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Preparation and Microstructure Evaluation of Directionally Solidified Nd-Fe-B Ingots by Electromagnetic Cold Crucible

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Journal of Iron and Steel Research International 2012年第S1期19卷 237-242页

作者： DING Hong-sheng FENG Kui WANG Yong-zhe chen rui-run GUO Jing-jie National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of Technology

In this paper Nd-Fe-B ingots with hyper-peritectic composition were prepared through continuous and directional solidification by a novel electromagnetic cold crucible approach.A group of experiments were carried out in order to investigate the effects of input power and withdrawal velocity on the microstructure and growth orientation of Nd-Fe-B *** was found that the peritectic Nd;Fe;B phase grows with a planar interface at lower withdrawal velocity and changed into the dendritic interface at higher withdrawal *** result was explained by the theory of constitutional *** the volume fraction of ferromagnetic T;phase was found to be increased first and then decreased with the increasing of withdrawal velocity during the growth process of the ingots.

关键词： electromagnetic cold crucible directional solidification Nd-Fe-B structure ferromagnetic phase

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu run Hou chenghao Wu ruishan Xie Shujun chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing Research Institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

Lightweight Al-Nb-Ti-V-Cr high entropy alloys with high hardness and enhanced mechanical properties via doping Co

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China Foundry 2025年

作者： Fang-dong Xu De-zhi chen rui-run chen Bin Gan Jing-yue Yu National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Suzhou Laboratory

To develop high-hardness and high-strength lightweight high entropy alloys （LHEAs）,a series of CoxAlNbTiVCr alloys were *** phase constitution,distribution,and crystal structure of the Laves phase in alloys can be altered by adjusting the composition of HEAs,which in turn influences their mechanical *** Nb Ti VCr （x=0,0.5,1,1.5,and 2,atomic ratio percentage） LHEAs were designed and prepared to characterize the microstructure and tailor the mechanical *** introduction of Co changes the microstructure of LHEAs from a single B2 structure to a mixture dendrite structure,which consists of B2 phase,C14 and C15 Laves *** the C14 and C15 Laves phases exhibit coupled *** parameters including mixing enthalpy (ΔHmix),valence electron concentration （VEC）,atomic radius size （δ）,mixing entropy （ΔS）,and electronegativity difference （Δχ） are used to predict the formation of B2 and Laves phase in *** the Co content increases from 0 to 1.5at.%,Laves phase volume fraction gradually increases,which leads to an enhancement in the compressive strength from 1,520.8 MPa to 1,844.4 ***1.5Al Nb Ti VCr alloy exhibits the maximum Vickers hardness of 699.4 *** improvement of mechanical properties mainly originates from solid solution strengthening and second phase strengthening.

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Electrospraying Si/SiO_(x)/C and Sn/C nanosphere arrays on carbon cloth for high-performance flexible lithium-ion batteries

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Journal of Semiconductors 2025年第1期46卷 234-243页

作者： Di chen rui Li Chunxue Liu Kai Jiang School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China College of Physics and Mathematics University of Science and TechnologyBeijing 100083China Falculty of Hepato-Pancreato-Biliary Surgery Chinese PLA General HospitalInstitute of Hepatobiliary Surgery of Chinese PLA& Key Laboratory of Digital Hepetobiliary SurgeryChinese PLABeijing 100853China

Exploring electrode materials with larger capacity,higher power density and longer cycle life was critical for developing advanced flexible lithium-ion batteries(LIBs).Herein,we used a controlled two-step method including electrospraying followed with calcination treatment by CVD furnace to design novel electrodes of Si/Si_(x)/C and Sn/C microrods array consisting of nanospheres on flexible carbon cloth substrate(denoted as Si/Si_(x)/C@CC,Sn/C@CC).Microrods composed of cumulated nanospheres(the diameter was approximately 120 nm)had a mean diameter of approximately 1.5μm and a length of around 4.0μm,distributing uniformly along the entire woven carbon *** of Si/Si/Si_(x)/C@CC and Sn/C@CC products were synthesized as binder-free anodes for Li-ion battery with the features of high reversible capacity and excellent *** Si/Six/C electrode exhibited high specific capacity of about 1750 mA∙h∙g^(−1)at 0.5 A∙g^(−1)and excellent cycling ability even after 1050 cycles with a capacity of 1388 mA∙h∙g^(−1).Highly flexible Si/Si_(x)/C@CC//LiCoO_(2)batteries based on liquid and solid electrolytes were also fabricated,exhibiting high flexibility,excellent electrical stability and potential applications in flexible wearable electronics.

关键词： electrospraying Si/SiO_(x)/C Sn/C lithium-ion batteries

Spherical Magnetic Fe-Alginate Microgels Fabricated by Droplet-Microfluidics Combining with an External Crosslinking Approach and the Study of Their pH Dependent Fe^(3+) Release Behaviors

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Chinese Journal of Polymer Science 2025年第2期43卷 289-302页

作者： Jie chen run-Yu Yu ai-Qi Wang Zhe-Yu Zhang Arezoo Ardekani Yuan-Du Hu Department of Materials Science and Engineering School of Physics Science and EngineeringBeijing Jiaotong UniversityBeijing100044China Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing South China University of TechnologyGuangzhou510641China State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai200438China Department of Mathematics School of Mechanical EngineeringPurdue University585 Purdue MallWest LafayetteIN47907-2088USA

Due to the rapid development and potential applications of iron(Ⅲ)-alginate(Fe-Alg)microgels in biomedical as well as environmental engineering,this study explores the preparation and characterization of spherical Fe-Alg microgels using droplet microfluidics combined with an external ionic crosslinking *** study focused on the role of Fe^(3+)and examined its effects on the physical/chemical properties of microgels under different ionic conditions and reduced or oxidized *** pH-dependent release behavior of Fe^(3+)from these microgels demonstrates their potential biomedical and environmental ***,the microgels can exhibit magnetism simply by utilizing in situ oxidation,which can be further used for targeted drug delivery and magnetic separation technologies.

关键词： Fe-alginate microgels Droplet microfluidics In situ oxidation Magnetism

Numerical calculation of flow field inside TiAl melt during rectangular cold crucible directional solidification

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Transactions of Nonferrous Metals Society of China 2012年第1期22卷 157-163页

作者： YANG Jie-ren chen rui-run DING Hong-sheng SU Yan-qing HUANG Feng GUO Jing-jie FU Heng-zhi School of Materials Science and Engineering Harbin Institute of Techn ologyHarbin 150001China

Numerical investigations on the flow field in Ti-Al melt during rectangular cold crucible directional solidification were carried out. Combined with the experimental results, 3-D finite element models for calculating flow field inside melting pool were established, the characteristics of the flow under different power parameters were further studied. Numerical calculation results show that there is a complex circular flow in the melt, a rapid horizontal flow exists on the solid/liquid interface and those flows confluence in the center of the melting pool. The flow velocity v increases with the increase of current intensity, but the flow patterns remain unchanged. When the current is 1000 A, the vmax reaches 4 mm/s and the flow on the interface achieves 3 mm/s. Flow patterns are quite different when the frequency changes from 10 kHz to 100 kHz, the mechanism of the frequency influence on the flow pattern is analyzed, and there is an optimum frequency for cold crucible directional solidification.

关键词： flow field numerical calculation TiAl alloys cold crucible directional solidification

Mitochondrial dysfunction in the pathogenesis of acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2025年第1期24卷 76-83页

作者： Xia chen rui Zhong Bing Hu Department of Gastroenterology and Hepatology West China HospitalSichuan UniversityChengdu 610041China Department of Gastroenterology Clinical Medical College and The First Affiliated Hospital of Chengdu Medical CollegeChengdu 610500China

The mechanism of cell damage during acute pancreatitis (AP) has not been fully elucidated, and there is still a lack of specific or effective treatments. Increasing evidence has implicated mitochondrial dysfunction as a key event in the pathophysiology of AP. Mitochondrial dysfunction is closely related to calcium (Ca^(2+)) overload, intracellular adenosine triphosphate depletion, mitochondrial permeability transition pore openings, loss of mitochondrial membrane potential, mitophagy damage and inflammatory responses. Mitochondrial dysfunction is an early triggering event in the initiation and development of AP,and this organelle damage may precede the release of inflammatory cytokines, intracellular trypsin activation and vacuole formation of pancreatic acinar cells. This review provides further insight into the role of mitochondria in both physiological and pathophysiological aspects of AP, aiming to improve our understanding of the underlying mechanism which may lead to the development of therapeutic and preventive strategies for AP.

关键词： Acute pancreatitis Autophagy Calcium Cell death Inflammation Mitochondria Mitophagy

Novel Low-Carbon Optimal Operation Method for Flexible Distribution Network Based on Carbon Emission Flow

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Energy Engineering 2025年第2期122卷 785-803页

作者： Chao Gao Kai Niu Wenjing chen Changwei Wang Yabin chen rui Qu Guangdong-Hong Kong-Macao Greater Bay Area Construction Promotion Office of Guangdong Power Grid Co. Ltd.Guangzhou510030China School of Electrical Engineering Northeast Electric Power UniversityJilin132012China School of Electrical Engineering Fuzhou UniversityFuzhou350116China

With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FDN),the calculation of carbon flow distribution in FDN is more *** this end,this study constructs a model for low-carbon optimal operations within the FDN on the basis of enhanced carbon emission flow(CEF).First,the carbon emission characteristics of FDNs are scrutinized and an improved method for calculating carbon flow within these networks is ***,a model for optimizing low-carbon operations within FDNs is formulated based on the refined CEF,which merges the specificities of DG and intelligent ***,this model is scrutinized using an upgraded IEEE 33-node distribution system,a comparative analysis of the cases reveals that when DG and SOP are operated in a coordinated manner in the FDN,with the cost of electricity generation was reduced by 40.63 percent and the cost of carbon emissions by 10.18 *** findings indicate that the judicious optimization of areas exhibiting higher carbon flow rates can effectively enhance the economic efficiency of DN operations and curtail the carbon emissions of the overall network.

关键词： Flexible distribution network carbon emission flow distributed generation soft open points

Post-rifting magmatism at the northern margin of the South China Sea:Evidenced by an ocean bottom seismometer experiment

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Earthquake Science 2025年第1期38卷 1-16页

作者： Lu Zhang chen Cai rui Gao School of Earth Sciences and Engineering Sun Yat-sen UniversityGuangzhou 510275China School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Guangdong Provincial Key Lab of Geodynamics and Geohazards Guangzhou 510275China Guangdong Deep Earth Exploration and Geological Process Technology Research Center Guangzhou 510275China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

Magmatism at continental margins is of great significance in understanding the continental *** present a twodimensional P-wave velocity model derived from an ocean bottom seismometer experiment,conducted across the middle northern continental margin of the South China Sea(SCS).The detailed velocity structures reveal significant heterogeneities extending from the continental shelf to the continent-ocean transition *** crust exhibits its greatest thickness below the continental shelf,measuring~23 km and gradually thins to~13 km at the distal ***,a narrow and distinct continent-ocean transition with only 40-km width is *** also observe a high-velocity layer within the transition zone,reaching thickness of up to 4 km,characterized by P-wave velocities ranging from 7.0 km/s to 7.6 km/s in the lower *** on the syn-rift melt generation using decompression melting model,we ascertain that syn-rift magmatism cannot fully account for the observed thick high-velocity *** integrating findings from previous geophysical and geochemical studies presenting extensive volcanic edifice on the seafloor at the northern margin,as well as ocean-island-basalt-type magmaticsamples in the SCS area,we propose that post-rifting magmatism associated with the Hainan Plume may have influenced theformation of the high-velocity lower crust within the transition zone and the northern margin of the SCS can thus be recognizedas magma-poor type margin.

关键词： South China Sea continental margin seismic refraction post-rift magmatism