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Optimization of Aluminum Alloy Formation Process for Selective Laser Melting Using a Differential Evolution-Framed JAYA Algorithm
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作者 Siwen Xu Hanning Chen +3 位作者 Rui Ni Maowei He Zhaodi Ge Xiaodan Liang 《Computers, Materials & Continua》 2026年第2期420-444,共25页
Selective Laser Melting(SLM),an advanced metal additive manufacturing technology,offers high precision and personalized customization advantages.However,selecting reasonable SLM parameters is challenging due to comple... Selective Laser Melting(SLM),an advanced metal additive manufacturing technology,offers high precision and personalized customization advantages.However,selecting reasonable SLM parameters is challenging due to complex relationships.This study proposes a method for identifying the optimal process window by combining the simulation model with an optimization algorithm.JAYA is guided by the principle of preferential behavior towards best solutions and avoidance of worst ones,but it is prone to premature convergence thus leading to insufficient global search.To overcome limitations,this research proposes a Differential Evolution-framed JAYA algorithm(DEJAYA).DEJAYA incorporates four key enhancements to improve the flexibility of the original algorithm,which include DE framework design,horizontal crossover operator,longitudinal crossover operator,and global greedy strategy.The effectiveness of DEJAYA is rigorously evaluated by a suite of 23 distinct benchmark functions.Furthermore,the numerical simulation establishes AlSi10Mg single-track formation models,and DEJAYA successfully identified the optimal process window for this problem.Experimental results validate that DEJAYA effectively guides SLM parameter selection for AlSi10Mg. 展开更多
关键词 Selective laser melting differential evolution-framed JAYA meta-heuristic algorithm AlSi10Mg singletrack formation optimal process window
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Hot Compression Deformation Behavior and Processing Maps of Mg-Zn-Mn(-Sn)-Ca Alloy
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作者 Chen Xia Zhu Yulong +2 位作者 Liu Quanyi Zhang Dingfei Pan Fusheng 《稀有金属材料与工程》 北大核心 2026年第3期627-635,共9页
The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from... The hot compression deformation behavior of Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca)and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca)alloys was investigated at deformation temperatures ranging from 250℃to 400℃and strain rates varying from 0.001 s^(-1) to 1 s^(-1).The results show that the addition of Sn promotes dynamic recrystallization(DRX),and CaMgSn phases can act as nucleation sites during the compression deformation.Flow stress increases with increasing the strain rate and decreasing the temperature.Both the ZM61-0.5Ca and ZMT612-0.5Ca alloys exhibit obvious DRX characteristics.CaMgSn phases can effectively inhibit dislocation motion with the addition of Sn,thus increasing the peak fl ow stress of the alloy.The addition of Sn increases the hot deformation activation energy of the ZM61-0.5Ca alloy from 199.654 kJ/mol to 276.649 kJ/mol,thus improving the thermal stability of the alloy.For the ZMT612-0.5Ca alloy,the optimal hot deformation parameters are determined to be a deformation temperature range of 350–400℃and a strain rate range of 0.001–0.01 s^(-1). 展开更多
关键词 hot deformation constitutive equation processing map deformation activation energy magnesium alloy
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Transformation of Verbal Descriptions of Process Flows into Business Process Modelling and Notation Models Using Multimodal Artificial Intelligence:Application in Justice
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作者 Silvia Alayón Carlos Martín +3 位作者 Jesús Torres Manuel Bacallado Rosa Aguilar Guzmán Savirón 《Computer Modeling in Engineering & Sciences》 2026年第2期870-892,共23页
Business Process Modelling(BPM)is essential for analyzing,improving,and automating the flow of information within organizations,but traditional approaches based on manual interpretation are slow,error-prone,and requir... Business Process Modelling(BPM)is essential for analyzing,improving,and automating the flow of information within organizations,but traditional approaches based on manual interpretation are slow,error-prone,and require a high level of expertise.This article proposes an innovative alternative solution that overcomes these limitations by automatically generating comprehensive Business Process Modelling and Notation(BPMN)diagrams solely from verbal descriptions of the processes to be modeled,utilizing Large Language Models(LLMs)and multimodal Artificial Intelligence(AI).Experimental results,based on video recordings of process explanations provided by an expert from an organization(in this case,the Commercial Courts of a public justice administration),demonstrate that the proposed methodology successfully enables the automatic generation of complete and accurate BPMN diagrams,leading to significant improvements in the speed,accuracy,and accessibility of process modeling.This research makes a substantial contribution to the field of business process modeling,as its methodology is groundbreaking in its use of LLMs and multimodal AI capabilities to handle different types of source material(text and video),combining several tools to minimize the number of queries and reduce the complexity of the prompts required for the automatic generation of successful BPMN diagrams. 展开更多
关键词 process modelling verbal description BPMN LLM multimodal AI
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Microstructural evolution and tensile deformation behaviors of fine-grained Fe_(40)Mn_(20)Co_(20)Cr_(15)Si_(5)high entropy alloy prepared by friction stir processing
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作者 Jia LIN Yuan FANG +7 位作者 Wen WANG Peng HAN Ting ZHANG Qiang LIU Ya-ting XIANG Feng-ming QIANG Ke QIAO Kuai-she WANG 《Transactions of Nonferrous Metals Society of China》 2026年第3期842-854,共13页
A fine-grained metastable dual-phase Fe_(40)Mn_(20)Co_(20)Cr_(15)Si_(5)high entropy alloy(CS-HEA)with excellent strength and ductility was successfully prepared by friction stir processing(FSP).The microstructural and... A fine-grained metastable dual-phase Fe_(40)Mn_(20)Co_(20)Cr_(15)Si_(5)high entropy alloy(CS-HEA)with excellent strength and ductility was successfully prepared by friction stir processing(FSP).The microstructural and mechanical properties of the fine-grained CS-HEA were characterized.The results showed that as-cast shrinkage cavities and elemental segregation were eliminated.The average grain size was refined from 121.1 to 5.4μm.The face-centered cubic phase fraction increased from 23%to 82%.During tensile deformation,dislocation slip dominated at strains ranging from 5%to 17%,followed by transformation induced plasticity(TRIP)from 17%to 26%,and twin induced plasticity(TWIP)from 26%to 37%.The yield strength,ultimate tensile strength,and elongation of the fine-grained CS-HEA were 503 MPa,1120 MPa,and 37%,respectively.The strength-ductility synergy of fine-grained CS-HEA was attributed to the combined effects of TRIP,TWIP,dislocation strengthening,and fine-grained strengthening. 展开更多
关键词 friction stir processing metastable high entropy alloy fine-grained microstructure deformation behaviors transformation-induced plasticity
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郭为与他的AI for Process
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作者 姜奇平 端利涛 《互联网周刊》 2026年第2期8-12,共5页
一、作为哲学的AI for Process(一)郭为的哲学思想1.郭为是谁郭为是谁?他是一位哲学家。顺便说,他同时还领导着神州数码。为什么说郭为是哲学家呢?因为他在著作中谈到高深的哲学,如“数据如水,奔流不息,无界融合”。他引述古希腊哲学家... 一、作为哲学的AI for Process(一)郭为的哲学思想1.郭为是谁郭为是谁?他是一位哲学家。顺便说,他同时还领导着神州数码。为什么说郭为是哲学家呢?因为他在著作中谈到高深的哲学,如“数据如水,奔流不息,无界融合”。他引述古希腊哲学家赫拉克利特所说的“万物流转”,又说“你不能两次踏进同一条河流,因为新的水不断地流过你的身旁”,他所表达的意思是“世界上唯一不变的就是变化”。 展开更多
关键词 AI for process 郭为
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Low-Temperature Superplastic Deformation Behavior of Bimodal Microstructure of Friction Stir Processed Ti-6Al-4V Alloy 被引量:2
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作者 H.Q.Dai N.Li +6 位作者 L.H.Wu J.Wang P.Xue F.C.Liu D.R.Ni B.L.Xiao Z.Y.Ma 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1559-1569,共11页
For a long time,the conventional superplastic forming temperature for Ti alloys is generally too high(~900-920℃),which leads to too long production cycles,heavy surface oxidation,and property reduction.In this study,... For a long time,the conventional superplastic forming temperature for Ti alloys is generally too high(~900-920℃),which leads to too long production cycles,heavy surface oxidation,and property reduction.In this study,an ultrafine bimodal microstructure,consisting of ultrafine equiaxed microstructure(0.66μm)and 43.3%lamellar microstructure,was achieved in the Ti-6Al-4V alloy by friction stir processing(FSP).The low-temperature superplastic behavior and deformation mechanism of the FSP Ti-6Al-4V alloy were investigated at temperatures of 550-675℃and strain rates ranging from 1×10^(−4)to 3×10^(−3)s^(−1).The FSP alloy exhibited superplastic elongations of>200%at the temperature range from 550 to 650℃,and an optimal superplastic elongation of 611%was achieved at 625℃and 1×10^(−4)s^(−1).This is the first time to report the low-temperature superplasticity of the bimodal microstructure in Ti alloys.Grain boundary sliding was identified as the dominant deformation mechanism,which was effectively accommodated by the comprehensive effect of dislocation-inducedβphase precipitation and dynamic spheroidization of the lamellar structure.This study provides a novel insight into the low-temperature superplastic deformation behavior of the bimodal microstructure. 展开更多
关键词 Titanium alloys Friction stir processing SUPERPLASTICITY Bimodal microstructure SPHEROIDIZATION
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Origin and Evolution Process of Overpressure in the Shahezi Formation of Xujiaweizi Fault Depression in the Northern Songliao Basin,NE China 被引量:1
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作者 ZHANG Chengju JIANG Zhenxue +7 位作者 LU Jiamin SHI Lidong BI Zhongyu SUN Lidong YANG Liang LI Xiaomei LIU Jiajun MIAO Huan 《Acta Geologica Sinica(English Edition)》 2025年第1期212-227,共16页
It is of great significance for deep oil and gas exploration to understand the origin and evolution behind overpressure.Overpressure occurs in the deep Shahezi Formation of Xujiaweizi fault depression.However,due to l... It is of great significance for deep oil and gas exploration to understand the origin and evolution behind overpressure.Overpressure occurs in the deep Shahezi Formation of Xujiaweizi fault depression.However,due to limited degree of exploration,there are some problems in the study area,such as unclear understanding of the origin of overpressure and the vague investigation of overpressure evolution.To clarify the impact of overpressure on oil and gas migration and accumulation in the study area,this study focuses on the research of the origin and evolution of overpressure in the Shahezi Formation of the study area,utilizing single well logging parameters and combining methods such as microthermometry of fluid inclusions,laser Raman spectrum,and basin simulation.The results show that the overpressure of the Shahezi Formation in Xujiaweizi fault depression is primarily generated by hydrocarbon generation pressurization,and the evolution of overpressure is closely related to hydrocarbon generation.The development of overpressure can be divided into two evolutionary stages:early hydrocarbon generation pressurization and late uplift release,with slight variations in different regions.Tight glutenite gas reservoirs in the Shahezi Formation are characterized by continuous charging.The overall charging period ranges from the late Denglouku to the early Mingshui(110-67 Ma ago).There is an obvious paleo-overpressure during the gas reservoir formation period.The gas generation period of source rocks occurred approximately 125-60 Ma ago,and the main gas generation period(112-67 Ma ago)highly coincides with the period of natural gas charging.The anomalously high pressure during the accumulation period is considered the significant driving force for natural gas charging.In addition,the sustained effect of overpressure provides better conditions for the preservation of tight gas reservoirs within the source.The results of the study are of guiding significance for the in-depth exploration and development of deep tight sandstone gas in the Shahezi Formation of Xujiaweizi fault depression. 展开更多
关键词 fluid inclusion laser Raman spectrum basin simulation overpressure genesis paleo-pressure recovery Shahezi formation Xujiaweizi fault depression
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Three-step formation of diamonds in shock-compressed hydrocarbons:Dissociation,species separation,and nucleation
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作者 Bo Chen Qiyu Zeng +4 位作者 Xiaoxiang Yu Jiahao Chen Shen Zhang Dongdong Kang Jiayu Dai 《Matter and Radiation at Extremes》 2026年第1期58-67,共10页
The accumulation and circulation of carbon and hydrogen contribute to the chemical evolution of ice giant planets.Species separation and diamond precipitation have been reported in carbon-hydrogen systems and have bee... The accumulation and circulation of carbon and hydrogen contribute to the chemical evolution of ice giant planets.Species separation and diamond precipitation have been reported in carbon-hydrogen systems and have been verified by static and shock compression experiments.Nevertheless,the dynamic formation processes underlying these phenomena remain insufficiently understood.In combination with a deep learning model,we demonstrate that diamonds form through a three-step process involving dissociation,species separation,and nucleation processes.Under shock conditions of 125 GPa and 4590 K,hydrocarbons decompose to give hydrogen and low-molecular-weight alkanes(CH_(4) and C_(2)H_(6)),which escape from the carbon chains,resulting in C/H species separation.The remaining carbon atoms without C-H bonds accumulate and nucleate to form diamond crystals.The process of diamond growth is associated with a critical nucleus size at which the dynamic energy barrier plays a key role.These dynamic processes of diamond formation provide insight into the establishment of a model for the evolution of ice giant planets. 展开更多
关键词 diamond formation formation processes ice giant planetsspecies separation DISSOCIATION deep learning modelwe carbon hydrogen static shock compression experimentsneverthelessthe chemical evolution
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Hot Deformation Behavior and Processing Map of Zr-Sn-Nb-Fe-Cr Alloy
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作者 Li Yuli Li Hao +3 位作者 Chen Qiuyu Zhou Xuan Ma Tianyang Sun Taotao 《稀有金属材料与工程》 北大核心 2025年第7期1671-1677,共7页
The hot deformation characteristics of induction quenched Zr-Sn-Nb-Fe-Cr alloy forged rod in the temperature range of 600–900°C and strain rate range of 0.001–1 s^(-1)were studied by Gleeble3800 uniaxial hot co... The hot deformation characteristics of induction quenched Zr-Sn-Nb-Fe-Cr alloy forged rod in the temperature range of 600–900°C and strain rate range of 0.001–1 s^(-1)were studied by Gleeble3800 uniaxial hot compression experiment.The results show that the flow stress decreases with the decrease in strain rate and the increase in deformation temperature in the true stress-true strain curve of Zr-Sn-Nb-Fe-Cr alloy forged rod.Moreover,the hot deformation characteristics of the material can be described by the hyperbolic sine constitutive equation.Under the experimental conditions,the average thermal activation energy(Q)of the alloy was 412.9105 kJ/mol.The microstructure analysis of the processing map and the sample after hot compression shows that the optimum hot working parameters of the alloy are 795–900°C,0.001–0.0068 s^(-1),at the deformation temperature of 600–900°C,and the strain rate of 0.001–1 s^(-1). 展开更多
关键词 zirconium alloy constitutive equation hot deformation processing map
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Hot Deformation Behavior and Processing Map of 23Cr-8Ni Steel
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作者 Zhang Baowei Niu Jiajia +4 位作者 Zeng Zhiwei Wang Xian Zhang Yuxiang Huang Dong Gao Zhenpeng 《稀有金属材料与工程》 北大核心 2025年第10期2501-2508,共8页
Using a Gleeble 3500 thermomechanical simulation testing machine,the hot deformation characteristics of 23Cr-8Ni steel were investigated under the conditions of 1000–1250℃ and 0.001‒10 s^(−1).Furthermore,the microst... Using a Gleeble 3500 thermomechanical simulation testing machine,the hot deformation characteristics of 23Cr-8Ni steel were investigated under the conditions of 1000–1250℃ and 0.001‒10 s^(−1).Furthermore,the microstructure of the characterization region was analyzed to investigate the recrystallization behavior of 23Cr-8Ni steel.Results show that as the strain rate decreases and the deformation temperature increases,the flow stress decreases.Because the softening phenomenon occurs after the peak stress,the flow stress decreases.The stress index(n)is 4.28,and the thermal deformation activation energy(Q)is 588878 J/mol.Processing map is established,and an optimal thermal processing range of 0.001–0.1 s^(−1) and 1000–1200℃ is achieved,therefore greatly promoting the yield rate. 展开更多
关键词 hot deformation behavior processing map 23Cr-8Ni steel GLEEBEL 3500
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Dynamic Regulation of Biofilm Formation and Metabolic Processes in Bacillus cereus Under Different Culture Conditions
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作者 DONG Xinyu XI Dongmin +4 位作者 MA Yining YANG Yongxin SHI Yan SUN Jingxin TAN Yulong 《Journal of Ocean University of China》 2025年第5期1414-1420,共7页
Bacillus cereus is a significant pathogen responsible for toxin-induced foodborne diseases,and is widely distributed in the natural environment.B.cereus biofilm formation is regulated by multifactorial interactions,de... Bacillus cereus is a significant pathogen responsible for toxin-induced foodborne diseases,and is widely distributed in the natural environment.B.cereus biofilm formation is regulated by multifactorial interactions,demonstrating dynamic adaptability to environmental cues.In this study,crystal violet staining and MTT staining methods were employed to conduct an indepth investigation into the biofilm formation and metabolic activity changes of five strains of B.cereus in different culture media and with various culture conditions.Experimental data indicated that the composition of the culture medium,the length of incubation time,and the fluctuation of temperature all had a significant impact on the biofilm formation of B.cereus,and this impact exhibited obvious differences among different strains.This result provides a solid experimental basis for deeply elucidating the internal regulatory mechanism of B.cereus biofilm formation and the change principles of metabolic activity. 展开更多
关键词 Bacillus cereus foodborne diseases biofilm formation metabolic activity culture conditions
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Void Formation Analysis in the Molded Underfill Process for Flip-Chip Packaging
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作者 Ian Hu Tzu-Chun Hung +2 位作者 Mu-Heng Zhou Heng-Sheng Lin Dao-Long Chen 《Computers, Materials & Continua》 2025年第7期537-551,共15页
Flip-chip technology is widely used in integrated circuit(IC)packaging.Molded underfill transfer molding is the most common process for these products,as the chip and solder bumps must be protected by the encapsulatin... Flip-chip technology is widely used in integrated circuit(IC)packaging.Molded underfill transfer molding is the most common process for these products,as the chip and solder bumps must be protected by the encapsulating material to ensure good reliability.Flow-front merging usually occurs during the molding process,and air is then trapped under the chip,which can form voids in the molded product.The void under the chip may cause stability and reliability problems.However,the flow process is unobservable during the transfer molding process.The engineer can only check for voids in the molded product after the process is complete.Previous studies have used fluid visualization experiments and developed computational fluid dynamics simulation tools to investigate this issue.However,a critical gap remains in establishing a comprehensive three-dimensional model that integrates two-phase flow,accurate venting settings,and fluid surface tension for molded underfill void evaluation—validated by experimental fluid visualization.This study aims to address this gap in the existing literature.In this study,a fluid visualization experiment was designed to simulate the transfer molding process,allowing for the observation of flow-front merging and void formation behaviors.For comparison,a three-dimensional mold flow analysis was also performed.It was found that the numerical simulation of the trapped air compression process under the chip was more accurate when considering the capillary force.The effect of design factors is evaluated in this paper.The results show that the most important factors for void size are fluid viscosity,the gap height under the chip,transfer time,contact angle between the fluid and the contact surfaces,and transfer pressure.Specifically,a smaller gap height beneath the chip aggravates void formation,while lower viscosity,extended transfer time,reduced contact angle,and increased transfer pressure are effective in minimizing void size.The overall results of this study will be useful for product and process design in selecting appropriate solutions for IC packaging,particularly in the development of void-free molded-underfill flip-chip packages.These findings support the optimization of industrial packaging processes in semiconductor manufacturing by guiding material selection and process parameters,ultimately enhancing package reliability and yield. 展开更多
关键词 Flip chip transfer molding molded underfill void formation capillary force
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Zircon U-Pb ages of the volcanic rocks and their constraints on the ending of the Huoshiling Formation in the southeastern of Songliao Basin,NE China 被引量:1
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作者 Xue-jiao Qu Ming-kai Zhang +5 位作者 Pu-jun Wang Zhuo-long Yang You-feng Gao Kang-jun Wu Jia Wang Xian-feng Tan 《China Geology》 2026年第1期214-216,I0023,共4页
1.Objective The Songliao Basin(SB)is situated on the eastern margin of Eurasia continent(Northeast Asia).During the Late Jurassic to Early Cretaceous,hundreds of rifting basins developed in this area,and the SB is a u... 1.Objective The Songliao Basin(SB)is situated on the eastern margin of Eurasia continent(Northeast Asia).During the Late Jurassic to Early Cretaceous,hundreds of rifting basins developed in this area,and the SB is a unique case among them as it evolved into the largest rift basin.The rift basin filling of SB includes Huoshiling Formation,Shahezi Formation,and Yingcheng Formation in ascending order.The mega-rifting was controlled by the Mongol-Okhotsk Collisional Belt to the north and northwest and the Pacific Subduction Zone to the east(Wang PJ et al.,2016).As the first rifting succession,the Huoshiling Formation contains key information about the formation of the rifting basins and records the evolution of the Mongol-Okhotsk Collisional Belt and the Pacific Subduction Zone.However,the geological period of the Huoshiling Formation has not been well constrained for two main reasons.First,it is easily confused with the Yingcheng Formation,as both are dominated by volcanogenic-sedimentary successions.Second,there is lack of reliable dating samples from the uppermost part of the Huoshiling Formation due to its considerable burial depth. 展开更多
关键词 rift basin rift basinthe yingcheng formation ZIRCON U Pb ages rifting basins volcanic rocks huoshiling formationshahezi formationand
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Modeling of austenite formation kinetics overlapping recrystallization in cold-rolled Q&P steel during ultrafast heating process
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作者 Jiang Chang Mai Wang +2 位作者 Yong-gang Yang Yan-xin Wu Zhen-li Mi 《Journal of Iron and Steel Research International》 2025年第11期3894-3907,共14页
The cold-rolled quenching and partitioning(Q&P)steel with an initial microstructure of deformed ferrite and pearlite was studied.The microstructural evolution under various heating rates of 1.78,50,and 300℃/s was... The cold-rolled quenching and partitioning(Q&P)steel with an initial microstructure of deformed ferrite and pearlite was studied.The microstructural evolution under various heating rates of 1.78,50,and 300℃/s was investigated using microstructural characterization and theoretical modeling.At the same time,the characteristics of recrystallization and austenite formation kinetics were decoupled by examining recrystallized ferrite and deformed ferrite as initial conditions.The findings revealed that the austenite formation during continuous heating can be simplified into two stages:(i)the early nucleation-dominated formation stage and(ii)the later grain growth-dominated stage,resulting in the development of a modified two-stage model based on Johnson-Mehl-Avrami-Kolmogorov.Further experiments confirmed that when the austenite volume fraction exceeded approximately 5% at a heating rate of 1.78℃/s,ferrite recrystallization was suppressed.In consequence,a mixed model including recrystallization kinetics was employed to couple the austenite formation occurring in deformed ferrite and recrystallized ferrite,thereby describing the austenite formation kinetics affected by recrystallization.Precise predictions of non-isothermal austenite formation kinetics in cold-rolled Q&P steel were achieved during slow and ultrafast heating processes by integrating the suppression effect into the model for austenite formation. 展开更多
关键词 Quenching and partitioning steel Ultrafast heating Ferrite recrystallization Austenite formation Kinetic model
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Depositional history,contact relationships,and characterization of Upper Miocene Baogeda Ula Formation in central Nei Mongol with a description of fossil skunks
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作者 WANG Xiao-Ming SUN Lu +3 位作者 LI Lu LI Qiang QIU Zhu-Ding Zhijie Jack TSENG 《古脊椎动物学报(中英文)》 北大核心 2026年第1期100-124,共25页
In addition to its well-known fossils,the Upper Miocene Baogeda Ula Formation is coupled with multiple basaltic lava flows,creating an ideal setting for studying its depositional history,geochronology,and associated v... In addition to its well-known fossils,the Upper Miocene Baogeda Ula Formation is coupled with multiple basaltic lava flows,creating an ideal setting for studying its depositional history,geochronology,and associated vertebrate fossils.This paper,in honor of Prof.Qiu Zhanxiang for his widely admired emphasis on the geological contexts of vertebrate fossils,attempts to synthesize known contact relationships,existing K-Ar dates,and capping basalt elevations to reframe our concept of the lithostratigraphy,magnetostratigraphy,and lateral distribution of the Baogeda Ula Formation.Within this new framework,the Baogeda Ula Formation is defined by unconformable contact with the underlying Tunggur Formation at the lower boundary and a capping basalt at the upper boundary.In many sections,two or three layers of basalts are interbedded within sedimentary strata,with the capping basalts typically belonging to the top two basalts.The newly defined Baogeda Ula Formation includes a lower member as exemplified by Halajin Hushu section and Ulan Hushuyin Nur section,and an upper member at Baogeda Ula section.This expanded concept of the Baogeda Ula Formation includes two major faunas,i.e.,the Bahean Halajin Hushu Fauna and Baodean Baogeda Ula Fauna,both falling within the Upper Miocene.We also describe rare fossil skunks(Promephitis)found in recent years that support the age assessments presented herein. 展开更多
关键词 Nei Mongol MIOCENE Baogeda Ula formation STRATIGRAPHY skunks
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Role of Surface Processes and Mantle Plumes in the Formation of Microcontinents:Insights from Numerical Modeling and the Seychelles Microcontinent Case Study
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作者 Zhijie Jia Pietro Sternai Jianbing Peng 《Journal of Earth Science》 2025年第1期233-249,共17页
Mantle plumes and surface erosion and sediment deposition affect the modes of continental lithospheric rupturing in extensional tectonic settings,modulating the evolution of rifting margins.However,their relative cont... Mantle plumes and surface erosion and sediment deposition affect the modes of continental lithospheric rupturing in extensional tectonic settings,modulating the evolution of rifting margins.However,their relative contributions to the overall evolution of rifting margins and possible roles in the formation of microcontinent are still elusive.Here,we use coupled geodynamic and surface processes numerical modeling to assess the extent to which surface processes may determine the formation of microcontinent during lithospheric stretching in presence or absence of a mantle plume underneath.Our modeling results indicate that fast extension rates and hillslope(i.e.,diffusion)erosion promote ridge jump events and therefore the formation of microcontinents.On the contrary,efficient fluvial erosion and far-reaching sediment transport(i.e.,stream power erosion)inhibits ridge jump events and the formation of microcontinents.The ridge jump event and overall evolution in our numerical models is consistent with the shift from the Mascarene Ridge to the Carlsberg Ridge that determined the formation of the Seychelles microcontinent.We therefore speculate that hillslope erosion,rather than fluvial erosion,was predominant during the formation of the Seychelles,a possible indication of overall dry local climate conditions. 展开更多
关键词 continental rifting surface processes mantle plume seychelles microcontinent surface reactions
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Research on the degradation mechanism,product effects and optimization strategy of the tributyl phosphate solvent system in the PUREX process
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作者 Tian Lan Jiaxin Liu Yi Liu 《Smart Molecules》 2026年第1期31-44,共14页
While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its susta... While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its sustainable development.The PUREX(plutonium uranium redox extraction)process is currently the dominant nuclear fuel reprocessing technology in the world.However,the key extractant in this process is tributyl phosphate(TBP),which degrades under intense radiation,high temperatures,and strong acidity.This leads to the production of dibutyl phosphate,monobutyl phosphate,and other degradation byproducts,which may reduce the extraction efficiency and trigger third-phase formation and equipment corrosion.This paper systematically reviews the degradation mechanisms of TBP and its diluents,the analytical technique suitable for characterizing degradation products,and the impact of degradation products on the post-treatment process.Additionally,optimization strategies employed for suppressing third-phase formation are discussed.This study offers a theoretical foundation and technical insights in optimizing the PUREX process and ensuring the safe operation of the post-treatment process. 展开更多
关键词 degradation products PUREX process solvent degradation third-phase formation tributyl phosphate(TBP)
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In-situ TEM investigation on the crystallization transformation process of rare earth oxide luminescent materials
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作者 Zhipeng Xu Wenzhe Zhang +2 位作者 Shenao Zhang Fukang Xing Yang Zhang 《Rare Metals》 2025年第11期8823-8831,共9页
Self-template transformations are widely used for preparation of lanthanide(Ln^(3+))based nanoparticles with tunable porosity and composition,considering of their outstanding performance in optical,drug delivery and b... Self-template transformations are widely used for preparation of lanthanide(Ln^(3+))based nanoparticles with tunable porosity and composition,considering of their outstanding performance in optical,drug delivery and bioimaging.However,it is still a major challenge to characterize the crystallization process,morphology and composition changes of these nanostructures in atomic scale and three-dimensional(3D).In this paper,we investigate the transformation of amorphous precursor to porous Y_(2)O_(3):Eu^(3+)nanocrystals with advanced microscopy techniques.The morphology changes and compositions under different temperatures are identified through in-situ microscopy.The porous structures in 3D is clearly studied via electron tomography.Insights from this research are of broader interest for the class of transformation reactions,which will definitely shed light on the synthesis of complex nanostructures. 展开更多
关键词 Rare earth Luminescent materials ATOMIC Crystallization process Eu^(3+)
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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2026年第4期I0011-I0011,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of significant,novel,and high-impact research in the fields of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 processING Agricultural Products Consumer Demand
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Hot Deformation Behavior of CoNiV Medium-Entropy Alloy:Constitutive Model,Convolutional Neural Network,Hot Processing Map,and Microstructure Evolution
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作者 Biao Zhang Yuntian Du +6 位作者 Huishuang Jia Yuanyi Zhou Liguang Wang Minghe Zhang Yunli Feng Weimin Gao Ning Xu 《Acta Metallurgica Sinica(English Letters)》 2025年第8期1275-1292,共18页
This study systematically investigates the hot deformation behavior and microstructural evolution of CoNiV medium-entropy alloy(MEA)in the temperature range of 950-1100℃ and strain rates of 0.001-1 s^(-1).The Arrheni... This study systematically investigates the hot deformation behavior and microstructural evolution of CoNiV medium-entropy alloy(MEA)in the temperature range of 950-1100℃ and strain rates of 0.001-1 s^(-1).The Arrhenius model and machine learning model were developed to forecast flow stresses at various conditions.The predictive capability of both models was assessed using the coefficients of determination(R^(2)),average absolute relative error(AARE),and root mean square error(RMSE).The findings show that the osprey optimization algorithm convolutional neural network(OOA-CNN)model outperforms the Arrhenius model,achieving a high R^(2) value of 0.99959 and lower AARE and RMSE values.The flow stress that the OOA-CNN model predicted was used to generate power dissipation maps and instability maps under different strains.Finally,combining the processing map and microstructure characterization,the ideal processing domain was identified as 1100℃ at strain rates of 0.01-0.1 s^(-1).This study provided key insights into optimizing the hot working process of CoNiV MEA. 展开更多
关键词 Hot deformation Arrhenius model Machine learning CoNiV MEA Hot processing map
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