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Non-existence of Shimura curves of Mumford type generically in the non-hyperelliptic locus

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Science China Mathematics 2025年

作者： Xin Lü Shengli Tan kang Zuo School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education) Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal University School of Mathematics and Statistics Wuhan University Institut für Mathematik Universit?t Mainz

We show that there does not exist any Shimura curve with a strictly maximal Higgs field generically in the Torelli locus of non-hyperelliptic curves of genus g≥4. In particular, Shimura curves of Mumford type are not...

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Effect of rolling temperature on microstructure and texture of twin roll cast ZK60 magnesium alloy

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Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2086-2091页

作者：陈洪美于化顺 suk-bong kang 闵光辉金云学 Provincial Key Lab of Advanced Welding Technology Jiangsu University of Science and Technology Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education Shandong University Korea Institute of Materials Science

Twin roll cast ZK60 alloy strip/sheet with final thickness of 0.5 mm was prepared, and effect of rolling temperature on microstructure and texture development was investigated using OM and XRD technique, microstructure and texture were measured on specimens subjected to rolling experiment at different rolling temperature, and macrotexture was also evaluated by X-ray diffraction method. In addition, the （1010）and （0002） pole figures were measured, and the tensile test was performed to reveal the influence of rolling temperature on mechanical properties. The results show that the microstrucmre of ZK60 alloy sheet consisted of fibrous structure with elongated grains, and shear bands along the rolling direction after warm rolling. Dynamic recrystallization could be found during the warm rolling process at rolling temperature 350℃ and above. And many fine recrystallized grain could be observed in the shear bands area. It is a little difficult to see the recrystallized grain in the sheet warm rolled at 300℃ because of higher density of shear bands. The warm rolled ZK60 alloy sheet exhibited strong （0002） pole texture, the intensity of （0002） pole figure decreases with the increasing of rolling temperature and the basal pole tilted slightly to the transverse direction after warm rolling.

关键词： warm rolling microstructure macrotexture pole figure ZK60 alloy

Dry Sliding Friction and Wear Properties and Wear Mechanism of SiC_P/Al Composites

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Journal of Wuhan University of Technology(Materials Science) 2009年第S1期24卷 24-28页

作者：金云学 Provincial Key Llaboratory of Advanced Welding Technology Jiangsu University of Science & Technology

Dry sliding friction and wear properties of A356/SiC composites against AISI D2 were analyzed by means of SEM,XRD and *** indicated that the wear rate of A356/SiC increased with increase of the applied *** wear took place under lower load,transferring to severe wear at the load heavier than 400 *** mixed layer(MML) formed on worn surface during dry sliding friction process,whose thickness became deeper with increasing *** formed easily in MML and spread transversely,resulting in peeling *** wear mechanism of the composite is that oxidation wear mechanism was dominant under low load,with the formation of tiny powdery *** the load enhanced,peeling wear was primary due to laminar debris detached from the MML,including oxidation and adhesive wear at the same time,with the load at 350-450 N,adhesive wear with irregular debris and peeling wear were predominant.

关键词： A356/SiC dry friction wear mechanism wear property

T6态A356/SiC与Semi-Metallic Pad的干滑动摩擦磨损特性

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稀有金属材料与工程 2008年第12期37卷 2147-2151页

作者：金云学 Jung-Moo Lee suk-bong kang 江苏科技大学先进焊接技术省级重点实验室江苏镇江212003 Korea Institute of Machinery and Materials Changwon 641-010Korea

选用A356/SiC复合材料与Semi-metallic pad材料进行干滑动摩擦磨损试验,并采用SEM、XRD、EDS等手段分析了复合材料的摩擦磨损特点及磨损机制。铝基复合材料与该pad间表现出非常出色的耐摩擦磨损特性,在1m/s的低滑动速度下,即使载荷增加... 详细信息

选用A356/SiC复合材料与Semi-metallic pad材料进行干滑动摩擦磨损试验,并采用SEM、XRD、EDS等手段分析了复合材料的摩擦磨损特点及磨损机制。铝基复合材料与该pad间表现出非常出色的耐摩擦磨损特性,在1m/s的低滑动速度下,即使载荷增加到700N也几乎不发生磨损;载荷不大于500N时,磨损率与滑动速度无关,保持非常小的范围。只有在高载荷、高滑动速度下才会有较为明显的磨损。摩擦系数则随载荷增大产生无规则变化,而随滑动速度的增加而减少,但变化幅度在0.1之内。复合材料耐磨特性好的主要原因是,磨损过程中磨损面上迅速形成以氧化物和石墨为主的润滑膜,减少磨损。高载荷、高滑动速度下磨损的主要特点为,复合材料表层形成塑性流动层,大的塑性流动变形使得较软的铝合金基体沿磨损方向以片状形式挤出,形成特殊的磨屑。而不易变形的SiC颗粒则留在磨损面上形成SiC聚集区,该区域又能在一定程度上减少进一步的磨损。

关键词： SiC 铝合金滑动磨损机制摩擦磨损

A356/SiC_P与列车实用中的有机闸片的滑动摩擦磨损特性

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稀有金属材料与工程 2008年第11期37卷 1956-1960页

作者：金云学 Jung-Moo Lee suk-bong kang 江苏科技大学先进焊接技术省级重点实验室江苏镇江212003 Advanced Materials Division Korea Institute of Machinery and Materials

以铝基复合材料作为列车制动盘材料的实用化为目的，选用A356／SIC 20％（体积分数，下同）复合材料和AISI D2工具钢为摩擦材料，以中速列车实用中的有机闸片为对偶材料，进行对比干摩擦磨损试验，并分析比较了磨损特性。结果表明：铝... 详细信息

以铝基复合材料作为列车制动盘材料的实用化为目的，选用A356／SIC 20％（体积分数，下同）复合材料和AISI D2工具钢为摩擦材料，以中速列车实用中的有机闸片为对偶材料，进行对比干摩擦磨损试验，并分析比较了磨损特性。结果表明：铝基复合材料在小于200Y（3．98MPa）的低载荷下，只存在轻微的氧化磨损，耐磨性比实用中的铁合金材料更好；而超过该载荷时。开始发生磨削磨损，磨损量逐步超过铁合金材料，当载荷达到400N（7．96MPa）时，由于严重的磨削磨损，磨损量剧增。而铁合金材料则随载荷和滑动速度增加，磨损率缓慢增加；磨损过程中的复合材料的摩擦系数平均值与载荷、滑动速度无关，始终保持0．3～0．4，同时随磨损距离的波动也非常小，而工具钢的摩擦系数平均值则对试验参数的敏感度相对大些，且摩擦系数平均值也比复合材料略小，即摩擦系数方面复合材料具有更好的特性。

关键词：列车制动盘铝基复合材料摩擦磨损

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang Wei kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （<0.7 V） and excellent cyclic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

SiC_p/Cu包覆粉体及其热沉材料的制备

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特种铸造及有色合金 2006年第10期26卷 620-622页

作者：王常春 suk-bong kang 闵光辉山东大学 Korea Institute of Machinery and Materials

采用化学镀铜工艺制备了Cu包覆SiCp复合粉体,并对复合粉体的组成和形貌进行了分析。同时,利用制得的复合粉体,结合适当的热压烧结工艺制备了Cu-35SiCp热沉材料,并对热沉材料的微观组织和热物理性能进行了研究。结果表明,SiCp颗粒在热沉... 详细信息

采用化学镀铜工艺制备了Cu包覆SiCp复合粉体,并对复合粉体的组成和形貌进行了分析。同时,利用制得的复合粉体,结合适当的热压烧结工艺制备了Cu-35SiCp热沉材料,并对热沉材料的微观组织和热物理性能进行了研究。结果表明,SiCp颗粒在热沉材料的基体中均匀分布,界面结合良好。在试验条件下,Cu-35SiCp热沉材料的导热系数为165.7W/(m.K),30～200℃温度区间内的热膨胀系数为15.1×10-6/K。

关键词：热沉材料化学镀导热系数热膨胀系数

铸态铝基复合材料与半金属衬片摩擦副的干滑动摩擦磨损特性研究

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摩擦学学报 2008年第3期28卷 266-271页

作者：金云学 Jung-Moo Lee suk-bong kang 江苏科技大学先进焊接技术省级重点实验室江苏镇江212003 Advanced Materials Division Korea Institute of Machinery and Materials Changwon 641-010 Korea

采用铸态A356/SiC复合材料与高速列车制动盘偶件半金属衬片材料摩擦副进行干摩擦磨损试验,并用扫描电子显微镜、X射线衍射仪和能谱仪等手段分析了复合材料的磨损机制.结果表明:复合材料表现出良好的磨损特性,在滑动速度3.0m/s以下,载荷... 详细信息

采用铸态A356/SiC复合材料与高速列车制动盘偶件半金属衬片材料摩擦副进行干摩擦磨损试验,并用扫描电子显微镜、X射线衍射仪和能谱仪等手段分析了复合材料的磨损机制.结果表明:复合材料表现出良好的磨损特性,在滑动速度3.0m/s以下,载荷达到600N(12MPa)时的磨损量仍很小;复合材料的磨损率随pv(压力与速度的积)值的增加而增大,摩擦系数则随pv值增加而小幅度减少;磨损过程中磨损表面很快形成以氧化物和以石墨为主的润滑膜,起到了减摩和耐磨作用.在pv值较低时复合材料的磨损机制为轻微的氧化磨损机制,随着pv值增加出现剥层磨损,在复合材料与半金属衬片间的接触表面,由于塑性流动挤出片状磨屑而使磨损量降低.

关键词：复合材料半金属衬片干摩擦摩擦磨损性能

Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑Life Lithium Metal Batteries

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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li Wen‑Xia Su Jia‑Min Hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑Peng Cai kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of Hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery