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The P_(5)-saturation Game

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 295-304页

作者： Zhen HE Mei lu School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044China department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

Let F,G and H be three graphs with G■*** call G an F-saturated graph relative to H,if there is no copy of F in G but there is a copy of F in G+e for any e∈E(H)\E(G).The F-saturation game on host graph H consists of two players,named Max and Min,who alternately add edges of H to G such that each chosen edge avoids creating a copy of F in G,and the players continue to choose edges until G becomes F-saturated relative to *** wishes to maximize the length of the game,while Min wishes to minimize the *** sat_(g)(F,H)(***_(g)'(F,H))denote the number of edges chosen when Max(*** Min)starts the game and both players play *** this article,we show that sat_(g)(P_(5),K_(n))=sat_(g)'(P_(5),K_(n))=n+2 for n≥15,and satg(P_(5),K_(m,n)),sat_(g)'(P_(5),K_(m,n))lie in{m+n-[m+2/4];m+n-[m-3/4]}if n≥5/2m and m≥4,respectively.

关键词： saturation number saturation game host graph

An embedded electron current layer observed at the edge of the plasma sheet in the Earth’s magnetotail

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Earth and Planetary Physics 2025年第1期9卷 148-158页

作者： ChenChen Zhan RongSheng Wang QuanMing lu San lu XinMin Li deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetology/CAS Key Laboratory of Geospace Environment/Anhui Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China

The formation of an embedded electron current sheet within the magnetotail plasma sheet has been poorly *** this article,we present an electron current layer detected at the edge of the magnetotail plasma *** ions were demagnetized inside the electron current layer,but the electrons were still frozen in with the magnetic field ***,this decoupling of ions and electrons gave rise to a strong Hall electric field,which could be the reason for the formation of the embedded thin current *** magnetized electrons,the absence of the nongyrotropic electron distribution,and negligible energy dissipation in the layer indicate that magnetic reconnection had not been triggered within the embedded thin current *** highly asymmetric plasma on the two sides of the current layer and low magnetic shear across it could suppress magnetic *** observations indicate that the embedded electric current layer,probably generated by the Hall electric field,even down to electron scale,is not a sufficient condition for magnetic reconnection.

关键词： magnetotail plasma sheet magnetic reconnection

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： jia Zhao Taixi Feng Guimin lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(dPMd) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(dP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained dP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via dPMd simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

In-situ liquid-phase transmission electron microscopy for two-dimensional energy materials

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SCIENCE CHINA-CHEMISTRY 2025年第2期68卷 414-429页

作者： Zhang, junyu Xiao, Liangping lu, Mi Xiamen Univ Technol Sch Mat Sci & Engn Xiamen 361024 Peoples R China Huaqiao Univ Instrumental Anal Ctr Lab & Equipment Management Dept Xiamen 361021 Peoples R China Xiamen Univ Res Inst Biomimet & Soft Matter Jiujiang Res Inst Dept PhysFujian Prov Key Lab Soft Funct Mat Xiamen 361005 Peoples R China

Two-dimensional (2d) materials are vital for the development of advanced materials in the next-generation energy conversion and storage devices. In-situ liquid-phase transmission electron microscopy (LP-TEM) acts as a powerful tool for characterizing the dynamic evolution of materials under work condition in real time and in operando. Herein, this mini-review highlights the considerable advances in the utilization of in-situ LP-TEM for studying the physical and chemical process dynamics of 2d materials, such as their nucleation growth and phase transformation. The electrocatalytic water splitting reactions and CO2 electroreduction of 2d energy materials are highlighted. The underlying electrochemical reaction mechanisms of the 2d electrode materials in rechargeable batteries are discussed and summarized. Finally, the current challenges and perspectives for future research are proposed. This min-review aims to inspire and stimulate further innovation and encourage the broader adoption of LP-TEM in exploring the fascinating dynamics of 2d energy materials.

关键词： two-dimensional (2d) materials liquid-phase transmission electron microscopy electrochemical reaction electrode materials

development of Gravity Theories in the View of TRAPPIST-1e

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Research in Astronomy and Astrophysics 2025年第1期25卷 143-161页

作者： Nan Wang lu-Yao lu Hui-Gen Liu An-dong Chen Tiger lu Ao-Ran Cui jun-Kai Wang Marine Science and Technology College Zhejiang Ocean University Key Laboratory of Modern Astronomy and Astrophysics Ministry of Education Zhoushan Astronomical Society School of Astronomy and Space Science Nanjing University department of Astronomy Yale University Kuang Yaming Honors School Nanjing University School of Physics Nanjing University

Contrary to the solar system, most exoplanet systems detected hitherto are close-in and compact. One typical system is TRAPPIST-1, which has seven nearly co-planar terrestrial planets all within the orbit of Mercury,including three in the habitable zone. To evaluate the differences in developing sophisticated gravity theories from the solar system, we use N-body integrations to simulate ephemeris and reproduce some important astronomy phenomena observed on the potentially habitable planet TRAPPIST-1e. Retrograde motions of other planets last1–2 orders of magnitude shorter than in the solar system, but occur much more frequently. Transit events of all inner planets can be observed steadily. Except for Kepler's first law, which is hard to notice for low eccentricities of planets, the other two laws can then be precisely verified in 102days, because the areas swept by planets vary by?0.01% and the observed semimajor axes and periods result in constants with theoretical and observation accuracies both ?2%. However, the mean motion correlation implies that the Great Inequality is not always apparent between one pair of planets like jupiter and Saturn. Furthermore, general relativity can hardly be discovered because it gives rise to perihelion precession of inner planets only ～0.1% of gravity precession, dozens of times smaller than Mercury. Our results support the possibility of developing part of gravity theories by potential exo-civilizations in compact systems like TRAPPIST-1.

关键词： ephemerides extraterrestrial intelligence gravitation planets and satellites: terrestrial planets

Analyzing carbon emissions and influencing factors in Chengdu-Chongqing urban agglomeration counties

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journal of Environmental Sciences 2025年第5期151卷 640-651页

作者： Zhang Heng lu Wenfu Peng Lindan Zhang Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources(Ministry of Education) Sichuan Normal UniversityChengdu 610068China The Institute of Geography and Resources Science Sichuan Normal UniversityChengdu 610068China

Majority of carbon emissions originate from fossil energy consumption,thus necessitating calculation and monitoring of carbon emissions from energy *** this study,we utilized energy consumption data from Sichuan Province and Chongqing Municipality for the years 2000 to 2019 to estimate their statistical carbon *** then employed nighttime light data to downscale and infer the spatial distribution of carbon emissions at the county level within the Chengdu-Chongqing urban ***,we analyzed the spatial pattern of carbon emissions at the county level using the coefficient of variation and spatial autocorrelation,and we used the Geographically and Temporally Weighted Regression(GTWR)model to analyze the influencing factors of carbon emissions at this *** results of this study are as follows:(1)from 2000 to 2019,the overall carbon emissions in the Chengdu-Chongqing urban agglomeration showed an increasing trend followed by a decrease,with an average annual growth rate of 4.24%.However,in recent years,it has stabilized,and 2012 was the peak year for carbon emissions in the Chengdu-Chongqing urban agglomeration;(2)carbon emissions exhibited significant spatial clustering,with high-high clustering observed in the core urban areas of Chengdu and Chongqing and low-low clustering in the southern counties of the Chengdu-Chongqing urban agglomeration;(3)factors such as GdP,population(Pop),urbanization rate(Ur),and industrialization structure(Ic)all showed a significant influence on carbon emissions;(4)the spatial heterogeneity of each influencing factor was evident.

关键词： Carbon emissions Chengdu-Chongqing urban agglomeration Spatial autocorrelation Geographically and temporally weighted regression

Synthesis of ternary geopolymers using prediction for effective solidification of mercury in tailings

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journal of Environmental Sciences 2025年第1期147卷 392-403页

作者： Xuan lu jinfa Guo Fang Chen Mengkui Tian School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China

This study used steel slag,fly ash,and metakaolin as raw materials(SFM materials)to create silica-alumina-based geopolymers that can solidify Hg^(2+)when activated with sodiumbased water *** experiments began with a triangular lattice point mixing design experiment,and the results were fitted,analyzed,and *** optimum SFM material mass ratio was found to be 70%steel slag,25%fly ash,and 5%*** optimum modulus of the activator was identified by comparing the unconfined compressive strength and solidifying impact on Hg^(2+)of geosynthetics with different *** SFM geopolymer was then applied in the form of potting to cure the granulated mercury *** inclusion of 50%SFM material generated a geosynthetic that reduced mercury transport to the surface soil by roughly 90%.The mercury concentration of herbaceous plant samples was also reduced by 78%.It indicates that the SFM material can effectively attenuate the migration transformation of ***,characterization methods such as XPS and FTIR were used to investigate the mechanism of Hg^(2+)solidification by geopolymers generated by SFM *** possible solidification mechanisms were proposed as alkaline environment-induced mercury precipitation,chemical bonding s,surface adsorption of Hg^(2+)and its precipitates by the geopolymer,and physical encapsulation.

关键词： Mercury Geopolymer Solidification Tailings

dynamical complexity of Anosov systems driven by a quasi-periodic force

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Science China Mathematics 2025年第1期68卷 89-136页

作者： Wen Huang Zeng Lian Kening lu department of Mathematics University of Science and Technology of ChinaHefei 230026China School of Mathematics Sichuan UniversityChengdu 610065China

Consider C^(2)Anosov systems on a compact manifold driven by a quasi-periodic *** study their dynamical complexity on various levels from the perspectives of both path-wise dynamics and stochastic *** that these systems are non-wandering(i.e.,every point in the phase space is nonwandering),we prove a set of results:(1)the existence of abundance of random periodic points;(2)a random Livsic theorem;(3)a random Mañé-Bousch-Conze-Guivarc'h lemma;(4)the existence of strong random ***,a concrete example constructed on a 2-dimensional torus is also given to uncover some interesting phenomena of the systems.

关键词： random Anosov systems Anosov system on bers entropy random periodic orbit random horseshoe cohomological equation random Livsic theorem random Bousch-Mañécohomology lemma

Electronic modulation towards MOFs as template derived CoP via engineered heteroatom defect for a highly effcient overall water splitting

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journal of Energy Chemistry 2025年第2期101卷 598-607页

作者： Meijie ding Zhiqiang Wei dexue Liu Wenhua Zhao Qiang lu Zhiming Li Qingsong Yu Chenggong lu Hua Yang State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of Technology School of Science Lanzhou University of Technology

The reasonable design of material morphology and eco-friendly electrocatalysts are essential to highly efficient water *** is proposed that a promising strategy effectively regulates the electronic structure of the d-orbitals of CoP using cerium doping in this paper,thus significantly improving the intrinsic property and conductivity of CoP for water *** a result,the as-synthesize porous Ce-doped CoP micro-polyhedron composite derived from Ce-ZIF-67 as bifunctional electrocatalytic materials exhibits excellent electrocatalytic performance in both the oxygen evolution reaction（OER） and the hydrogen evolution reaction（HER）,overpotentials of about 152 mV for HER at 10 mA cm-2and about 352 mV for OER at 50 mA cm-2,and especially it shows outstanding long-term ***,an alkaline electrolyzer,using Ce0.04Co0.96P electrocatalyst as both the anode and cathode,delivers a cell voltage value of1.55 V at the current density of 10 mA *** calculation results of the density functional theory（dFT）demonstrate that the introduction of an appropriate amount of Ce into CoP can enhance the conductivity,and can induce the electronic modulation to regulate the selective adsorption of reaction intermediates on catalytic surface and the formation of O*intermediates（CoOOH）,which exhibits an excellent electrocatalytic *** study provides novel insights into the design of an extraordinary performance water-splitting of the multicomponent electrocatalysts.

关键词： Cerium Hydrogen evolution Oxygen evolution Phosphides Water splitting