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Rational design of graphyne-based dual-atom site catalysts for CO oxidation

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Nano Research 2023年第1期16卷 343-351页

作者： zhenwei zhang Liang zhang Xiaoyang Wang Yuan Feng Xiangwen Liu Wenming Sun Department of Chemistry Beijing Key Laboratory for Optical Materials and Photonic DevicesCapital Normal UniversityBeijing 100048China Linyi Vocational University of Science and Technology(Linyi Institute of Industrial Technology) Linyi 276000China Dassault Systemes(Shanghai)Information Technology Co. Ltd.Shanghai 200120China Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100094China TianHe Supercomputing Center of Huaihai Linyi 276000China

There are increasing concerns about the environmental impact of rising atmospheric carbon monoxide concentrations,thus it is necessary to develop new catalysts for efficient CO oxidation.Based on first-principles calculations,the potential ofγ-graphyne(GY)as substrate for metals in the 4th and 5th periods under single-atom and dual-atoms concentration modes has been systematically investigated.It was found that single-atom Co,Ir,Rh,and Ru could effectively oxidate CO molecules,especially for single Rh.Furthermore,proper atoms concentration could boost the CO oxidation activity by supplying more reaction centers,such as Rh^(2)/GY.It was determined that two Rh atoms in Rh^(2)/GY act different roles in the catalytic reaction:one structural and another functional.Screening tests suggest that substituting the structural Rh atom in the center of acetylenic ring by Co or Cu atom is a possible way to maintain the reaction performance while reducing the noble metal cost.This systemic investigation will help in understanding the fundamental reaction mechanisms on GY-based substrates.We emphasize that properly exposed frontier orbital of functional metal atom is crucial in adsorption configuration as well as entire catalytic performance.This study constructs a workflow and provides valuable information for rational design of CO oxidation catalysts.

关键词： density functional theory calculations CO oxidation single-atom catalyst graphyne dual-atom site catalyst

Hard-carbon hybrid Li-ion/metal anode enabled by preferred mesoporous uniform lithium growth mechanism

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Journal of Energy Chemistry 2024年第1期88卷 252-259,I0006页

作者： Fang Yan Yan Liu Yuan Li Yan Wang Zicen Deng Meng Li zhenwei Zhu Aohan Zhou Ting Li Jingyi Qiu Gaoping Cao Shaobo Huang Biyan Wang Hao zhang School of Chemistry and Biological Engineering University of Science and TechnologyBeijing 100083China Research Institute of Chemical Defense Beijing 100191China College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471023HenanChina National Base for International Science&Technology Cooperation School of ChemistryXiangtan UniversityXiangtan 411105HunanChina Materials and Manufacturing Department Beijing University of TechnologyBeijing 100124China

To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising strategy.In particular,because of the anisotropy of graphite,hybrid anode formed by graphite/Li metal has low transport kinetics and is easy to causes the growth of lithium dendrites and accumulation of dead Li,which seriously affects the cycle life of batteries and even causes safety problems.Here,by comparing graphite with two types of hard carbon,it was found that hybrid anode formed by hard carbon and lithium metal,possessing more disordered mesoporous structure and lithophilic groups,presents better performance.Results indicate that the mesoporous structure provides abundant active site and storage space for dead lithium.With the synergistic effect of this structure and lithophilic functional groups(–COOH),the reversibility of hard carbon/lithium metal hybrid anode is maintained,promoting uniform deposition of lithium metal and alleviating formation of lithium dendrites.The hybrid anode maintains a 99.5%Coulombic efficiency(CE)after 260 cycles at a specific capacity of 500 m Ah/g.This work provides new insights into the hybrid anodes formed by carbon-based materials and lithium metal with high specific energy and fast charging ability.

关键词： Hard carbon/Li metal hybrid anode Mesoporous structure Surface oxygen functional group Fast charging Lithium batteries

A scheme to fix multiple solutions in amplitude analyses

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Chinese Physics C 2024年第5期48卷 8-22页

作者：高原宁荣天泽杨振伟张辰佳张艳席 School of Physics Peking UniversityBeijing 100871China

Decays of unstable heavy particles usually involve the coherent sum of several amplitudes,like in a multiple slit experiment.Dedicated amplitude analysis techniques have been widely used to resolve these amplitudes for better understanding of the underlying dynamics.In special cases where two spin-1/2 particles and two(pseudo-)scalar particles are present in the process,multiple equivalent solutions are found owing to intrinsic symmetries in the summed probability density function.In this study,the problem of multiple solutions is discussed,and a scheme to overcome this problem is proposed by fixing some free parameters.Toys are generated to validate the strategy.A new approach to align the helicities of initial-and final-state particles in different decay chains is also introduced.

关键词： amplitude analysis multiple solutions helicity formalism

The influence of alternating cyclic dynamic loads with different low frequencies on the bio-corrosion behaviors of AZ31B magnesium alloy in vitro

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Bioactive Materials 2022年第1期7卷 263-274页

作者： Linyuan Han zhenwei zhang Jianwei Dai Xuan Li Jing Bai Zhihai Huang Chao Guo Feng Xue Chenglin Chu School of Materials Science and Engineering Southeast UniversityNanjing211189JiangsuChina Jiangsu Key Laboratory for Advanced Metallic Materials Southeast UniversityNanjing211189JiangsuChina School of Materials Engineering Nanjing Institute of TechnologyNanjing211189JiangsuChina Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing211189China

The real physiological environment of human body is complicated with different degrees and forms of dynamic loads applied to implanted medical devices due to the daily activities of the patients,which would have impacts on the degradation behaviors of magnesium alloy implants.In this work,the bio-corrosion behaviors of AZ31B magnesium alloy under alternating cyclic dynamic loads with different low frequencies(0.1-2.5 Hz)were specially investigated.It was found that the bio-degradation performances under external dynamic stressed conditions were much severer than those under unstressed conditions and static loads.The corrosion rates were generally accelerated as the rise of cyclic frequency.Hereby a numerical model for the degradation process of Mg alloy was established.The corrosion current density icorr of Mg alloy and the applied loading frequency f matches a linear relationship of ln icorr∝f,which is the result of interactions between the cyclic alternating load and corrosive environment.This work could provide a theoretical reference and an experimental basis for further researches on the biodegradation behaviors of biomedical materials under dynamic conditions.

关键词： Magnesium alloy Biocorrosion Fatigue Frequency

Statistical Analysis of Articles Published in China CDC Weekly——Worldwide,2019-2020

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China CDC weekly 2021年第31期3卷 669-673页

作者： zhenwei zhang Kun Han Wenhui Shi Editorial Department for Chinese Journal of Preventive Medicine Chinese Medical Association Publishing HouseBeijingChina Division of non-communicable diseases and elderly health management Chinese Center for Disease Control and PreventionBeijingChina

Introduction:This study analyzed views and downloads of articles published in China CDC Weekly from 2019 to 2020 as part of an evaluation of the academic level and quality of the journal.Methods:The study included articles published between November 29,2019 and December 25,2020 and evaluated views and downloads through February 9,2021 using standard bibliometrics.We conducted network analysis with VOSviewer software.Results:There were 283 articles from 101 institutions published in China CDC Weekly during the analysis period,among which 22(21.8%)institutions were overseas institutions.There were 220 unique first authors,with 1.28 articles per first author.There were 2,404,882 views and 58,760 downloads in total.The article with the highest view and download counts had 1,244,826 views and 38,978 downloads.Article types with more than 4,500 views per article were Vital Surveillance,Notes from the Field,and Preplanned Studies.Subjects with more than 3,500 views per article were epidemiology of infectious diseases,epidemiology of non-infectious diseases,and maternal and child health.Articles with descriptive research and articles discussing public health monitoring received more attention,shown by larger average per article page views.Discussion:Study results can help the editorial department improve the journal’s international influence through targeted measures,such as adjusting article types according to view and download analyses and increasing the proportion of international manuscripts selected.

关键词： journal Notes institutions

Population Attributable Fractions for Modifiable Factors of Longevity and Healthy Longevity Among the Late-Elderly Aged 75 Years or Older—China,1998-2018

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China CDC weekly 2023年第2期5卷 25-30,I0001-I0003页

作者： Jinhui Zhou Xiang Gao Yuan Wei Chen Chen Jun Wang zhenwei zhang Xinwei Li Lihong Ye Jiaming Ye Sixin Liu Xiaochang zhang Feng Zhao Juan zhang Virginia Byers Kraus Yuebin Lyu Chen Mao Xiaoming Shi China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina Department of Nutrition and Food Hygiene School of Public HealthInstitute of NutritionFudan UniversityShanghaiChina Department of Epidemiology and Biostatistics School of Public HealthJilin UniversityChangchunJilinChina School of Population Medicine and Public Health Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina Department of Epidemiology School of Public HealthSouthern Medical UniversityGuangzhouGuangdongChina Division of Non-communicable Disease and Aging Health Management Chinese Center for Disease Control and PreventionBeijingChina Duke Molecular Physiology Institute and Division of Rheumatology Department of MedicineDuke University School of MedicineDurhamNorth CarolinaUSA Center for Global Health School of Public HealthNanjing Medical UniversityNanjingJiangsuChina

Summary What is already known about this topic?Limited evidence on healthy longevity was provided in the world,and no studies investigated the fractions of healthy longevity attributed to modifiable factors.What is added by this report?Incidences of longevity and healthy longevity in China are provided.It reveals that the total weighted population attributable fractions for lifestyles and all modifiable factors were 32.8% and 83.7% for longevity,respectively,and 30.4% and 73.4% for healthy longevity,respectively.What are the implications for public health practice?China has a high potential for longevity and healthy longevity.Strategies may be targeted at education and residence in early life as well as healthy lifestyles,disease prevention,and functional optimization in late life.

关键词： prevention attributed education

In vitro bio-corrosion behaviors of biodegradable AZ31B magnesium alloy under static stresses of different forms and magnitudes

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Journal of Magnesium and Alloys 2023年第3期11卷 1043-1056页

作者： Linyuan Han zhenwei zhang Jianwei Dai Xuan Li Jing Bai Zhihai Huang Chao Guo Feng Xue Chenglin Chu School of Materials Science and Engineering Southeast UniversityNanjing 211189China Jiangsu Key Laboratory for Advanced Metallic Materials Southeast UniversityNanjing 211189China School of Materials Engineering Nanjing Institute of TechnologyNanjing 211189China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing 211189China

Biomedical degradable materials would be subjected to different degrees and forms of static stress after being implanted in the human body.In this work,the biocorrosion behaviors of AZ31B magnesium alloy under different stress forms with different magnitudes(20~150MPa)were studied.It was found that the corrosion behaviors at stressed conditions were severer than those at unstressed conditions and corrosion rates were obviously accelerated.The biocorrosion behaviors are more sensitive to the effects of tensile loads than to compressive loads.A biocorrosion numerical model on the degradation process of Mg alloy under static loads was established.The corrosion current density(i_(corr))of Mg alloy and the applied static stress(σ)matches a linear relationship of ln i_(corr)~σwell during the early stage(within 24 hrs)while deviated gradually in the latter period of corrosion.This work could provide a guidance and theoretical reference for further researches on the biocorrosion behaviors and practical clinical applications of the biomedical materials subjected to physiological loads.

关键词： Magnesium alloy Biodegradable alloy Biocorrosion behavior Tensile loading Compressive loading

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糙条对溢洪道连续弯段水流特性的影响

南水北调与水利科技（中英文） 2024年第1期22卷 196-208页

作者：马豪牧振伟张红红新疆农业大学水利与土木工程学院乌鲁木齐830052 新疆水利工程安全与水灾害防治重点实验室乌鲁木齐830052

为探究溢洪道连续弯段水流特性及糙条消能工水力学特性,通过开展27组正交模型试验,结合消能率和超高变异系数筛选最优工况,采用RNG k-ε紊流模型与体积分数法(volume of fluid,VOF)对布设糙条和不布设糙条的溢洪道进行水流特性数值模拟... 详细信息

为探究溢洪道连续弯段水流特性及糙条消能工水力学特性,通过开展27组正交模型试验,结合消能率和超高变异系数筛选最优工况,采用RNG k-ε紊流模型与体积分数法(volume of fluid,VOF)对布设糙条和不布设糙条的溢洪道进行水流特性数值模拟对比研究。结果表明:糙条的布设使溢洪道沿程水深增加且变化剧烈;糙条能够抑制菱形波和折冲水流的产生,通过改善两弯段流态使水面均匀性提升38.0%和44.7%;布设糙条后,两弯段纵向流速均值被降低了45.16%和44.83%,各断面凹岸纵向流速的最大值沿水深下移;糙条的存在加剧了水流紊动,使两弯段纵向紊动强度均值增加了117.98%和71.05%,纵向紊动强度集中在凹岸衰减、凸岸增强,且各断面凹岸的最大值沿水深上移;糙条增大了床面动水压力,减小了两岸压力差,对压力分布形式有显著改善效果,有助于保护底板和边壁不易被冲蚀。研究成果可为溢洪道连续弯段设计及安全运行提供参考。

关键词：糙条消能工溢洪道连续弯段超高变异系数水面均匀性

Spontaneous decoherence of coupled harmonic oscillators confined in a ring

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Science China(Physics,Mechanics & Astronomy) 2018年第4期61卷 17-29页

作者： ZhiRui Gong zhenwei zhang DaZhi Xu Nan Zhao ChangPu Sun College of Physics and Energy Shenzhen UniversityShenzhen 518060China Beijing Computational Science Research Center Beijing 100084China Center for Quantum Technology Research School of PhysicsBeijing Institute of TechnologyBeijing 100081China

We study the spontaneous decoherence of coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry-breaking field or surrounding environment, the quantum superposition state prepared in the relative degrees of freedom gradually loses its quantum coherence spontaneously.This spontaneous decoherence is interpreted by the gauge couplings between the center-of-mass and the relative degrees of freedoms, which actually originate from the symmetries of the ring geometry and the corresponding nontrivial boundary conditions.In particular, such spontaneous decoherence does not occur at all at the thermodynamic limit because the nontrivial boundary conditions become the trivial Born-von Karman boundary conditions when the perimeter of the ring container tends to infinity.Our investigation shows that a thermal macroscopic object with certain symmetries has a chance for its quantum properties to degrade even without applying an external symmetry-breaking field or surrounding environment.

关键词：振荡器泛音戒指集装箱计量器几何学对称自由