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Nano Research 2024年第3期17卷 1225-1231页

作者： zichun Wang Dan Wang ang Li Lizhuo Wang Xiaodong Han Yijiao Jiang Jianfeng Chen Jun Huang Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic–Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029China Laboratory for Catalysis Engineering School of Chemical and Biomolecular EngineeringThe University of SydneyNew South Wales 2006Australia Beijing Key Laboratory of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100024China Department of Engineering Macquarie UniversitySydneyNew South Wales 2109Australia

Metal nanowires show promise in a broad range of applications and can be fabricated via a number of methods,such as vapor–liquid–solid process and template-based ***,the synthesis of Al nanowires(NWs)is still challenging from the stable alumina *** this work,the Ni-catalyzed fabrication of Al NWs has been realized using various Al_(2)O_(3) *** growth dynamics of Al NWs on Ni/Al_(2)O_(3) was studied using in situ transmission electron microscopy(TEM).The effect of alumina structures,compositions,and growth temperature were *** growth of Al NWs correlates with the Na addition to the alumina *** no eutectic mixture of nickel aluminide was formed,a mechanism of Ni-catalyzed reduction of Al_(2)O_(3) for Al NWs growth has been proposed instead of the vapor–liquid–solid *** key insights reported here are not restricted to Ni-catalyzed Al NWs growth but can be extended to understanding the dynamic change and catalytic performance of Ni/Al_(2)O_(3) under working conditions.

关键词： in situ transmission electron microscopy(TEM) Al nanowires alumina reduction nanowire growth

X-ray excited Mn^(2+)-doped persistent luminescence materials with biological window emission for in vivo bioimaging

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Journal of Rare Earths 2024年第1期42卷 28-35,I0001页

作者： Hanrun zheng Lin Liu Yi’ang Li Rui Rong Liang Song Junpeng Shi Jing Teng Xia Sun Yun z.ang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China University of the Chinese Academy of Sciences Beijing100049China Xiamen Hospital of Traditional Chinese Medicine Xiamen361015China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China

In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity *** metal Mn^(2+)is an ideal emission center,but few studies focus on Mn^(2+)-doped PLMs with X-ray excitation and biological window ***,we report a Mn^(2+)-doped PLM,LiYGeO_(4):Mn^(2+)(LYGM),with excellent biological window persistent luminescence *** excitation by UV,LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 *** *** can be repeatedly excited by X-rays,resulting in long-term biological window persistent luminescence *** addition,we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in *** LYGM are injected into mice through the tail vein,in situ excitation of X-rays can be *** the persistent luminescence decays,LYGM can be re-excited for repeated ***,LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging.

关键词： Persistent luminescence X-ray Biological window In vivo imaging Rare earths

Effects of longitudinal magnetic field on primary dendrite spacing and segregation of directionally solidified single crystal superalloy

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Progress in Natural Science:Materials International 2024年第1期34卷 26-36页

作者： Congjiang z.ang Yilin zhou Chen Shen Weili Ren Xiaotan Yuan Biao Ding Haibiao Lu zuosheng Lei Yunbo zhong ang z.ang State Key Laboratory of Advanced Special Steel College of Materials Science and Engineering Shanghai University National Engineering Research Center for Magnesium Alloys Natural Key Laboratory of Advanced Casting Technologies College of Materials Science and EngineeringChongqing University

The primary dendrite spacing(PDS) and segregation of directionally solidified single crystal(SC) superalloy under the longitudinal magnetic field(LMF) were investigated based on the analysis of the whole cross-sectional microstructure at different solidification distances. The results show that the PDS under the LMF remains basically unchanged at different solidification distances, and it is greater than that under no LMF. With the increase of magnetic field intensity, the PDS increases and the macrosegregation decreases. The increasing PDS and reducing segregation under the LMF can be attributed to the increase of solute boundary layer, which expands the non-equilibrium freezing temperature range and brings the effective partition coefficient closer to 1. The increase of the solute enrichment layer thickness could be caused by the downward secondary circulation generated by the thermoelectric magnetic convection(TEMC) near the interface, which drives the migration of solutes towards the interdendritic region. This work not only clarifies the mechanism of LMF controlling PDS and reducing segregation by TEMC, but also provides theoretical guidance for producing high-quality SC superalloys using magnetic fields.

关键词： Primary dendrite spacing Segregation Single crystal superalloy Directional solidification Magnetic field Thermoelectric magnetic convection

Reconcile the contradictory wettability requirements for the reduction and oxidation half-reactions in overall CO_(2) photoreduction via alternately hydrophobic surfaces

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Journal of Energy Chemistry 2024年第6期93卷 202-212,I0006页

作者： Hailing Huo Ting Hu Chengxi Huang Fang Wu Tongyu Wang Xuan Liu Liang z.ang Qiang Ju zhiqing zhong Hongbin Xing Erjun Kan ang Li MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing Nanjing University of Science and TechnologyNanjing 210094JiangsuChina College of Information Science and Technology Nanjing Forestry UniversityNanjing 210037JiangsuChina

The overall photocatalytic CO_(2) reduction reaction(OPCRR)that can directly convert CO_(2) and H_(2)O into fuels represents a promising renewable energy conversion *** a typical redox reaction,the OPCRR involves two half-reactions:the CO_(2) reduction half-reaction(CRHR)and the water oxidation half-reaction(WOHR).Generally,both half-reactions can be promoted by adjusting the wettability of ***,there is a contradiction in wettability requirements for the two ***,CRHR prefers a hydrophobic surface that can accumulate more CO_(2) molecules on the active sites,ensuring the appropriate ratio of gas-phase(CO_(2))to liquid-phase(H_(2)O)***,the WOHR prefers a hydrophilic surface that can promote the departure of the gaseous product(O_(2))from the catalyst surface,preventing isolation between active sites and the reactant(H_(2)O).Here,we successfully reconciled the contradictory wettability requirements for the CRHR and WOHR by creating an alternately hydrophobic *** was achieved through a selectively hydrophobic modification method and a charge-transfer-control ***,the collaboratively promoted CRHR and WOHR led to a significantly enhanced OPCRR with a solar-to-fuel conversion efficiency of 0.186%.Notably,in ethanol production,the catalyst exhibited a 10.64-fold increase in generation rate(271.44μmol g^(-1)h~(-1))and a 4-fold increase in selectivity(55.77%)compared to the benchmark *** innovative approach holds great potential for application in universal overall reactions involving gas participation.

关键词： Hydrophobic Hydrophilic Gas transport Overall CO_(2)photoreduction z-scheme

Cationic ordering transition in oxygen-redox layered oxide cathodes

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Carbon Energy 2024年第1期6卷 197-206页

作者： Xinyan Li ang Gao Qinghua z.ang Hao Yu Pengxiang Ji Dongdong Xiao Xuefeng Wang Dong Su Xiaohui Rong Xiqian Yu Hong Li Yong-Sheng Hu Lin Gu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijingChina College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijingChina Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials School of Materials Science and EngineeringTsinghua UniversityBeijingChina Beijing Advanced Innovation Center for Materials Genome Engineering Huairou DivisionInstitute of PhysicsChinese Academy of SciencesBeijingChina

Understanding the structural origin of the competition between oxygen 2p and transition-metal 3d orbitals in oxygen-redox(OR)layered oxides is eminently desirable for exploring reversible and high-energy-density Li/Na-ion ***,we reveal the correlation between cationic ordering transition and OR degradation in ribbon-ordered P3-Na_(0.6)Li_(0.2)Mn_(0.8)O_(2) via in situ structural *** two different voltage windows,the OR capacity can be improved approximately twofold when suppressing the in-plane cationic ordering *** find that the intralayer cationic migration is promoted by electrochemical reduction from Mn^(4+)to Jahn–Teller Mn^(3+)and the concomitant NaO_(6) stacking transformation from triangular prisms to octahedra,resulting in the loss of ribbon ordering and electrochemical ***-principles calculations reveal that Mn^(4+)/Mn^(3+)charge ordering and alignment of the degenerate eg orbital induce lattice-level collective Jahn–Teller distortion,which favors intralayer Mn-ion migration and thereby accelerates OR *** findings unravel the relationship between in-plane cationic ordering and OR reversibility and highlight the importance of superstructure protection for the rational design of reversible OR-active layered oxide cathodes.

关键词： cationic ordering layered oxide cathodes oxygen redox sodium-ion batteries

Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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National Science Review 2024年第4期11卷 172-184页

作者： zibing An Tao Yang Caijuan Shi Shengcheng Mao Lihua Wang ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu ze z.ang Xiaodong Han Beijing Key Lab of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology Department of Materials Science and Engineering City University of Hong Kong Key Laboratory of Partial Acceleration Physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences Department of Materials Science &Engineering Southern University of Science and Technology Department of Physics City University of Hong Kong State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

创造性执行的定位与调适策略研究——基于z省Q市环境医院项目执行过程的个案分析

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中国行政管理 2024年第5期40卷 28-36页

作者：徐强吴昂中国人民大学生态环境学院北京100872 中国人民大学法学院北京100872

创造性执行是新一届政府提出的施政要求。就其本质而言,创造性执行可被视为政策执行活动的一种细分类型,创造性执行的核心要义是服务高质量发展导向下执行方式的灵活创新,以服务发展目标补充、强化、平衡、修正原政策的形式目标与实质精... 详细信息

创造性执行是新一届政府提出的施政要求。就其本质而言,创造性执行可被视为政策执行活动的一种细分类型,创造性执行的核心要义是服务高质量发展导向下执行方式的灵活创新,以服务发展目标补充、强化、平衡、修正原政策的形式目标与实质精神,追求政策执行效果的整体提升。在创造性执行中,执行主体需注意与目标群体的调适,通过多种调适策略增进目标群体的理解和接受程度。本文基于对z省Q市环境医院项目执行过程的分析,呈现了创造性执行中执行主体与目标群体的调适过程,其中既包含了与企业平等对话交流和主动服务的对话型策略,也有通过严格监管激发企业需求、借势中央生态环保督察的压力型策略。由此可知,采取多样调适策略增进目标群体的理解和接受,对推动创造性执行具有重要意义。

关键词：创造性执行政策执行互适模型调适策略

从zygmund型空间到Bloch型空间的复合算子的差分

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天津师范大学学报（自然科学版） 2024年第3期44卷 1-6,44页

作者：刘金昊梁玉霞周航天津师范大学数学科学学院天津300387 广州商学院信息技术与工程学院广州511363

给出复合算子的差分C_(φ)-C_(ψ):z_(α)→B^(β)(α>1,β>0)的有界性与紧性的一些等价条件.此外,作为非平凡的拓展,利用Taylor级数和Raabe判别法构建了有界或紧的复合算子的差分C_(φ)-C_(ψ):z_(α),0→B^_(0)(β)的等价刻画.

关键词：差分复合算子 zygmund型空间 Bloch型空间

A fringe jump counting method for the phase measurement in the HCN laser interferometer on EAST and its FPGA-based implementation

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Plasma Science and Technology 2024年第4期26卷 156-161页

作者：姚远杨曜提昂宋扬张家敏王琰张耀刘海庆揭银先 Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Anhui Electrical Engineering Professional Technique College Hefei 230022People’s Republic of China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601People’s Republic of China

Electron density in fusion plasma is usually diagnosed using laser-aided interferometers. The phase difference signal obtained after phase demodulation is wrapped, which is also called a fringe jump. A method has been developed to unwrap the phase difference signal in real time using FPGA, specifically designed to handle fringe jumps in the hydrogen cyanide(HCN) laser interferometer on the EAST superconducting tokamak. This method is designed for a phase demodulator using the fast Fourier transform(FFT) method at the front end. The method is better adapted for hardware implementation compared to complex mathematical analysis algorithms, such as field programmable gate array(FPGA). It has been applied to process the phase measurement results of the HCN laser interferometer on EAST in real time. Electron density results show good confidence in the fringe jump unwrapping method. Further possible application in other laser interferometers, such as the POlarimeter-INTerferometer(POINT)system on EAST tokamak is also discussed.

关键词： electron density laser-aided interferometer fringe jump unwrapping FPGA EAST

双层单原子催化剂用于促进高活性和选择性电催化硝酸盐还原制氨

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物理化学学报 2024年第6期40卷 60-62页

作者：于镜坤雍雪曹昂卢思宇郑州大学化学学院绿色催化中心郑州450001 Department of Chemistry University of SheffieldSheffieldS37HFUK Department of Physics Technical University of DenmarkKongens Lyngby 2800Denmar

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSA... 详细信息

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSACs)进行了系统研究,通过轴向d-d轨道杂化提高了从SACs到BSACs的电催化硝酸盐还原反应(NO_(3)RR)的活性和选择性。考虑到可能的O端、N端、NO端和NO二聚体途径,计算结果显示,在单层SACs中,Ti-Pc和V-Pc分别具有优异的极限电位(U_(L)),分别为-0.24和-0.48V。形成能、溶解势以及从头算分子动力学结果表明,在反应条件下,这些催化剂非常稳定。在这些单层TM-Pc中,它们的d带能级和占据数受到d_(xz)/d^(yz)和p_(z)轨道杂化的影响。其轴向d_(z^(2))轨道的可用性通过形成d_(z^(2))-d_(z^(2))相互作用来进一步调整d带和反应性。在此基础上,以Ti-Pc和V-Pc为底物,通过形成轴向d-d轨道杂化来构建BSACs,为调节NO_(3)RR催化性能提供了一种独特的新途径。重要的是,我们发现d带中心(εd)、d_(xz)+d_(yz)轨道的占据数和U_(L)之间存在二维火山关系,用于描述它们的NO_(3)RR催化性能。最佳的BSACs应该同时具备适当的ε_(d)和d_(xz)+d_(yz)占用数。Ti-Mo和Ti-Ta被确定为出色的NO_(3)RR催化剂,其U_(L)均降低至-0.13 V。而d_(z^(2))-d_(z^(2))轨道之间的杂化则增强了双层金属之间的电荷转移和结构稳定性。缺乏相邻的金属位点将导致生成NO_(2)、NO和N_(2)的能垒较高,从而抑制副产物生成。最终,本研究揭示了在SACs和BSACs上对硝酸盐还原进行合理优化的方法,可为改进电催化剂的设计提供指导。

关键词：硝酸盐还原第一性原理计算单原子催化剂双层单原子催化剂轴向轨道杂化