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Breaking the activity limitation of iridium single-atom catalyst in hydrogenation of quinoline with synergistic nanoparticles catalysis

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Nano Research 2022年第6期15卷 5024-5031页

作者： Qikai Shen hongqiang Jin Peipei Li Xiaohu yu Lirong Zheng Weiguo Song Changyan Cao Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesCAS Key Laboratory of Molecular Nanostructure and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Institute of Theoretical and Computational Chemistry Shaanxi Key Laboratory of CatalysisSchool of Chemical&Environment SciencesShaanxi University of TechnologyHanzhong 723000China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Single-atom catalysts(SACs)with the advantages of homogeneous and heterogeneous catalysts have become a hot-spot in catalysis ***,for lack of metal–metal bond in SACs,H_(2)has to go through heterolytic dissociation pathway,which has higher barrier than homolytic dissociation pathway,and thus limits the hydrogenation activity of ***,we propose and demonstrate through constructing synergistic iridium single atoms and nanoparticles co-existed catalyst(denoted as Ir_(1+NPs)/CMK)to boost the catalytic activity of quinoline *** experimental and density functional theory calculation results confirm that Ir_(1)single sites activate quinoline,while Ir nanoparticles boost hydrogen dissociation.H atoms generated at Ir nanoparticles migrate to the quinoline bounded Ir_(1)single sites to complete *** Ir_(1+NPs)/CMK catalyst exhibits much higher reactivity with turnover frequency of 7,800 h^(−1)than those counterpart Ir_(1)/CMK and IrNPs/CMK catalysts,and is 20,000 times higher activity of commercial Ir/C benchmark catalyst for hydrogenation of quinoline under the same reaction *** synergistic catalysis strategy between single atoms and nanoparticles provides a solution to further improve the performance of SACs for hydrogenation.

关键词： heterogeneous catalysis single atom synergistic quinoline hydrogenation

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao yu-Gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Three-dimensional oxygen-doped porous graphene:Sodium chloridetemplate preparation,structural characterization and supercapacitor performances

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Chinese Journal of Chemical Engineering 2021年第12期34卷 304-314页

作者： Zesheng Li Bolin Li Lijun Du Weiliang Wang Xichun Liao Huiqing yu Changlin yu hongqiang Wang Qingyu Li College of Chemistry Guangdong University of Petrochemical TechnologyMaoming 525000China Guangxi Key Laboratory of Low Carbon Energy Materials Guangxi Normal UniversityGuilin 541004China

Supercapacitor is a new type of energy storage device,which has the advantages of high-power property and long cycle *** this study,three-dimensional graphene(3 D-GN)with oxygen doping and porous structure was prepared from graphene oxide(GO)by an inexpensive sodium chloride(NaCl)template,as a promising electrode material for the *** structure,morphology,specific surface area,pore size,of the sample were characterized by XRD,SEM,TEM and BET *** electrochemical performances of the sample were tested by CV and CDC *** 3 D-GE product is a threedimensional nano material with hierarchical porous structures,its specific surface area is much larger than that of routine stacked graphene(GN),and it contains a large number of mesoporous and macropores,a small amount of *** capacitance characteristics of the 3 D-GN electrode material are excellent,showing high specific capacitance(173.5 F·g^(-1)at 1 A·g^(-1)),good rate performance(109.2 F·g^(-1)at 8 A·g^(-1))and long cycle life(88%capacitance retention after 10,000 cycles at 8 A·g^(-1))

关键词： 3-D porous graphene Template preparation Sodium chloride Supercapacitor

Molecular-scale co-assembly membranes derived from keplerate cluster:carbonic anhydrase-mimicking nanocapsules for enhanced CO_(2)/N_(2)separation

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Science China Chemistry 2024年第10期67卷 3271-3282页

作者： Wan-Lei Zhao hongqiang Li Ruoxuan Zheng Yixin Yang Wei Chen yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou 324000China

The development of CO_(2)separation membranes with high permeability and high selectivity,as well as ultra-thin selective layers,has always been ***,a molecular-scaled co-assembly strategy is employed to fabricate the Pebax-Mo_(132)(Pebax=polyether-block-amide copolymer;Mo_(132)=(NH_(4))_(42)[Mo_(72)^(Ⅵ)Mo_(60)^(Ⅴ)O_(372)(CH_(3)COO)_(30)(H_(2)O)_(72)])*** optimal selfstanding membrane,Pebax-Mo_(132)-5%,shows a CO_(2)permeability of~384 Barrer and an ultra-high ideal CO_(2)/N_(2)selectivity of~244,outperforming most membranes reported in the *** CO_(2)permeability and ideal CO_(2)/N_(2)selectivity are increased by 70%and 367%,respectively,compared with the pristine Pebax membrane.A thin-film composite membrane prepared by spin-coating technique on a support membrane with gutter layers also exhibits a CO_(2)permeance of 838 GPU and a CO_(2)/N_(2)selectivity of *** excellent performance can be attributed to the following reasons:(1)strong hydrogen bonding interactions between{Mo_(132)}clusters and Pebax confer excellent interfacial compatibility to the mixed matrix membranes;(2)incorporation of hollow{Mo_(132)}clusters into the Pebax molecular chain decreases the crystallinity of Pebax,and thereby accelerates the chain dynamics and increases the free volume of the membrane;(3)in situ diffuse reflectance infrared Fouriertransform spectroscopy demonstrates that the{Mo_(132)}clusters can effectively catalyze the hydration reaction of CO_(2)and promote the transport of CO_(2);(4)furthermore,the 0.35 nm pores of the crown ether-type{Mo_(9)O_(9)}allow the accurate size sieving of CO_(2)(0.33 nm)and N_(2)(0.36 nm)molecules.

关键词： polyoxometalates molecular-scale assembly CO_(2)capture mixed matrix membranes

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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping yu Emily Choi Michael QJiang Ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Two centuries-long records of skeletal calcification in massive Porites colonies from Meiji Reef in the southern South China Sea and its responses to atmospheric CO_2 and seawater temperature

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Science China Earth Sciences 2012年第1期55卷 1-12页

作者： SHI Qi yu KeFu CHEN TianRan ZHANG HuiLing ZHAO MeiXia YAN hongqiang Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Rising atmospheric CO2 and warming of the global climate that have occurred since the industrial revolution are regarded as fatal threats to coral reefs. We analyzed the skeletal calcification rate of 14 massive Porites corals from the Meiji Reef in the southern South China Sea through X-ray photography of coral skeletons. A general pattern of change in coral skeletal calcifi- cation was determined. The change pattern of coral calcification on the Meiji Reef over the past two centuries can be divided into five periods： calcification increase in 1770-1830, 1870-1920, and 1980-2000 and calcification decline in 1830-1870 and 1920-1980. Over the past two centuries, the largest increase in calcification was 4.5%, occurring in 1770-1830, whereas the largest decline in calcification was 6.2%, occurring in 1920-1980. Coral calcification slightly increased in the recent 20 years （1980-2000）. The response relationship of coral calcification to atmospheric CO2 and sea surface temperature （SST） shows that calcification was not correlated with atmospheric CO2 but responded nonlinearly to SST with maxima at ~27.2~C in 1900-2000. On the Meiji Reef, increasing atmospheric CO2 had a negligible effect on coral growth in the past century. How- ever, rising SST improved coral growth in the early and middle 20th century, and restricted coral growth in the recent 20 years.

关键词： skeletal calcification atmospheric C02 SST Porites coral South China Sea

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盾构渣土处置和资源化应用及建议

广东化工 2021年第19期48卷 104-105页

作者：钟仁华邱紫迪余承晔吴岸松蔡红春余洪强湖南鑫恒环境科技有限公司湖南长沙410217 深圳市洪桦环保科技有限公司广东深圳518116

随着城市的发展,地铁等轨道交通的建设,大量的由盾构机施工产生的废弃渣土给城市环境造成了新的问题。如果能将盾构渣土正确地处理并加以资源化再利用,具有明显的经济、社会和生态效益。本文讨论了现行的盾构渣土脱水技术和高效堆填的... 详细信息

随着城市的发展,地铁等轨道交通的建设,大量的由盾构机施工产生的废弃渣土给城市环境造成了新的问题。如果能将盾构渣土正确地处理并加以资源化再利用,具有明显的经济、社会和生态效益。本文讨论了现行的盾构渣土脱水技术和高效堆填的原则以及资源化利用方式,得出了盾构渣土再利用方式单一,以及耗能高的缺陷的结论,并针对如何正确的处置和资源化应用盾构渣土的问题提出了建议。

关键词：盾构渣土脱水资源化环境隧道

Stability and Stabilization of Sampled-Data Based LFC for Power Systems:A Data-Driven Method

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 291-293页

作者： yu-Long Fan Chuan-Ke Zhang Yong He the School of Automation China University of Geosciences the Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems the Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education IEEE

Dear Editor,This letter is concerned with stability analysis and stabilization design for sampled-data based load frequency control(LFC) systems via a data-driven method. By describing the dynamic behavior of LFC systems based on a data-based representation, a stability criterion is derived to obtain the admissible maximum sampling interval(MSI) for a given controller and a design condition of the PI-type controller is further developed to meet the required MSI. Finally, the effectiveness of the proposed methods is verified by a case study.

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