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Carbon Energy 2024年第8期6卷 122-133页

作者： jian‐zhao peng Yin‐Long Li Yao‐Ti Cheng Fu‐Zhi Li Bo Cao Qing Wang Xian Yue Guo‐Tao Lai Yang‐Gang Wang Jun Gu Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdongChina Institute for Catalysis Hokkaido UniversitySapporoJapan

Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous *** metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to *** macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom ***–N_(4)site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been *** this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2)*** comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also *** Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic *** ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2).

关键词： ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst

基于驱动力-压力-状态-响应模型的黄河流域甘肃段生态系统健康评价

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生态与农村环境学报 2024年第5期40卷 602-611页

作者：赵建鹏武江民贾腊春曹源西北师范大学地理与环境科学学院甘肃兰州730070

基于驱动力-压力-状态-响应(DPSR)模型和熵权-变异系数综合赋权法对2010—2020年黄河流域甘肃段57个区(县)生态系统健康进行评价,分析各流域及各区(县)生态系统健康等级时空演变及障碍因子,有助于发现生态系统问题并提出合理的管理恢复... 详细信息

基于驱动力-压力-状态-响应(DPSR)模型和熵权-变异系数综合赋权法对2010—2020年黄河流域甘肃段57个区(县)生态系统健康进行评价,分析各流域及各区(县)生态系统健康等级时空演变及障碍因子,有助于发现生态系统问题并提出合理的管理恢复策略。结果表明,2010—2020年黄河流域甘肃段生态系统健康状况整体显著提升,2013—2016年生态系统健康状况较差,2016年后健康状况得到明显改善。黄河干流流域1健康程度较高且健康值变化幅度最大,洮河流域健康状况改善较大,其余流域健康程度低且健康值涨幅较小。在整体准则层层面,黄河流域甘肃段驱动力、压力指数波动增长,状态与响应指数持续上升,表明2010—2020年黄河流域甘肃段生态系统健康状况得到稳定改善。人口增长、人均水资源量、建设用地比例和工业固体废物综合利用率等是影响黄河流域甘肃段生态系统健康等级变化的主要因素。优化土地利用、促进人口均衡分布、推动水资源均衡分配以及加强生态环境保护与修复是促进黄河流域甘肃段绿色发展与生态屏障建设的有效措施。

关键词：驱动力-压力-状态-响应模型生态系统健康熵权-变异系数综合赋权黄河流域甘肃段

Sphericities of non-spherical objects

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Particuology 2012年第1期10卷 97-104页

作者： Teng Li Shuixiang Li jian zhao peng Lu Lingyi Meng Department of Mechanics ＆Aerospace Engineering College of Engineering Peking University Beijing 100871 China

Sphericity, as one of the most important shape parameter for non-spherical objects, is extensively applied in evaluating the porosity or packing density of particles. In this paper, the sphericities of common non- spherical objects are deduced and investigated. Maximum sphericities and optimum shapes of these objects are presented as well. A decreasing order of sphericity from sphere （1.0） to regular tetrahedron （0.671） for objects with constant sphericity is given. Similar trends are found in most sphericity-aspect ratio relationships, which exhibit single Peak and the sphericity increases with the growth of aspect ratio before the peak point and decreases afterward. The peak loci of aspect ratio are all around 1.0 which makes the shape approaching to a sphere. The information in the paper could be useful as literature for general application.

关键词： SphericityAspect ratioNon-spherical particleOptimum shape

Maximum packing densities of basic 3D objects

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Chinese Science Bulletin 2010年第2期55卷 114-119页

作者： LI ShuiXiang zhao jian LU peng XIE Yu State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University Beijing 100871 China

Numerical simulation results show that the upper bound order of random packing densities of basic 3D objects is cube (0.78) > ellipsoid (0.74) > cylinder (0.72) > spherocylinder (0.69) > tetrahedron (0.68) > cone (0.67) > sphere (0.64), while the upper bound order of ordered packing densities of basic 3D objects is cube (1.0) > cylinder and spherocylinder (0.9069) > cone (0.7854) > tetrahedron (0.7820) > ellipsoid (0.7707) > sphere (0.7405); these two orders are significantly different. The random packing densities of ellipsoid, cylinder, spherocylinder, tetrahedron and cone are closely related to their shapes. The optimal aspect ratios of these objects which give the highest packing densities are ellipsoid (axes ratio = 0.8:1:1.25), cylinder (height/diameter = 0.9), spherocylinder (height of cylinder part/diameter = 0.35), tetrahedron (regular tetrahedron) and cone (height/bottom diameter = 0.8).

关键词：三维物体堆积密度随机堆积四面体数值模拟封装密度立方体圆柱体

Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin Composites by Interfacially Enriched Distribution of Nano-Starch Crystals

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 289-296页

作者： Yanpeng Wei Jiale zhao jian Zhuang peng Zhang Zhiwu Han College of Biological and Agricultural Engineering Jilin UniversityChangchun 130025China Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130025China Weichai Lovol Heavy Industry Co. LTDWeifang 261031China

Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength,designability,good dimensional stability and ease of large-area monolithic ***,the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy *** paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals,which are highly yield and ***,in this paper,corn starch nanocrystals(SNC)were prepared by hydrolysis,and were deposited on the surface of basalt fibers by electrostatic *** that,in order to maximize the modification effect of nano-starch crystals on the interface,the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding *** test results shown that the addition of basalt fibers alone led to a reduction in the strength of the *** of 0.1 wt%SNC on the surface of basalt fibers can make the strength consistent with pure epoxy *** the adsorption amount of SNC reached 0.5 wt%,the tensile strength of the samples was 23.7%higher than that of pure epoxy *** is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin,which distorts the originally smooth interface,leading to increased stress concentration and the development of *** enhances the binding of basalt *** conclusions of this paper can provide an effective,simple,low-cost and non-polluting method of interfacial enhancement modification.

关键词： Basalt fibres Epoxy resin Fibre reinforced composites Starch nanocrystals Eco-friendly

Numerical simulation analysis of wind field above pavement surface in different landforms by computational fluid dynamics approach

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 559-573页

作者： jian Ouyang zhao jiang Leiyu Ye Jing Li peng Cao School of Civil Engineering and Architecture Hainan UniversityHaikou 570000China School of Transportation and Logistics Dalian University of TechnologyDalian 116024China Hexagon Manufacturing Intelligence(Qingdao)Co. Ltd.Qingdao 266000China China Tower Co. Ltd.Dalian BranchDalian 116024China Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

The temperature and moisture of the pavement structure can be greatly influenced by the wind speed above pavement *** wind speed above pavement surface not only is dominated by the wind speed of atmosphere,but also it is highly related to the landform and buildings around ***,currently there are no studies about the wind field above pavement surface in consideration of the effect of the landform and buildings.A simulation method,which is combined with geographic information system(GIS),wind data from meteorological observatory and computational fluid dynamics(CFD)software,is employed to study the effect of the landform and the wind speed of atmosphere on the wind field above pavement *** cases are studied,including an urban road,a coastal road and a mountainous ***,the wind field distribution above road surface in different wind directions was studied in our *** indicate that the wind field above pavement surface can be greatly affected by the landforms,buildings and wind *** simulation method can provide reliable results for the wind field above pavement *** maximum relative errors between simulated and measured wind speed can be less than 20%in the analysis of the three *** is recommended that the CFD simulation method is a good tool to accurately know the wind field above pavement surface.

关键词： Wind field above pavement surface Computational fluid dynamics Landforms Geographic information system Simulation

Numerical simulation study on the mold strength of magnetic mold casting based on a coupled electromagnetic-structural method

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China Foundry 2024年第5期21卷 577-587页

作者： Wei-li peng jian-hua zhao Cheng Gu Ya-jun Wang College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

The properties of the magnetic mold in magnetic mold casting directly determine the quality of the final cast *** this study,the magnetic mold properties in magnetic mold casting,were studied utilizing a coupled electromagnetic-structural method through numerical *** study investigated key factors including equivalent stress,the distribution of tensile and compressive stresses,and the area ratio of tensile *** compared molds made entirely of magnetic materials with those made partially of magnetic *** results indicate that as current increases from 4 A to 8 A,both the initial magnetic mold and the material-replaced magnetic mold initially show an increasing trend in equivalent stress,tensile-compressive stress,and the area ratio of tensile stress,peaking at 6 A before *** material replacement,the area ratio of tensile stress at 6 A decreases to 19.84%,representing a reduction of 29.72%.Magnetic molds comprising a combination of magnetic and non-magnetic materials exhibit sufficient strength and a reduced area ratio of tensile stress compared to those made entirely from magnetic *** study provides valuable insights for optimizing magnetic mold casting processes and offers practical guidance for advancing the application of magnetic molds.

关键词： magnetic mold casting coupled electromagnetic-structural method numerical simulation stress analysis

Towards Effective Author Name Disambiguation by Hybrid Attention

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Journal of Computer Science & Technology 2024年第4期39卷 929-950页

作者： Qian Zhou Wei Chen peng-peng zhao An Liu Jia-Jie Xu jian-Feng Qu Lei zhao School of Computer Science and Technology Soochow UniversitySuzhou 215006China

Author name disambiguation(AND)is a central task in academic search,which has received more attention recently accompanied by the increase of authors and academic *** tackle the AND problem,existing studies have proposed various approaches based on different types of information,such as raw document features(e.g.,co-authors,titles,and keywords),the fusion feature(e.g.,a hybrid publication embedding based on multiple raw document features),the local structural information(e.g.,a publication's neighborhood information on a graph),and the global structural information(e.g.,interactive information between a node and others on a graph).However,there has been no work taking all the above-mentioned information into account and taking full advantage of the contributions of each raw document feature for the AND problem so *** fill the gap,we propose a novel framework named EAND(Towards Effective Author Name Disambiguation by Hybrid Attention).Specifically,we design a novel feature extraction model,which consists of three hybrid attention mechanism layers,to extract key information from the global structural information and the local structural information that are generated from six similarity graphs constructed based on different similarity coefficients,raw document features,and the fusion *** hybrid attention mechanism layer contains three key modules:a local structural perception,a global structural perception,and a feature ***,the mean absolute error function in the joint loss function is used to introduce the structural information loss of the vector *** results on two real-world datasets demonstrate that EAND achieves superior performance,outperforming state-of-the-art methods by at least+2.74%in terms of the micro-F1 score and+3.31%in terms of the macro-F1 score.

关键词： author name disambiguation multiple-feature information hybrid attention pruning strategy structural information loss of vector space

Highly selective adsorption of rhenium by amyloid-like protein material

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Science China(Technological Sciences) 2024年第5期67卷 1417-1430页

作者： MUHAMMAD Arif YANG QingMin KANWAL Aisha zhao jian NAWAZ Mohsan REN Hao YANG peng Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Xi’an Key Laboratory of Polymeric Soft Matter International Joint Research Center on Functional Fiber and Soft Smart TextileSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an710119China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an710072China

Rhenium separation from molybdenum in molybdenite minerals and waste leachate has become an emerging *** this challenge,we prepared a set of protein-based alkylamine/alkylammonium salts complexes as extractants for selective uptake of rhenium from molybdenum,where the protein component turned into the insoluble amyloid-like structure when its internal disulfide bonds were reduced,namely phase-transition *** them,the phase-transited lysozyme and methyletrioctyleammonium chloride complex(PTL-N263)exhibited the most efficient adsorption at the alkaline condition for the electrostatic interaction between negatively charged metal ions with positively charged center(R_(4)N^(+))in N263,where negatively charged protein residues hindered the ion exchange of Cl^(-)in N263 for larger size Mo species(Mo_(7)O_(24)^(6-))than smaller size Re species(ReO^(4-)).The adsorption follows the Freundlich model and pseudo-second-order kinetics,which exhibits toplevel adsorption performance with a maximum adsorption capacity of 124 mg/g and a separation factor(β_(Re/Mo))of 2.78×10^(3)for *** adsorption capacity per unit area(57.2 mg/(g m^(2)))is 1.6–41 times higher than previously reported adsorbents,and the cost for adsorbing 1 g of Re(VII)is$1.07,indicating its industrial *** adsorption strategy can be applied to separating Re from Mo in binary solutions and industrial wastewater with other competing ions.

关键词： amyloid phase-transited lysozyme selective adsorption rhenium waste leachate solution

Insights on advanced g‐C_(3)N_(4)in energy storage:Applications,challenges,and future

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Carbon Energy 2024年第4期6卷 22-78页

作者： Xiaojie Yang jian peng Lingfei zhao Hang Zhang Jiayang Li peng Yu Yameng Fan Jiazhao Wang Huakun Liu Shixue Dou School of Nuclear Technology and Chemistry&Biology Hubei Key Laboratory of Radiation Chemistry and Functional MaterialsHubei University of Science and TechnologyXianningChina Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongNorth WollongongNew South WalesAustralia State Key Laboratory of Material Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanChina Institute of Energy Materials Science University of Shanghai for Science and TechnologyShanghaiChina

Graphitic carbon nitride(g‐C_(3)N_(4))is a highly recognized two‐dimensional semiconductor material known for its exceptional chemical and physical stability,environmental friendliness,and pollution‐free *** remarkable properties have sparked extensive research in the field of energy *** review paper presents the latest advances in the utilization of g‐C_(3)N_(4)in various energy storage technologies,including lithium‐ion batteries,lithium‐sulfur batteries,sodium‐ion batteries,potassium‐ion batteries,and *** of the key strengths of g‐C_(3)N_(4)lies in its simple preparation process along with the ease of optimizing its material *** possesses abundant amino and Lewis basic groups,as well as a high density of nitrogen,enabling efficient charge transfer and electrolyte solution ***,the graphite‐like layered structure and the presence of largeπbonds in g‐C_(3)N_(4)contribute to its versatility in preparing multifunctional materials with different dimensions,element and group doping,and conjugated *** characteristics open up possibilities for expanding its application in energy storage *** article comprehensively reviews the research progress on g‐C_(3)N_(4)in energy storage and highlights its potential for future applications in this *** exploring the advantages and unique features of g‐C_(3)N_(4),this paper provides valuable insights into harnessing the full potential of this material for energy storage applications.

关键词： g‐C_(3)N_(4) lithium‐ion batteries lithium‐sulfur batteries potassium‐ion batteries sodium‐ion batteries supercapacitors