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Earthquake Science 2018年第2期31卷 92-99页

作者： Zengxi Ge Yi Luo yuyan ma Rushan Wu School of Earth and Space Sciences Peking University IGPP University of California

In this paper, we developed the theory and algorithm of an elastic one-way boundary element method（BEM） and a corresponding hybrid elastic thin-slab propagator for earth media with sharp boundaries between strong contrast media. This approach can takes the advantage of accurate boundary condition of BEM and completely overcomes the weak contrast limitation of the perturbationtheory based one-way operator approach. The one-way BEM is a smooth boundary approximation, which avoids huge matrix operations in exact full BEM. In addition, the one-way BEM can model the primary-only transmitted and reflected waves and therefore is a valuable tool in elastic imaging and inversion. Through numerical tests for some simple models,we proved the validity and efficiency of the proposed method.

关键词： boundary element method thin slab one-way wave propagator

Microstructure and magnetic fabric in the Shuanghe pluton:A synkinematic granite in Eastern Dabie Mountains,China

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Science China Earth Sciences 2004年第10期47卷 912-919页

作者： YANG Kunguang LIU Qiang LIU yuyan ma Changqian XU Yajun YANG Kuifeng Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Strain analyses for the Shuanghe pluton show that the main strain planes suffered distinct deformation. The main strain value (XZ) is up to 1.59–2.18, and the value of Flinn index (K) ranges from 0.11 to 0.82. Anisotropy of magnetic susceptibility (AMS) measurements reveal that the orientations of the magnetic foliation and lineation gently dip SE, consistent with the macroscopic foliation of the pluton. The value of anisotropy degree (P) ranges from 1.109 to 1.639, and the shape parameter (T) from 0.079 to 0.534. These studies prove that the pluton was deformed under strong compression. Quartz c-axis textures, defined by monoclinic or triclinic asymmetry, usually developed the high maxima paralleling the b-axis, which is defined by the prismatic slip (1010) under the high temperature. These fabrics are quite different from those developed in the high-ultrahigh pressure rocks (UHP) which were captured in the pluton or country rocks. It is concluded that the Shuanghe pluton emplaced under regional compression slightly after the formation of UHP, and it is characterized by synkinematic granitic deformation.

关键词： strain analysis, anisotropy of magnetic susceptibility (AMS), quartz c-axis fabric, synkinematic granite,Dabie Mountains.

PIM-1 as an artificial solid electrolyte interphase for stable lithium metal anode in high-performance batteries

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Journal of Energy Chemistry 2020年第3期29卷 83-90页

作者： Qiuli Yang Wenli Li Chen Dong yuyan ma Yuxin Yin Qibing Wu Zhitao Xu Wei ma Cheng Fan Kening Sun Beijing Key Laboratory for Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina

Lithium metal anode is a promising electrode with high theoretical specific capacity and low electrode ***,its unstable interface and low Coulombic efficiency,resulting from the dendritic growth of lithium,limits its commercial ***-1(PIM:polymer of intrinsic microporosity),which is a polymer with abundant micropores,exhibits high rigidity and flexibility with contorted spirocenters in the backbone,and is an ideal candidate for artificial solid electrolyte interphases(SEI).In this work,a PIM-1 membrane was synthesized and fabricated as a protective membrane on the surface of an electrode to facilitate the uniform flux of Li ions and act as a stable interface for the lithium plating/stripping ***-like lithium with rounded edges was observed under the PIM-1 *** Li@PIM-1 electrode delivered a high average Coulombic efficiency(99.7%),excellent cyclability(80%capacity retention rate after 600 cycles at 1 C),and superior rate capability(125.3 m Ah g-1 at 10 C).Electrochemical impedance spectrum(EIS)showed that the PIM-1 membrane could lower the diffusion rate of Li+significantly and change the rate-determining step from charge transfer to Li+***,the PIM-1 membrane is proven to act as an artificial SEI to facilitate uniform and stable deposition of lithium,in favor of obtaining a compact and dense Li-plating *** work extends the application of PIMs in the field of lithium batteries and provides ideas for the construction of artificial SEI.

关键词： Lithium metal anodes Artificial solid electrolyte interphase PIM-1 Diffusion-limited

A homogeneous and mechanically stable artificial diffusion layer using rigid-flexible hybrid polymer for high-performance lithium metal batteries

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Journal of Energy Chemistry 2023年第1期76卷 631-638,I0015页

作者： Zhenkang Lin yuyan ma Wei Wang Yu He Menghao Wang Jun Tang Cheng Fan Kening Sun Beijing Key Laboratory for Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Artificial solid electrolyte interphase(SEI) is promising to inhibit uncontrollable lithium dendrites and enable long cycling stability for lithium metal batteries. However, the essential mechanical stability is limited since organic layers generally have low modulus whereas intrinsic brittleness for inorganic ones remains a great concern. Polymer-based SEIs with rigid and flexible chains in adequate mechanical properties are supposed to address this issue. Herein, a homogeneous and mechanically stable diffusion layer is achieved by blending rigid chains of polyphenylene sulfone(PPSU) with flexible chains of poly(vinylidene fluoride)(PVDF) in a hybrid membrane, enabling uniform diffusion and stabilizing the lithium metal anode. The Li||Cu cell with the protected electrode exhibits a long lifetime more than 450 cycles(0.5 m A cm^(-2), 1.0 m A h cm^(-2))(fourfold longer than the control group) with higher average Coulombic efficiency of 98.7%. Enhanced performances are also observed at Li||Li and full cell configurations. The improved performances are attributed to the controlled morphology and stable interphase, according to scanning electron microscopy(SEM) and electrochemical impedance. This research advances the idea of uniform lithium plating and provides a new insight on how to create a homogeneous and mechanically stable diffusion layer using rigid-flexible polymers.

关键词： Lithium metal battery Lithium dendrite Uniform diffusion Rigid-flexible artificial layer Electrochemical impedance

Investigation of polysulfone film on high-performance anode with stabilized electrolyte/electrode interface for lithium batteries

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Journal of Energy Chemistry 2020年第3期29卷 49-55页

作者： yuyan ma Chen Dong Qiuli Yang Yuxin Yin Xiaoping Bai Shuying Zhen Cheng Fan Kening Sun Beijing Key Laboratory for Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Yinlong Energy Co. Ltd.Zhuhai 519040GuangdongChina Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage ***,challenges still stand in protecting lithium metal from spontaneous reactions with electrolytes and preventing the dendritic propagation,both of which would lead to undesirable decrease in Coulombic ***(PSf)membrane with high rigidity and free-volume cavities of approximately 0.3 nm was employed to provide a stable interface on the surface of anodic *** isotropic channels were constructed by the interconnected and uniformly distributed free volumes in the polymer matrix,and were expected to be swelled by solvent molecules and anions of lithium salt and to allow Li+ions to pass through onto the electrode *** a result,dendrite-free morphology of deposited lithium was *** stabilized interface arose from the PSf film was verified by the promoted performances of Cu|Li cells and steady voltage polarization of Li|Li *** full cell with PSf coated anode exhibited excellent cyclability(85%capacity retention rate over 400 cycles at 1C)and an outstanding rate capability(117 m Ah g-1 at 5C).The beneficial performances were further verified by the EIS *** work provides a new strategic idea to settle the dendritic problems of Li metal anodes.

关键词： Lithium metal Electrolyte/electrode interface Dendrite-free Polysulfone Free volume

Antibody Levels and Infection Status of Pertussis in the Population under Pertussis Resurgence in Guangxi in 2018:A Cross-Sectional Survey

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Biomedical and Environmental Sciences 2024年第6期37卷 628-638页

作者： Liang Liang Qiuyun Deng Lili Deng Jinghang Wei Shiyi Chen Yizhi Wei yuyan ma Yue Qin Wei Liu Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention Nanning 530028GuangxiChina

Objective Pertussis cases have increased markedly since 2018 in *** aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident *** A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay(ELISA).Results Of the collected samples,1,833(17.94%)tested positive for anti-pertussis IgG,with the median concentration of 16.06 IU/*** levelmain factors contributing to the resurgence of pertussis in *** addition,the prevalence of pertussis is relatively high in Guangxi,and its incidence is seriously underestimated,especially in adolescents and adults.

关键词： Pertussis resurgence Anti-pertussis IgG Anti-pertussis toxin IgG Antibody level Infection status

利用SS前驱波研究纳斯卡-南美俯冲带周边上地幔间断面起伏及其动力学意义

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北京大学学报（自然科学版） 2018年第6期54卷 1186-1194页

作者：马宇岩盖增喜北京大学地球与空间科学学院北京100871

利用USArray的远震记录资料,对1万多条地震记录的SS前驱波进行共反射点叠加分析(叠加范围是半径为5°的球冠),得到纳斯卡板块南部及南美板块西部(120°W—60°W,30°S—5°N)上地幔间断面的起伏形态。由于数据很好地覆盖了研究区域,叠... 详细信息

利用USArray的远震记录资料,对1万多条地震记录的SS前驱波进行共反射点叠加分析(叠加范围是半径为5°的球冠),得到纳斯卡板块南部及南美板块西部(120°W—60°W,30°S—5°N)上地幔间断面的起伏形态。由于数据很好地覆盖了研究区域,叠加范围更小,因此比以往的结果具有更高的空间分辨率。在Galapagos,Easter和SanFelix这3个热点下方观测到的间断面起伏形态符合地幔深部存在高温异常的假设。还观测到:在东太平洋洋隆南段下方, 410 km间断面深度增加;在俯冲带下方, 410 km和660 km间断面深度增加。

关键词：上地幔间断面地幔过渡带热点俯冲板块东太平洋洋隆南段

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新型冠状病毒感染疫情期孕产妇管理建议

山东大学学报（医学版） 2020年第3期58卷 38-43页

作者：马玉燕山东大学齐鲁医院妇产科山东济南250012

2019冠状病毒病(COVID-19)是一种具有高度传染性的疾病,人群普遍易感,由于妊娠期的免疫特点,孕产妇为易感人群,针对2019冠状病毒病尚无特异性治疗方案,且无疫苗可用于预防,一旦孕产妇暴发感染危害严重,因此疫情期间应加强对孕产妇的指... 详细信息

2019冠状病毒病(COVID-19)是一种具有高度传染性的疾病,人群普遍易感,由于妊娠期的免疫特点,孕产妇为易感人群,针对2019冠状病毒病尚无特异性治疗方案,且无疫苗可用于预防,一旦孕产妇暴发感染危害严重,因此疫情期间应加强对孕产妇的指导和管理,提供切实可行的孕产妇保健建议,预防妊娠期感染,对获得良好的母儿结局非常重要.

关键词：孕妇新型冠状病毒预防互联网产检

Measurement of the absorption spectrum of H_2O^+ in the visible region

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Chinese Science Bulletin 2001年第22期46卷 1866-1869页

作者： ZHUANG Hua, CHEN Yangqin, Jl Wenhai,WU Shenghai, Bl Zhiyi, LIU yuyan & ma LongshengKey Laboratory of Optical and magnetic Resonance Spectroscopy, Department of Physics, East China Normal University, Shanghai 200062, China Key Laboratory of Optical and magnetic Resonance Spectroscopy Department of Physics East China Normal University Shanghai China

Together with the 74 lines belonging to (0,9,0)-(0,0,0) band, the high-resolution absorption spectrum ofH2O+ A2A1-X2B1 system was observed in the visibleregion of 16680-17300 cm-1 using optical heterodyne magnetic rotation enhanced velocity modulation spectroscopy for the first time, which verifies the high sensitivity and high signal to noise ratio (S/N) of this technique.

关键词： H2O+ optical heterodyne technique magnetic rotation spectroscopy velocity modulation spectroscopy.