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Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： xin Du Pei-Han Sun Ben-Chao Gong Jian-Feng Zhang Zhong-Yi Lu Kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

An Innovative Coupled Common-Node Discrete Element Method-Smoothed Particle Hydrodynamics Model Developed with LS-DYNA and Its Applications

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China Ocean Engineering 2024年第3期38卷 467-482页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue LUO Jia-xin LIU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEM-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA *** DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure *** simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are *** interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also *** results are compared with available data to verify the proposed coupling ***,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEM-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics

CO_(2) corrosion of X80 steel welded joints under micro-turbulence induced by welding reinforcement height

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Journal of Iron and Steel Research(International) 2024年第4期31卷 1015-1032页

作者： Xiao-hui Dou Bin Li Zong-hao He xin-wei Zhang Da-lei Zhang Yan Li School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during *** welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion *** influence of WRH sizes on local corrosion of welded joints was studied at different flow *** electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam *** addition,the corrosion products composition and properties were *** results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded *** corrosion products on the WRH surface also present different microscopic morphologies at different flow *** strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded *** scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.

关键词： X80 steel welded joint Welding reinforcement height Micro-turbulence CO_(2)corrosion-Ion mass transfer

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高模量碳纤维表面双金属MOFs结构的构筑

中国有色金属学报 2024年第5期34卷 1636-1651页

作者：李淑君钱鑫张永刚朱雪张振江吴昊男蔡晨阳朱小龙宁波大学材料科学与化学工程学院宁波315211 中国科学院宁波材料技术与工程研究所碳纤维制备技术国家工程实验室宁波315201 宁波市计量测试研究院宁波新材料检验检测中心国家磁性材料产业计量测试中心宁波315048

经高温热处理制备得到的碳纤维具有高惰性表面结构,导致其与基体之间的润湿性较差。为了改善碳纤维与基体间的界面性能,本研究通过采用阴极电沉积法在高模量碳纤维表面原位生长金属有机框架(MOFs)材料,在纤维表面同时引入两种不同金属元... 详细信息

经高温热处理制备得到的碳纤维具有高惰性表面结构,导致其与基体之间的润湿性较差。为了改善碳纤维与基体间的界面性能,本研究通过采用阴极电沉积法在高模量碳纤维表面原位生长金属有机框架(MOFs)材料,在纤维表面同时引入两种不同金属元素,研究双金属MOFs的引入机制、形貌及其对性能的影响。结果表明:双金属MOFs材料呈一定取向的绣球状形貌,经退火后演变成疏松多孔结构,该结构可显著提高高模量碳纤维表面粗糙度及界面黏结性;双金属MOFs的成核与生长取决于金属还原性,还原性越强、MOF生长速率更快,且沉积量更高;双金属MOFs结构的引入使得纤维电阻率下降至0.05×10^(−5)Ω∙cm,导电性能提升,独特的三维多孔结构也赋予高模量碳纤维高温环境下优异的热稳定性。

关键词：碳纤维金属有机框架金属离子导电性表面粗糙镀

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北京市丰台区疫情期间集中隔离场所医学观察人员及医务人员特征分析

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国际病毒学杂志 2023年第5期30卷 413-415页

作者：黄儒婷信振江张建军谢俊卿北京市丰台区疾病预防控制中心环境卫生科 100071

目的了解新型冠状病毒感染(COVID-19)疫情期间,北京市丰台区集中隔离场所的医学观察人员及驻点医务人员的相关特征,为局部疫情快速应急处置提供科学依据。方法收集2021年10月18日至11月26日期间丰台区集中隔离观察点、医学观察人员、隔... 详细信息

目的了解新型冠状病毒感染(COVID-19)疫情期间,北京市丰台区集中隔离场所的医学观察人员及驻点医务人员的相关特征,为局部疫情快速应急处置提供科学依据。方法收集2021年10月18日至11月26日期间丰台区集中隔离观察点、医学观察人员、隔离点医护人员信息,使用SPSS 19.0进行统计分析。结果疫情期间,北京市丰台区共启用10个集中隔离观察点,共计2434人纳入集中医学观察,以次密接人员管控(53.2%)最多。隔离点平均使用天数为(31.30±6.73)d,155名医务人员参与了集中隔离工作。医务人员主要来自于社区卫生服务中心(65.8%),专业背景以护理专业(48.4%)和临床专业(41.3%)为主,进点前有隔离点工作经验的人员占23.9%。每百名管控人员配备的医务人员平均为(6.23±2.98)人,高于国家100∶4要求(t=4.74,P<0.01)。后续病例均在医学观察期间检出,未发生隔离点内交叉感染。结论集中隔离观察点是精准防控疫情的重要环节,要及时总结集中隔离点的实战经验。基层医护人员是开展隔离点工作的主力军,老带新、培训演练、应急预案等是妥善处置隔离点突发事件的有效应对方式,公共卫生专业人员"一对一"包点指导可以有效弥补专业人员不足。

关键词：新型冠状病毒感染集中隔离观察场所集中隔离局部疫情

In situ meso-tetra(4-carboxyphenyl)porphyrin ligand substitution in Hf-MOF for enhanced catalytic activity and stability in photoredox reactions

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Rare Metals 2024年第6期43卷 2682-2694页

作者： Jie Hu Hong-xin Lao Xiu-Wu Xu Wei-Kang Wang Le-Le Wang Qin-Qin Liu School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China College of Chemistry and Materials Engineering Research Center of Carbon NeutralityAnhui Normal UniversityWuhu 241002China Fujian Provincial Key Laboratory of Ecology-Toxicological Effects and Control for Emerging Contaminants Putian UniversityPutian 351100China

Though there are numerous intrinsic merits of metal-organic frameworks(MOFs),low charge separation efficiency has imposed heavy restrictions on their photocatalytic ***,in situ porphyrin ligand substitution,as a strategy for improving the charge separation efficiency and increasing the amounts of active sites,has been designed and realized in a Hf-biphenyl dicarboxylic acid(BPDC)***,a size and geometry matched meso-tetra(4-carboxyphenyl)porphyrin(TCPP)ligand was selected and doped into Hf-BPDC MOF by forming coordinating bonds with Hf centers,forming dualligand Hf-BPDC-TCPP *** resultant Hf-BPDC-TCPP MOF showed significantly improved activity and chemical stability in the photocatalytic H_(2)generation(261μmol·g^(-1)·h^(-1))and tetracycline(TC)degradation reactions(95.8%),which was 48 and 1.47 folds higher than that of the Hf-BPDC *** and electrochemical studies revealed that the introduction of porphyrin ligand could generate a stronger internal electric field for boosting the charge separation and transfer,increase the specific surface area for providing more active sites,and narrow the band gap to enhance the visible light *** in situ ligand substitution method provides a promising approach to build a tunable platform for constructing high-performance MOF photocatalysts.

关键词： Ligand substitution Metal organic frameworks Meso-tetra(4-carboxyphenyl)porphyrin Hydrogen evolution reaction Tetracycline degradation

2011-2021年北京市丰台区肺结核流行特征分析

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中华预防医学杂志 2022年第9期56卷 1302-1306页

作者：胡远莲艾萍贾雪娇张东彦薛晓邓玲陈巍杨国梁常利杰信振江北京市丰台区疾病预防控制中心结核病防制科北京100071 北京市丰台区疾病预防控制中心办公室北京100071

目的分析2011-2021年北京市丰台区肺结核流行特征。方法采用回顾性研究方法, 通过中国疾病预防控制信息系统收集2011年1月1日至2021年12月31日的丰台区肺结核病例资料, 包括病原学分类、性别、年龄、职业、发病时间, 人口信息等, 对肺... 详细信息

目的分析2011-2021年北京市丰台区肺结核流行特征。方法采用回顾性研究方法, 通过中国疾病预防控制信息系统收集2011年1月1日至2021年12月31日的丰台区肺结核病例资料, 包括病原学分类、性别、年龄、职业、发病时间, 人口信息等, 对肺结核病例的流行病学特征进行描述性分析。结果 2011-2021年丰台区报告肺结核患者共计10 342例, 年平均发病率为 42.87/10万, 2012年发病率最高(75.89/10万), 2013年开始逐年大幅度下降, 到2017年降至29.70/10万, 2018-2021年有缓慢上升趋势(χ^(2)=1 471.77, P<0.001)。2011-2021年肺结核病原学阳性病例2 975例, 2017-2021年利福平耐药病例76例;男、女性别比为1.75, 男性年平均发病率(53.94/10万)高于女性(31.57/10万)(χ^(2)=704.01, P<0.001);25~29、20~24、30~34岁年龄组的构成比较高, 分别为14.56%(1 506例)、12.49%(1 292例)、9.90%(1 024例);<10岁组年平均发病率最低(1.43/10万), ≥85岁组发病率较高(195.20/10万), 差异有统计学意义(χ^(2)=3 164.24, P<0.001)。构成比较高的职业有家务及待业(2 917例, 28.21%)、离退人员(2 308例, 22.32%)、工人(1 047例, 10.12%)、干部职员(950例, 9.19%)、农民(860例, 8.32%)、商业服务(698例, 6.75%)、教师和学生(455例, 4.40%)。结论 2011-2021年丰台区肺结核发病率从2012-2017年下降后, 随后有缓慢上升趋势;肺结核发病存在年龄和性别差异。

关键词：结核肺发病率监测

Ribosome-inspired electrocatalysts inducing preferential nucleation and growth of three-dimensional lithium sulfide for high-performance lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第7期94卷 517-526页

作者： Zhen Wu Wenfeng He Jiahui Yang Yunuo Gu Ruiqi Yang Yiran Sun Jiajia Yuan xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina FEB Res Inst Far East BatteryWuxi 214200JiangsuChina

Nucleation of lithium sulfide(Li_(2)S)induced by electrocatalysts plays a crucial role in mitigating the shut-tle ***,short-chain polysulfides on electrocatalysts surfaces tend to re-dissolve into elec-trolytes,delaying Li_(2)S supersaturation and its *** this study,we draw inspiration from the ribosome-driven protein synthesis process in cells to prepare ultrasmall nitrogen-doped MoS_(2) nanocrys-tals anchored on porous nitrogen-doped carbon networks(N-MoS_(2)-NC)***,the ex-situ SEM demonstrates that ribosome-inspired N-MoS_(2)-NC electrocatalysts induce early nucleation and rapid growth of three-dimensional Li_(2)s during *** calculations reveal that the Li-s bond length in N-MoS_(2)-Li_(2)S(100)is shorter,and the corresponding interfacial formation energy is lower than in MoS_(2)-Li_(2)S(100).This accelerated conversion of lithium polysulfides to Li_(2)S can enhance the utilization of active substances and inhibit the shuttle *** study highlights the potential of ribosome-inspired N-MoS_(2)-NC in improving the electrochemical stability of Li-S batteries,providing valuable insights for future electrocatalyst design.

关键词： Lithium-sulfur batteries Electrocatalysts Nanocrystals Ribosome-inspired Nucleation and growth

Effect of solidification mode on microstructure evolution and properties of magnesium alloy with long-period stacking ordered phase

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1127-1138页

作者： Hao Li Hong-mei Chen Xu Zhang Qian-hao Zang Jing Zhang Di Feng Yan-xin Qiao Yu-hang Guo School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100JiangsuChina School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologySuzhou215600JiangsuChina

The solidification methods of electromagnetic stirring(EMS)and non-electromagnetic stirring were employed to prepare Mg–6Gd–3Y–xZn–0.6Zr(x=1,1.5,2,3)*** evolution of alloy microstructures and the changes in properties were analyzed for different Zn *** has been observed that in alloys without electromagnetic stirring,as the Zn content increases,the alloy structure gradually *** primary second phase transitions from Mg5RE phase to long-period stacking ordered(LPSO)phase,resulting in improved hardness and *** alloys subjected to electromagnetic stirring,there is a relatively higher content of the second phase,primarily consisting of LPSO *** applying electromagnetic stirring,the quantity and the type of LPSO phase in the alloy *** alloy structure becomes more uniform with electromagnetic stirring,resulting in increased hardness and reduced hardness gradients within the *** mechanical properties of alloys with electromagnetic stirring are superior to those without electromagnetic stirring.

关键词： Rare earth magnesium alloy LPSO phase Electromagnetic stirring Casting Property