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Recent progress in the research on magnesium and magnesium alloy foils:A short review

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 842-854页

作者： Qiuyan Shen yongxing ba Peng Zhang Jiangfeng Song Bin Jiang Fusheng Pan national Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China national Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation coefficients,magnetic and electrical conductivities,as well as high theoretical specific ***,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal *** magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to *** methods have been applied to prepare magnesium alloy *** include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating *** of magnesium and magnesium alloy foils during prepa.a.ion,such as edge cracks and brea.a.e,are important factors for ***,the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil prepa.a.ion,defect control,performance cha.a.terization,and application *** advantages and disadvantages of different prepa.a.ion methods and defect(edge cracks and brea.a.e)mechanisms in the prepa.a.ion of foils are identified.

关键词： magnesium alloy foil rolling defect performance application

Physics-based seismic a.a.ysis of ancient wood structure:fault-to-structure simulation

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 727-740页

作者： ba Zhenning Fu Jisai Wang Fangbo Liang Jianwen Zhang Bin Zhang Long State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation (Tianjin University)Tianjin 300350China School of Civil Engineering Tianjin UniversityTianjin 300350China Administrative Office of the Summer Pa.a.e Beijing 100091China School of Architecture Tianjin UniversityTianjin 300072China

based on the domain reduction method,this study employs an SEM-FEM hybrid workflow which integrates the advantages of the spectral element method(SEM)for flexible and highly efficient simulation of seismic wave propa.a.ion in a three-dimensional(3D)regional-scale geophysics model and the finite element method(FEM)for fine simulation of structural response including soil-structure interaction,and performs a physics-based simulation from initial fault rupture on an ancient wood *** verification of the hybrid workflow,a large-scale model of an ancient wood structure in the Beijing area,The Tower of Buddhist Incense,is established and its responses under the 1665 Tongxian earthquake and the 1730 yiheyuan earthquake are *** results from the simulated ground motion and seismic response of the wood structure under the two earthquakes demonstrate that this hybrid workflow can be employed to efficiently provide insight into the relationships between geophysical pa.a.eters and the structural response,and is of great significance toward accurate input for seismic simulation of structures under specific site and fault conditions.

关键词： spectral element method finite element method fault-to-structure simulation physical model domain reduction method

Molecular mechanism of flowering time regulation in Brassica ra.a.similarities and differences with a.a.idopsis

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Horticultural Plant Journal 2024年第3期10卷 615-628页

作者： na Li Rui yang Shuxing Shen Jianjun Zhao State Key Laboratory of North China Crop Improvement and Regulation Key Laboratory of Vegetable Germplasm Innovation and Utilization of HebeiCollaborative Innovation Center of Vegetable Industry in HebeiCollege of HorticultureHebei Agricultural UniversityBaodingHebei 071000China

Properly regulated flowering time is pivotal for successful plant *** floral transition from vegetative growth to reproductive growth is regulated by a complex gene regulatory network that integrates environmental signals and internal conditions to ensure that flowering takes place under favorable *** ra.a.is a diploid Cruciferae species that includes several varieties that are cultivated as vegetable or oil *** time is one of the most important agricultural traits of *** crops because of its influence on yield and *** transition to flowering in *** is regulated by several environmental and developmental cues,which are perceived by several signaling pathways,including the vernalization pathway,the autonomous pathway,the circadian clock,the thermosensory pathway,and gibberellin(GA)*** signals are integrated to control the expression of floral integrators BrFTs and BrSOC1s to regulate *** this review,we summarized current research advances on the molecular mechanisms that govern flowering time regulation in *** and compare this to what is known in a.a.idopsis.

关键词： Flowering time Brassica rapa Vernalization Photoperiod

Spatiotemporal cha.a.teristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020

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Journal of Arid Land 2024年第3期16卷 396-414页

作者： LI Shaoting MU na REN yanjun Thomas GLAUBEN College of Economics and Ma.a.ement Northwest A&F UniversityYangling 712100China Sino-German Center for Agricultural and Food Economics Northwest A&F UniversityYangling 712100China Leibniz Institute of Agricultural Development in Transition Economies(IAMO) Halle 06120Germany

Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally *** study used provincial-level da.a.from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit *** addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based *** results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the *** terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative *** should be noted that these two influencing factors had different impacts on MPAs and ***,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land.

关键词： cultivated land use eco-efficiency(CLUE) slacks-based measure(SBM)model barycentre model standard deviation ellipse(SDE) panel Tobit model carbon emissions nonpoint source pollution

Reactive Transport Process of Earthquake-induced Hydrochemical Changes in Guanding Thermal Spring,Western Sichuan,China

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 241-249页

作者： na Jin JIANG Xue SHI Zheming CHEN yanmei Hubei Key Laboratory of Petroleum Geochemistry and Environment(yangtze University) Wuhan 430100China School of Environmental Studies China University of GeosciencesWuhan 430074China School of Water Resources and Environment China University of GeosciencesBeijing 100083China State Key Laboratory of Water Resource Protection and Utilization in Coal Mining Beijing 100000China

Earthquake-related hydrochemical changes in thermal springs have been widely observed;however,quantitative modeling of the reactive transport process is *** the present study,we apply reactive transport simulation to capture the hydrochemical responses in a thermal spring following the Wenchuan Ms 8.0 and Lushan Ms 7.0 *** first constrain deep reservoir geothermal fluid compositions and temperature by multicomponent geothermometry,and then a reactive geochemical transport model is constructed to reproduce the hydrochemical evolution *** results show that the recharge from the shallow aquifer increases gradually until it reaches a peak because of the permeability enhancement caused by the Lushan earthquake,which may be the mechanism to explain the earthquake-related hydrochemical *** contrast to the postseismic effect of the Wenchuan earthquake,the chemical evolution can be considered as hydrochemical anomalies related to the Lushan *** study proves that the efficient simulation of reactive transport processes is useful for investigating earthquake-related signals in hydrochemical time series.

关键词： earthquake hydrochemical changes reactive geochemical transport model Kangding area

Molecular mechanisms of stress resistance in sorghum: Implications for crop improvement strategies

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Journal of Integrative Agriculture 2024年第3期23卷 741-768页

作者： Hongxiang Zheng yingying Dang Xianmin Diao na Sui Shandong Provincial Key Laboratory of Plant Stress/College of life Sciences Shandong Normal UniversityJinan 250014China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China

Abiotic stresses, such as drought, salt, extreme temperatures, and heavy metal pollution, are the main environmental factors that limit crop growth and yield. Sorghum, a C4 grass plant with high photosynthetic efficiency, can grow in adverse environmental conditions due to its excellent stress resistance cha.a.teristics. Therefore, unraveling the stress-resistance mechanism of sorghum could provide a theoretical basis for developing and cultivating various stress-resistant crops. This understanding could also help to create a conducive environment for using marginal soil in agriculture and ensuring food security. In this review, we discuss the a.a.tation mechanisms of sorghum under drought, salinity, temperature, and soil heavy metal stresses, the specific response to stress, the screening of sorghum-resistant germplasm, and the identification and functional a.a.ysis of the relevant genes and quantitative trait loci(QTL). In addition, we discuss the application potential of different stress-tolerant sorghum germplasms reported to date and emphasize the feasibility and potential use in developing and promoting highly stress-tolerant sorghum in marginal soil.

关键词： abiotic stress C4 plants QTL sorghum stress resistance yield stability

Towards kernelizing the classifier for hyperbolic data

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Frontiers of Computer Science 2024年第1期18卷 17-31页

作者： Meimei yANG Qiao LIU Xinkai SUN na SHI Hui XUE School of Computer Science and Engineering Southeast UniversityNanjing 210096China MOE Key Laboratory of Computer Science and Information Integration(Southeast University) Nanjing 210096China

Da.a.hierarchy,as a hidden property of da.a.structure,exists in a wide range of machine learning applications.A common practice to classify such hierarchical da.a.is first to encode the da.a.in the Euclidean space,and then train a Euclidean ***,such a pa.a.igm leads to a performance drop due to distortion of da.a.embedding in the Euclidean *** relieve this issue,hyperbolic geometry is investigated as an alternative space to encode the hierarchical da.a.for its higher ability to capture the hierarchical *** methods cannot explore the full potential of the hyperbolic geometry,in the sense that such methods define the hyperbolic operations in the tangent plane,causing the distortion of da.a.*** this paper,we develop two novel kernel formulations in the hyperbolic space,with one being positive definite(PD)and another one being indefinite,to solve the classification tasks in hyperbolic *** PD one is defined via mapping the hyperbolic da.a.to the Drury-Arveson(DA)space,which is a special reproducing kernel Hilbert space(RKHS).To further increase the discrimination of the classifier,an indefinite kernel is further defined in the Krein ***,we design a 2-layer nested indefinite kernel which first maps hyperbolic da.a.into the DA spaces,followed by a mapping from the DA spaces to the Krein *** experiments on real-world da.a.ets demonstrate the superiority ofthe proposed kernels.

关键词： da.a.hierarchy hyperbolic cgeometry drury-arveson space krein space

Non-equilibrium kinetic sepa.a.ion of thulium,yttrium and erbium on the surface of freely rising oil droplets

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Journal of Rare Earths 2024年第1期42卷 200-209,I0007页

作者： na Sui Shukai Miao Kaihui Cui Fancheng Meng Kun Huang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious Metals University of Science and Technology BeijingBeijing100083China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China

It is difficult to achieve selective sepa.a.ion and enrichment of different rare earths from high abundance yttrium ores efficiently only dependent on their discrepancy in thermodynamic *** present work suggests a new strategy based on non-equilibrium kinetic sepa.a.ion of Er and Tm on the surface of freely rising oil droplets to control the sepa.a.ion order of *** is revealed that the mutual sepa.a.ion of Er/Tm is significantly promoted with the sepa.a.ion coefficient of 2.89 during the non-equilibrium extraction with the addition of diethylenetriaminepentaacetic acid(DTPA).The extraction sequence of Tm,Er and y can be controlled as Tm>y>Er,thus y can be selectively enriched during the process of sepa.a.ion of Er and Tm,Such a sequence is subject to the controllable dissociation rates of RE(Ⅲ)-DTPA complexes and extraction abilities of P507 with the three RE(Ⅲ)*** dissociation rate is dependent on the stabilities of RE(Ⅲ)-DTPA complexes and follows the sequence ofy(Ⅲ)—DTPA Er>y to Tm>y>Er.

关键词： DTPA Interface interaction Non-equilibrium kinetic sepa.a.ion Rare earths P507

Existence and numerical approximation of a solution to frictional contact problem for electro-elastic materials

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 201-219页

作者： Othman baiz el-Hassan Benkhira Rachid Fakhar University Ibn Zohr Lab.ESERFP of OuarzazateMorocco University Moulay Ismail Faculty of SciencesLaboratory MACSESTMBP 3103Toulal-MeknesMorocco University Sultan Moulay Slimane Laboratory LS2MEPolydisciplary Faculty of Khouribga25000 KhouribgaMorocco

In this paper,a frictional contact problem between an electro-elastic body and an electrically conductive foundation is *** contact is modeled by normal compliance with finite penetration and a version of Coulomb’s law of dry friction in which the coefficient of friction depends on the *** addition,the effects of the electrical conductivity of the foundation are taken into *** model leads to a coupled system of the quasi-variational inequality of the elliptic type for the displacement and the nonlinear variational equation for the electric *** existence of a weak solution is proved by using an abstract result for elliptic variational inequalities and a fixed point ***,a finite element approximation of the problem is *** some regularity conditions,an optimal order error estimate of the approximate solution is ***,a successive iteration technique is used to solve the problem numerically and a convergence result is established.

关键词： piezoelectric material frictional contact variational Inequality fixed point process finite element method error estimation iteration method