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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 113-126页

作者： Wen-Sheng Xu Xiao-Peng Yang Wen-Zheng Zhang Key Laboratory of Advanced materials (MOE) School of Materials Science and Engineering Tsinghua University Beijing 100084 China Oxford Instruments Beijing Office Beijing 100085 China

A calculation method based on a combination of Dg parallelism rule, good matching site（GMS） analysis, CSL/DSCL（coincidence site lattice/displacement shift complete lattice） and the O-lattice theory has been applied to interpret the observation of the habit plane（HP） of the d precipitates and the linear defects in the HP in an inconel 718 superalloy. The small scattering in the HP orientation around an ideal rational plane is interpreted by the existence of a mixture of two types of steps with different heights and inclinations. These steps play a significant role to enhance the degree of matching in the HP. They are associated with secondary dislocations, with Burgers vectors of 1/6 （1 1 2）y/1/3（0 0 1）, and with a direction parallel to a near-invariant line along （110）y. The spacing of the secondary dislocations projected on the terrace plane is around 6.3 nm. The calculated dislocation structure is in good agreement with the observation.

关键词： Good matching site Dislocation Orientation relationship Interfacial structure Coincident site lattice

The role of strain in oxygen evolution reaction

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Journal of Energy Chemistry 2024年第6期93卷 322-344,I0009页

作者： Zihang Feng Chuanlin Dai Zhe Zhang Xuefei Lei Wenning Mu Rui Guo Xuanwen Liu Junhua You School of materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina School of materials Science and Technology Shenyang University of TechnologyShenyang 110870LiaoningChina

The oxygen evolution reaction(OER)is a crucial step in metal-air batteries and water splitting technologies,playing a significant role in the efficiency and achievable heights of these two ***,the OER is a four-step,four-electron reaction,and its slow kinetics result in high overpotentials,posing a *** address this issue,numerous strategies involving modified catalysts have been proposed and proven to be highly *** these strategies,the introduction of strain has been widely reported because it is generally believed to effectively regulate the electronic structure of metal sites and alter the adsorption energy of catalyst surfaces with reaction ***,strain has many other effects that are not well known,making it an important yet unexplored *** on this,this review provides a detailed introduction to the various roles of strain in *** better explain these roles,the review also presents the definition of strain and elucidates the potential mechanisms of strain in OER based on the d-band center theory and adsorption volcano ***,the review showcases various ways of introducing strain in OER through examples reported in the latest literature,aiming to provide a comprehensive perspective for the development of strain ***,the review analyzes the appropriate proportion of strain introduction,compares compressive and tensile strain,and examines the impact of strain on *** the review offers prospects for future research directions in this emerging field.

关键词： Oxygen evolution reaction Strain generation Tensile strain Compressive strain Strain mechanism Strain effects

Resolution Enhancement in Ultrasonic TOFD Imaging by Combining Sparse Deconvolution and Synthetic Aperture Focusing Technique(Sparse-SAFT)

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 141-149页

作者： Xu Sun Li Lin Shijie Jin School of materials Science and Engineering Dalian University of TechnologyDalianChina

The shallow subsurface defects are difficult to be identified and quantified by ultrasonic time-of-flight diffraction(TOFD)due to the low resolution induced by pulse width and beam *** this paper,Sparse-SAFT is proposed to improve the time resolution and lateral resolution in TOFD imaging by combining sparse deconvolution and synthetic aperture focusing technique(SAFT).The mathematical model in the frequency domain is established based on the l1 and l2 norm constraints,and the optimization problem is solved for enhancing time *** this basis,SAFT is employed to improve lateral resolution by delay-and-sum *** simulated and experimental results indicate that the lateral wave and tip-diffracted waves can be decoupled with *** shallow subsurface defects with a height of 3.0 mm at the depth of 3.0 mm were detected quantitatively,and the relative measurement errors of flaw heights and depths were no more than 10.3%.Compared to conventional SAFT,the time resolution and lateral resolution are enhanced by 72.5 and 56%with Sparse-SAFT,***,the proposed method is also suitable for improving resolution to detect the defects beyond dead zone.

关键词： Time resolution Lateral resolution Time-of-flight diffraction(TOFD) Sparse deconvolution Synthetic aperture focusing technique(SAFT) Sparse-SAFT

Spin excitations and spin wave gap in the ferromagnetic Weyl semimetal Co3Sn2S2

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 3-9页

作者： Chang Liu JianLei Shen JiaCheng Gao ChangJiang Yi Di Liu Tao Xie Lin Yang Sergey Danilkin GuoChu Deng WenHong Wang ShiLiang Li YouGuo Shi HongMing Weng EnKe Liu HuiQian Luo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100190China Australian Centre for Neutron Scattering Australian Nuclear Science and Technology OrganizationLucas HeightsNSW2234Australia Songshan Lake materials Laboratory Dongguan523808China Physical Science Laboratory Huairou National Comprehensive Science CenterBeijing101407China

We report a comprehensive neutron scattering study on the spin excitations in the magnetic Weyl semimetal Co3Sn2S2 with a quasi-two-dimensional *** in-plane and out-of-plane dispersions of the spin waves were revealed in the ferromagnetic ***,dispersive but damped spin excitations were found in the paramagnetic *** effective exchange interactions were estimated using a semi-classical Heisenberg model to consistently reproduce the experimental TCand spin ***,a full spin wave gap below Eg=2.3 meV was observed at T=4 *** value was considerably larger than the estimated magnetic anisotropy energy(~0.6 meV),and its temperature dependence indicated a significant contribution from the Weyl *** results suggest that Co3Sn2S2 is a three-dimensional correlated system with a large spin stiffness,and the low-energy spin dynamics can interplay with the topological electron states.

关键词： magnetic Weyl semimetal topological materials spin excitations neutron scattering

Numerical Simulation of Urea Based SNCR Process in a Trinal-Sprayed Precalciner

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Journal of Renewable materials 2021年第2期9卷 269-294页

作者： Yu Liu Hongtao Kao College of materials Science and Engineering Nanjing Tech UniversityNanjing211816China

In order to study the combustion characteristics,NOx emission and NH3 slip in a new trinal-sprayed precalciner,the simulations of combustion and aqueous urea solution based selective non-catalytic reduction(SNCR)process were conducted by computational fluid dynamics in this precalciner,the effects of different injection heights,different injection flow rates and stratified injection under different flow rates on SNCR process were *** results showed that the flow field was symmetrically distributed in the precalciner,and the flue gas from the rotary kiln formed the recirculation region on both sides of the cone body,which increased the residence time of the solid *** temperature was mainly between 1100 K and 1250 K in the middle and upper column of the precalciner,which met the demand of the pulverized coal combustion and raw material *** concentration of NO at the outlet of the precalciner was 559 ppm,moreover,different injection heights and different injection flow rates had a strong influence on NOX removal efficiency and NH3 *** aqueous urea solution should be injected at SNCR-1 to prolong the residence time of NH3,and injection flow rate had an optimal flow rate but not the higher the *** the injection flow rate under stratified injection was 0.019 kg/s,which could play a better optimization role on NO removal efficiency on the basic of the injection flow *** consideration of cost effective,a stratified injection with an injection flow rate of 0.019 kg/s and an injection height of 20 m,25 m and 30 m was suggested as a compromise of a satisfactory NOx reduction rates and reasonable NH3 *** this condition,numerical simulation result showed that NOx concentration at the outlet of precalciner was 297.27 mg/Nm3 and NH3 slip was 4.67 mg/Nm3,meeting emission standard.

关键词： Trinal-sprayed precalciner selective non-catalytic reduction aqueous urea solution NOx reduction

Effect of pouring height on the solidified microstructure of AlSi7Mg alloy

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Journal of University of Science and Technology Beijing 2006年第4期13卷 324-328页

作者： Weimin Mao Yuelong Bai Hai Lin materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The effect of different pouring heights and evenly soaking process in the liquidus and solidus range on the solidified microstructure of AlSi7Mg alloy has been studied. The results show that if the pouring temperature is 630 or 650℃ and the pouring height is 40 mm, the microstructure of the solidified melt is not homogeneous and there are many rosette-like primary α-Al grains. But if the pouring height is increased to 400 mm, the solidified microstructure becomes more homogeneous and favorable to obtain spherical primary α-Al grains in the solidified melt. With further being evenly soaked in the liquidus and solidus range for some time, the temperature difference between the melt center and the melt periphery can be controlled within ±2℃ and the primary α-Al grains will evolve into more spherical grains. The theoretical analysis indicates that the higher pouring height promotes the melt flow motion and makes the temperature field in the melt more homogeneous and restrains the large rosette primary α-Al grains. This flow motion can also promote the ripening effect and the primary α-Al grains in the melt are gradually changed into spherical grains. It can be concluded from the experiments that pouring at an appropriate superheat and from a proper height is a good new method for preparing the semisolid slurry of AlSi7Mg alloy, its process control is easy and the preparation cost is lower.

关键词： AlSi7Mg alloy semisolid pouring height solidification flow motion

An Extensive Study and Review of Privacy Preservation Models for the Multi-Institutional Data

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Journal of Information Security 2023年第4期14卷 343-365页

作者： Sagarkumar Patel Rachna Patel Ashok Akbari Srinivasa Reddy Mukkala Department of Biometrics LabCorp Drug Development Inc. Somerset USA Department of Biometrics Catalyst Clinical Research LLC Wilmington USA Department of Pharmacy Shree Naranjibhai Lalbhai Patel College of Pharmacy Umrakh Surat India Department of Biostatistics EpisData Sterling Heights USA

The deep learning models hold considerable potential for clinical applications, but there are many challenges to successfully training deep learning models. Large-scale data collection is required, which is frequently only possible through multi-institutional cooperation. Building large central repositories is one strategy for multi-institution studies. However, this is hampered by issues regarding data sharing, including patient privacy, data de-identification, regulation, intellectual property, and data storage. These difficulties have lessened the impracticality of central data storage. In this survey, we will look at 24 research publications that concentrate on machine learning approaches linked to privacy preservation techniques for multi-institutional data, highlighting the multiple shortcomings of the existing methodologies. Researching different approaches will be made simpler in this case based on a number of factors, such as performance measures, year of publication and journals, achievements of the strategies in numerical assessments, and other factors. A technique analysis that considers the benefits and drawbacks of the strategies is additionally provided. The article also looks at some potential areas for future research as well as the challenges associated with increasing the accuracy of privacy protection techniques. The comparative evaluation of the approaches offers a thorough justification for the research’s purpose.

关键词： Privacy Preservation Models Multi Institutional Data Bio Technologies Clinical Trial and Pharmaceutical Industry

Plasmon reflection reveals local electronic properties of natural graphene wrinkles

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Chinese Physics B 2019年第11期28卷 74-78页

作者： Runkun Chen Cui Yang Yuping Jia Liwei Guo Jianing Chen Beijing National Laboratory for Optical Physics Institute of PhysicsChinese Academy of SciencesUniversity of Chinese Academy of SciencesBeijing 100190China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesJilin 130033China Research and development Center for Functional Crystals Laboratory of Advanced Materials and Electron MicroscopyBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100190China Songshan Lake materials Laboratory Dongguan 523808China

We systematically studied surface plasmons reflection by graphene wrinkles with different heights on SiC *** with numerical simulation, we found that the geometry corrugation of a few nanometer height wrinkle alone does not causes a reflection of graphene plasmons. Instead, the separated wrinkle from substrate exhibits a nonlinear spatial Fermi energy distribution along the wrinkle, which acts as a heterojunction. Therefor a higher graphene wrinkle induces a stronger damped region when propagating graphene surface plasmons encounter the wrinkle and get reflected.

关键词： graphene plasmons wrinkle reflection electronics

Machine learning prediction of activation energy in cubic Li-argyrodites with hierarchically encoding crystal structure-based(HECS)descriptors

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Science Bulletin 2021年第14期66卷 1401-1408,M0003页

作者： Qian Zhao Maxim Avdeev Liquan Chen Siqi Shi materials Genome Institute Shanghai UniversityShanghai 200444China Australian Nuclear Science and Technology Organization New Illawarra RdLucas HeightsNSW 2234Australia School of Chemistry The University of SydneySydney 2006Australia Key Laboratory for Renewable Energy Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of materials Science and Engineering Shanghai UniversityShanghai 200444China

Rational design of solid-state electrolytes(SSEs)with high ionic conductivity and low activation energy(Ea)is vital for all solid-state *** learning(ML)techniques have recently been successful in predicting Li^(+) conduction property in SSEs with various descriptors and accelerating the development of *** this work,we extend the previous efforts and introduce a framework of ML prediction for E_(a) in SSEs with hierarchically encoding crystal structure-based(HECS)*** cubic Li-argyrodites as an example,an Ea prediction model is developed to the coefficient of determination(R^(2))and rootmean-square error(RMSE)values of 0.887 and 0.02 eV for training dataset,and 0.820 and 0.02 eV for test dataset,respectively by partial least squares(PLS)analysis,proving the prediction power of *** variable importance in projection(VIP)scores demonstrate the combined effects of the global and local Li^(+) conduction environments,especially the anion size and the resultant structural changes associated with anion site *** developed E_(a) prediction model directs us to optimize and design new Li-argyrodites with lower Ea,such as Li_(6–x)PS_(5–x)Cl_(1+x)(materials.

关键词： Solid-state electrolytes(SSEs) Hierarchically encoding crystal structurebased (HECS)descriptors Predicting activation energy Cubic Li-argyrodites Machine learning