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Prediction for permeability index of blast furnace based on VMD-PSO-BP model

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Journal of Iron and Steel Research(International) 2024年第3期31卷 573-583页

作者： Xiao-jie liu Yu-jie Zhang Xin Li Zhi-feng Zhang Hong-yang Li Ran liu Shu-jun Chen School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Chengde Branch HBIS Group Co.Ltd.Chengde 067000HebeiChina

The permeability index is one of the important production indicators to monitor the operation of blast furnace.It is crucial to grasp the trends of changes in the new permeability index in time.For the complex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode decomposition-particle swarm optimization-back propagation)method was proposed.Firstly,the key factors that affect the permeability index of blast furnace were studied from multiple perspectives.Then,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each sub-mode.Finally,the prediction results of each sub-mode were summed to obtain the final one.The results show that the composite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.

关键词： Big data-Blast furnace Air permeability Variational mode decomposition Particle swarm optimization Back propagation Model prediction

Rapid report of source parameters of 2023 M6.2 Jishishan,Gansu earthquake sequence

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Earth and Planetary Physics 2024年第2期8卷 436-443页

作者： ZhiGao Yang jie liu YingYing Zhang Wen Yang XueMei Zhang China Earthquake Networks Center Beijing 100045China

The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake disasters.It was located in the northern part of the north−south seismic zone,which is a key area for earthquake monitoring in China.The newly built dense strong motion stations in this area provide unprecedented conditions for high-precision earthquake relocation,especially the earthquake focal depth.This paper uses the newly built strong motion and traditional broadband seismic networks to relocate the source locations of the M3.0 and above aftershocks and to invert their focal mechanisms.The horizontal error of earthquake location is estimated to be 0.5−1 km,and the vertical error is 1−2 km.The focal depth range of aftershocks is 9.6−14.6 km,distributed in a 12-km-long strip with SSE direction.Aftershocks in the south are more concentrated horizontally and vertically,while aftershocks in the north are more scattered.The focal mechanisms of the main shock and aftershocks are relatively consistent,and the P-axis orientation is consistent with the regional strain direction.There is a seismic blank area of M3.0 and above,about 3−5 km between the main shock and aftershocks.It is suggested that the energy released by the main shock rupture is concentrated in this area.Based on the earthquake location and focal mechanism of the main shock,it is inferred that the Northern Lajishan fault zone is the seismogenic structure of the main shock,and the main shock did not occur on the main fault,but on a secondary fault.The initial rupture depth and centroid depth of the main shock were 12.8 and 14.0 km,respectively.The source rupture depth may not be the main reason for the severe earthquake disaster.

关键词： Jishishan earthquake earthquake relocation focal mechanism strong motion data

High-Superelasticity NiTi Shape Memory Alloy by Directed Energy Deposition-Arc and Solution Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 132-144页

作者： Junyi Ma Lin Yu Qing Yang jie liu Lei Yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan430074China

Directed energy deposition-arc(DED-Arc)technology has the advantages of simple equipment,low manufacturing cost and high deposition rate,while the use of DED-Arc has problems of microstructure inhomogeneity,position dependence of macroscopic mechanical properties and anisotropy.Therefore,it is necessary to carry out a subsequent heat treatment to improve its microstructure uniformity,mechanical properties and superelasticity.In this investigation,the DED-Arc 15-layer NiTi alloy thin-walled parts with the solution treatment at different process parameters were studied to analyze the effects of solution heat treatment on microstructure,phase composition,phase transformation,microhardness,tensile and superelasticity.The temperature range of solution treatment is 800-1050℃,and the treatment time range is 1-5.5 h.The results show that after solution treatment at 800℃/1 h,the content of precipitated phase decreases,the grain is refined,the microhardness increases,and the mechanical properties in the 0°direction are improved.The strain recovery rate after 10 tensile cycles has increased from 37.13%(as-built)to 49.25%(solid solution treatment).This research provides an effective post treatment method for high-performance DED-Arc NiTi shape memory alloys.

关键词： Directed energy deposition-arc(DED-Arc) Cold metal transfer(CMT) NiTi shape memory alloys Microstructure Phase transformation Solution heat treatment

Synergism of solar-driven interfacial evaporation and photo-Fenton Cr(Ⅵ) reduction by sustainable Bi-MOF-based evaporator from waste polyester

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Journal of Energy Chemistry 2024年第7期94卷 527-540页

作者： Zifen Fan jie liu Huajian liu Lijie liu Yan She Xueying Wen Huiyue Wang Guixin Hu Ran Niu Jiang Gong Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSemiconductor Chemistry CenterSchool of Chemistry and Chemical EngineeringHuazhong University of Science andTechnologyWuhan430074HubeiChina

The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is fuzzy.Herein,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater production.Firstly,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic property.Attributing to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of irradiation.When integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced catalysts.In the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.

关键词： Interfacial solar steam generation Cr(VI)reduction Photo-Fenton reaction Metal-organic framework Waste plastic upcycling

Flow characterization of macroporous W-4.8 vol.%ZrO2 alloy during hot deformation with improved constitutive equation and processing maps

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Tungsten 2024年第3期6卷 610-620页

作者： Jia-Hao Ye liu-jie Xu Ji-Kang Hu School of Materials Science and Engineering Henan University of Science and Technology National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and Technology

In this work,isothermal compression experiments of macroporous W-4.8 vol.%ZrO2（W-4.8ZrO2） at 1300-1600℃ and strain rate of 0.005-1 s-1were carried out on a Gleeble-1500D thermo-mechanical simulator.The dynamic recovery of W-4.8ZrO2is the main "softening" mechanism.On the basis of Arrhenius model,the initial constitutive equation is established by exploring the influence of temperature,strain rate and rheological stress.Based on Arrhenius model,the relationship between flow stress,strain rate and deformation temperature is established.Considering the influence of strain,the improved constitutive equation and the law of material constant changing with the strain are obtained.After that,the hot processing maps were drawn on the basis of the dynamic material model,which is used to analyze the instability mechanism of the W-4.8ZrO2,and determine the appropriate hot working process parameters(temperature:1350-1450℃,strain rate:0.1-1 s-1).

关键词： Tungsten alloy Flow characteristics Constitutive equation Hot processing maps

An Integral Method for Solving Dynamic Equations with Fluid–Solid Coupling

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Acta Mechanica Solida Sinica 2024年第1期37卷 99-108页

作者： Xin Zhang jie liu Pu Xue Shuowen Yan Yahao Xu M.S.Zahran School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new methodology is presented to mainly solve the fluid–solid interaction(FSI)equation.This methodology combines the advantages of the Newmark precise integral method(NPIM)and the dual neural network(DNN)method.The NPIM is employed to modify the exponential matrix and loading vector based on the DNN integral method.This involves incorporating the basic assumption of the Newmark-βmethod into the dynamic equation and eliminating the acceleration term from the dynamic equilibrium equation.As a result,the equation is reduced to a first-order linear equation system.Subsequently,the PIM is applied to integrate the system step by step within the NPIM.The DNN method is adopted to solve the inhomogeneous term through fitting the integrand and the original function with a pair of neural networks,and the integral term is solved using the Newton–Leibniz formula.Numerical examples demonstrate that the proposed methodology significantly improves computing efficiency and provides sufficient precision compared to the DNN method.This is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newmark precise integral method(NPIM) Dual neural networks(DNN) Fluid-solid interaction(FSI) Dynamic time-history analysis Blast loading

The algebra of symmetric tensors on smooth projective varieties In Memory of Professor Gang Xiao

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Science China Mathematics 2024年

作者： Arnaud Beauville jie liu CNRS Laboratoire J.-A.Dieudonné Université C?te d'Azur Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, we discuss the C-algebra H0(X, S~·TX) for a smooth complex projective variety X.We compute it in some simple examples, and give a sharp bound on its Krull dimension. Then we propose a conjectural chara...

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High-performance Si/VO_(2)-nanorod heterojunction photodetector based on photothermoelectric effect for detecting human radiation

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Rare Metals 2024年第3期43卷 1177-1185页

作者： Fu-Hai Guo Lan-Zhong Hao Wei-Zhuo Yu Si-Qi Li Guan-Chu liu Jing-Yi Hao Yun-jie liu College of Science China University of PetroleumQingdao266580China School of Materials Science and Engineering China University of PetroleumQingdao266580China

As a typical candidate of optoelectronic materials,vanadium dioxide(VO_(2))has wide applications in photodetectors(PDs),but is still challenging in largely enhancing the photodetecting performance for low-power human radiation.Herein,high-performance Si/VO_(2)nanorods(NRs)heterojunction PDs based on the photothermoelectric(PTE)effect are presented.The uniform VO_(2)-NRs array films were deposited on Si by using magnetron sputtering technique,and a Si/VO_(2)heterojunctions were fabricated.The device exhibits a four-stage photoresponse and broadband photoresponse from ultraviolet to long-wavelength infrared.Benefited from the unique nanorods structure and the strong PTE effect,the fabricated device exhibits a large enhancement of the photodetecting performance,showing an ultrahigh photodetectivity of 1.6×10^(13)Jones and ultrafast response rates with a risingedge time of~65.0μs,three orders of magnitude higher than other VO_(2)-based devices.Furthermore,the device exhibits unique abilities to detect human radiation even when the human fingers are far away from the device surface up to 10.0 cm.Additionally,the fabricated Si/VO_(2)devices can also be applied as breath sensors to distinguish different breathing patterns.These results supply an effective route to design high-performance photodetectors toward detecting human thermal radiation and respiration.

关键词： Vanadium dioxide Heterojunction Photodetector Photothermoelectric Human radiation and respiration sensing

Chloroplast immunity: A cornerstone of plant defense

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Molecular Plant 2024年第5期17卷 686-688页

作者： jie liu Pan Gong Ruobin Lu Rosa Lozano-Duran Xueping Zhou Fangfang Li State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory of Rice Biology Institute of BiotechnologyZhejiang UniversityHangzhouZhejiang 310058China Department of Plant Biochemistry Centre for Plant Molecular Biology(ZMBP)Eberhard Karls UniversityTubingen 72076Germany

Increasing evidence supports the notion that pattern-recognition-receptor-mediated immunity goes beyond plasma membrane-to-nucleus signaling.With the findings of the pathways linking plasma membrane and chloroplasts and the functions of stromules and perinuclear chloroplast clustering(PCC)in plant defense,chloroplast immunity has emerged as a cornerstone of plant defense and a target of plant pathogens.

关键词： plant immunity corners