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Spatiotemporal Pattern of Cultivated Land Pressure and Its Influencing Factors in the Huaihai Economic Zone, China

Chinese Geographical Science 2023年第2期33卷 287-303页

作者： LI Yi FANG Bin LI Yurui feng weilun YIN Xu School of Geography Nanjing Normal UniversityNanjing 210023China Research Center of New Urbanization and Land Problem Nanjing Normal UniversityNanjing 210023China Jiangsu Provincial Geographic Information Resources Development and Utilization Cooperative Innovation Center Nanjing 210023China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101China School of Geographic Science Hebei Normal UniversityShijiazhuang 050024China

Cultivated land pressure represents a direct reflection of grain security. Existing relevant studies rarely approached the spatiotemporal pattern of cultivated land pressure or the spatial heterogeneity of its influencing factors from the level of economic *** the Huaihai Economic Zone(HEZ), China for case analysis, this study investigated the spatiotemporal pattern of cultivated land pressure in diverse periods from 2000 to 2018 based on a modified cultivated land pressure index and spatial correlation models. On this basis, it explored the influencing factors of the spatial differentiation of cultivated land pressure in the late stage of the study using geographical detector as well as multi-scale geographically weighted regression model. The results indicated that: 1) in the study period, the global cultivated land pressure index of the study area decreased gradually, but cultivated land pressure increased locally in a significant way, especially in the central and southern Shandong Province;2) the spatial pattern of cultivated land pressure manifested global clustering features. Hot and secondary-hot spots presented a narrowing and clustering trend, whereas cold and secondary-cold spots manifested a spreading and clustering trend;3) average slope, the proportion of non-grain crops, population urbanization rate, and multiple cropping index have significant effects on the spatial differentiation of cultivated land pressure. The former three factors were positively correlated with cultivated land pressure, and the last factor was negatively correlated with cultivated land pressure;and 4) the amount of cultivated land has increased in the central and southern Shandong Province through land consolidation which, nonetheless, failed to improve the grain production. In regards to major grain producing areas similar to the HEZ in China, the authors suggest that great importance should be given to the balance of the quality and quantity of cultivated land, the op

关键词： cultivated land pressure spatiotemporal pattern influencing factors Huaihai Economic Zone China

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现代农业地理工程与农业高质量发展——以黄土丘陵沟壑区为例

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地理学报 2020年第10期75卷 2029-2046页

作者：刘彦随冯巍仑李裕瑞中国科学院地理科学与资源研究所中国科学院区域可持续发展分析与模拟重点实验室北京100101 中国科学院大学北京100049

农业地理学是农业科学与地理科学的交叉学科,农业地理工程是地理学与工程学交叉研究在现代农业与乡村领域的进一步深化和系统应用。随着现代农业科学技术和人地系统科学的创新发展,区域农业基础建设的科技需求日益旺盛,农业地理工程试... 详细信息

农业地理学是农业科学与地理科学的交叉学科,农业地理工程是地理学与工程学交叉研究在现代农业与乡村领域的进一步深化和系统应用。随着现代农业科学技术和人地系统科学的创新发展,区域农业基础建设的科技需求日益旺盛,农业地理工程试验成为农业工程技术研发和农田系统管理的重要任务。本文阐述了农业地理工程的科学内涵、试验原理与技术方法,并以黄土丘陵沟壑区为例开展了地理工程试验研究和农业高质量发展对策探讨。结果表明:①农业地理工程试验主要包括针对特定区域地理环境和农业发展问题的水土配置、土层复配、大田试验、生态防护、地理空间分析与监测,旨在探明区域高标准农田建设、健康农业生态系统营造的水土气生资源要素耦合规律,建立可持续土地利用系统与多功能农业经营模式。②农业生态系统试验主要包括沟道边坡防护方式、健康农田系统结构、作物与土壤匹配关系、耕地投入产出经济分析,通过开展土地改良、作物优选交互试验和田间试种,揭示新造地"作土关系"耦合机理与优化调控途径。③作土关系优化调控是工程试验设计的主要内容,包括气候-作物优选、土体结构改良、地形-作物优选、土壤质量改良、土壤-作物优选、效益-作物优选6个阶段。④农业地理工程技术应用的核心任务是深化贯通综合研究、揭示微观耦合机理、建立工程试验范式,其应用路径主要体现在时间维、空间维与逻辑维三个维度。新时期农业地理工程试验与示范应用,有利于丰富农业地理学前沿理论与方法论,对于推进地理工程化研究和服务农业农村高质量发展决策具有重要意义。

关键词：农业地理学现代地理工程土地整治工程农田系统管理高质量发展黄土丘陵沟壑区

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面向黄土高原耕地高效利用的两季种植模式可行性分析

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Journal of Geographical Sciences 2023年第6期33卷 1271-1286页

作者：冯巍仑刘彦随李裕瑞陈宗峰 Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling CASBeijing 100101China

Cropping systems worldwide have been affected by the current trend in global warming and the optimization of cropping systems is an important area of research in the transition of agricultural land. The Loess Plateau is a typical ecologically fragile region with the most serious soil erosion in China. We carried out a field experiment in Yan’an city on the Loess Plateau to explore the effect of sowing date on crop growth and yield. We then analyzed the feasibility of a double-cropping system by considering climatic adaptability, ecological suitability and economic viability. Our results showed that different sowing dates resulted in significant differences in crop growth and that appropriate early sowing can result in higher crop yields for early maturing varieties. We showed that double-cropping systems of sweet maize(Zea mays)–forage rape and feed maize–forage rape are feasible on the Loess Plateau. We discuss the implications for the efficient use of farmland, which is important in guiding agricultural supply-side reform and the development of modern agricultural management.

关键词： double-cropping systems sowing date maize agricultural land use feasibility analysis Loess Plateau

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基于微观视角的农村转型发展评价及对策探析——以河南省获嘉县楼村为例

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地域研究与开发 2018年第2期37卷 133-137页

作者：冯巍仑李裕瑞刘彦随北京师范大学地理科学学部北京100875 中国科学院地理科学与资源研究所北京100101

在城乡一体化、新型城镇化背景下,加快统筹城乡发展、持续推进农村发展转型具有重大意义。基于微观视角,以河南省获嘉县楼村为例,通过构建平原农区农村发展评价指标体系,简述了研究区农村建设转型的发展历程,探讨了新型农村建设的内生... 详细信息

在城乡一体化、新型城镇化背景下,加快统筹城乡发展、持续推进农村发展转型具有重大意义。基于微观视角,以河南省获嘉县楼村为例,通过构建平原农区农村发展评价指标体系,简述了研究区农村建设转型的发展历程,探讨了新型农村建设的内生性和外源性机理,分析了近年来工农业、生态环境及农民生活等方面的"乡村病"问题,进一步利用农村转型发展领域的相关理论和结合新时期各地的发展实践,提出了研究区推进农村转型发展、破解新农村建设现实难题的对策建议。

关键词：农村转型发展评价对策获嘉县楼村

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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

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基于扫描电镜解析毛乌素沙地砒砂岩与沙复配成土的微观结构特征

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应用基础与工程科学学报 2019年第4期37卷 707-719页

作者：李裕瑞范朋灿曹智冯巍仑陈宗峰王欢元刘彦随中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049 自然资源部退化及未利用土地整治工程重点实验室北京100101 北京师范大学地理科学学部北京100875 陕西省土地工程建设集团有限责任公司陕西西安710075

砒砂岩与沙复配成土造田与生态建设为毛乌素沙地综合治理提供了新途径,但其微观结构与机理研究较为薄弱.本文利用扫描电镜获得风沙土、砒砂岩、复配土及农田土壤的微观图像,定性揭示其表观差异,并综合运用ImageJ、Photoshop、Nano Measu... 详细信息

砒砂岩与沙复配成土造田与生态建设为毛乌素沙地综合治理提供了新途径,但其微观结构与机理研究较为薄弱.本文利用扫描电镜获得风沙土、砒砂岩、复配土及农田土壤的微观图像,定性揭示其表观差异,并综合运用ImageJ、Photoshop、Nano Measurer等图像处理软件定量刻画不同类型土体的孔隙特征、粒级特征和团聚特征.研究表明:①在微观结构上,复配土兼具砒砂岩与风沙土的部分差别化特性;②复配土平均孔隙占有率达32%,较致密的砒砂岩有所改善;③复配土中0~0.05mm土粒占比由风沙土中的3%提升到41%,粒径组成明显优化;④平均每幅电镜图像中复配土团聚体数量达6.67个,尽管与农田土相比仍有差距,但已具备良性发育的基础;⑤复配土与农田土微观结构趋于相似,但功能特性仍略有差距,作物单产仍略低于当地高产田平均水平.本研究建立的技术方法可以较好地定量刻画土壤微观结构特征,对快速直观地判断、调控与管理土壤状况有积极作用.

关键词：扫描电镜砒砂岩风沙土复配土微观结构

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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

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The Hilbert expansion of the Boltzmann equation in the incompressible Euler level in a channel

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Science China Mathematics 2025年第1期68卷 39-88页

作者： Feimin Huang Weiqiang Wang Yong Wang feng Xiao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and StatisticsHunan Normal University

The study of the hydrodynamic limit of the Boltzmann equation with physical boundary is a challenging problem due to the appearance of the viscous and Knudsen boundary *** this paper,the hydrodynamic limit from the Boltzmann equation with the specular reflection boundary condition to the incompressible Euler equations in a channel is *** on the multi-scaled Hilbert expansion,the equations with boundary conditions and compatibility conditions for interior solutions,and viscous and Knudsen boundary layers are derived under different scaling,***,some uniform estimates for the interior solutions,and viscous and Knudsen boundary layers are *** the help of the L2-L∞framework and the uniform estimates obtained above,the solutions to the Boltzmann equation are constructed by the truncated Hilbert expansion with multiscales,and hence the hydrodynamic limit in the incompressible Euler level is justified.

关键词： Boltzmann equation incompressible Euler equations hydrodynamic limit Hilbert expansion specular reflection boundary condition viscous boundary layer Knudsen boundary layer

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Optimizing battery deployment: Aging trajectory prediction enabling homogenous performance grouping

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Journal of Energy Chemistry 2025年第1期100卷 565-577页

作者： Shuquan Wang feng Gao Zhan Ma Hao Tian Yusen Zhang School of Control Science and Engineering Shandong University Key Lab of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University

As battery deployments in electric vehicles and energy storage systems grow, ensuring homogeneous performance across units is crucial. We propose a multi-derivative imaging fusion(MDIF) model, employing advanced imaging and machine learning to predict battery aging trajectories from minimal initial data, thus facilitating effective performance grouping before deployment. Utilizing a derivative strategy and Gramian Angular Difference Field for dimensional enhancement, the MDIF model uncovers subtle predictive features from discharge curve data after only ten cycles. The architecture includes a parallel convolutional neural network with lateral connections to enhance feature integration and *** on a self-developed dataset, the model achieves an average root-mean-square error of 0.047 Ah and an average mean absolute percentage error of 1.60%, demonstrating high precision and *** robustness is further validated through transfer learning on two publicly available datasets, adapting with minimal retraining. This approach significantly reduces the testing cycles required, lowering both time and costs associated with battery testing. By enabling precise battery behavior predictions with limited data, the MDIF model optimizes battery utilization and deployment strategies, enhancing system efficiency and sustainability.

关键词： Lithium-ion battery Battery prognostics Fusion model Convolutional neural network Transfer learning

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Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-feng Yang Hai-feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

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