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Pb induced dislocation defects of PtCo systems: Strain-triggered oxygen reduction reaction for PEMFC

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Nano Research 2024年第4期17卷 2462-2472页

作者： chun jin Qiheng Wang jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

Design and development of advanced electrocatalysts with high performance and low Pt consumption are crucial for reducing the kinetic energy barrier of the cathode oxygen reduction reaction(ORR)and improving the efficiency of proton exchange membrane fuel cells(PEMFC).In this study,we demonstrate a Pb-modulated PtCo system for efficient ORR,in which the inclusion of Pb in ternary alloys induces dislocation defects due to the significant difference in atomic ***-PtCoPb was confirmed to exhibit significantly higher ORR activity and stability in acidic *** practical PEMFC applications,it outperforms the corresponding commercial Pt/C with a mass activity of 0.58 A·mgPt^(-1),making it a promising alternative to state-of-the-art Pt-based *** combination of experimental results and density functional theory(DFT)calculations offers valuable atomic-level insights into the dislocation *** with a larger atomic radius is located in the lattice stretching region below the dislocation slip plane,forming a structure similar to a Cottrell atmosphere,which reduces the dislocation energy and puts the system in a lower energy *** Cottrell atmosphere pins the dislocation structure and stabilizes the ternary *** adjusting the amount of added Pb,a moderate level of dislocation density induces a tuned strain effect,thereby enhancing the electrocatalytic mechanism by optimizing the electronic structure of the alloy surface and the adsorption and desorption of oxygen *** work provides valuable insights into the design and development of lattice dislocation defect structures to trigger strain effects for improving ORR performance.

关键词： dislocation defect strain effect Pb-modulated oxygen reduction reaction

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

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Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： Chao Qi Jianqin yin Zhicheng Zhang jin Tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D *** graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud *** point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual *** address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given ***,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point ***,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different *** dynamically splits and merges point groups,resulting in a scene graph with high *** show that our methods outperform other baseline *** output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

Molecular Characteristics of Cephalosporin-Resistant Neisseria gonorrhoeae Strains in China:A Retrospective Study

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International Journal of Dermatology and Venereology 2024年第2期7卷 78-83页

作者： jin Zhang Xiao-Yu Zhu jing-Wei Liu Yue-Ping yin Shao-chun Chen Reference Laboratory for STD Control Hospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences&Peking Union Medical CollegeNanjingJiangsu 210042China National Center for STD Control Chinese Center for Disease Control and PreventionNanjingJiangsu 210042China

Objective:An increasing level of antimicrobial resistance to extended-spectrum cephalosporins has been reported,so we conducted this study to investigate the molecular characteristics of cephalosporin resistant Neisseria gonorrhoeae(NG)strains isolated from China Gonococcal Antimicrobial Resistance Surveillance Programme(China-GRSP).Methods:In total,2,038 NG isolates were collected from the China-GRSP between 2015 and *** multiantigen sequence typing(NG-MAST),multilocus sequence typing(MLST),and NG sequence typing for antimicrobial resistance(NG-STAR)were used to determine characteristics and resistant determinants of cephalosporin-resistant *** results are described as ***:Seventy-four(3.6%)cephalosporin-resistant isolates were ***_(ST7363)was the most prevalent MLST among cefixime-resistant(CFX-R)isolates,whereas MLST_(ST7365)(n=8)in was the most prevalent sequence type among ceftriaxone-resistant(CRO-R)***-R strains were mainly associated with penA-X(n=27,44.3%),penA-XIII(n=6,9.8%),penA-XVIII(n=5,8.2%),and CRO-R strains were mainly related to penA-XVIII(n=10,25.6%),penA-43(n=9,23.1%),penA-XIII(n=7,17.9%).Conclusion:The main conclusion of this study is that the predominant cephalosporin-resistant clones in China include locally emerged and imported *** CFX-R and CRO-R strains are primarily related to penA mutations,and their predominant genotypes are *** the increase in international travel,tracking high-risk-resistant clones and identifying outbreaks and their associations with epidemiological characteristics are critical to improve public health.

关键词： gonorrhea resistance cephalosporin cefixime ceftriaxone

Proteomics Study of Benzene Metabolite Hydroquinone Induced Hematotoxicity in K562 Cells

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Biomedical and Environmental Sciences 2024年第4期37卷 341-353页

作者： jin Yi Shan YI Zong chun ZHANG Yu jing RONG Long YU chun Hong School of Biological Science and Medical Engineering Beihang UniversityBeijing 100191China School of Engineering Medicine Beihang UniversityBeijing 100191China

Objective Hydroquinone(HQ),one of the phenolic metabolites of benzene,is widely recognized as an important participant in benzene-induced ***,there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn’t been fully understood *** In this study,we treated K562 cells with 40μmol/L HQ for 72 h,examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring(PRM),and performed bioinformatics analysis to identify interaction *** One hundred and eighty-seven upregulated differentially expressed proteins(DEPs)and 279 downregulated DEPs were identified in HQ-exposed K562 cells,which were involved in neutrophilmediated immunity,blood microparticle,and other GO terms,as well as the lysosome,metabolic,cell cycle,and cellular senescence-related *** on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways,we constructed the network of protein interactions and determined 6 DEPs(STAT1,STAT3,CASP3,KIT,STAT5B,and VEGFA)as main hub proteins with the most interactions,among which STATs made a central impact and may be potential biomarkers of HQ-induced *** Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification.

关键词： Hydroquinone Proteomics Hematotoxicity K562 cells

Direct enantioselective reduction of C=C bond of β-polyfluoro-alkylated enones via asymmetric photoredox catalysis

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Science China Chemistry 2024年第6期67卷 2016-2021页

作者： Linghong Zhang jin Ma Xu Ban Xiaowei Zhao Yanli yin Zhiyong Jiang Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province Henan UniversityKaifeng475004China School of Chemistry and Chemical Engineering Henan Normal UniversityPingyuan LaboratoryXinxiang453007China College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou450001China

Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric ***,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the ***,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.

关键词： photoredox catalysis Br?nsted acids asymmetric reduction enantioselective protonation azaarenes

Superior Anodic Lithium Storage in Core-Shell Heterostructures Composed of Carbon Nanotubes and Schiff-Base Covalent Organic Frameworks

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 150-157页

作者： Jiang, Nan Qi, Mengpei Jiang, Yalong Fan, yin jin, Shiwei Yang, yingkui South Cent Minzu Univ Sch Chem & Mat Sci Wuhan 430074 Peoples R China Wuhan Text Univ State Key Lab New Text Mat & Adv Proc Technol Wuhan 430200 Peoples R China

Covalent organic frameworks (COFs) after undergoing the superlithiation process promise high-capacity anodes while suffering from sluggish reaction kinetics and low electrochemical utilization of redox-active sites. Herein, integrating carbon nanotubes (CNTs) with imine-linked covalent organic frameworks (COFs) was rationally executed by in-situ Schiff-base condensation between 1,1 '-biphenyl]-3,3 ',5,5 '-tetracarbaldehyde and 1,4-diaminobenzene in the presence of CNTs to produce core-shell heterostructured composites (CNT@COF). Accordingly, the redox-active shell of COF nanoparticles around one-dimensional conductive CNTs synergistically creates robust three-dimensional hybrid architectures with high specific surface area, thus promoting electron transport and affording abundant active functional groups accessible for electrochemical utilization throughout the whole electrode. Remarkably, upon the full activation with a superlithiation process, the as-fabricated CNT@COF anode achieves a specific capacity of 2324 mAh g-1, which is the highest specific capacity among organic electrode materials reported so far. Meanwhile, the superior rate capability and excellent cycling stability are also obtained. The redox reaction mechanisms for the COF moiety were further revealed by Fourier-transform infrared spectroscopy in conjunction with X-ray photoelectron spectroscopy, involving the reversible redox reactions between lithium ions and C=N groups and gradual electrochemical activation of the unsaturated C=C bonds within COFs. Coupling conductive carbon nanotubes with redox-active imine-linked covalent organic frameworks generates core-shell heterostructures capable of building 3D hierarchical architectures with fully exposed active sites for boosting anodic lithium storage. image

关键词： heterostructured anode core-shell nanostructures carbon nanotubes polymeric Schiff-bases covalent organic frameworks BATTERIES

Gradient-based algorithms for multi-objective bi-level optimization

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Science China Mathematics 2024年第6期67卷 1419-1438页

作者： Xinmin Yang Wei Yao Haian yin Shangzhi Zeng jin Zhang National Center for Applied Mathematics in Chongqing Chongqing401331China School of Mathematical Sciences Chongqing Normal UniversityChongqing401331China Department of Mathematics Southern University of Science and TechnologyShenzhen518055China National Center for Applied Mathematics Shenzhen Shenzhen518000China Department of Mathematics and Statistics University of VictoriaVictoriaBCV8W 2Y2Canada

Multi-objective bi-level optimization(MOBLO)addresses nested multi-objective optimization problems common in a range of ***,its multi-objective and hierarchical bi-level nature makes it notably ***-based MOBLO algorithms have recently grown in popularity,as they effectively solve crucial machine learning problems like meta-learning,neural architecture search,and reinforcement ***,these algorithms depend on solving a sequence of approximation subproblems with high accuracy,resulting in adverse time and memory complexity that lowers their numerical *** address this issue,we propose a gradient-based algorithm for MOBLO,called gMOBA,which has fewer hyperparameters to tune,making it both simple and ***,we demonstrate the theoretical validity by accomplishing the desirable Pareto *** experiments confirm the practical efficiency of the proposed method and verify the theoretical *** accelerate the convergence of gMOBA,we introduce a beneficial L2O(learning to optimize)neural network(called L2O-gMOBA)implemented as the initialization phase of our gMOBA *** results of numerical experiments are presented to illustrate the performance of L2O-gMOBA.

关键词： multi-objective bi-level optimization convergence analysis Pareto stationary learning to optimize

Optimization of territorial space layout in China

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Journal of Geographical Sciences 2024年第9期34卷 1719-1738页

作者： DONG yin jin Gui DENG Xiangzheng Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China School of Economics and Management China University of GeosciencesWuhan 430079China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China

The evolution of territorial space is intrinsically linked to economic growth, societal welfare, and ecological preservation. In the context of escalating spatial conflicts and stringent resource limitations, resource efficiency has emerged as a fundamental pillar for the scientific optimization of territorial space layout. Drawing upon resource efficiency metrics from cities nationwide, this study constructs scenarios for territorial space development and conservation, assesses developmental capacity under varying preferences, and subsequently delineates strategic blueprints using an integrated “point-axis-area” approach. The findings reveal the following:(1) Resource efficiency in China has witnessed a consistent uptick, yet remains modest overall, with marked regional disparities.(2) Throughout the investigation period, developmental capacity has seen progressive enhancement, with a pronounced capacity in scenarios favoring development, radiating axially from urban conglomerates.(3) The layout of pivotal points and developmental axes has transitioned from a “tri-pillar” to a diamond configuration, with the coastal corridor, Harbin-Beijing-Guangzhou corridor, and the corridor along the Yangtze River standing out.(4) Strategic points progressively converge along key axes, whereas dominant regions exhibit clear differentiation on either side of the Hu Huanyong Line. By integrating elements of the territorial spatial structure,this paper proposes blueprints for “five horizontal and three vertical zones with eight cores and three areas,” “four horizontal and three vertical zones with six cores and three areas,”and “three horizontal and four vertical zones with five cores and three areas,” corresponding to scenarios of prioritizing development, status quo maintenance, and prioritizing conservation, respectively. The outcomes of this research offer a technical foundation and theoretical guidance for the pursuit of high-quality territorial space development and a vision

关键词： territorial space resource efficiency development and conservation developmental capacity territorial space blueprints China

Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging

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Green Energy & Environment 2024年第5期9卷 927-936页

作者： Rumeng Xu chunchun.yin jingxuan You jinming Zhang Qinyong Mi jin Wu Jun Zhang CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences(CAS)Beijing100190China University of Chinese Academy of Sciences Beijing100049China

Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which signiﬁcantly affect the overall degradation performance of *** is imperative and attractive to develop biodegradable functional ***,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose *** natural cellulose and cinnamic acid were as raw *** reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalﬂow behavior but also good biodegradability,which solves the conﬂict between the thermoplasticity and biodegradability in cellulose-based *** glass transition temperature(T_(g))and thermalﬂow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,*** CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 ***,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high ***,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.

关键词： Thermoplastic coating Bio-degradable adhesive Natural products Cellulose Eco-friendly packaging