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An air-stable single-crystal layered oxide cathode based on multifunctional structural modulation for high-energy-density sodium-ion batteries

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Science China Chemistry 2024年

作者： Yi-Feng Liu Hai-Yan Hu Jia-Yang Li Hongrui Wang Yi Zhao Jingqiang Wang Yuan-Bo Wu Yan-Jiang Li Guang-Yu zhang Qing-Qun Sun Yan-Fang Zhu Rui-Ren Tang Xiong-Wei Wu Jia-Zhao Wang Shi-Xue Dou Shu-Lei Chou Yao Xiao Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University School of Chemistry and Materials Science Hunan Agricultural University Institute of Energy Materials Science University of Shanghai for Science and Technology Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Institute for Carbon Neutralization College of Chemistry and Materials Engineering Wenzhou University College of Chemistry and Chemical Engineering Central South University

P2-type layered oxide, Na2/3Ni1/3Mn2/3O2, has drawn particular interest as a promising cathode material for sodium-ion batteries(SIBs) due to its fast sodium-ion transport channels with low migration potential. However, some catastrophic flaws, such as air instability, complicated multiphase evolution, and irreversible anionic redox, limit its electrochemical performance and hinder its application. Here, an air-stable single-crystal P2-type Na2/3Ni1/3Mn1/3Ti1/3O2is proposed based on the multifunctional structural modulation of Ti substitution that could alleviate the issues for practical SIBs. As a result, the cathode with high energy density shows excellent air stability and highly reversible phase transitions(P2–OP4), and delivers faster kinetics and stable anion redox chemistry. Meanwhile, a thorough investigation of the relationship between structure, function, and properties is demonstrated,emphasizing formation processes, electrochemical behavior, structural evolution, and air stability. Overall, this study provides the direction of multifunctional structural modulation for the development of high-performance sodium-based layered cathode materials for practical applications.

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Metabolic and transcriptomic analyses elucidate a novel insight into the network for biosynthesis of carbohydrate and secondary metabolites in the stems of a medicinal orchid Dendrobium nobile

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Plant Diversity 2023年第3期45卷 326-336页

作者： Yu-Wen zhang Yu-Cen Shi Shi-Bao zhang Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Yunnan Key Laboratory for Wild Plant Resources Kunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China Lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang 674100YunnanChina

Dendrobium nobile is an important medicinal and nutraceutical *** the ingredients of *** have been identified as polysaccharides,alkaloids,amino acids,flavonoids and bibenzyls,our understanding of the metabolic pathways that regulate the synthesis of these compounds is ***,we used transcriptomic and metabolic analyses to elucidate the genes and metabolites involved in the biosynthesis of carbohydrate and several secondary metabolites in the stems of ***.A total of 1005 metabolites and 31,745 genes were detected in the stems of *** majority of these metabolites and genes were involved in the metabolism of carbohydrates(fructose,mannose,glucose,xylulose and starch),while some were involved in the metabolism of secondary metabolites(alkaloids,β-tyrosine,ferulic acid,4-hydroxybenzoate and chrysin).Our predicted regulatory network indicated that five genes(AROG,PYK,DXS,ACEE and HMGCR) might play vital roles in the transition from carbohydrate to alkaloid *** analysis identified that six genes(ALDO,PMM,BGLX,EGLC,XYLB and GLGA) were involved in carbohydrate metabolism,and two genes(ADT and CYP73A) were involved in secondary metabolite *** analyses also indicated that phosphoenol-pyruvate(PEP) was a crucial bridge that connected carbohydrate to alkaloid *** regulatory network between carbohydrate and secondary metabolite biosynthesis established will provide important insights into the regulation of metabolites and biological systems in Dendrobium species.

关键词： Dendrobium nobile Transcriptome Metabolome Polysaccharides Alkaloids Secondary metabolite biosynthesis

PREPARATION AND PROPERTIES OF COATED SEMICONDUCTOR CdS/ZnS NANOPARTICLES

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Chinese Chemical Letters 1995年第11期6卷 1013-1016页

作者： Qi, LM Ma, JM Cheng, HM Zhao, zg Beijing Univ Dept Chem Beijing 100871 Peoples R China

Coated semiconductor CdS/ZnS nanoparticles were fabricated by coating the CdS core with a layer of ZnS in inverse micelle solutions. The optical absorption and photoluminescence (PL) characteristics of the coated CdS/ZnS nanoparticles were investigated and provided evidence for a core-shell structure in these particles. A new PL band with a maximum at 630nm arised from the coated particles and the PL intensity increased with increasing the amount of ZnS coated on the CdS core.

关键词： ZnS PREPARATION AND PROPERTIES OF COATED SEMICONDUCTOR CdS/ZnS NANOPARTICLES CdS

Interface bond mechanisms of ceramic-cemented carbide compact insert

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Chinese Science Bulletin 1997年第14期42卷 1227-1230页

作者： Deng, JX Al, X Hou, zg Li, ZQ Department of Mechanical Engineering Shandong University of Technology Jinan China

SINCE the 1970s coated cemented carbide tools have been developed so as to further improvetheir wear and heat resistance. For the coated tools, cemented carbide with high strength andfracture toughness are selected as matrix materials, carbide, boride and nitride with highhardness are used as coating materials. Because the coating thickness of the coated tools is gen-

关键词： ceramic composite cemented carbide compact insert interface.

REACTIONS　IN　MICROEMULSION　FORMED　BY　ANIONIC－NONIONIC　MIXED　SURFACTANT，WATER　AND　HEPTANE

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Chinese Chemical Letters 1995年第1期6卷 67-70页

作者： Ma, JM Cheng, HM Zhao, zg Qi, LM Beijing Univ Dept Chem Beijing 100871 Peoples R China

ＲＥＡＣＴＩＯＮＳＩＮＭＩＣＲＯＥＭＵＬＳＩＯＮＦＯＲＭＥＤＢＹＡＮＩＯＮＩＣ－ＮＯＮＩＯＮＩＣＭＩＸＥＤＳＵＲＦＡＣＴＡＮＴ，ＷＡＴＥＲＡＮＤＨＥＰＴＡＮＥＪｉＭｉｎｇＭＡ；ＨｕＭｉｎＣＨＥＮＧ；ＺｈｅｎＧｕｏＺＨ... 详细信息

ＲＥＡＣＴＩＯＮＳＩＮＭＩＣＲＯＥＭＵＬＳＩＯＮＦＯＲＭＥＤＢＹＡＮＩＯＮＩＣ－ＮＯＮＩＯＮＩＣＭＩＸＥＤＳＵＲＦＡＣＴＡＮＴ，ＷＡＴＥＲＡＮＤＨＥＰＴＡＮＥＪｉＭｉｎｇＭＡ；ＨｕＭｉｎＣＨＥＮＧ；ＺｈｅｎＧｕｏＺＨＡＯａｎｄＬｉＭｉｎＱＩＤｅｐａｒ...

关键词： HEPT FORM

The generalized self-similarity and scaling in variance in fluid motions

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Chinese Science Bulletin 1997年第1期42卷 61-64页

作者： Liu, SD Lui, SK Jiang, MS Zheng, zg Department of Geophysics Peking Univemity Beijing China Beijing Institute of Meteorology Beijing China

ATMOSPHERIC and oceanic flows stride across very wide scale. For example, the scale of large vortexes is of the order of 10~6 m, while the scale of small vortexes is of only a few millimeters in the atmosphere. The scales of turbulent flows in the inertial range stride across three orders of magnitude in atmospheric surface layer. The monthly mean surface air temperature data in the Northern Hemisphere from 1851 to 1984 include the four different

关键词： self-similarity scaling scaling invariance.

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三峡库区白水河滑坡位移与裂缝分形特征

地质科技通报 2024年第4期43卷 244-251页

作者：谢媛华张国伟曹宗伟苗发盛中国地质大学(武汉)出版社武汉430074 中国地质大学(武汉)工程学院武汉430074 青海省柴达木综合地质矿产勘查院青海格尔木816099 西安测绘总站西安710054

地表位移与裂缝发育是滑坡变形演化最为直观的表现形式,因此,通过位移监测数据与地表裂缝发育状况来揭示滑坡变形破坏特征与演化阶段对于滑坡灾害的分析防治具有重要的现实意义。选取三峡库区白水河滑坡为研究对象,系统搜集并分析了2003... 详细信息

地表位移与裂缝发育是滑坡变形演化最为直观的表现形式,因此,通过位移监测数据与地表裂缝发育状况来揭示滑坡变形破坏特征与演化阶段对于滑坡灾害的分析防治具有重要的现实意义。选取三峡库区白水河滑坡为研究对象,系统搜集并分析了2003-2016年滑坡监测数据,选取zg93和zg118监测点,首先基于R/S分析计算了位移数据的分形参数Hurst指数;其次以每年为时间间隔对2个监测点位移进行多重分形维数计算研究;最后引入滑坡裂缝分期配套理论,对白水河滑坡目前裂缝发育状况进行裂缝分形维数计算。结果表明,2个监测点位移分形维数H指数均大于0.5,说明滑坡位移序列存在一定的正相关性;白水河滑坡演化过程分为平稳变形状态(2003年6月-2007年6月)、加速变形状态(2007年6月-2009年12月)、平稳变形状态(2009年12月-2015年12月);对比地表裂缝分形维数与滑坡裂缝分期配套规律可知,白水河滑坡目前裂缝发育仍然处在初始变形阶段。研究成果对于揭示水库滑坡的演化状态具有一定的指导意义。

关键词：分形理论白水河滑坡位移裂缝三峡库区

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统筹职业教育、高等教育、继续教育协同创新的国际经验与启示

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中国职业技术教育 2024年第6期 11-20页

作者：谢青松李雪婵张伟远重庆开放大学大数据应用研究院广东开放大学学分银行管理中心北京师范大学首都学习型社会研究院

统筹各类教育协同创新是推进教育体系现代化建设和教育治理结构性变革的重要基础。党的二十大报告明确提出“统筹职业教育、高等教育、继续教育协同创新”,从国家顶层设计层面为三类教育的融合发展指明了方向。基于国际比较研究,从本体... 详细信息

统筹各类教育协同创新是推进教育体系现代化建设和教育治理结构性变革的重要基础。党的二十大报告明确提出“统筹职业教育、高等教育、继续教育协同创新”,从国家顶层设计层面为三类教育的融合发展指明了方向。基于国际比较研究,从本体论和方法论视角发现国际上职业教育、高等教育、继续教育协同创新的模式主要包括协议代言模式、衔接贯通模式、并行双轨模式和趋同融合模式;协同创新的路径主要包括学分转换、转学教育、双部门大学和资历名册;协同创新的机制主要有法律制度、资历框架、学分银行、过往学习成果认证和质量保证。国际理论研究与实践为我国三类教育的协同创新提供了以下启示:第一,基于数字技术实施弹性学制和完全学分制,建立“三教”衔接与贯通的基础;第二,基于产教融合理念系统规划课程设置,打通“三教”协同与融合的通道;第三,基于教育强国目标推进教育治理体系现代化,建立“三教”协同创新的制度与标准;第四,基于数字技术应用,搭建“三教”协同创新的平台。

关键词： “三教”协同职业教育高等教育继续教育资历框架数字技术

Vibrational investigation of 1-cyclopentylpiperazine:A combined experimental and theoretical study

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1654-1661页

作者： BAGLAYAN zge KESAN Gürkan PARLAK Cemal ALVER zgür SENYEL Mustafa Department of Physics Science Faculty Anadolu University Institute of Physics and Biophysics Faculty of Science University of South Bohemia Department of Physics Dumlupinar University

FT-IR and Raman spectra of 1-cyclopentylpiperazine(1cppp)have been experimentally examined in the region of 4000–*** optimized geometric parameters,conformational equilibria,normal mode frequencies and corresponding vibrational assignments of 1cppp(C9H18N2)are theoretically examined by means of B3LYP hybrid density functional theory(DFT)method together with 6-31++G(d,p)basis *** the basis of potential energy distribution(PED)reliable vibrational assignments have been made and the thermodynamics functions,highest occupied and lowest unoccupied molecular orbitals(HOMO and LUMO)of 1cppp have been *** are employed for four different conformations in C1 and Cs point groups of 1cppp in gas *** between the experimental and theoretical results indicates that B3LYP method is able to provide satisfactory results for predicting vibrational frequencies and the structural parameters,vibrational frequencies and ***,C1(equatorial-axial)point group has been found as the most stable conformer of 1cppp.

关键词：振动频率环戊基实验 B3LYP方法杂化密度泛函理论构象平衡 FT-IR 热力学函数