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Recent progress of Pt-based oxygen reduction reaction catalysts for proton exchange membrane fuel cells

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Rare Metals 2024年第6期43卷 2444-2468页

作者： Feng Zhan kun-Song Hu Jin-Hua Mai Li-Sheng Zhang Zhen-Guo Zhang huan he Xin-Hua Liu School of Resources Environment and MaterialsGuangxi UniversityNanning530004China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China IDTECH(Suzhou)Co.Ltd Suzhou 215217China Dyson School of Design Engineering Imperial College LondonLondon SW72AZUK

With the increasing consumption of fossil fuels,proton exchange membrane fuel cells(PEMFCs)have attracted considerable attention as green and sustainable energy conversion *** slow kinetics of the cathodic oxygen reduction reaction(ORR)has a major impact on the performance of PEMFCs,and although platinum(Pt)can accelerate the reaction rate of the ORR,the scarcity and high cost of Pt resources still limit the development of ***,the development of low-cost high-performance ORR catalysts is essential for the commercial application and development of *** paper reviews the research progress of researchers on Pt-based ORR catalysts in recent years,including Pt/C catalysts,Pt-based alloy catalysts,Pt-based intermetallic compounds,and Pt-based single-atom catalysts(SACs),with a focus on Pt-based alloy catalysts with different *** described in detail the difficulties and solutions in the research process of various ORR catalysts and explained the principle of their activity enhancement with density functional theory(DFT).In addition,an outlook on the development of Pt-based catalysts is given,and reducing the amount of Pt used and improving the performance of catalysts are the directions to work on in the coming period.

关键词： Pt-based catalysts PEMFCs Pt-based intermetallic compounds Single-atom catalysts

A new 8-connected self-penetrating metal-organic framework based on dinuclear cadmium clusters as secondary building units

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Chinese Chemical Letters 2013年第8期24卷 691-694页

作者： kun-huan he Yun-Wu Li Yong-Qiang Chen Ze Chang Department of Chemistry and Tianjin Key Lab of Metal and Molecule-Based Material ChemistryNankai University

A new metal-organic framework（MOF） based on metal clusters as secondary building units（SBU）,has been synthesized and structurally *** reported MOF presents an interesting 8-connected self-penetrating coordination network based on dinuclear cadmium cluster with a 4^（24）·5·6~3 topology. Moreover,the thermal stability and luminescence property of this compound have been investigated.

关键词： Metal-organic framework Secondary building units Coordination network Luminescence property

An improved analysis method for assessing the nuclear-heating impact on the stability of toroidal field magnets in fusion reactors

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Nuclear Science and Techniques 2024年第6期35卷 163-176页

作者： Yu-Dong Lu Jin-Xing Zheng Xu-Feng Liu huan Wu Jian Ge kun Xu Ming Li Hai-Yang Liu Lei Zhu Fei Liu Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T *** study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal *** the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on *** enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the *** selection streamlines the workload associated with thermal-hydraulic *** approach enables a more efficient and precise evaluation of the temperature margin of TF ***,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems.

关键词： Superconducting magnet Nuclear heating Neutronics Thermal hydraulics

Genomic data and ecological niche modeling reveal an unusually slow rate of molecular evolution in the Cretaceous Eupteleaceae

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Science China(Life Sciences) 2024年第4期67卷 803-816页

作者： kun-Li Xiang Sheng-Dan Wu Lian Lian Wen-Chuang he Dan Peng huan-Wen Peng Xiao-Ni Zhang Hong-Lei Li Jia-Yu Xue Hong-Yan Shan Gui-Xia Xu Yang Liu Zhi-Qiang Wu Wei Wang State Key Laboratory of Plant Diversity and Specialty Crops Institute of BotanyChinese Academy of SciencesBeijing 100093China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureKey Laboratory of Synthetic BiologyLaboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China China National Botanical Garden Beijing 100093China State Key Laboratory of Grassland Agro-Ecosystems and College of Ecology Lanzhou UniversityLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Landscape Architecture and Life Science/Institute of Special Plants Chongqing University of Arts and SciencesChongqing 402160China College of Horticulture Academy for Advanced Interdisciplinary StudiesNanjing Agricultural UniversityNanjing 210095China Fairylake Botanical Garden Shenzhen&Chinese Academy of SciencesShenzhen 518004China

Living fossils are evidence of long-term sustained ecological ***,whether living fossils have little molecular changes remains poorly known,particularly in ***,we have introduced a novel method that integrates phylogenomic,comparative genomic,and ecological niche modeling analyses to investigate the rate of molecular evolution of Eupteleaceae,a Cretaceous relict angiosperm family endemic to East *** assembled a high-quality chromosome-level nuclear genome,and the chloroplast and mitochondrial genomes of a member of Eupteleaceae(Euptelea pleiosperma).Our results show that Eupteleaceae is most basal in Ranunculales,the earliest-diverging order in eudicots,and shares an ancient whole-genome duplication event with the other *** document that Eupteleaceae has the slowest rate of molecular changes in the observed *** unusually low rate of molecular evolution of Eupteleaceae across all three independent inherited genomes and genes within each of the three genomes is in association with its conserved genome architecture,ancestral woody habit,and conserved niche *** findings reveal the evolution and adaptation of living fossil plants through large-scale environmental change and also provide new insights into early eudicot diversification.

关键词： conservation genomics eudicots evolutionary rates niche conservatism phylogenomics

Creep rupture life predictions for Ni-based single crystal superalloys with automated machine learning

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Rare Metals 2024年第6期43卷 2884-2890页

作者： Chang-Lu Zhou Rui-Hao Yuan Wei-Jie Liao Ting-huan Yuan Jiang-kun Fan Bin Tang Ping-Xiang Zhang Jin-Shan Li Turab Lookman State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Chongqing Innovation Center Northwestern Polytechnical UniversityChongqing 401120China AiMaterials Research LLC Santa FeNM 87501USA

The state of the art for data-driven creep rupture life predictions incorporates microstructural and deformation characteristics into machine ***,the microstructures and deformation mechanisms for unknown alloys are inaccessible and uncertain before experiments are carried out,and therefore prevents extrapolations of the learned models.

关键词： deformation life creep

An alfalfa MYB-like transcriptional factor MsMYBH positively regulates alfalfa seedling drought resistance and undergoes MsWAV3-mediated degradation

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Journal of Integrative Plant Biology 2024年第4期66卷 683-699页

作者： kun Shi Jia Liu huan Liang Hongbin Dong Jinli Zhang Yuanhong Wei Le Zhou Shaopeng Wang Jiahao Zhu Mingshu Cao Chris S.Jones Dongmei Ma Zan Wang College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Institute of Animal Sciences Chinese Academy of Agricultural SciencesBeijing 100193China AgResearch Grasslands Research Centre Palmerston North 4442New Zealand International Livestock Research Institute Nairobi 00100Kenya School of Ecology and Environment Ningxia UniversityYinchuan 750021China

Drought is a major threat to alfalfa(Medicago sativa L.)*** discovery of important alfalfa genes regulating drought response will facilitate breeding for drought-resistant alfalfa ***,we report a genome-wide association study of drought resistance in *** identified and functionally characterized an MYB-like transcription factor gene(MsMYBH),which increases the drought resistance in *** with the wild-types,the biomass and forage quality were enhanced in MsMYBH overexpressed *** RNA-seq,proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1,MsMCP2,MsPRX1A and MsCARCAB to improve their *** outcomes of such interactions include better water balance,high photosynthetic efficiency and scavenge excess H_(2)O_(2)in response to ***,an E3 ubiquitin ligase(MsWAV3)was found to induce MsMYBH degradation under long-term drought,via the 26S proteasome ***,variable-number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms,and the variation is associated with promoter ***,our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought-resistant *** discovery also offers new insights into the mechanisms of drought resistance in alfalfa.

关键词： alfalfa drought resistance E3 ubiquitin ligase MsMYBH MsWAV3 MYB-like transcriptional factor

Elite,transformable haploid inducers in maize

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The Crop Journal 2024年第1期12卷 314-319页

作者： Brent Delzer Dawei Liang David Szwerdszarf Isadora Rodriguez Gonzalo Mardones Sivamani Elumalai Francine Johnson Samson Nalapalli Rachel Egger Erin Burch Kerry Meier Juan Wei Xiujuan Zhang Huaping Gui Huaibing Jin huan Guo kun Yu Yubo Liu Becky Breitinger Ana Poets Jason Nichols Wan Shi David Skibbe Qiudeng Que Timothy Kelliher Seeds Development Syngenta SeedsJanesvilleWI 53546USA Seeds Research Syngenta Biotechnology China Co.Ltd.Beijing 102206China Centro de Investigación de Cultivos Arica Syngenta R&DArica 1000000Chile Syngenta S.A. Proyecto la SoledadGraneros 2880000Chile Seeds Research Syngenta Crop Protection LLCRTPNC 27709USA Seeds Development Syngenta SeedsSlaterIA 50244USA

The introduction of alleles into commercial crop breeding pipelines is both time consuming and *** technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent *** HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive *** marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid *** show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCheL morphogenetic ***,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk *** strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.

关键词： Zea mays L Doubled haploids Transformation Genome editing QTL

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社交媒体用户隐私素养评价指标体系构建

图书馆论坛 2024年第2期44卷 123-134页

作者：王建亚张欢张坤天津财经大学管理科学与工程学院郑州大学管理学院

社交媒体的广泛运用对用户隐私素养水平提出新挑战,为科学测量用户隐私素养、发现现存问题并开展针对性教育,亟需构建一套系统可量化和操作性强的评价指标体系。文章通过三级编码方法,从已有研究中提取社交媒体用户隐私素养初始评价指标... 详细信息

社交媒体的广泛运用对用户隐私素养水平提出新挑战,为科学测量用户隐私素养、发现现存问题并开展针对性教育,亟需构建一套系统可量化和操作性强的评价指标体系。文章通过三级编码方法,从已有研究中提取社交媒体用户隐私素养初始评价指标,借助德尔菲法进行指标修正,利用层次分析法确定指标权重,构建由隐私意识、隐私知识、隐私边界管理能力、隐私风险管理能力、隐私道德与法律5个一级指标和18个二级指标组成的评价指标体系;根据评价指标权重分析结果,提出了社交媒体用户隐私素养提升策略。

关键词：隐私素养评价指标社交媒体隐私保护

基于共享孔径技术的低RCS电磁超构表面天线设计

同方期刊数据库博看期刊评论

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物理学报 2024年第12期73卷 159-169页

作者：李桐杨欢欢李奇廖嘉伟高坤季轲峰曹祥玉空军工程大学信息与导航学院西安710077 中国空间技术研究院系统创新中心西安710100

提出一种基于共享孔径技术设计低雷达散射截面(radar cross section,RCS)电磁超构表面天线的新方法.该方法首先设计具有低RCS性能的超构表面,然后借鉴共享孔径技术思想,将超构表面和传统天线的辐射结构直接共享口径紧密排列,得到新型低... 详细信息

提出一种基于共享孔径技术设计低雷达散射截面(radar cross section,RCS)电磁超构表面天线的新方法.该方法首先设计具有低RCS性能的超构表面,然后借鉴共享孔径技术思想,将超构表面和传统天线的辐射结构直接共享口径紧密排列,得到新型低RCS天线结构,并结合电流分析和局部结构修正,优化天线的辐射性能,最终同时实现天线的良好辐射和宽带低RCS性能.为了阐明该方法,基于极化旋转机理设计了一款低RCS超构表面,采用共享孔径思想和电流分析,得到了一款宽带低RCS超构表面天线,详细分析了该天线的工作机理与性能.结果表明:设计的天线在保证较好辐射的同时,实现了超宽带RCS减缩,提出的设计方法摒弃了从天线到低RCS天线的传统设计思路,通过逆向思维,将散射的优化问题转化为辐射的优化问题,不仅实现了天线与超构表面的一体化设计,还显著地降低了低RCS天线优化设计的难度,加速了天线优化进程.

关键词：电磁超构表面天线共享孔径技术低雷达散射截面