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Penetration resistance of Al_(2)O_(3) ceramic-ultra-high molecular weight polyethylene(UHMWPE)composite armor:Experimental and numerical investigations

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Theoretical & Applied Mechanics Letters 2024年第5期14卷 346-359页

作者： Wencheng Lu Yiding Wu Minghui Ma yilei yu Xuan Zhou Guangfa Gao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

To enhance the protective performance of ceramic composite armor,ballistic penetration experiments were conducted on Al_(2)O_(3) ceramic-ultra-high molecular weight polyethylene(UHMWPE)composite armor with different thickness *** damage and failure modes of hard projectiles and ceramic-fiber composite targets were *** recovered projectiles and ceramic fragments were sieved and weighed at multiple stages,revealing a positive correlation between the degree of fragmentation of the projectiles and ceramics and the overall ballistic resistance of the composite *** simulations were performed using the LS-DYNA finite element software,and the simulation results showed high consistency with the experimental results,confirming the validity of the material *** results indicate that the projectile heads primarily exhibited crushing and abrasive *** projectile fragments mainly resulted from tensile and shear stress-induced *** failure modes of the composite targets included the formation of ceramic cones and radial cracks under high-velocity *** UHMWPE laminated plates exhibited interlayer separation caused by tensile waves,permanent plastic deformation of the rear surface bulging,and perforation failure primarily due to shear *** extended numerical simulations,while maintaining the same areal density and configuration of9 mm Al_(2)O_(3) ceramic+12 mm UHMWPE laminated composite armor,the thickness configurations of the Al_(2)O_(3) ceramic and UHMWPE laminated backplates were varied,and various thicknesses of UHMWPE laminates were simulated as the cover layer for the ceramic *** simulation results indicated that the composite armor configuration of 10 mm Al_(2)O_(3) ceramic+8 mm UHMWPE composite armor increased energy absorption by13.48%.When altering the cover layer thickness,a 4 mm UHMWPE+9 mm Al_(2)O_(3)+8 mm UHMWPE composite armor demonstrated a 27.11%improvement in energy abso

关键词： Composite armor Al_(2)O_(3) ceramic UHMWPE laminates Damage and failure modes Ballistic performance Numerical simulation

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Identification of key factors governing chemistry in groundwater near the water course recharged by reclaimed water at Miyun County, Northern China

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Journal of Environmental Sciences 2013年第9期25卷 1754-1763页

作者： yilei yu Xianfang Song Yinghua Zhang Fandong Zheng Ji Liang Dongmei Han Ying Ma Hongmei Bu Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Beijing Hydraulic Research

Reclaimed water was successfully used to recover the dry Chaobai River in Northern China, but groundwater may be polluted. To ensure groundwater protection, it is therefore critical to identify the governing factors of groundwater chemistry. Samples of reclaimed water, river and groundwater were collected monthly at Chaobai River from January to September in 2010. Fifteen water parameters were analyzed. Two kinds of reclaimed water were different in type （Na-Ca-Mg-Cl-HCO3 or Na-Ca-Cl-HCO3 ） and concentration of nitrogen. The ionic concentration and type in river were similar to reclaimed water. Some shallow wells near the river bed had the same type （Na-Ca-Mg-Cl-HCO3 ） and high concentration as reclaimed water, but others were consistent with the deep wells （Ca-Mg-HCO3 ）. Using cluster analysis, the 9 months were divided into two periods （dry and wet seasons）, and all samples were grouped into several spatial clusters, indicating different controlling mechanisms. Principal component analysis and conventional ionic plots showed that calcium, magnesium and bicarbonate were controlled by water-rock interaction in all deep and some shallow wells. This included the dissolution of calcite and carbonate weathering. Sodium, potassium, chloride and sulfate in river and some shallow wells recharged by river were governed by evaporation crystallization and mixing of reclaimed water. But groundwater chemistry was not controlled by precipitation. During the infiltration of reclaimed water, cation exchange took place between （sodium, potassium） and （calcium, magnesium）. Nitrification and denitrification both happened in most shallow groundwater, but only denitrification in deep groundwater.

关键词： reclaimed water groundwater chemistry multivariate analysis Chaobai River water-rock interaction evaporation crystallization cation exchange denitrification

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Impact of reclaimed water in the watercourse of Huai River on groundwater from Chaobai River basin, Northern China

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Frontiers of Structural and Civil Engineering 2017年第4期11卷 643-659页

作者： yilei yu Xianfang SONG Yinghua ZHANG Fandong ZHENG Licai LIU Beijing Key Laboratory of Wetland Services and Restoration Institute of Wetland Research Chinese Academy of Forestry B eijing 100091 China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Beijing Water Science and Technology Institute Beijing 100048 China

Reclaimed water is efficient for replenishing the dry rivers in northern China, but regional groundwater may be at risk from pollution. Therefore, samples of reclaimed water, river water, and groundwater were collected at the Huai River in the Chaobai River basin in 2010. The water chemistry and isotopic compositions of the samples were analyzed in the laboratory. The reclaimed water had stable compositions of water chemistry and isotopes, and the Na. Ca-HCO3. C1 water type. The water chemistry of the river water was consistent with that of the reclaimed water. A June peak of total nitrogen was the prominent characteristic in the shallow groundwater, which also had the Na. Ca-HCO3. C1 water type. However, the water chemistry and isotopes in most of the deep groundwater remained stable, and the water type was Ca-Mg-HCO3. The amount of reclaimed water recharging the groundwater was about 2.5 - 107 m^3/yr. All of the shallow groundwater was impacted by the reclaimed water, with the mixing proportion of reclaimed water ranging from 42% to 80 % in the dry season and from 20% to 86% in the wet season. Only one deep well, with proportions of 67% （dry season） and 28% （wet season）, was impacted. TDS, EC, and major ions （Na, K, C1, NHn-N, NO2-N, and NO3-N） were increased in the impacted wells.

关键词： groundwater hydrochemistry Huai River reclaimed water stable isotopes

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Water regime-nitrogen fertilizer incorporation interaction：Field study on methane and nitrous oxide emissions from a rice agroecosystem in Harbin, China

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Journal of Environmental Sciences 2018年第2期30卷 289-297页

作者： Wenjun Dong Jia Guo Lijun Xu Zhifeng Song Jun Zhang Ao Tang Xijuan Zhang Chunxu Leng Youhong Liu Lianmin Wang Lizhi Wang Yang yu Zhongliang Yang yilei yu Ying Meng Yongcai Lai Heilongjiang Academy of Agricultural Sciences Postdoctoral Programme Harbin 150086 China Cultivation and Farming Research Institute Heilongjiang Academy of Agricultural Sciences Harbin 150086 China Northern Japonica Rice Molecular Breeding Joint Research Center Chinese Academy of Sciences Harbin 250086 China Scientific Observing and Experimental Station of Crop Cultivation in Northeast China Ministry of Agriculture Harbin 150086 China Institute of Wetland Research Chinese Academy of Forestry Beijing 100091 China Beijing Key Laboratory of Wetland Services and Restoration Beijing 100091 China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Jilin Academy of Agricultural Sciences ChangchunJilin 130124 China Institute of Crop Science Chinese Academy of Agricultural Sciences Beijing 100081 China Rice Institute of Wuchang Heilongjiang Academy of Agricultural Sciences Wuchang 150229 China

Water regime and nitrogen（N） fertilizer are two important factors impacting greenhouse gases（GHG） emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane（CH4） emission compared with continuous flooding, however,the decrement was far lower than the global average level. The N2O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH4 emissions at low level（75 kg N/ha）. But both CH4 and N2O emissions were uninfluenced at the levels of 150 kg N/ha and 225 kg N/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150 kg N/ha. From our results, we recommended that the intermittent irrigation and 150 kg N/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields.

关键词： Methane(CH4) Nitrous oxide(N2O) Rice ecosystem Cold region Global warming potential

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Enhanced ballistic resistance of SiC ceramic-fiber composite armor:an investigation of fiber laminate backing effects and fragmentation dynamics

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Acta Mechanica Sinica 2024年第11期40卷 37-52页

作者： Wencheng Lu Yiding Wu Minghui Ma yilei yu Xuan Zhou Botong Wang Guangfa Gao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

This study examines the penetration of 12.7 mm armor piercing incendiary projectiles into SiC ceramic-fiber composite target *** observing the recovered projectile and the overall damage morphology of the ceramic-fiber composite target ***,multi-level screening and weighing of the recovered projectile and ceramic fragments revealed that the mass distribution of the projectile and ceramic fragments under different backing structures conforms to a powerlaw *** results indicate that for single laminate as the backing,the fragmentation of the projectile and ceramics is highest when T300 is the *** a T300 transition layer between the SiC ceramic and aramid fibers(Kevlar)or ultra-high molecular weight polyethylene(UHMWPE)increases the fragmentation of the projectile and ceramics,leading to increased energy *** projectile’s head mainly exhibits pulverized abrasive fragmentation,while larger projectile fragments primarily result from shear and tensile stress-induced shear-tensile failure *** primary damage mode of ceramics under high-speed impact is the expansion of ceramic cones and radial *** main form of damage in UHMWPE laminate is interlayer separation caused by tensile waves,permanent plastic deformation at the back protrusion,and perforation failure primarily due to shear *** damage mode of Kevlar laminate is similar to that of UHMWPE,with the distinction being that Kevlar laminate primarily exhibits perforation failure caused by tensile *** fiber T300 laminate damage mainly consists of cross-shaped brittle fractures caused by shear waves.

关键词： 12.7 mm armor piercing incendiary SiC ceramic Fiber composite materials Failure modes Fragment statistics

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Water quality of reclaimed water from treated urban wastewater in Chaobai River Basin,North China

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Chinese Journal of Population,Resources and Environment 2014年第2期12卷 103-109页

作者： yilei yu Xianfang Song Yinghua Zhang Fandong Zheng Licai Liu Institute of Wetland Research Chinese Academy of Forestry Key Laboratory of Water Cycle and Relate Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Beijing Water Science & Technology Institute

The utilization of reclaimed water could be an efficient tool to alleviate water scarcity,especially for dry river ***,it is crucial to monitor water quality to ensure safety to human health and to avoid negative effects on the *** water samples were collected bimonthly from May to November in 2010 in Chaobai River,and the physiochemical parameters were *** main results are as follows:The parameters exceeding the threshold value of the water guidelines are mainly nutrition related to nitrogen and phosphorus,which are known to increase the risk of eutrophication in surface ***,nitrite and nitrate can be detrimental to human *** majority of the parameters have a peaking concentration in May,whereas others either show significant temporal variation over the entire period or remain relatively constant in all four *** analysis shows that some parameters(pH,T and B) have no significant correlation with others,whereas significant positive correlation was found for Sr with EC and TDS,for CI with TDS,for Si02 with TP and for NO3-N with TN and a significant negative correlation between SO4 and *** to principal component analysis,60.108%of the total data is represented by dominant solutes,and the second principal component with a percentage of 31.876 comprises parameters related to *** cluster analysis of parameters identified four groups,which represent different compositions,and samples in May differ from others.

关键词： water quality treated urban wastewater water guidelines multivariate statistical analysis Chaobai River

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关于新疆区域试点太阳能热发电的思考

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太阳能 2019年第6期 16-18页

作者：于益雷国家能源局新疆监管办公室

从青海海西州太阳能热发电示范项目建设与运营的经验出发,思考其对新疆区域太阳能热发电产业高质量、可持续发展的借鉴意义,并得出新疆区域发展太阳能热发电产业的有效途径在于因地制宜、因域施策,政策引导、试点先行,持续跟踪、总结提高。

关键词：新疆太阳能热发电电力思考

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三层组合陶瓷复合装甲的抗侵彻性能及其损伤机制

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兵工学报 2024年第1期45卷 44-57页

作者：余毅磊王晓东任文科高光发南京理工大学机械工程学院江苏南京210094 宁波大学冲击与安全工程教育部重点实验室浙江宁波315211

为了研究相同面密度下Kevlar/SiC-TC4-超高分子量聚乙烯(UHMWPE)复合靶板的复合结构参数对其抗弹性能的影响和失效机理,选用4组不同厚度组合的靶板试样,并使用12.7 mm穿燃弹以相同着靶速度(488 m/s)进行弹道冲击实验。使用扫描电子显微... 详细信息

为了研究相同面密度下Kevlar/SiC-TC4-超高分子量聚乙烯(UHMWPE)复合靶板的复合结构参数对其抗弹性能的影响和失效机理,选用4组不同厚度组合的靶板试样,并使用12.7 mm穿燃弹以相同着靶速度(488 m/s)进行弹道冲击实验。使用扫描电子显微镜(SEM)研究复合装甲板在弹道侵彻下的损伤模式。实验结果表明:在所述实验条件下8 mm+2 mm+10 mm厚度组合的Kevlar/SiC-TC4-UHMWPE复合靶板是最佳的抗侵彻工程应用结构;在同等面密度条件下,将1 mm厚陶瓷替换成同等面密度的TC4钛合金背板(约0.5 mm厚)时,复合装甲板的抗弹道侵彻性能提升了约29.69%,可见钛合金的结构参数对复合装甲板抗弹性能的影响权重大于SiC;钛合金背板面密度的增加不仅增强了对陶瓷的支撑作用,而且增加了弹-靶作用时间,提升了复合靶板的整体防护性能;12.7 mm穿燃弹侵彻后复合装甲板的损伤模式包括SiC碎裂、钛合金背板少量隆起变形及十字形拉伸撕裂损伤、UHMWPE层合纤维背板剪切断裂、层间分离和纤维拉伸;在整体复合装甲的设计中,应将高抗剪材料放置在背板的前几层,将高抗拉材料放置在背板后几层,以充分利用每种材料。

关键词：陶瓷复合装甲抗弹性能损伤机制超高分子量聚乙烯 12.7 mm穿燃弹

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再生水补水后永定河水化学特征及其形成作用

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干旱区资源与环境 2017年第8期31卷 108-115页

作者：于一雷谷洪彪张佳佳中国林业科学研究院湿地研究所湿地生态功能与恢复北京市重点实验室北京100091 防灾科技学院三河065201

北京长期面临干旱和水资源短缺,再生水补水有效恢复了干涸的永定河生态系统,但亟需加强对再生水水质的研究,为其合理利用和水质安全提供技术支撑。通过对上游水库水及补水后河水的采样、室内外实验和数据分析,结论如下:再生水碱性较高... 详细信息

北京长期面临干旱和水资源短缺,再生水补水有效恢复了干涸的永定河生态系统,但亟需加强对再生水水质的研究,为其合理利用和水质安全提供技术支撑。通过对上游水库水及补水后河水的采样、室内外实验和数据分析,结论如下:再生水碱性较高、富含盐分和氮磷,其中硝态氮为可溶性氮主要形态,而重金属含量极低。除氟离子外,主要离子、氨氮、亚硝态氮、硝态氮和磷酸盐经过园博园湿地净化后明显降低。结合Gibbs图、离子关系及pH-pe关系分析,发现水化学成分主要受蒸发-结晶和水岩作用(主要为白云石、方解石和石膏以及其他碳酸盐和硅酸盐矿物的溶解作用)、钠与钙镁的阳离子交换吸附作用以及硝化作用控制。

关键词：再生水水化学重金属永定河

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不同撞击速度下穿燃弹侵彻陶瓷/铝合金复合靶板时弹芯破碎失效特性研究

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爆炸与冲击 2022年第2期42卷 81-89页

作者：王晓东余毅磊蒋招绣马铭辉高光发南京理工大学机械工程学院江苏南京210094 宁波大学冲击与安全工程教育部重点实验室浙江宁波315211

为了研究12.7 mm穿燃弹以不同速度撞击陶瓷/铝合金复合靶板时弹芯的破碎及失效特性,开展了12.7 mm穿燃弹以434.5~844.6 m/s速度撞击SiC陶瓷/6061T6铝合金复合靶板的弹道试验,分析了弹靶的失效模式。弹芯在侵彻靶板后会产生不同尺寸的碎... 详细信息

为了研究12.7 mm穿燃弹以不同速度撞击陶瓷/铝合金复合靶板时弹芯的破碎及失效特性,开展了12.7 mm穿燃弹以434.5~844.6 m/s速度撞击SiC陶瓷/6061T6铝合金复合靶板的弹道试验,分析了弹靶的失效模式。弹芯在侵彻靶板后会产生不同尺寸的碎片,使用回收箱收集弹芯碎片并用不同孔径筛网对其进行筛分、称重,得到了不同撞击速度下弹芯碎片的质量分布,并对不同部位的弹芯碎片断口形貌进行了宏观和微观观测分析。研究结果表明:背板失效模式为碟形变形-剪切穿孔-花瓣形失效,试验后的弹芯碎片累积质量分布符合Rosin-Rammler幂率分布规律,且随着着靶速度的增大,小质量碎片质量增加;弹芯在冲击过程中等效直径较大碎片(大于8 mm)失效模式为拉伸脆性断裂,而等效直径小于2 mm的碎片上存在局部塑性剪切断裂。

关键词：侵彻 12.7 mm穿燃弹破碎质量分布断裂模式

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