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Journal of Energy Chemistry 2024年第10期97卷 68-78页

作者： Cheng He Jianglong Ma Shen Xi Wenxue Zhang State Key Laboratory for mechanical Behavior of materials School of Materials Science and Engineering Xi'an Jiaotong University school of materials Science and engineering Chang'an University

Compared to single atom catalysts（SACs）,the introduction of dual atom catalysts（DACs） has a significantly positive effect on improving the efficiency in the electrocatalytic nitrogen reduction reaction（NRR） which provides an environmental alternative to the Haber-Bosch ***,the research on the mechanism and strategy of designing bimetallic combinations for better performance is still in its early ***,based on "blocking and rebalance" mechanism,45 combinations of bimetallic pair doped α-phosphorus carbide（TMATMB@PC） are investigated as efficient NRR catalysts through density functional theory and machine learning *** a multi-step screening,the combinations of TiV,TiFe,MnMo,and FeW exhibit highly efficient catalytic performance with significantly lower limiting potentials（-0.17,-0.18,-0.14,and-0.30 V,respectively）.Excitingly,the limiting potential for CrMo and CrW combinations is 0 V,which are considered to be extremely suitable for the NRR *** mechanism of "blocking and rebalance" is revealed by the exploration of charge transfer for phosphorus atoms in electron blocking ***,the descriptor φ is proposed with machine learning,which provides design strategies and accurate prediction for finding efficient *** work not only offers promising catalysts TMATMB@PC for NRR process but also provides design strategies by presenting the descriptor φ.

关键词： 2D α-phosphorus carbide DACs Inherent attributes Machine learning Nitrogen reduction reaction

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:materials International 2024年第2期34卷 376-388页

作者： Ling Zhang Yinglong Li school of materials Science and engineering Northeastern University school of mechanical and engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy mechanical performance Mg-Gd-Y-Zr alloy Texture development

Nickel Sulfide Modified NiCu Nanoalloy with Excellent Oxygen Evolution Reaction Properties Prepared through Electrospinning and Heat Treatment

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Journal of Wuhan University of Technology(materials Science) 2024年第2期39卷 320-326页

作者：李涛凌帅 ZHONG Shujie LOU Qiongyue Department of materials engineering School of Mechanical EngineeringChengdu UniversityChengdu 610106China

Ni^(2+)/Cu^(2+)/SO_(4)^(2-)/polyvinyl alcohol precursor fibers with uniform diameters were prepared through ***-based composite nanoalloys containing Ni,Cu,and S were prepared through heat treatment in an Ar *** experimental results show that the main components of the prepared nanoalloys are NiCu,Ni_(3)S_(2),Ni,and *** nanoalloys exhibit fine grain sizes about 200-500 nm,which can increase with increasing heat treatment *** test results show that the nickel sulfidemodified NiCu nanoalloy composites exhibit excellent oxygen evolution reaction properties,and the oxygen evolution reaction properties gradually improve with the increasing heat treatment *** sample prepared at 1 000℃ for 40 min show a low overpotential of 423 mV and a small Tafel slope of 134 mV·dec^(-1) at a current density of 10 mA·cm^(-2).

关键词： NiCu nanoalloy Ni_(3)S_(2) structure transformation oxygen evolution reaction

Numerical simulation on the multiphase flow and reoxidation of the molten steel in a two-strand tundish during ladle change

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International Journal of Minerals,Metallurgy and materials 2024年第7期31卷 1540-1553页

作者： Jingcheng Wang Zhentong Liu Wei Chen Hongliang Chen Lifeng Zhang school of mechanical engineering Yanshan UniversityQinhuangdao 066004China school of materials Science and engineering Tianjin UniversityTianjin 300350China school of mechanical and materials engineering North China University of TechnologyBeijing 100144China

A 3D mathematical model was proposed to investigate the molten steel–slag–air multiphase flow in a two-strand slab continuous casting(CC)tundish during ladle *** study focused on the exposure of the molten steel and the subsequent reoxidation *** exposure of the molten steel was calculated using the coupled realizable k–εmodel and volume of fluid(VOF)*** diffusion of dissolved oxygen was determined by solving the user-defined scalar(UDS)***,the user-defined function(UDF)was used to describe the source term in the UDS equation and determine the oxidation rate and oxidation *** effect of the refilling speed on the molten steel exposure and dissolved oxygen content was also *** the refilling speed during ladle change reduced the refilling time and the exposure duration of the molten ***,the elevated refilling speed enlarged the slag eyes and increased the average dissolved oxygen content within the tundish,thereby exacerbating the reoxidation *** addition,the time required for the molten steel with a high dissolved oxygen content to exit the tundish varied with the refilling *** the inlet speed was 3.0 m·s^(-1)during ladle change,the molten steel with a high dissolved oxygen content exited the outlet in a short period,reaching a maximum dissolved oxygen content of 0.000525wt%.Conversely,when the inlet speed was 1.8 m·s^(-1),the maximum dissolved oxygen content was 0.000382wt%.The refilling speed during the ladle change process must be appropriately decreased to minimize reoxidation effects and enhance the steel product quality.

关键词： tundish ladle change reoxidation multiphase flow numerical simulation

An experimental and theoretical study on photoluminescence of Ce^(3+)-doped ZnS quantum dots and their application in Aspergillus oryzae

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Journal of Rare Earths 2024年第6期42卷 1020-1028,I0001页

作者： Yan Lei Guangzhi Zhang Yitong Yao Gaiqin Zhu Zhong Chen Jiangrong Dan Hua Liu Shuwang Duo school of materials and mechanical and electrical engineeringJiangxi Science and Technology Normal University Nanchang330013China

ZnS and ZnS:3.125%Ce^(3+)(ZSC)quantum dots(QDs)were synthesized by a low-temperature solid-phase *** crystal structure,photoluminescence(PL)properties of ZSC QDs,and their effects on the growth and kojic acid production of Aspergillus oryzae(***)were *** is found that both QDs have a cubic blend structure with the average particle size ranging of 2.75-6.14 ***^(3+)doping not only increases the band gap of ZnS QDs from 3.43 to 3.48 eV,but also increases the PL intensity by about 2.23 times,which is due to the fact that the electron carrier concentration is improved,and then the rate of radiative recombination is *** integral emission intensity,biomass,extracellular proteins yield,and kojic acid production of *** cultured with ZSC(ZnS)QDs are about 4.31(3.23),1.61(1.20),1.12(1.09),and 2.99(1.68)times higher than that of medium without QDs,respectively.

关键词： Zns Quantum dots Doping First-principles calculations Aspergllus oryzae Rare earths

Effect of post heat treatment on microstructure, mechanical property and corrosion behavior of AlSi10Mg alloy fabricated by selective laser melting

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Progress in Natural Science:materials International 2024年第1期34卷 89-101页

作者： Yang Zheng Zihao Zhao Ruize Xiong Guochun Ren Minghui Yao Wei Liu Libin Zang school of Aeronautics and Astronautics Tiangong University school of mechanical engineering Tiangong University 3D Printing Research&engineering Technology Center AECC Beijing Institute of Aeronautical Materials Tianjin Institute of Aerospace mechanical and electrical Equipment

The microstructure, mechanical property and corrosion behavior of the AlSi10Mg alloy fabricated by selective laser melting(SLMed-AlSi10Mg) after different post heat treatment(PHT) of direct aging(DA), solid solution(T4)and solid solution + aging(T6) were investigated. The microstructural characterization revealed that the porosity of the SLMed-AlSi10Mg was increased from 0.41 ± 0.04 % to 3.09 ± 0.11 % with increasing temperature. The Asbuilt and DA-treated samples exhibited a microstructure of α-Al matrix surrounded with continuous Si networks,whereas the T4-treated and T6-treated samples presented a microstructure of α-Al matrix surrounded with discrete Si particles. The microhardness, strength and work hardening rate of the SLMed-AlSi10Mg increased in the order of T4-treated sample < T6-treated sample < As-built sample < DA-treated sample(a reverse order was found for the elongation), which was due to the precipitation of nanoscale Si particles after DA treatment and the softening of α-Al matrix after T4 and T6 treatments. The corrosion resistance of the SLMed-AlSi10Mg was obviously deteriorated after T4 and T6 treatments compared with DA treatment, which was caused by the changes in Si morphology, residual stress and porosity.

关键词： Selective laser melting AlSi10Mg alloy Post heat treatment Microstructure mechanical property Corrosion behavior

Lift-Off Effect of Koch and Circular Differential Pickup Eddy Current Probes

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Chinese Journal of mechanical engineering 2024年第2期37卷 283-293页

作者： Guolong Chen Zheng Cao Shuaishuai Zhang Ji Wei Wei Gao Wuyin Jin school of mechanical and electrical engineering Lanzhou University of TechnologyLanzhou 730050China

A flexible or planar eddy current probe with a differential structure can suppress the lift-off noise during the inspection of ***,the extent of the lift-off effect on differential probes,including different coil structures,*** this study,two planar eddy current probes with differential pickup structures and the same size,Koch and circular probes,were used to compare lift-off *** eddy current distributions of the probes perturbed by 0°and 90°cracks were obtained by finite element *** analysis results show that the 90°crack can impede the eddy current induced by the Koch probe even further at relatively low lift-off *** peak-to-peak values of the signal output from the two probes were compared at different lift-off distances using finite element analysis and experimental *** addition,the effects of different frequencies on the lift-off were studied *** results show that the signal peak-to-peak value of the Koch probe for the inspection of cracks in 90°orientation is larger than that of the circular probe when the lift-off distance is smaller than 1.2 *** addition,the influence of the lift-off distance on the peak-to-peak signal value of the two probes was studied via *** indicates that the influence becomes more evident with an increase in excitation *** research discloses the lift-off effect of differential planar eddy current probes with different coil shapes and proves the detection merit of the Koch probe for 90°cracks at low lift-off distances.

关键词： Eddy current testing Differential pickup probe Fractal Koch curve Flexible eddy current probe

Quasi-two dimensional Ruddlesden−Popper halide perovskites for laser applications

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Frontiers of physics 2024年第2期19卷 53-71页

作者： Kun Chen Qianpeng Zhang Yin Liang Jiepeng Song Chun Li Shi Chen Fang Li Qing Zhang school of mechanical and electrical engineering Wuhan Institute of TechnologyWuhan 430205China school of materials Science and engineering Peking UniversityBeijing 100871China Institute of Applied Physics and materials engineering Macao UniversityMacao 999078China

Quasi-two-dimensional(2D)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton binding energy,high emission yield,large optical gain,and wide-range tuning of optical *** review will introduce research progresses of RP halide perovskites for lasing applications in aspects of materials,photophysics,and devices with emphasis on emission and lasing properties tailored by the molecular composition and *** materials,structures and fabrications are introduced in the first ***,the optical transitions and amplified spontaneous emission properties are discussed from the aspects of electronic structure,exciton,gain dynamics,and interface ***,the research progresses on lasing devices are summarized and several types of lasers including VCSEL,DFB lasers,microlasers,random lasers,plasmonic lasers,and polariton lasers are *** last,the challenges and perspectives would be provided.

关键词： two-dimensional materials metal halide perovskite Ruddlesden−Popper halide perovskites lasing emission

Research of caged dynamics of clusters center atoms in Pd_(82)Si_(18) amorphous alloy

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Chinese Physics B 2024年第4期33卷 623-629页

作者：邓永和陈贝祁清华李兵兵高明文大东王小云彭平 school of Computational Science and Electronics Hunan Institute of EngineeringXiangtan 411104China school of Physics and mechanical&electrical engineering Jishou UniversityJishou 416000China school of materials Science and engineering Hunan UniversityChangsha 410082China

To date,there is still a lack of a comprehensive explanation for caged dynamics which is regarded as one of the intricate dynamic behaviors in amorphous *** study focuses on Pd_(82)Si_(18)as the research object to further elucidate the underlying mechanism of caged dynamics from multiple perspectives,including the cage's lifetime,atomic local environment,and atomic potential *** results reveal that Si atoms exhibit a pronounced cage effect due to the hindrance of Pd atoms,resulting in an anomalous peak in the non-Gaussian *** in-depth investigation was conducted on the caged dynamics differences between fast and slow Si *** comparison to fast Si atoms,slow Si atoms were surrounded by more Pd atoms and occupied lower potential energy states,resulting in smaller diffusion displacements for the slow Si ***,slow Si atoms tend to be in the centers of smaller clusters with coordination numbers of 9 and *** the isothermal relaxation process,clusters with coordination numbers 9 and 10 have longer lifetimes,suggesting that the escape of slow Si atoms from their cages is more *** findings mentioned above hold significant implications for understanding the caged dynamics.

关键词： caged dynamics Pd_(82)Si_(18) amorphous alloy fast and slow atoms clusters lifetime

Coercivity mechanism of high-performance anisotropic heterostructure SmCo5 magnets

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Journal of Rare Earths 2024年第10期42卷 1882-1888页

作者： Yuan Teng Yuqing Li Weiqiang Liu Xiaochang Xu Zhanjia Wang Jianjun Yang Dongtao Zhang Hongguo Zhang Qingmei Lu Qiong Wu Weixing Xia Ming Yue Faculty of materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of Technology school of mechanical and electrical engineering Henan Institute of Science and Technology school of mechanical engineering Anyang Institute of Technology Key Laboratory of Magnetic materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of Sciences

Due to its large magnetocrystalline anisotropy field and high Curie temperature,SmCo-based magnets are irreplaceable in high-temperature applications,The hot-deformed SmCo-based magnets are especially attractive for their excellent corrosion resistance,making them more suitable for harsh ***,it is still challenging for hot-deformed SmCo-based magnets to obtain high magnetization and high coercivity ***,it is necessary to analyze the relationship between its microstructure and magnetic properties and explore its magnetic hardening mechanism to guide the further improvement of magnetic *** this paper,the anisotropic heterostructure SmCo5magnet was prepared by combining large height-reduction and introducing a nano-grained Smrich *** c-axis texture,（BH）m of 16.1 MGOe,and Hciof 9.6 kOe were obtained via the heterostructure with SmCo5micron-grain and Sm-rich nano-scale *** magnetic domain observation and technical magnetization analysis demonstrate that the coe rcivity mechanism is dominated by *** results also show that the smooth and Sm-rich precipitated grain boundary provides weak pinning *** provides a reference for the development of high-pe rformance nanocrystalline SmCo5magnets.

关键词： Permanent magnet Heterostructure Rare earths Coercivity mechanism Hot-deformed SmCo magnet