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Two-dimensional porous carbon derived from pollen with enlarged interlayer distance enhanced electrocatalytic oxidation of n-valeraldehyde to octane

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Nano Research 2024年第5期17卷 3455-3461页

作者： Meichun Qin Chaolong Liu Shouhen Xu jianguo Tang Institute of Hybrid Materials National Center of International Joint Research for Hybrid Materials TechnologyNational Base of International Sci.and Tech.Cooperation on Hybrid MaterialsCollege of Materials Science and EngineeringQingdao UniversityQingdao266071China Department of Pharmaceutics School of PharmacyQingdao UniversityQingdao266071China

Electrocatalytic n-valeraldehyde oxidation reaction was an inexpensive and eco-friendly method to control n-valeraldehyde contamination and produce high value-added ***,low-cost and readily available electrocatalysts with high current efficiency were urgently ***,two-dimensional porous carbon derived from pollen with enlarged interlayer distance was built by alkali activation method,applying in electrocatalytic n-valeraldehyde oxidation *** enlarged interlayer distance was verified by X-ray diffraction(XRD)and high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Electrocatalytic experiments consequences showed activated biomass derived carbon possessed a higher electrocatalytic activity and octane selectivity than unactivated *** tests and in situ infrared experiments demonstrated that enlarged interlayer distance was positively correlated with specific surface area of catalysts,large specific surface area provided abundant absorption sites,facilitated the adsorption for n-valeraldehyde,and further promoted the transformation of n-valeraldehyde to *** work also provides a new avenue for creating high-performance electrocatalysts in terms of lattice engineering.

关键词： biomass derived carbon lattice expansion high specific surface area upgrade of n-valeraldehyde

Beyond network centrality: individual-level behavioral traits for predicting information superspreaders in social media

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National Science Review 2024年第7期11卷 148-157页

作者： Fang Zhou Linyuan Lü jianguo Liu Manuel Sebastian Mariani Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of China School of Cyber Science and Technology University of Science and Technology of China Department of Digital Economics Shanghai University of Finance and Economics URPP Social Networks Universit?t Zürich

Understanding the heterogeneous role of individuals in large-scale information spreading is essential to manage online behavior as well as its potential offline consequences. To this end, most existing studies from diverse research domains focus on the disproportionate role played by highly connected ‘hub’ ***, we demonstrate here that information superspreaders in online social media are best understood and predicted by simultaneously considering two individual-level behavioral traits: influence and susceptibility. Specifically, we derive a nonlinear network-based algorithm to quantify individuals' influence and susceptibility from multiple spreading event data. By applying the algorithm to large-scale data from Twitter and Weibo, we demonstrate that individuals' estimated influence and susceptibility scores enable predictions of future superspreaders above and beyond network centrality, and reveal new insights into the network positions of the superspreaders.

关键词： complex networks social networks social media information spreading superspreaders

Adaptive Optimal Output Regulation of Interconnected Singularly Perturbed Systems With Application to Power Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 595-607页

作者： jianguo Zhao Chunyu Yang Weinan gao Linna Zhou Xiaomin Liu the Engineering Research Center of Intelligent Control for Underground Space Ministry of EducationChina University of Mining and TechnologyXuzhou 221116 the School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116 IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China

This article studies the adaptive optimal output regulation problem for a class of interconnected singularly perturbed systems(SPSs) with unknown dynamics based on reinforcement learning(RL).Taking into account the slow and fast characteristics among system states,the interconnected SPS is decomposed into the slow time-scale dynamics and the fast timescale dynamics through singular perturbation *** the fast time-scale dynamics with interconnections,we devise a decentralized optimal control strategy by selecting appropriate weight matrices in the cost *** the slow time-scale dynamics with unknown system parameters,an off-policy RL algorithm with convergence guarantee is given to learn the optimal control strategy in terms of measurement *** combining the slow and fast controllers,we establish the composite decentralized adaptive optimal output regulator,and rigorously analyze the stability and optimality of the closed-loop *** proposed decomposition design not only bypasses the numerical stiffness but also alleviates the *** efficacy of the proposed methodology is validated by a load-frequency control application of a two-area power system.

关键词： Adaptive optimal control decentralized control output regulation reinforcement learning(RL) singularly perturbed systems(SPSs)

Deformation mechanism and hydrocarbon significance of Eocene organic-rich fine-grained soft sediments in the Leijia Region,Liaohe Depression

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Frontiers of Earth Science 2024年第1期18卷 83-97页

作者： Yijie WEN jianguo ZHANg Shu TAO Chenyu CAI School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Strategy Evaluation for Shale gas(Ministry of Land Resources) China University of Geosciences(Beijing)Beijing 100083China School of Foreign Languages China University of Geosciences(Beijing)Beijing 100083China

The deformation structure of soft sediments has always been a research hotspot,which is of great significance for analyzing the tectonic and sedimentary evolution background of a basin,as well as the physical properties of *** studies have reported that a large number of soft sediment deformation structures are developed in the western part of Liaohe *** this study,through core observation and thin section identification,various types of deformation structures are identified in the core samples which are collected from the upper Es4 in the Leijia region,western sag of Liaohe depression,such as liquefied dikes,liquefied breccia,convoluted laminae,annular bedding,synsedimentary faults,vein structures,*** on the characteristics of core structure,single well profile and continuous well profile,combined with the regional background,this study clarifies that the deformation structure of soft sediments in the study area is mainly caused by seismic *** is found that the permeability and porosity of deformation layers in the study area are higher than those of the undeformation layers,which proves that the deformation structure of soft sediments has a good effect on improving the physical properties of reservoirs.

关键词： soft sediment deformation structure Liaohe depression organic-rich fine-grained soft sediments hydrocarbon significance

Explosion resistance performance of reinforced concrete box girder coated with polyurea:Model test and numerical simulation

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Defence Technology（防务技术） 2024年第3期33卷 1-18页

作者： guangpan Zhou Rong wa.g Mingyang wa.g jianguo Ding Yuye Zhang School of Science Nanjing University of Science and TechnologyNanjing 210094JiangsuChina School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina State Key Laboratory of Explosion and Impact and Disaster Prevention and Mitigation Army Engineering University of PLANanjing 210007JiangsuChina

To study the anti-explosion protection effect of polyurea coating on reinforced concrete box girder,two segmental girder specimens were made at a scale of 1:3,numbered as g(without polyurea coating)and PCg(with polyurea coating).The failure characteristics and dynamic responses of the specimens were compared through conducting explosion *** reliability of the numerical simulation using LS-DYNA software was verified by the test *** effects of different scaled distances,reinforcement ratios,concrete strengths,coating thicknesses and ranges of polyurea were *** results show that the polyurea coating can effectively enhance the anti-explosion performance of the *** top plate of middle chamber in specimen g forms an elliptical penetrating hole,while that in specimen PCg only shows a very slight local *** peak vertical displacement and residual displacement of PCg decrease by 74.8% and 73.7%,respectively,compared with those of specimen *** the TNT explosion with small equivalent,the polyurea coating has a more significant protective effect on reducing the size of *** the increase of TNT equivalent,the protective effect of polyurea on reducing girder displacement becomes more *** optimal reinforcement ratio,concrete strength,thickness and range of polyurea coating were also drawn.

关键词： Explosive load Explosion resistance performance Model test Polyurea Concrete box girder Numerical simulation

Comparative analysis of frictional behavior and mechanism of molybdenum ditelluride with different structures

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Friction 2024年第1期12卷 110-119页

作者： Lina ZHANg Xinfeng TAN jianguo JIAO Dan gUO Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have layered structures with excellent tribological *** the energy difference between hexagonal-molybdenum ditelluride(2H-MoTe_(2))and distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2))is very small among the transition metal dichalcogenides(TMDCs),MoTe_(2) becomes one of the most promising candidates for phase *** our experiment,we found that the friction force and friction coefficient(COF)of 2H-MoTe_(2) were an order of magnitude smaller than those of 1T′-MoTe_(2) by the atomic force microscope(AFM)*** friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) was further verified in molecular dynamics(MD)*** density functional theory(DFT)calculations suggest that the friction contrast is related to the difference in sliding energy barrier of the potential energy surface(PES)for a tip sliding across the *** PES obtained from the DFT calculation indicates that the maximum energy barrier and the minimum energy path(MEP)energy barrier of 2H-MoTe_(2) are both smaller than those of 1T′-MoTe_(2),which means that less energy needs to be dissipated during the sliding *** difference in energy barrier of the PES could be ascribed to its larger interlayer spacing and weaker Mo–Te interatomic interactions within the layers of 2H-MoTe_(2) than those of 1T′-MoTe_(2).The obvious friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) not only provides a new non-destructive means to detect the phase transition by the AFM,but also provides a possibility to tune friction by controlling the phase transition,which has the potential to be applied in extreme environments such as space lubrication.

关键词： friction two-dimensional(2D)materials distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2)) hexagonal-molybdenum ditelluride(2H-MoTe_(2)) phase transition

Spectroscopic factors of resonance states with the gamow shell model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 38-45页

作者： Mengran Xie jianguo Li Nicolas Michel Honghui Li Wei Zuo CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

We provide an investigation of the spectroscopic factor of resonance states in A=5-8 nuclei,utilizing the gamow shell model(gSM).Within the gSM,the configuration mixing is taken into account exactly with the shell model framework,and the continuum coupling is addressed via the complex-energy Berggren ensemble,which treats bound,resonance,and non-resonant continuum single-particle states on an equal *** a result,both the configuration mixing and continuum coupling are meticulously considered in the *** first calculate the low-lying states of helium isotopes and isotones with the gSM,and the results are compared with that of ab initio no-core shell model(NCSM)*** results indicate that gSM can reproduce the low-lying resonance states more accurately than the *** this,we delve into the spectroscopic factors of the resonance states as computed through both gSM and NCSM,concurrently conducting systematic calculations of overlap functions pertinent to these resonance ***,the calculated overlap function and spectroscopic factor of6He(01+)■νp3/2→^(7)He(3/2_(1)-)with gSM are compared with the results from ab initio NCSM,variational Monte Carlo,and green’s function Monte Carlo calculations,as well as available experimental *** results assert that wave function asymptotes can only be reproduced in gSM,where resonance and continuum coupling are precisely addressed.

关键词： spectroscopic factor overlap function resonance states continuum coupling isospin symmetry breaking

Beyond skyline and borders: Unraveling the evolution and drivers of tourism green development efficiency in the Beijing-Tianjin-Hebei urban agglomeration, China

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Journal of geographical Sciences 2024年第9期34卷 1761-1796页

作者： HUANg Xingling LIU jianguo College of Tourism and Service Management Nankai UniversityTianjin 300071China Tourism College of Beijing Union University Beijing 100101China Department of City and Regional Planning The University of North Carolina at Chapel HillNC 27599USA

green development is a critical component of sustainable tourism, which prioritizes a comprehensive, ecologically-friendly, and people-oriented approach to development. This study presents a case study of the Beijing–Tianjin–Hebei(BTH) urban agglomeration from 2001 to 2021 to analyze the spatio-temporal evolution characteristics and influencing factors of tourism green development efficiency(TgDE). The study defines the concept of tourism green development and constructs an evaluation system, which is used to explore the internal differences and spatial patterns of TgDE within the urban agglomeration. The methodological approach includes the SBM–Undesirable model, kernel density estimation, Markov chain, and spatial gravity model. The findings indicate that the TgDE in the BTH urban agglomeration is generally favorable, displaying a temporal phase of “rising–declining–rising.” However, the study observes lower TgDE in tourism node cities compared to tourism regional center cities and tourism core hub cities. The non-equilibrium degree of each region indicates significant spatio-temporal evolution patterns and internal differences among the three regions, with a spatially decreasing distribution of “core hub-regional center-node city.” The TgDE in the urban agglomeration experienced an evolutionary trend of “first decreasing and then increasing” with apparent endogenous evolution characteristics. The linkage pattern of green development efficiency in the tourism industry between cities is relatively stable. Furthermore,neighboring cities generally exhibit a higher spatial connectivity strength of green development efficiency in the tourism industry compared to non-neighboring cities. Economic development level, industrial structure, and science and education level are identified as key factors that affect TgDE. However, the study finds that the factors influencing TgDE in tourism core hub cities, tourism regional center cities, and tourism node cities differ somewhat

关键词： BTH urban agglomeration tourism green development efficiency(TgDE) spatio-temporal evolution

Regulating the oxidation state of Pd to enhance the selective hydrogenation for 5-hydroxymethylfurfural

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Chinese Journal of Chemical Engineering 2024年第8期72卷 60-68页

作者： Xin Li Yue Ma Xuning wa.g jianguo Wu Dong Cao Daojian Cheng State Key Laboratory of Organic-Inorganic Composites and College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

The highly selective hydrogenation of 5-hydroxymethylfurfural to 2,5-dihydroxymethylfuran is an important reaction in the field of biomass hydrogenation,because it is a bridge between biomass resources and chemical ***,we precisely constructed carbon nitride supported Pd-based catalysts by a simple impregnation-reduction *** changing the reduction temperature,catalysts with different oxidation state could be precisely ***,the important correlation between the ratio of Pd^(0)/Pd^(2+)and catalytic activity is revealed during the selective hydrogenation of *** Pd/g—C_(3)N_(4)—300 catalyst with a Pd^(0)/Pd^(2+)ratio of 3/2 showed the highest catalytic activity,which could get 96.9%5-hydroxymethylfurfural conversion and 90.3%2,5-dihydroxymethylfuran *** density functional theory calculation revealed that the synergistic effect between Pd0and Pd2+in Pd/g—C_(3)N_(4)—300 system could boost the adsorption of the substrate and the dissociation of *** this work,we highlight the important correlation between metal oxidation state and catalytic activity,which provides valuable insights for the rational design of precious metal catalysts for hydrogenation reactions.

关键词： Pd/g-C_(3)N_(4) Selective hydrogenation 5-hydroxymethylfurfural 2,5-dihydroxymethylfuran Oxidation state