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Nano Research 2024年第7期17卷 5914-5921页

作者： chun-Ying Chen qi-Jie Mo Fu-Zhen li Hai-li Song li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Intrinsically asymmetric atomic character regulates piezoelectricity in two-dimensional materials

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Frontiers of physics 2024年第3期19卷 153-162页

作者： Yun-qin li qi-Wen He Dai-Song Tang Xiao Shang Xiao-chun Wang School of Physics Science and Information Technology Liaocheng UniversityLiaocheng 252000China Key Laboratory of Polar Materials and Devices Ministry of EducationDepartment of ElectronicsEast China Normal UniversityShanghai 200241China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

Decreasing of layer thickness causes the decrease of polarization until it disappears due to the existence of depolarization ***,the search for strong piezoelectric materials is highly desirable for multifunctional ultra-thin piezoelectric ***,we propose a common strategy for achieving strong piezoelectric materials through the electronic asymmetry induced by the intrinsically asymmetric atomic character of different chalcogen ***,in the tetrahedral lattice structures,for example,M4X3Y3(M=Pd/Ni,X/Y=S,Se or Te,X≠Y)monolayers are proved to display excellent out-of-plane ***4Se3Te3 possesses the largest piezoelectric coefficient d33 of 61.57 pm/V,which is much larger than that of most 2D *** the electronic asymmetry further increases the out-of-plane piezoelectricity of Janus M4X3Y3 ***,the out-of-plane piezoelectricity is positively correlated with the ratio of electronegativity difference(Red)and the electric dipole moment(P).This work provides alternative materials for energy harvesting nano-devices or self-energized wearable devices,and supplies a valuable guideline for predicting 2D materials with strong out-of-plane piezoelectricity.

关键词： piezoelectricity intrinsically asymmetric atomic character ratio of electronegativity difference electric dipole moment first-principles calculations

Characterization of Changes and Driver Microbes in Gut Microbiota During Healthy Aging Using A Captive Monkey Model

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Genomics, Proteomics & Bioinformatics 2022年第2期20卷 350-365页

作者： Zhi-Yuan Wei Jun-Hua Rao Ming-Tian Tang Guo-An Zhao qi-chun li li-Ming Wu Shao-qiang liu Bi-Hai li Bai-Quan Xiao Xing-Yin liu Jian-Huan Chen Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhou 510260China Laboratory of Genomic and Precision Medicine Wuxi School of MedicineJiangnan UniversityWuxi 214122China Joint Primate Research Center for Chronic Diseases Jiangnan University and Institute of ZoologyGuangdong Academy of SciencesWuxi School of MedicineJiangnan UniversityWuxi 214122China Department of Pathogen-Microbiology Division Nanjing Medical UniversityNanjing 211166China

Recent population studies have significantly advanced our understanding of how age shapes the gut ***,the actual role of age could be inevitably confounded due to the complex and variable environmental factors in human populations.A well-controlled environment is thus necessary to reduce undesirable confounding effects,and recapitulate age-dependent changes in the gut microbiota of healthy *** we performed 16S rRNA gene sequencing,characterized the age-associated gut microbial profiles from infant to elderly crab-eating macaques reared in captivity,and systemically revealed the lifelong dynamic changes of the primate gut *** the most significant age-associated taxa were mainly found as commensals such as Faecalibacterium,the abundance of a group of suspicious pathogens such as Helicobacter was exclusively increased in infants,underlining their potential role in host ***,topology analysis indicated that the network connectivity of gut microbiota was even more agedependent than taxonomic diversity,and its tremendous decline with age could probably be linked to healthy ***,we identified key driver microbes responsible for such age-dependent network changes,which were further linked to altered metabolic functions of lipids,carbohydrates,and amino acids,as well as phenotypes in the microbial *** current study thus demonstrates the lifelong age-dependent changes and their driver microbes in the primate gut microbiota,and provides new insights into their roles in the development and healthy aging of their hosts.

关键词： Age-dependent change Non-human primate Healthy gut microbiota Network connectivity Driver microbe

Theoretical and experimental investigations on single-atom catalysis:Pt1/FeOx for water-gas shift reaction Shan-Fei Wang1,§,Yangyang li2,3,§,Haiyan Wang1,Jin-Xia liang1(✉),chun Zhu1

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Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei Wang Yangyang li Haiyan Wang Jin-Xia liang chun Zhu Botao qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WGS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WGS reaction.

关键词： water-gas shift(WGS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

Electronic structure regulation and built-in electric field synergistically strengthen photocatalytic nitrogen fixation performance on Ti-BiOBr/TiO_(2)heterostructure

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Rare Metals 2024年第3期43卷 1125-1138页

作者： Ru-qi li Yu-Jie Bian chun-Ming Yang li Guo Tao-Xia Ma Chuan-Tao Wang Feng Fu Dan-Jun Wang College of Chemistry and Chemical Engineering Yan’an UniversityYan’an Key Laboratory of Green Catalysis and Quality Improvement and Utilization of Low Rank CoalYan’an716000China

At present,industrial synthetic ammonia was still obtained through the Hubble-Bosch process,with large energy *** is a research hotspot to realize green synthetic ammonia by using solar *** difficulty of photocatalytic ammonia synthesis was that the photo-excited electrons have not enough energy to active N≡*** this study,Ti was doped into BiOBr by one-step hydrothermal method,which was oxidized into TiO_(2)when the doping amount reaches the maximum,in situ forming Ti_(0.31)B_(0.69)OB/TiO_(2)*** from the synergistic effect of Ti doping and S-scheme heterojunction,the synthetic ammonia efficiency of Ti_(0.31)B_(0.69)OB/TiO_(2)-11.96 reached 1.643 mmol·g_(cat)^(-1)at mild conditions and without hole scavenger for up to 7 h,the efficiency of synthetic ammonia is 115 times,10.5 times and 3.3 times of that of BiOBr,Ti_(0.31)B_(0.69)OB and TiO_(2),***,DFT calculation confirms that Ti doping accurately refine the electronic structure of BiOBr,facilitate nitrogen adsorption activation and reduce hydrogenation reaction energy barrier,thus accelerating the reaction kinetics of photocatalytic nitrogen reduction(NRR),Meanwhile,constructing S-scheme heterojunction boosts the separation and transfer of photogenerated electron-hole pairs,improving the reduction ability of electrons in the conduction band of TiO_(2)and the oxidation ability of holes in the valence band of Ti_(0.31)B_(0.69)OB.

关键词： S-scheme heterostructure Electronic structure regulation Built-in electric field Synergistical stren4gthening Photocatalytic nitrogen fixation

Synthesis,Characterization of Polyethylene Ionomers and Their Antibacterial Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1077-1084页

作者： Jia-Jia Wu Fei Wang Peng-qi Wan li Pan chun-Sheng Xiao Zhe Ma Yue-Sheng li Tianjin Key Lab Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Key Lab Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Owing to its high production volume and wide range of application s,polyethylene has gained a great deal of attention,but its low surface energy and non-polar nature have limited its application in some important *** this study,ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate(CH_(3)SO_(3)^(-)),trifluoromethanesulfonate(CF_(3)SO_(3)^(-)),or bis(trifluoromethane)sulfonimide(Tf_(2)N^(-))*** tensile test results showed that the stress-at-break(7.8-25.6 MPa)and the elongation-at-break(445%-847%)of the ionomers could be adjusted by changing the counterion species and the ionic group *** importantly,the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus(***)and Escherichia coli(***).The ionomers bearing Tf_(2)N^(-)exhibited antibacterial activities>99%against both *** and *** when ionic content reached 9.1%.The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties,especially highefficient and broad-spectrum antibacterial ability,exhibiting the potential fo r the application as the antibacterial materials in packaging,medical,and other fields.

关键词： Polyethylene Ionomer Polymerization catalysis Imidazolium Antibacterial material

Exploring the Predominant Factors Influencing the Oxygen Reduction Performance of PtCo/C Catalysts

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Chemical Research in Chinese Universities 2024年第4期40卷 753-760页

作者： li Jinrong YU Xianghui SUN qi PENG Yong CAO Shuang HOU chun-Chao XU qiang College of Chemistry and Chemical Engineering Institute for Sustainable Energy and ResourcesQingdao UniversityQingdao266071P.R.China Leibniz Institute for Catalysis e.V. Albert-Einstein-Strasse 29aRostock18059Germany School of Materials Science and Engineering Ocean University of ChinaQingdao266100P.R.China Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) SUSTech-Kyoto University Advanced Energy Materials Joint Innovation Laboratory(SKAEM-JIL)Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of GuangdongDepartment of Chemistry and Department of Materials Science and EngineeringSouthern University of Science and Technology(SUSTech)Shenzhen518055P.R.China

PtCo nanoalloys(NAs)deposited on carbon black are emerging as robust electrocatalysts for addressing the sluggish kinetic issue of oxygen reduction reaction(ORR).However,developing a simple and low-cost method to synthesize PtCo/C with excellent performance is still a great *** this work,a one-pot method was used to successfully obtain the PtCo NAs on commercial carbon supports of acetylene black and Ketjenblack ECP600JD,*** with those grown on Ketjenblack ECP600JD,the PtCo NAs grown on acetylene black exhibited higher electrochemical surface area(ECSA)and mass activity(MA),which may be attributed to the different particle sizes of PtCo NAs,distinct hydrophilicity,electroconductivity and charge distribution between the carbon supports and PtCo *** study provides valuable insights into the optimal design of carbon-supported ORR electrocatalysts with exceptional activity and durability.

关键词： Oxygen reduction reaction PtCo nanoalloy Carbon-supported nanostructure Acetylene black

Achieving strength–ductility synergy in novel paramagnetic Fe-based medium-entropy alloys through deep cryogenic deformation

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Rare Metals 2024年第9期43卷 4493-4507页

作者： Hu-Wen Ma Yan-chun Zhao li Feng Tian-Zeng liu Zhi-qi Yu Bo Jin Wang-chun Duan Peter K.liaw Dong Ma State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of Technology Wenzhou Pump and Valve Engineering Research Institute Lanzhou University of Technology Iron and Steel Research Institute Jiuquan Iron and Steel Corporation Lanzhou Resources and Environment Voc-Tech University Department of Materials Science and Engineering The University of Tennessee Neutron Science Center Songshan Lake Materials Laboratory

Cryogenic pre-deformation treatment has been widely used to effectively improve the comprehensive mechanical properties of steels and novel metals. However,the dislocation evolution and phase transformation induced by different degrees of deep cryogenic deformation are not yet fully elucidated. In this study, the effects of multiple cryogenic pre-treatments on the mechanical properties and deformation mechanisms of a paramagnetic Fe63.3Mn14-Si9.1Cr9.8C3.8medium-entropy alloy（MEA） were investigated, leading to the discovery of a pretreated MEA that exhibits exceptional mechanical properties, including a fracture strength of 3.0 GPa, plastic strain of 26.1% and work-hardening index of 0.57. In addition, X-ray diffraction（XRD） and transmission electron microscopy（TEM）analyses revealed that multiple cryogenic pre-deformation treatments significantly increased the dislocation density of the MEA(from 9 × 1015to 4 × 1016m-2after three pretreatments), along with a transition in the dislocation type from predominantly edge dislocations to mixed dislocations（including screw-and edge-type dislocations）. Notably, this pretreated MEA retained its paramagnetic properties（μrlity enhancement of the MEA.

关键词： Deep cryogenic transformation Dislocation evolution Iron-based medium-entropy alloys Phase transformation Stacking fault energy

Transcriptome Analysis of Heterosis in Survival in the Hybrid Progenies of‘Haida No.1’and Orange-Shelled lines of the Pacific Oyster Crassostrea gigas

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Journal of Ocean University of China 2024年第1期23卷 199-208页

作者： YANG Hang li qi Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China

Heterosis has been exploited to enhance the yield and adaptability in various shellfish species;however,the molecular basis of it remains *** Pacific oyster Crassostrea gigas is one of the most economically important aquaculture species,and its productive traits can be improved by ***,an intraspecific cross between orange shell(O,10th generation)and‘Haida No.1’(H,13th generation)of *** was performed to assess the heterosis of survival *** rates of hybrid family(OH)and inbred families(HH and OO)were compared at larval stage,and eyed-pediveliger larvae of three families were subjected to transcriptome *** analysis results of best-parent heterosis and mid-parent heterosis showed that the hybrid family exhi-bited a high heterosis in survival relative to the parental *** OH-M(OH ***)and OH-P(OH ***)had 425 and 512 dif-ferentially expressed genes(DEGs),*** enrichment analysis of these DEGs revealed that the significantly enrich-ed genes function in virion binding,C-type lectin receptor signaling pathway,cellular defense response and other immune-related pro-cesses,which involves perlucin-like protein,CD209 antigen-like protein,ZNFX1,caspase-3 and acan *** differentially ex-pressed genes in OH-M and OH-P,together with the immune-related processes mentioned above may play an important role in the larval survival of *** addition,three genes(CYP450,fucolectin and perlucin-like)are associated with the orange shell and low survival of maternal oyster *** findings provide support for the application of hybrid with superior survival and will facilitate the understanding of heterosis formation in the Pacific oyster.

关键词： Crassostrea gigas survival rate heterosis transcriptome

Simulation study on the security of consensus algorithms in DAG-based distributed ledger

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Frontiers of Computer Science 2024年第3期18卷 171-182页

作者： Shuzhe li Hongwei XU qiong li qi HAN Faculty of Computing Harbin Institute of TechnologyHarbin 150001China

Due to the advantages of high volume of transactions and low resource consumption,Directed Acyclic Graph(DAG)-based Distributed Ledger Technology(DLT)has been considered a possible next-generation alternative to ***,the security of the DAG-based system has yet to be comprehensively *** at verifying and evaluating the security of DAG-based DLT,we develop a Multi-Agent based IOTA Simulation platform called *** MAIOTASim,we model honest and malicious nodes and simulate the configurable network environment,including network topology and *** double-spending attack is a particular security issue related to *** perform the security verification of the consensus algorithms under multiple double-spending attack *** simulations show that the consensus algorithms can resist the parasite chain attack and partially resist the splitting attack,but they are ineffective under the large weight *** take the cumulative weight difference of transactions as the evaluation criterion and analyze the effect of different consensus algorithms with parameters under each attack ***,MAIOTASim enables users to perform largescale simulations with multiple nodes and tens of thousands of transactions more efficiently than state-of-the-art ones.

关键词： distributed ledger IOTA Multi-Agent system simulation