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Frontiers of Earth Science 2018年第3期12卷 600-610页

作者： Yang PU jihong jia Jicheng CAO School of Geographical Sciences Nanjing University of Information Science & Technology Nanjing 210044 China

As part of an investigation of the sources of aliphatic hydrocarbons to the sediments of alpine Lake Ximencuo, leaves of the eight dominant vascular plants were collected and their hydrocarbon contents were analyzed. A series of unsaturated aliphatic hydrocarbons were identified in the plant leaves; in particular, Festuca sp. contain a series of n-alkadienes that have rarely been reported in previous studies. The comparison of n-alkane proxies （ACL27 33, ACLT, Paq, and CPI） and δ13Corg among plant leaves, surface soils, and lake sediments suggests that organic proxies have been altered to varying degrees during the transport and burial process of organic materials. It is believed that microbial reworking and source changes have great impacts on organic proxies in the alpine lake system. In addition, the cluster analysis for plant leaves depending on n-alkane compositions and the ACLT proxy generates similar results. Accordingly, we postulate that the average chain length of plant waxes might be a potential indicator of plant classification in regions such as the Qinghai-Tibet Plateau.

关键词： plant leaves alpine lake n-alkanes n-alka-dienes Qinghai-Tibet Plateau (QTP)

“23·7”京津冀地区暴雨洪水与土壤侵蚀调查——以河北省邢台市临城县为例

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水土保持通报 2024年第2期44卷 155-166,214页

作者：李天毅戴宁丛佩娟陈恒昌贾继宏李扬贵欣瑞水利部水土保持监测中心北京100053 西安理工大学省部共建西北旱区生态水利国家重点实验室陕西西安710048 河北省临城县水务局河北临城054399

[目的]开展“23·7”(20230729—0801)京津冀地区暴雨洪水过程及水土保持调查工作,分析小流域的暴雨洪水过程以及暴雨所造成的土壤侵蚀状况,为水土保持决策提供科学支撑。[方法]采用野外调查的方法对河北省临城县皇迷东沟和梁家庄西沟... 详细信息

[目的]开展“23·7”(20230729—0801)京津冀地区暴雨洪水过程及水土保持调查工作,分析小流域的暴雨洪水过程以及暴雨所造成的土壤侵蚀状况,为水土保持决策提供科学支撑。[方法]采用野外调查的方法对河北省临城县皇迷东沟和梁家庄西沟开展洪痕测量调查并计算洪峰流量模数,分析暴雨洪水对小流域造成的侵蚀危害。[结果]①该次降雨持续时间长、雨强大。梁家庄西沟和皇迷东沟流域累计雨量分别达到1008.5和613.6 mm。②按洪痕法调查推算了洪峰流量,皇迷东沟、梁家庄西沟小流域洪峰流量模数为10.80和36.07 m^(3)/(s·km^(2))。坡度和水土保持措施是影响洪峰流量的主要因素。较大的坡度会使洪峰流量变大,而完善的水土保持措施可以起到有效的削峰作用。③调查小流域位于泜河流域上游,是该次暴雨中心和洪水的主要产流区,小流域洪峰流量模数大于下游水文站洪峰流量模数。④梁家庄西沟的侵蚀情况比皇迷东沟严重,主要原因是皇迷东沟的果园、梯田和谷坊的面积比例大于梁家庄西沟,皇迷东沟的平均坡度小于梁家庄西沟且梁家庄雨量站的降雨量峰值持续时间更长。[结论]良好的水土保持措施可以有效减少洪峰流量以及侵蚀现象的发生。实施水土保持措施是必要且有效的。应该进一步完善梯田、台地谷坊的建设。

关键词：极端暴雨暴雨调查洪峰流量模数土地利用类型水土保持措施京津冀地区

广西壮族自治区西部地区β-地中海贫血基因检测结果分析

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中华地方病学杂志 2024年第2期43卷 104-112页

作者：农雪娟黄瑜贾吉宏雷茗许桂丹韦武均常正义谢丽秋梁菊华王春芳右江民族医学院附属医院检验科百色533000

目的了解广西壮族自治区(简称广西)西部地区β-地中海贫血(简称地贫)的阳性检出率和主要基因型。方法选择2013年1月至2019年12月在右江民族医学院附属医院进行地贫基因检测的26189例受检者作为研究对象,回顾性分析其外周血样本地贫基因... 详细信息

目的了解广西壮族自治区(简称广西)西部地区β-地中海贫血(简称地贫)的阳性检出率和主要基因型。方法选择2013年1月至2019年12月在右江民族医学院附属医院进行地贫基因检测的26189例受检者作为研究对象,回顾性分析其外周血样本地贫基因检测结果,通过跨越断裂点PCR(Gap-PCR)法和DNA芯片反向点杂交(RDB)技术检测我国常见的7种α-地贫和17种β-地贫基因型,对常规基因型未检出的疑似β-地贫患者进行缺失型基因检测(Gap-PCR法),对疑似罕见β-地贫患者进行基因高通量测序(Sanger法)。结果26189例受检者中,确诊β-地贫4495例,阳性检出率为17.16%。共检出20种6177个β-地贫等位基因,主要为CD17(2712个,43.90%)和CD41-42(2240个,36.26%),并见7种罕见等位基因:^(G)γ^(+)(^(A)γδβ)^(0)、SEA-HPFH、Hb New York、Hb G-Taipei、Hb Hezhou、Hb G-Coushatta及IVS-Ⅱ-81。4495例β-地贫患者中,杂合子3903例(86.83%),双重杂合子273例(6.07%),纯合子319例(7.10%)。β-地贫患者共检出48种基因型,常见的2种基因型分别为CD17/β^(N)(1890例,42.05%)和CD41-42/β^(N)(1212例,26.96%),共占69.01%(3102/4495);7种罕见基因型分别为^(G)γ^(+)(^(A)γδβ)^(0)/β^(N)(3例),Hb New York/β^(N)(3例),Hb G-Taipei/β^(N)(2例),SEA-HPFH/β^(N)、Hb Hezhou/β^(N)、Hb G-Coushatta/β^(N)、IVS-Ⅱ-81/β^(N)(各1例)。共检出αβ复合地贫1041例(3.97%,1041/26189),涉及116种复合基因型,以--^(SEA)/αα复合CD17/β^(N)为主(144例,13.83%),其次为-α^(3.7)/αα复合CD17/β^(N)(112例,10.76%)。结论广西西部地区是β-地贫高发区,基因型以CD17/β^(N)及CD41-42/β^(N)为主,变异谱复杂多样,基因型丰富。

关键词：地中海贫血基因型构成比

Study of the Ballistic Impact Behavior of Protective Multi-Layer Composite Armor

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 171-199页

作者： Dongsheng jia Yingjie Xu Liangdi Wang jihong Zhu Weihong Zhang State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an710072China

The abalone shell,a composite material whose cross-section is composed of inorganic and organic layers,has high strength and *** by the abalone shell,several multi-layer composite plates with different layer sequences and thicknesses are studied as bullet-proof material in this *** investigate the ballistic performance of this multi-layer structure,the complete characterization model and related material parameters of large deformation,failure and fracture ofAl_(2)O_(3)ceramics andCarbon Fiber Reinforced Polymer(CFRP)are ***,3D finite element models of the proposed composite plates with different layer sequences and thicknesses impacted by a 12.7 mm armor-piercing incendiary(API)are built using Abaqus to predict *** simulation results show that the CFRP/Al2O3 ceramic/Ultrahigh Molecular Weight Polyethylene(UHMWPE)/CFRP(1 mm/4 mm/4 mm/1 mm)composite is the optimized stack of *** simulation results under specified layer sequence and thickness have a reasonable correlation with the experimental results and reflect the failure and fracture of the multi-layer composite protective armor.

关键词： Protective armor composite bionic design structure design mechanical property

Implications of stalagmite density for past climate change:An example from stalagmite growth during the last deglaciation from Wanxiang Cave,western Loess Plateau

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Chinese Science Bulletin 2010年第34期55卷 3936-3943页

作者： ZHANG DeZhong ZHANG PingZhong SANG WenCui CHENG Hai WU XiuPing YUAN Ye BAI YiJun WANG jiangLin jia jihong Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Institute of Global Environmental Change Xi'an Jiaotong University Xi'an 710049 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA

The density of a stalagmite(WX42A)from Wanxiang Cave,Wudu County,Gansu Province,China,in the western margin of the Asian summer monsoon region,presents regular fluctuations in different deposition periods during the last *** long timescales,high-precision 230Th dating and high-resolution stalagmite density data indicate that the density-time series between 17644 a BP and 12758 a BP is quite similar to the stalagmite δ18O record which reflects Asian monsoon ***/weakening(lighter/heavier stalagmite δ18O values)of the Asian monsoon is accompanied by increase/decrease in stalagmite *** short timescales,decrease in stalagmite density correlates to monsoon-retreat events such as the Inter-AllerФd Cold Period(IACP),Older Dryas(OD)and Inter-BФlling Cold Period(IBCP).Generally,this kind of decrease in stalagmite density reflects precipitation decrease with weakening of the Asian monsoon,which in turn slows cave dripwater rate and decreases crystal nuclei,leading to enlargement of calcite crystals,weakened biological activity and decreased soil pCO2 which increases the abundance of impure detrital materials in ***,during the period of large amplitude reduction of precipitation and biological activity which resulted from extreme monsoon-retreat events,temperature variation would dominate fluctuation of stalagmite *** example,stalagmite density increased suddenly when temperature dropped suddenly in the north Atlantic during Heinrich event 1(H-1).This may be caused by low seepage water temperature,more dissolved calcium carbonate,compact regular crystals forming under higher supersaturation,leading to the stalagmite increased *** density fluctuation sensitively recorded stalagmite growth history and environment,demonstrating that stalagmite density can be used as a proxy for paleoclimatic research.

关键词：石笋记录记录密度黄土高原西部末次冰消期 Heinrich事件气候变化笋生长方解石晶体

Local resonance metamaterial-based integrated design for suppressing longitudinal and transverse waves in fluid-conveying pipes

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1821-1840页

作者： Donghai HAN Qi jia Yuanyu GAO Qiduo JIN Xin FANG jihong WEN Dianlong YU Laboratory of Science and Technology on Integrated Logistics Support National University of Defense Technology College of Intelligence Science and Technology National University of Defense Technology

To solve the problem of low broadband multi-directional vibration control of fluid-conveying pipes, a novel metamaterial periodic structure with multi-directional wide bandgaps is proposed. First, an integrated design method is proposed for the longitudinal and transverse wave control of fluid-conveying pipes, and a novel periodic structure unit model is constructed for vibration reduction. Based on the bandgap vibration reduction mechanism of the acoustic metamaterial periodic structure, the material parameters,structural parameters, and the arrangement interval of the periodic structure unit are optimized. The finite element method(FEM) is used to predict the vibration transmission characteristics of the fluid-conveying pipe installed with the vibration reduction periodic structure. Then, the wave/spectrum element method(WSEM) and experimental test are used to verify the calculated results above. Lastly, the vibration attenuation characteristics of the structure under different conditions, such as rubber material parameters, mass ring material, and fluid-structure coupling effect, are analyzed. The results show that the structure can produce a complete bandgap of 46 Hz–75 Hz in the low-frequency band below 100 Hz, which can effectively suppress the low broadband vibration of the fluidconveying pipe. In addition, a high damping rubber material is used in the design of the periodic structure unit, which realizes the effective suppression of each formant peak of the pipe, and improves the vibration reduction effect of the fluid-conveying pipe. Meanwhile, the structure has the effect of suppressing both bending vibration and longitudinal vibration, and effectively inhibits the transmission of transverse waves and longitudinal waves in the pipe. The research results provide a reference for the application of acoustic metamaterials in the multi-directional vibration control of fluid-conveying pipes.

关键词： 70J10 70J30 97M10 acoustic metamaterial fluid-conveying pipe local resonance multi-directional vibration reduction O326

An origami shield with supporting frame structures optimized by a feature-driven topology optimization method

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Defence Technology（防务技术） 2024年第1期31卷 447-456页

作者： Dongsheng jia Pengcheng Feng Liangdi Wang Longcan Chen Jun Wang jihong Zhu Yingjie Xu Weihong Zhang State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi'an710072China

In this paper,the design,manufacture and testing of an origami protective shield with a supporting frame structure are *** consists of an origami shield surface and a deployable supporting frame structure that needs to be portable and sufficiently ***,for the design of the shield surface,a threestage origami crease pattern is developed to reduce the shield size in the folded *** shield surface consists of several stiff modular panels and layered with flexible *** modular panels are made of a multi-layer composite where a ceramic layer is made of small pieces to improve durability as those small pieces enable restriction of crack ***,the supporting frame structure is designed as a chain-of-bars structure in order to fold into a highly compact state as a bundle of bars and deploy in ***,a feature-driven topology structural optimization method preserving component sequence is developed where the inter-dependence of sub-structures is taken into account.A bar with semi-circular ends is used as a basic design *** positions of the bar’s end points are treated as design variables and the width of the bars is kept ***,a constraint on the total length of the chain of bars is ***,the modular panels made of multi-layer composite and the full-scale prototype of the origami shield are fabricated and tested to verify the bullet-proof performance.

关键词： Origami Deployable structure Structure design Shield Composite materials

Asian summer monsoon precipitation recorded by stalagmite oxygen isotopic composition in the western Loess Plateau during AD1875―2003 and its linkage with ocean-atmosphere system

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Chinese Science Bulletin 2008年第13期53卷 2041-2049页

作者： LIU JingHua ZHANG PingZhong CHENG Hai CHEN FaHu YANG XunLin ZHANG DeZhong ZHOU Jing jia jihong AN ChunLei SANG WenCui Kathleen R. JOHNSON Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA School of Geographical Sciences Southwest University Chongqing 400715 China Department of Earth System Science University of California Irvine CA 92697 USA

Based on 5 high-precision 230Th dates and 103 stable oxygen isotope ratios (δ18O) obtained from the top 16 mm of a stalagmite collected from Wanxiang Cave,Wudu,Gansu,variation of monsoonal precipita-tion in the modern Asian Monsoon (AM) marginal zone over the past 100 years was reconstructed. Comparison of the speleothem δ18O record with instrumental precipitation data at Wudu in the past 50 years indicates a high parallelism between the two curves,suggesting that the speleothem δ18O is a good proxy for the AM strength and associated precipitation,controlled by "amount effect" of the pre-cipitation. Variation of the monsoonal precipitation during the past 100 years can be divided into three stages,increasing from AD 1875 to 1900,then decreasing from AD 1901 to 1946,and increasing again thereafter. This variation is quite similar to that of the Drought/Flooding index archived from Chinese historical documents. This speleothem-derived AM record shows a close association with the Pacific Decadal Oscillation (PDO) between AD 1875 and 1977,with higher monsoonal precipitation corre-sponding to cold PDO phase and vice versa at decadal timescale. The monsoonal precipitation varia-tion is out of phase with the PDO after AD 1977,probably resulting from the decadal climate jump in the north Pacific occurring at around AD 1976/77. These results demonstrate a strong linkage between the AM and associated precipitation and the Pacific Ocean via ocean/atmosphere interaction. This rela-tionship will aid to forecast future hydrological cycle for the AM monsoon region,and to improve forecasting potential of climatic model with observation data from cave.

关键词：石笋同位素季风降水