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Chinese Journal of Chemistry 2023年第20期41卷 2597-2603页

作者： Xiaoniu Hou Changfeng li Mengjie li Yuansheng liu Wei Zhu zhenfei li Yunhua Xu School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education)and Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300072 China

Mn-based layered transition metal oxides are promising cathode materials for sodium-ion batteries(SIBs)because of their high theoretical capacities,abundant raw materials,and environment-friendly advantages.However,they often show insufficient performance due to intrinsic issues including poor structural stability and dissolution of Mn^(3+).Atomic doping is an effective way to address these structural degradation issues.Herein,we reported a new synthesis strategy of a Cu-doped layered cathode by directly calcinating a pure metal-organic framework.Benefiting from the unique structure of MOF with atomic-level Cu doping,a homogeneous Cu-doped layered compound P2-Na_(0.674)Cu_(0.01)Mn_(0.99)O_(2) was obtained.The Cu substitution promotes the crystal structural stability and suppresses the dissolution of Mn,thus preventing the structure degradation of the layered cathode materials.A remarkably enhanced cyclability is realized for the Cu-doped cathode compared with that without Cu doping,with 83.8%capacity retention after 300 cycles at 100 mA·g^(-1).Our findings provide new insights into the design of atomic-level doping layered cathode materials constructed by MOFs for high-performance SIBs.

关键词： Metal-organic frameworks Synthesis design/Sodium-ion batteries Layered cathode materials Atomic doping

Transmissive metasurface for multi-channel and full-polarization modulation of electromagnetic wavefronts

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Photonics Research 2023年第2期11卷 245-251页

作者： liNDA SHAO zhenfei li JIAliN FENG JIN ZHANG HONGYU SHI XUDONG BAI WEIREN ZHU Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Information and Communications Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Microelectronics Northwestern Polytechnical UniversityTaicang 215400China

Metasurfaces have great potential for flexible manipulation of electromagnetic wave polarizations and wavefronts.Here, we propose a general method for achieving independent wavefront manipulation in a single polarizationmultiplexing transmissive metasurface. As a proof of concept, we design a transmission-type anisotropic metasurface for independent wavefront manipulation in full-polarization channels. An x-polarized wave transmitted through such a metasurface could be converted into four outgoing beams with delicately designed polarization states that converge to specific positions for holographic imaging. The measured results are in good agreements with simulated ones, verifying the independent wavefront manipulations with arbitrary polarization conversions.Compared with the existing traditional meta-devices with single-polarization modulation, we achieve polarization-multiplexed metasurfaces with mixed polarization and phase control, which can greatly improve the functional richness of the system.

关键词： surface. proof holographic

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关中东部商代遗存的文化因素分析

考古与文物 2024年第2期 89-103页

作者：李振飞郭妍利西北大学文化遗产学院陕西师范大学历史文化学院

本文运用文化因素分析法,将关中东部商代文化遗存分为A类商文化、B类本土文化、C类先周文化、D类北方文化、E类早期巴蜀文化五类文化因素。五类文化因素中前四类最为重要,其从早商到晚商时期的变化反映了本土文化因素的稳步发展、商文... 详细信息

本文运用文化因素分析法,将关中东部商代文化遗存分为A类商文化、B类本土文化、C类先周文化、D类北方文化、E类早期巴蜀文化五类文化因素。五类文化因素中前四类最为重要,其从早商到晚商时期的变化反映了本土文化因素的稳步发展、商文化的日渐淡出、周文化的有力推进、北方文化的持续进入,显示了各支文化对关中东部商代不同时期的关注和经略。

关键词：关中东部商代文化因素分析

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基于大比例地形图动态更新工作的探索与实践

城市勘测 2024年第1期 100-102,108页

作者：吴志华李振飞邱钊合肥市测绘设计研究院有限公司安徽合肥230001 安徽正创信息技术有限公司安徽合肥230051

地形图动态更新是一项基础性测绘工作,是当前地形图图库一体和数据标准化应用的趋势。通过整合相关零星项目地形图成果资料,利用CAD、EPS、FME和ArcMap成图软件,叠加最新遥感影像并结合现场巡查,实现变化图斑从发现到实时更新,以保证地... 详细信息

地形图动态更新是一项基础性测绘工作,是当前地形图图库一体和数据标准化应用的趋势。通过整合相关零星项目地形图成果资料,利用CAD、EPS、FME和ArcMap成图软件,叠加最新遥感影像并结合现场巡查,实现变化图斑从发现到实时更新,以保证地形图现状性的目的。结合各类成图软件的优点,构建空间索引,完成数据转换,做好接边和入库相关工作,是地形图更新和应用的有效实践。

关键词：图库一体空间索引数据转换 FME ArcMap 动态更新

Analysis of microcrystal formation in DS-silicon ingot

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Science China(Technological Sciences) 2011年第6期54卷 1475-1480页

作者： ZHANG ZhiQiang HUANG Qiang HUANG zhenfei li BiWu CHEN Xue Technology Department of Trinasolar Changzhou 213031 China

The DS(directional solidification) polycrystalline silicon ingot is the most important photovoltaic material today,and the conversion efficiency of solar cells is affected by the morphology and organization of the crystal.Uniform grains with larger size are conducive to get high-quality wafer,so improving the cell conversion efficiency.However,grains sizes that are less than 1 mm2 can be observed frequently in the central district of mc-Si ingots,which bring negative effect to the quality of the mc-Si ingot and decrease the electrical performance of wafer.In this paper,we make an attempt to explain the formation mechanism and influence factors of microcrystal in mc-Si ingot with computer simulation technology and theory of component supercooling.It was found that:to avoid production of microcrystal,it's better to increase the value of G/V(V is the growth rate and G is the near-interface temperature gradient),strengthen the melt convection front in the solidification interface and keep a fairly flat solid/melt interface in producing mc-Si ingot.

关键词：多晶硅微晶硅 DS 计算机模拟技术太阳能电池成分凝固界面转换效率

Epigenetic regulation in Wnt signaling

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Epigenetic regulation in Wnt signaling

BMP and Wnt signaling crosstalk during neurogenesis of developing spinal cord

中国生物化学与分子生物学会第十届会员代表大会暨全国学术...

作者： Yingying Jia zhenfei li Fen Nie lin li State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of Sciences

The canonical Wnt signaling pathway controls and regulates many developmental processes through a complex of P-catenin and the HMG-box transcription factors of the LEF1/TCFs family.Many co-activators including histone modification enzymes are recruited into P-catenin·LEF1/ TCFs transcription complex at target gene promoters to facilitate gene transcription.Here we show that two novel

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BMP and Wnt signaling crosstalk during neurogenesis of devel...

第六届国际bHLH转录调控机制研讨会

作者： Zhihui Xie Yongfeng Chen zhenfei li Ye-Guang Chen Francois Guillemot lin li Naihe Jing Laboratory of Molecular Cell Biology State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of Sciences Department of Biological Sciences and Biotechnology Tsinghua University Division of Molecular Neurobiology National Institute for Medical ResearchThe RidgewayMill HillLondon NW7 1 AAUK Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological SciencesChinese Academy of Sciences

＜正＞Proliferation of the neural/neuronal progenitor cells（NPCs） at the ventricular zone of the dorsal spinal cord requires the stimuli of Wnt and BMP.However,how these two signaling pathways are regulated in the N...

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数字贸易例外规则的类型、演进及中国实践

太平洋学报 2023年第2期31卷 68-80页

作者：李贞霏彭德雷上海市第一中级人民法院上海200336 华东理工大学法学院上海200240

数字贸易例外规则是数字贸易领域中寻求贸易自由与国家规制动态平衡的集中体现,大多散见于各双边、区域贸易协定及数字经济协定。这些数字贸易例外规则普遍参考了世界贸易组织协定中例外规则的设置模式、规范表达与功能定位,但在类型和... 详细信息

数字贸易例外规则是数字贸易领域中寻求贸易自由与国家规制动态平衡的集中体现,大多散见于各双边、区域贸易协定及数字经济协定。这些数字贸易例外规则普遍参考了世界贸易组织协定中例外规则的设置模式、规范表达与功能定位,但在类型和规范内容上存在较大差异。其中,区域贸易协定规定的数字贸易例外规则适用情形及认定,存在扩张趋向。目前中国已缔结条约的数字贸易例外规则,与《全面进步的跨太平洋伙伴关系协定》《数字经济伙伴关系协定》等国际新规则中的同类条款相比存在差距。中国应妥善应对区域和全球性数字贸易规则谈判,更好参与世界贸易组织“电子商务工作计划”,充分利用例外规则为数字贸易发展提供的空间,推进数字领域制度型开放创新,推动数字经济的整体发展。

关键词：数字贸易例外规则贸易自由规制主权

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神禾原战国秦陵墓出土涂色算筹初识

考古与文物 2023年第3期 75-80页

作者：郭妍利李振飞陕西师范大学历史文化学院西北大学文化遗产学院

神禾原战国秦陵墓出土的象牙算筹,根据筹身施彩的差别可分为红白筹和红黑筹两个主要类别,其与《九章算术》刘徽注释中提到的古代用于正负数运算的“赤黑算”似有关,应是此类计算工具的早期形态。这个发现将中国古代对正负数的认识与实... 详细信息

神禾原战国秦陵墓出土的象牙算筹,根据筹身施彩的差别可分为红白筹和红黑筹两个主要类别,其与《九章算术》刘徽注释中提到的古代用于正负数运算的“赤黑算”似有关,应是此类计算工具的早期形态。这个发现将中国古代对正负数的认识与实际运用时间提早到了战国晚期,是数学发展史研究的一大收获。

关键词：神禾原秦陵算筹正负术赤黑筹负数

离心重选-浮选脱硫工艺回收细粒级钨锡矿物的试验研究

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黄金科学技术 2022年第1期30卷 113-121页

作者：张婷李平冯博李振飞赣州有色冶金研究所有限公司江西赣州341000 江西理工大学江西赣州341000

为有效回收广西某细泥中的钨锡矿物,开展了离心重选—浮选脱硫工艺试验研究。细泥中WO_(3)、Sn含量分别为0.52%和0.31%,其中钨主要为黑钨矿和白钨矿,分别占47.69%和39.42%;锡主要以锡石形式存在,占比为75.48%,其次为硫化物中的锡,占比为... 详细信息

为有效回收广西某细泥中的钨锡矿物,开展了离心重选—浮选脱硫工艺试验研究。细泥中WO_(3)、Sn含量分别为0.52%和0.31%,其中钨主要为黑钨矿和白钨矿,分别占47.69%和39.42%;锡主要以锡石形式存在,占比为75.48%,其次为硫化物中的锡,占比为17.42%。细泥中-0.03 mm粒级产率为61.36%,其WO_(3)、Sn金属量分布率分别高达78.52%和70.39%,因此强化细粒级钨锡矿物的回收是提高选矿技术经济指标的关键。相比传统的摇床重选工艺,离心重选工艺可以有效提高细粒级钨锡矿物的选别指标,获得更高品位的粗精矿,且WO_(3)、Sn回收率分别提高了34.83%和37.43%。本研究最终采用离心重选—浮选脱硫的联合工艺进行了全流程开路试验,获得了WO_(3)、Sn品位分别为19.46%、9.87%,回收率分别为67.92%、57.52%的钨锡精矿,实现了细粒级钨锡矿物的有效回收。

关键词：细粒级钨锡矿物细泥摇床重选工艺离心重选—浮选脱硫工艺