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N-Doped porous carbon supported palladium nanoparticles as a highly efficient and recyclable catalyst for the Suzuki coupling reaction

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Chinese Chemical Letters 2016年第1期27卷 149-154页

作者： Li Zhang Wen-Huan Dong ning-zhao shang Cheng Feng Shu-Tao Gao Chun Wang College of Science Agricultural University of Hebei

A new catalyst, Pd particles supported on the N-doped porous carbon（PC） derived from Zn-based metal-organic frameworks（zeolitic imidazolate framework： ZIF-8）, was successfully prepared for the first *** as-prepared catalyst was designated as N-doped PC-Pd, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscope, N_2 adsorption and inductively coupled plasma atomic emission spectroscopy. The N-doped PC-Pd composite exhibited high catalytic activity toward the Suzuki-Miyaura cross-coupling reactions. The yields of the products were in the range of 90%-99%. The catalyst could be readily recycled and reused at least 6 consecutive cycles without a significant loss of its catalytic activity.

关键词： Suzuki-Miyaura coupling reaction Pd catalyst N-Doped nanoporous carbon Metal-organic frameworks

Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao zhao Xuelin Wang Hui Guo Zhenjia Xie Chengjia shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期68卷 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao XIA Jianing LIANG Yuhao JIANG Zhiyang PENG Jiaxu LI Chen XIAO Renyou XU Wenwen WANG Xiantao shang Shiyang LU Dapeng ZHU Hong-Xi LIU Kaihua CAO Weisheng zhao Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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Growth behavior and electronic regulation of Pt on various Mo-based supports for hydrogen evolution electrocatalysis

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Science China Chemistry 2025年

作者： Lulu Chen Yichao Huang Jiajun Wang Meihong Liao Zhiyuan Liu Meiqi Liu Hanqing Cai Lin Wang Lidong Gao Dawei Hu Lianming zhao ning Pu Zhuangjun Fan State Key Laboratory of Chemical Safety School of Materials Science and Engineering China University of Petroleum (East China) School of Mechanical and Electronic Engineering Qingdao Binhai University Qingdao Chuangqi New Energy Catalysis Technology Co.Ltd. Sinopec Research Institute of Petroleum Processing Co.Ltd. Institute of Energy Hefei Comprehensive National Science Center

Insight into the growth behavior and electronic regulation of platinum （Pt） on various transition metal supports is paramount in developing high-performing electrocatalysts for hydrogen evolution reactions （HER）.Herein,we studied the influence of molybdenum-based supports （MoX,X=C,N,P,and S） on the growth behavior and electronic regulation of *** found that the formation energy variations between Pt single atom and clusters on MoX supports play a pivotal role in the growth behavior of ***,the electronic regulation of Pt induced by metal-support interaction may reflect the valence changes of Pt in Pt-MoX/*** Pt-MoC/C catalyst with a moderate valence state of Pt exhibits the best HER activity with an overpotential of 12.0 mV at 10 mA cm-2and a mass activity of 27.1 A mgPt-1,12.3 times as high as that of commercial 20 wt% Pt/*** work provides constructive guidance for the design of high-performance HER catalysts.

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Lipomatous ependymoma with ZFTA:RELA fusion-positive:A case report

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World Journal of Clinical Cases 2025年第1期13卷 48-55页

作者： Xiao-Yu zhao Juan-Han Yu Yi-Hua Wang Yi-Xin Liu Lu Xu Lin Fu ning Yi China Medical University The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Department of Pathology The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Anshan Cancer Hospital Anshan 114000Liaoning ProvinceChina

BACKGROUND Ependymoma with lipomatous differentiation is a rare type of *** ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of central nervous system *** fusion-positive lipomatous ependymoma has not been reported to *** SUMMARY We reported a case of a 15-year-old Chinese male who had a sudden convulsion lasting approximately six *** resonance imaging showed a round cystic shadow of approximately 1.9 cm×1.5 cm×1.9 cm under the right parieto-occipital *** examination showed characteristic perivascular pseudorosettes and adipose differentiation in the ***-chemical staining showed that the tumor cells were negative for cytokeratin,NeuN,Syn and p53,but positive for GFAP,vimentin and S-100 ***-ficant punctate intracytoplasmic EMA immunoreactivity was *** level of Ki-67 was about 5%.Genetic analysis revealed ZFTA:RELA fusion.A cranio-tomy with total excision of the tumor was *** follow-up time was 36 months,no evidence of disease recurrence was found in magnetic resonance *** Based on these findings,the patient was diagnosed as a ependymoma with ZFTA fusion and lipomatous *** case report provides information on the microscopic morphological features of ependymoma with ZFTA fusion and lipomatous differentiation,which can help pathologists to make a definitive diagnosis of this tumor.

关键词： Ependymoma Lipomatous Molecular classification Supratentorial ZFTA:RELA fusion Case report

Nucleation and growth of helium bubble at(110) twist grain boundaries in tungsten studied by molecular dynamics

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Chinese Physics B 2019年第8期28卷 232-240页

作者： Fang-Biao Li Guang Ran ning Gao shang-Quan zhao ning Li College of Energy Xiamen UniversityXiamen 361102China Institute of Modern Physics Chinese Academy of SciencesLanzhou 73000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100094China

Migration of He atoms and growth of He bubbles in high angle twist grain boundaries(HAGBs)in tungsten(W)are investigated by atomic simulation *** energy and free volume(FV)of grain boundary(GB)are affected by the density and structure of dislocation patterns in *** migration energy of the He atom between the neighboring trapping sites depends on free volume along the migration path at grain *** region of grain boundary around the He bubble forms an ordered crystal structure when He bubble grows at certain grain *** He atoms aggregate on the grain boundary plane to form a plate-shape ***,high grain boundary energy(GBE)results in a large volume of He ***,the nucleation and growth of He bubbles in twist grain boundaries depend on the energy of grain boundary,the dislocation patterns and the free volume related migration path on the grain boundary plane.

关键词： tungsten dislocation patterns ordered grain boundary structure plate-shape He bubble

地区新质生产力对企业全要素生产率的影响与机制

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中国流通经济 2025年第1期39卷 100-114页

作者：张树山刘赵宁东北师范大学经济与管理学院吉林长春130117

发展新质生产力是推动经济高质量发展的内在要求和重要着力点。从微观视角出发,考察具有显著差异化特征的地区新质生产力对企业全要素生产率的影响效应及其内在机制,不仅能够为加速形成新质生产力提供精准的政策指引,还能够为经济运行... 详细信息

发展新质生产力是推动经济高质量发展的内在要求和重要着力点。从微观视角出发,考察具有显著差异化特征的地区新质生产力对企业全要素生产率的影响效应及其内在机制,不仅能够为加速形成新质生产力提供精准的政策指引,还能够为经济运行的关键微观基础提供有效改善生产效率的战略指导。基于2012—2022年我国30个省份(未含港澳台藏)和沪深A股上市公司数据,在通过熵值法测算地区新质生产力发展水平的基础上,利用文本分析法、固定效应模型,深入探究地区新质生产力对企业全要素生产率的影响及其机制。研究发现,地区新质生产力能显著提升企业全要素生产率。从机制检验结果来看,地区新质生产力能够通过赋能企业数字技术创新突破、数字技术应用成效以及内外部交易成本降低,进而提高企业全要素生产率,且公司内部治理与市场公平竞争环境的强化均能增强地区新质生产力对企业生产率的提升效应。异质性检验结果表明,在非国有企业、制造业以及胡焕庸线以东地区,地区新质生产力对企业全要素生产率提升作用更加明显。为此,应在因地制宜的原则下培育和发展新质生产力,统筹推进新型基础设施建设,重视并激发数据要素潜能,促进传统产业和新兴产业协调发展;重视企业治理效能提升,优化信息披露机制,强化披露质量,同时鼓励金融机构将公司治理水平纳入信用评估体系,切实提升公司治理能力;努力营造公平竞争的市场环境,严格落实公平竞争审查,维护良好市场秩序与健康竞争生态,以期助力新质生产力的重大战略意义实现。

关键词：新质生产力全要素生产率市场公平竞争公司治理

Global model of plasma-activated water over long time scale:Pulsed discharge and afterglow

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High Voltage 2023年第2期8卷 326-339页

作者： Wenjun ning Hao shang Yiwei Ji Ronghui Li Lihua zhao Xiaolong Huang Shenli Jia College of Electrical Engineering Sichuan UniversityChengduChina School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina

Plasma-activated water(PAW)has been utilised in various application fields,and a deep understanding on the plasma chemistry is the foundation of application-orientated *** this paper,a global model is built to study the chemical properties of PAW produced by a dielectric barrier discharge that is powered by nanosecond voltage *** applied voltage is firstly repeated with 10 kHz frequency for 100 s,and then shut down for 200 s afterglow,providing a long-term evolution regarding the production and consumption of some typical reactive oxygen/nitrogen species(RONS)in *** calculated results agree principally with experimental measurements from *** the pulsed discharge,the water gradually acidises,and the long-lived species accumulate;while in the afterglow,most of the aqueous RONS decay rapidly,except for O_(3aq),NO_(3aq)^(−),H_(2)O_(2aq)and N_(2)O_(aq),which might be the main sources to sustain long-term ***,the effects of applied voltage and gap distance on RONS are *** analyses from Pearson correlation coefficient indicate that gaseous RONS are more sensitive to the gap distance,while the aqueous ones are more sensitive to the voltage amplitude,suggesting the possibility to independently regulating the gaseous and aqueous chemistry.

关键词： gaseous Global providing

Colloidal quantum-dots surface and device structure engineering for high-performance light-emitting diodes

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National Science Review 2017年第2期4卷 170-183页

作者： Yuequn shang Zhijun ning School of Physical Science and Technology Shanghai Tech University shanghai Institute of Ceramics Chinese Academy of Sciences University of Chinese Academy of Sciences

The application of colloidal quantum dots for light-emitting devices has attracted considerable attention in recent years, due to their unique optical properties such as size-dependent emission wavelength, sharp emission peak and high luminescent quantum yield. Tremendous efforts have been made to explore quantum dots for light-emission applications such as light-emitting diodes(LEDs) and light *** performance of quantum-dots-based light-emitting diodes(QD-LEDs) has been increasing rapidly in recent decades as the development of quantum-dots synthesis, surface-ligand engineering and device-architecture optimization. Recently, the external quantum efficiencies of red quantum-dots LEDs have exceeded 20.5% with good stability and narrow emission peak. In this review, we summarize the recent advances in QD-LEDs, focusing on quantum-dot surface engineering and device-architecture optimization.

关键词： colloidal quantum dots light-emitting diodes surface engineering device architecture