-in explosive ***,this study considered other parameters,such as the longitudinal reinforcement type and *** the case of UHPFRC beams featuring normal-strength longitudinal reinforcement of diametersΦ12,Φ16,andΦ20,a reduction in maximum displacement by magnitudes of19.6%,19.5%,and 17.4%was observed,respectively,as the volumetric fractions of fiber increased from1.0%to 2.5%.In addition,increasing the longitudinal reinforcement ratio and using high-strength steel longitudinal reinforcement both significantly reduced the deformation characteristics and increase the blasting resistances of UHPFRC ***,the effects on the local crushing and spalling damage were not significant.A mesoscale finite element model,which considers the impacts of fiber parameters on UHPFRC beam behaviors,was also established and well correlated with the test ***,parametric analyses were further conducted to examine the impacts of the steel fiber content and length and the hybrid effects of various types of microfibers and steel fibers on the blasting performance of UHPFRC beams.

关键词： Blast performance Close-in blast Fiber content Mesoscale approach UHPFRC beams

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Research on the quasi-isentropic driving model of aluminized explosives in the detonation wave propagation direction

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Defence Technology（防务技术） 2024年第2期32卷 596-618页

作者： Hongfu Wang Yan Liu Fan Bai Chao He yingliang xu Qiang Zhou Chuan Xiao Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Research and Development Academy of Machinery Equipment Beijing100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Taking CL-20(Hexanitrohexaazaisowurtzitane)-based aluminized explosives with high gurney energy as the research object, this research experimentally investigates the work capability of different aluminized explosive formulations when driving metal flyer plates in the denotation wave propagation *** research results showed that the formulations with 43 μm aluminum(Al) powder particles(The particle sizes of Al powder were in the range of 2~43 μm) exhibited the optimal performance in driving flyer plates along the denotation wave propagation direction. Compared to the formulations with Al powder 13 μm, the formulations with Al powder 2 μm delivered better performance in accelerating metal flyer plates in the early stage, which, however, turned to be poor in the later stage. The CL-20-based explosives containing 25% Al far under-performed those containing 15% Al. Based on the proposed quasi-isentropic hypothesis, relevant isentropy theories, and the functional relationship between detonation parameters and entropy as well as Al reaction degree, the characteristic lines of aluminized explosives in accelerating flyer plates were theoretically studied, a quasi-isentropic theoretical model for the aluminized explosive driving the flyer plate was built and the calculation methods for the variations of flyer plate velocity, Al reaction degree, and detonation product parameters with time and axial positions were developed. The theoretical model built is verified by the experimental results of the CL-20-based aluminized explosive driving flyer plate. It was found that the model built could accurately calculate the variations of flyer plate velocity and Al reaction degree over time. In addition, how physical parameters including detonation product pressure and temperature varied with time and axial positions was identified. The action time of the positive pressure after the detonation of aluminized explosives was found prolonged and the downtrend of the temperature was

关键词： Aluminized explosive Flyer plate experiment Quasi-isentropic theoretical model Al reaction Driving characteristics

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行星式球磨颗粒流场分布与形貌变化规律

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兵工学报 2022年第4期43卷 876-891页

作者：李旭刘彦安丰江王虹富许迎亮北京理工大学机电学院北京100081

基于离散元模拟探究行星式球磨过程中颗粒流场分布,统计球磨过程中磨球整体与颗粒群碰撞的相对速度分布规律,进而提取单个磨球的碰撞场景,模拟多层颗粒的撞击场并研究层间压应力分布;开展铝与聚四氟乙烯混合物料颗粒及纯铝粉的行星式球... 详细信息

基于离散元模拟探究行星式球磨过程中颗粒流场分布,统计球磨过程中磨球整体与颗粒群碰撞的相对速度分布规律,进而提取单个磨球的碰撞场景,模拟多层颗粒的撞击场并研究层间压应力分布;开展铝与聚四氟乙烯混合物料颗粒及纯铝粉的行星式球磨试验,记录不同时刻颗粒群平均粒径,用以表征颗粒形貌变化,进一步提出基于颗粒群破碎概率与分形数的颗粒群平均粒径变化理论。研究结果表明:球磨时磨球整体与颗粒群碰撞中的低速碰撞占主体,仅1%的碰撞为归一化速度ξ>0.33的相对高速碰撞,威布尔分布能良好表征碰撞相对速度的分布规律;对于多层颗粒的撞击场,随着磨球撞击速度提高,其层间压应力分布趋向于哑铃形或葫芦形分布;颗粒群平均粒径关于球磨时间呈指数衰减规律。

关键词：行星式球磨颗粒流场分布压应力场形貌变化

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双装药同步爆炸钢筋混凝土梁毁伤效应

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兵工学报 2023年第12期44卷 3719-3732页

作者：许迎亮刘彦闫俊伯白帆于浩李旭王虹富北京理工大学爆炸科学与技术国家重点试验室北京100081 北京理工大学重庆创新中心重庆401120 中国兵器科学院北京100089

为研究双装药同步爆炸载荷对钢筋混凝土梁的毁伤效应,开展了钢筋混凝土梁双装药同步爆炸试验,得到了混凝土梁的破坏特征和位移响应。基于试验结果,利用有限元仿真软件建立了相应的钢筋混凝土梁双装药同步爆炸仿真模型,考虑了简支边界条... 详细信息

为研究双装药同步爆炸载荷对钢筋混凝土梁的毁伤效应,开展了钢筋混凝土梁双装药同步爆炸试验,得到了混凝土梁的破坏特征和位移响应。基于试验结果,利用有限元仿真软件建立了相应的钢筋混凝土梁双装药同步爆炸仿真模型,考虑了简支边界条件的影响。通过对比混凝土梁的局部破坏特征以及最大位移响应,验证了仿真模型的可靠性。基于此,进一步研究双装药同步爆炸时装药间距和炸高对混凝土梁破坏特征和位移响应的影响。此外,对比相同炸高下双装药和总质量相同的单个装药对混凝土梁的毁伤效应。研究结果表明:随着装药间距的增大,混凝土梁的破坏模式由局部破坏逐渐变为冲切破坏。由于双装药同步爆炸冲击波叠加增强效应的影响,混凝土梁位移响应和迎爆面破坏范围随着装药间距的增加呈现先增大、后减小的变化趋势。对于破坏模式,双装药作用下混凝土梁的局部破坏比等质量单装药作用时更加均匀,破坏范围更大,尤其是对迎爆面的破坏;对于位移响应,存在一个关于装药间距的区间范围,在该范围内双装药作用下混凝土梁的位移响应大于等质量单装药作用下混凝土梁的位移响应:炸高越小,该区间范围越大,装药质量越大,该区间范围越大。

关键词：双装药同步爆炸混凝土梁叠加冲击波装药间距毁伤范围

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Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing Liu Bing xu Zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by *** understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were *** rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global *** δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,*** end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate *** isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid *** on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely *** the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier ***,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

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基于区块划分并行填充的混凝土细观建模方法及其在弹体超高速侵彻中应用

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兵工学报 2023年第12期44卷 3543-3561页

作者：李旭刘彦闫俊伯时振清王虹富许迎亮黄风雷北京理工大学爆炸科学与技术国家重点实验室北京100081 北京理工大学重庆创新中心重庆401120 中国兵器科学研究院北京100089

基于超高速深侵彻细观模拟中对大型复杂模型快速生成的需要,提出一种基于材料属性关联和区块划分并行填充的混凝土细观模型构建方法,并基于界面过渡区(ITZ)表征方法的差异化建模验证其在准静态与超高速侵彻条件下的表征能力。研究结果表... 详细信息

基于超高速深侵彻细观模拟中对大型复杂模型快速生成的需要,提出一种基于材料属性关联和区块划分并行填充的混凝土细观模型构建方法,并基于界面过渡区(ITZ)表征方法的差异化建模验证其在准静态与超高速侵彻条件下的表征能力。研究结果表明:该加速建模方法在建模效率与精确度上具备显著优势,可实现大型复杂形状混凝土构件的快速建模和细观组分的精确占比投放。进一步总结了ITZ实体单元法、无ITZ法和粘结失效接触法3种不同ITZ表征方法的适用条件与材料参数初判标准,不同于准静态模拟中的普遍优越性,超高速侵彻模拟中ITZ实体单元法对侵深与弹坑尺寸的预测效果最佳(偏差小于10%),粘结失效接触法则因未引入应变率效应与易出现数值不稳定现象而在弹坑尺寸预测中表现相对最差。此外,细观模拟中对侵蚀弹体的响应计算和形貌表征与已建立的头部演化高速侵彻模型表现出高度一致性。该研究成果可解决工程实际中的大型复杂细观靶体建模困难,并为超高速深侵彻的细观尺度机理探究提供基础。

关键词：细观模拟并行加速界面表征超高速侵彻

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Laboratory evaluation of high-friction thin overlays for pavement preservation

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 936-948页

作者： Ouming xu Rentao xu Lintong JIN School of Highway Chang’an UniversityXi’an 710064China School of Materials Science and Engineering Chang’an UniversityXi’an 710061China

Traditional asphalt concrete(AC)and stone matrix asphalt(SMA),which are used as thin asphalt overlays,are common maintenance strategies to enhancing ride quality,skid resistance,and ***,several studies have used a novel asphalt mixture known as a high-friction thin overlay(HFTO)to improve surface ***,it remains uncertain whether the laboratory properties of HFTO differ significantly from those of conventional *** study aims to evaluate the laboratory properties of HFTO mixtures and compare them with those of AC and *** mixtures with nominal maximum size of 9.5 mm were produced in the laboratory,and performance tests were conducted,including wheel tracking test,low temperature flexural creep test,moisture susceptibility test,Cantabro Abrasion Test,Marshall Test,sand patch test,British pendulum test,and indoor tire-rollingdown *** results showed that the HFTO exhibited a lower tire/pavement noise than the AC and ***,HFTO had superior high-temperature stability,larger macro texture,and higher skid resistance in comparison to those of AC,but lower than those of ***,HFTO mixtures may be considered a suitable replacement for traditional AC mixtures in regions where skid resistance and noise reduction are concerns.

关键词： road engineering pavement maintenance high friction thin overlay performance skid resistance tire/pavement noise

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Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu Hua Kuang Chuanlai xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health *** this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically ***,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was *** DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of ***,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and ***,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

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Granting strength to aerogel fibers through encapsulation

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Science China Materials 2024年第4期67卷 1365-1366页

作者： Wenhui xu Department of Basic Chemistry School of PharmacyJiangxi University of Chinese MedicineNanchang 330004China

Aerogel fibers, distinguished by their lightweight nature, pronounced porosity, large surface area, and superior thermal insulation properties, have diversified applications in thermal management, energy devices, and environmental remediation[1]. However, compared with monolithic ones, these fibershaped aerogels exhibit limited mechanical strength and resilience due to their one-dimensional small size.

关键词： strength fibers thermal

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