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Nano Research 2024年第1期17卷 221-227页

作者： Yu Zhang Shuting Zhang Mengwei Yuan Yufeng Li Rong Liu Caiyun Nan Chen Chen Engineering Research center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China X-ray diffraction Lab Analytical and Testing CenterBeijing Normal UniversityBeijing 100875China

Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(Li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of Li-O_(2) batteries.Herein,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co site.The Li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)Td site for Li-O_(2) batteries.Theoretical calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate LiO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries.

关键词： lithium oxygen(Li-O_(2))batteries geometrical configuration oxidation state lithium peroxide

A Review on the Security of the Ethereum-Based DeFi Ecosystem

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 69-101页

作者： Yue Xue Dunqiu Fan Shen Su Jialu Fu Ning Hu Wenmao Liu Zhihong Tian Cyberspace Institute of Advanced Technology Guangzhou UniversityGuanzhou510000China Innovation center NSFOCUS Inc.Beijing100089China Engineering Research center of Integration and application of Digital Learning Technology Ministry of EducationBeijing100816China

Decentralized finance(DeFi)is a general term for a series of financial products and services.It is based on blockchain technology and has attracted people’s attention because of its open,transparent,and intermediary free.Among them,the DeFi ecosystem based on Ethereum-based blockchains attracts the most attention.However,the current decentralized financial system built on the Ethereum architecture has been exposed to many smart contract vulnerabilities during the last few years.Herein,we believe it is time to improve the understanding of the prevailing Ethereum-based DeFi ecosystem security issues.To that end,we investigate the Ethereum-based DeFi security issues:1)inherited from the real-world financial system,which can be solved by macro-control;2)induced by the problems of blockchain architecture,which require a better blockchain platform;3)caused by DeFi invented applications,which should be focused on during the project development.Based on that,we further discuss the current solutions and potential directions ofDeFi security.According to our research,we could provide a comprehensive vision to the research community for the improvement of Ethereum-basedDeFi ecosystem security.

关键词： Blockchain smart contract decentralized finance DeFi security

Industry-Oriented Detection Method of PCBA Defects Using Semantic Segmentation Models

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1438-1446页

作者： Yang Li Xiao Wang Zhifan He Ze Wang Ke Cheng Sanchuan Ding Yijing Fan Xiaotao Li Yawen Niu Shanpeng Xiao Zhenqi Hao Bin Gao Huaqiang Wu Department of Internet of Things Technology and application China Mobile Research InstituteBeijing 100053China beijing Advanced Innovation center for Integrated Circuits the School of Integrated CircuitTsinghua UniversityBeijing 100084China SigmaStar Technology Limited Xiamen 361199China IEEE

Automated optical inspection(AOI)is a significant process in printed circuit board assembly(PCBA)production lines which aims to detect tiny defects in PCBAs.Existing AOI equipment has several deficiencies including low throughput,large computation cost,high latency,and poor flexibility,which limits the efficiency of online PCBA inspection.In this paper,a novel PCBA defect detection method based on a lightweight deep convolution neural network is proposed.In this method,the semantic segmentation model is combined with a rule-based defect recognition algorithm to build up a defect detection frame-work.To improve the performance of the model,extensive real PCBA images are collected from production lines as datasets.Some optimization methods have been applied in the model according to production demand and enable integration in lightweight computing devices.Experiment results show that the production line using our method realizes a throughput more than three times higher than traditional methods.Our method can be integrated into a lightweight inference system and pro-mote the flexibility of AOI.The proposed method builds up a general paradigm and excellent example for model design and optimization oriented towards industrial requirements.

关键词： Automated optical inspection(AOI) deep learning defect detection printed circuit board assembly(PCBA) semantic segmentation.

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Effects of Thirty Days Isolation on Attention Networks: A Behavioral and Event-related Potential Study

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Neuroscience Bulletin 2024年第1期40卷 127-132页

作者： Jingda Feng Bin Wu Ziqing Cao Hailong Chen Tianjun Lan Haibo Qin Yusheng Shi Weifen Huang Yinghui Li Department of Aerospace Science and Technology Space Engineering UniversityBeijing 101400China China Astronaut Research and Training center Beijing 100094China State Key Laboratory of Space Medicine Fundamentals and application China Astronaut Research and Training CenterBeijing 100094China School of Psychology Shaanxi Normal UniversityXi'an 710000China

Kear Editor,Individuals in isolated,confined,and extreme environments,such as astronauts,researchers wintering over Antarctica,submarine soldiers,and participants in simulated isolation environment experiments,commonly report difficulty in focusing their attention[1,2].However,current experimental findings from studies conducted in such environments are insufficient to fully support these self-reports of reduced attention.Certain attention-demanding tasks such as simple reaction time(RT)tasks and dual tasks,including primary pursuit tracking and secondary RT,were not affected in space flight experiments[2,3].

关键词： environments submarine winter

Hydrothermal synthesis of polyimide-linked covalent organic frameworks towards ultrafast and stable cathodic sodium storage

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Science China Chemistry 2024年第4期67卷 1300-1310页

作者： Xiya Yang Lei Gong Zhixin Liu Qianjun Zhi Baoqiu Yu Xin Chen Kang Wang Xiaofeng Li Dongdong Qi Jianzhuang Jiang beijing Advanced Innovation center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Redox-active organic materials are capturing growing attention as cathode materials for sustainable alkaline metal ion batteries.However,the storage of Na+in most organic materials-based cathodes is plagued by low capacity and unsatisfying rate performance due to their low active site densities and limited exposed active sites.Herein,two polyimide-linked covalent organic frameworks(COFs),namely HATN-PD-COF and HATN-TAB-COF,were fabricated from hydrothermal synthesis with redoxactive triphenylene-2,3,6,7,10,11-hexacarboxylic acid and aromatic amines as starting materials.Powder X-ray diffraction and electron microscopy analysis indicate the high crystalline nature of these COFs with AA stacking configuration and orderly mesoporous tunnel.N_(2) sorption measurement discloses the permanent porosity of these two COFs with a Brunauer-EmmettTeller surface area of 1,065-1,200 m^(2)g^(-1)and a large pore size of 2.0-3.1 nm.Galvanostatic intermittent titration technique and density functional theory calculations reveal the facile Na+ion diffusion along the mesoporous tunnel of these COFs with a small energy barrier of 0.13-0.40 e V.In particular,the as-prepared COFs based-cathodes show ultrafast and stable Na+storage associated with their conjugated electronic structure,highly ordered mesoporous tunnel,robust structure,and redox-active C=N/C=O-rich framework as exemplified by the high reversible capacity of 210 m A h g^(-1)at 200 m A g^(-1),record-high rate performance(195 m A h g^(-1)at a high current density of 10,000 m A g^(-1))among organic electrodes and the capacity retention of nearly 91%at 10,000 m A g^(-1)after 7,000 cycles for HATN-PD-COF.

关键词： covalent organic framework sodium ion battery cathode high rate organic electrode

Enrichment of anammox biomass during mainstream wastewater treatment driven by achievement of partial denitrification through the addition of bio-carriers

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Journal of Environmental Sciences 2024年第3期137卷 181-194页

作者： Yuqing Ma Bo Wang Xiaodi Li Shuo Wang Wen Wang Yongzhen Peng National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Engineering Research Center of BeijingBeijing University of TechnologyBeijing 100124China

Anammox is widely considered as the most cost-effective and sustainable process for nitrogen removal.However,how to achieve the enrichment of anammox biomass remains a challenge for its large-scale application,especially in mainstream wastewater treatment.In this study,the feasibility of enrichment of anammox biomass was explored through the realization of partial denitrification and the addition of bio-carriers.By using ordinary activated sludge,a sequencing batch reactor(SBR)followed by an up-fow anaerobic sludge bed(UASB)was operated at 25±2℃ for 214 days.The long-term operation was divided into five phases,in which SBR and UASB were started-up in Phases I and II,respectively.By eliminating oxygen and adjusting the infow ratios in Phases III-V,advanced nitrogen removal was achieved with the effuent total nitrogen being 4.7 mg/L and the nitrogen removal efficiency being 90.5%in Phase V.Both in-situ and ex-situ activity tests demonstrated the occurrence of partial denitrification and anammox.Moreover,16S rRNA high-throughput sequencing analysis revealed that Candidatus Brocadia was enriched from below the detection limit to in biofilms(0.4%in SBR,2.2%in UASB)and the foc sludge(0.2%in SBR,1.3%in UASB),while Thauera was mainly detected in the foc sludge(8.1%in SBR,8.8%in UASB),which might play a key role in partial denitrification.Overall,this study provides a novel strategy to enrich anammox biomass driven by rapid achievement of partial denitrification through the addition of bio-carriers,which will improve large-scale application of anammox processes in mainstream wastewater treatment.

关键词： Enrichment Anammox biomass Bio-carriers Partial denitrification Mainstream wastewater

Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations

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Journal of Energy Chemistry 2024年第6期93卷 299-305,I0008页

作者： Legeng Yu Nan Yao Yu-Chen Gao Zhong-Heng Fu Bo Jiang Ruiping Li Cheng Tang Xiang Chen Tsinghua center for Green Chemical Engineering Electrification(CCEE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China beijing Advanced Innovation center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data center University of Science and Technology BeijingBeijing 100083China Ordos Carbon Neutral Research and application Co. Ltd.Ordos 017010Inner Mongoli1China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan University2066 Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea

Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very lacking.Herein,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an example.An interface model was developed,incorporating the electrode potential and atom electronegativities.As a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic level.Specifically,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,respectively.Such preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+deposition.This CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.

关键词： Lithium batteries Graphite N-doping Electric double layer Molecular dynamics Constant potential method Electrode potential

Metal-organic frameworks and their composites for advanced lithium-ion batteries:Synthesis,progress and prospects

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Journal of Energy Chemistry 2024年第2期89卷 449-470,I0011页

作者： Chengcai Liu Borong Wu Tao Liu Yuanxing Zhang Jingwen Cui Lingjun Huang Guoqiang Tan Ling Zhang Yuefeng Su Feng Wu School of Material Science and Engineering Beijing Institute of TechnologyBeijing 100081China Chonging Innovation center Beijing Institute of TechnologyChongqing 401120China Collaborative Innovation center of Electric Vehicles in beijing Beijing 100081China

Metal-organic frameworks(MOFs)are among the most promising materials for lithium-ion batteries(LIBs)owing to their high surface area,periodic porosity,adjustable pore size,and controllable chemical composition.For instance,their unique porous structures promote electrolyte penetration,ions transport,and make them ideal for battery separators.Regulating the chemical composition of MOF can introduce more active sites for electrochemical reactions.Therefore,MOFs and their related composites have been extensively and thoroughly explored for LIBs.However,the reported reviews solely include the applications of MOFs in the electrode materials of LIBs and rarely involve other aspects.A systematic review of the application of MOFs in LIBs is essential for understanding the mechanism of MOFs and better designing related MOFs battery materials.This review systematically evaluates the latest developments in pristine MOFs and MOF composites for LIB applications,including MOFs as the main materials(anode,cathode,separators,and electrolytes)to auxiliary materials(coating layers and additives for electrodes).Furthermore,the synthesis,modification methods,challenges,and prospects for the application of MOFs in LIBs are discussed.

关键词： Metal-organic frameworks Electrodes Electrolytes Separators Lithium-ion batteries

Single-cell mass spectrometry studies of drug metabolism heterogeneity and primary resistance to gefitinib in non-small cell lung cancer cells

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Chinese Chemical Letters 2024年第2期35卷 436-440页

作者： Guizhen Zhu Yaoyao Zhao Wenmei Zhang Yuanyuan Wu Yuanxing Liu Guangsheng Guo Xiayan Wang Zhihong Liu center of Excellence for Environmental Safety and Biological Effects Beijing Key Laboratory for Green Catalysis and SeparationDepartment of ChemistryBeijing University of TechnologyBeijing 100124China Minzu University of China Beijing 100081China Key Laboratory for the Synthesis and application of Organic Functional Molecules College of Health Science and EngineeringHubei UniversityWuhan 430062China

Patients with epidermal growth factor receptor(EGFR)wild-type non-small cell lung cancer(NSCLC)often show primary resistance to gefitinib therapy.It is thus necessary to study the metabolism of gefitinib in NSCLC cells to comprehensively reveal the reasons for the primary resistance of tumors.Herein,we develop a platform for studying drug metabolism heterogeneity based on single-cell mass spectrometry(sDMH-scMS)by integrating living-cell electrolaunching ionization MS(ILCEI-MS)and high-performance liquid chromatography-MS(HPLC-MS)analysis,and the primary resistance of NSCLC cells to gefitinib was studied using this platform.The ILCEI-MS analysis showed that approximately 11.9%of NSCLC single cells contained the gefitinib metabolite M11;HPLC-MS detection diluted the intensity of M11 in subpopulations and concealed the heterogeneity of drug metabolism in tumor single cells.The intensity of gefitinib in EGFR wild-type A549 cells was markedly lower than in mutant PC9 cells,and the intensity of gefitinib metabolites was significantly higher than in PC9 cells,suggesting that the primary resistance of NSCLC cells is related to gefitinib metabolism.Moreover,the combination of gefitinib and the drug-metabolizing enzyme inhibitorα-naphthoflavone was shown to overcome the primary resistance of the NSCLC cells.Overall,the results of this study are expected to be applicable for clinical drug resistance diagnosis and treatment at the single-cell level.

关键词： Single-cell mass spectrometry Drug metabolism Non-small cell lung cancer Gefitinib Primary resistance

Innovative insights into extrachromosomal circular DNAs in gynecologic tumors and reproduction

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Protein & Cell 2024年第1期15卷 6-20页

作者： Ning Wu Ling Wei Zhipeng Zhu Qiang Liu Kailong Li Fengbiao Mao Jie Qiao Xiaolu Zhao State Key Laboratory of Female Fertility Promotion Center for Reproductive MedicineDepartment of Obstetrics and GynecologyCenter for Reproductive MedicinePeking University Third HospitalBeijing 100191China National Clinical Research center for Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China Key Laboratory of Assisted Reproduction(Peking University) Ministry of EducationBeijing 100191China beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China Institute of Medical Innovation and Research Peking University Third HospitalBeijing 100191China Cancer center Peking University Third HospitalBeijing 100191China Department of Biochemistry and Biophysics Beijing Key Laboratory of Protein Posttranslational Modifications and Cell FunctionSchool of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China beijing Advanced Innovation center for Genomics Beijing 100191China Peking-Tsinghua center for Life Sciences Peking UniversityBeijing 100191China

Originating but free from chromosomal DNA,extrachromosomal circular DNAs(eccDNAs)are organized in circular form and have long been found in unicellular and multicellular eukaryotes.Their biogenesis and function are poorly understood as they are characterized by sequence homology with linear DNA,for which few detection methods are available.Recent advances in high-throughput sequencing technologies have revealed that eccDNAs play crucial roles in tumor formation,evolution,and drug resistance as well as aging,genomic diversity,and other biological processes,bringing it back to the research hotspot.Several mechanisms of eccDNA formation have been proposed,including the breakage-fusion-bridge(BFB)and translocation-deletion-amplification models.Gynecologic tumors and disorders of embryonic and fetal development are major threats to human reproductive health.The roles of eccDNAs in these pathological processes have been partially elucidated since the first discovery of eccDNA in pig sperm and the double minutes in ovarian cancer ascites.The present review summarized the research history,biogenesis,and currently available detection and analytical methods for eccDNAs and clarified their functions in gynecologic tumors and reproduction.We also proposed the application of eccDNAs as drug targets and liquid biopsy markers for prenatal diagnosis and the early detection,prognosis,and treatment of gynecologic tumors.This review lays theoretical foundations for future investigations into the complex regulatory networks of eccDNAs in vital physiological and pathological processes.

关键词： extrachromosomal circular DNAs gynecologic tumors reproduction liquid biopsy non-invasive prena-tal testing