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2024年新疆乌什7.1级地震和中国台湾花莲7.3级地震前的大震长期平静及中国内地强震危险性研究

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地震研究 2025年第1期48卷 32-40页

作者：赵小艳苏有锦孟令媛臧阳云南省地震局云南昆明650224 中国地震台网中心北京100045

对2024年新疆乌什7.1级地震和中国台湾花莲7.3级地震前出现的长期地震平静现象及其平静结束后的地震趋势进行了分析,进而对中国内地当前仍存在的2个大震长期地震平静区域及其危险性进行了分析和讨论。结果表明:①乌什7.1级地震结束了天... 详细信息

对2024年新疆乌什7.1级地震和中国台湾花莲7.3级地震前出现的长期地震平静现象及其平静结束后的地震趋势进行了分析,进而对中国内地当前仍存在的2个大震长期地震平静区域及其危险性进行了分析和讨论。结果表明:①乌什7.1级地震结束了天山地震带长达31年的7级以上地震长期平静状态,可能预示着天山地震带将进入一个新的7级以上地震活跃时段;花莲7.3级地震结束了中国台湾地区长达17年的7级以上地震长期平静状态,可能预示着中国台湾地区将进入一个新的7级以上地震活跃时段。②南北地震带南段的云南地区自1996年丽江7.0级地震以来地震平静时间超过28年,南北地震带北段的甘肃-宁夏地区自1954年内蒙古阿拉善盟阿拉善左旗7.0级地震以来地震平静时间已超过70年,这2个区域当前或未来一个时期发生7级以上地震的风险较高,尤其是云南地震地区,应引起特别的关注和研究。

关键词：乌什7.1级地震花莲7.3级地震地震长期平静南北地震带

Characterizations on the instantaneously formed Ni-containing intermetallics in magnesium alloys

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Journal of Magnesium and Alloys 2023年第8期11卷 2991-2998页

作者： Shuhui Lv Qiang Yang Fanzhi meng Jian meng School of Materials Science and Engineering Changchun University of Science and Technology 130022PR China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022PR China

Instantaneous reactions of Al,Mn,Zn,Zr and Y with Ni by mixing the prepared Mg-8Al-0.4Mn,Mg-6Zn-2Y-0.5Zr and Mg-0.6Ni melts were investigated in this work to reveal the underlying mechanisms of their effects on the removal of Ni *** results indicate three Ni-containing intermetallics,namely Al_(4)NiY,Al_(4)Ni(Y,Zr)and Al_(31)Ni_(2)Mn_(6).The former two phases present lath-like and have a relatively larger size(>20μm in length)than the latest one which is granular with the diameter of∼120 *** illustrates that Al and Y(/Zr)can efficiently remove Ni by forming Al_(4)NiY or Al_(4)Ni(Y,Zr)which would precipitate to the bottom of the ***,adding Y into Mg-Al based alloys can simultaneously remove Fe and Ni,which contributes their excellent corrosion ***,this paper proposes two methods helped to efficiently remove Ni for both Mg-Al based alloys and Al-free Mg alloys,and both of them are also benefit to improve alloys’strength.

关键词： Magnesium alloys Intermetallics Nickel Transmission electron microscopy(TEM) Impurity

A compressing and saving method for structured grid data based on block construction

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Chinese Journal of Aeronautics 2022年第6期35卷 146-155页

作者： Yan SUN Ying ZHAO Dehong meng meng JIANG State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China

The increasing grid data in CFD simulation has brought some new difficulties and challenges,such as high storage cost,low transmission *** order to overcome these problems,a novel method for compressing and saving the structured grid are *** the present method,the geometric coordinates of the six logical domains of one grid block is saved instead of all grid vertex coordinates to reduce the size of the structured grid file when the grid is *** all grid vertex coordinates are recovered from the compressed data with the use of the transfinite interpolation algorithm when the grid is ***,single-block grid cases with different edge vertexes are tested to investigate the compression *** test results show that a higher compression ratio will be obtained on a larger ***,further theoretical analysis is carried out to investigate the effects of parameters on grid *** analysis on single-block grid compression shows that the compression ratio is proportionate to the cubic root of the number of total *** highest compression ratio of single-block grid is obtained when the numbers of vertexes in three logical directions are *** analysis on multi-block grid compression shows that a higher compression ratio will be obtained when a larger difference of total vertexes number exists among the grid ***,multi-blockgrids of two industrial aircraft configurations are compressed to validate the *** compression results demonstrate that the present method has an excellent ability on structured grid *** a million-vertex structured grid,more than 80 percent disk space can be saved after compression.

关键词： CFD Compression Compression ratio Structured grid Transfinite interpolation

Structural design and modal behaviors analysis of a new swept baffled inflatable wing

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Defence Technology（防务技术） 2023年第6期24卷 382-398页

作者： Nuo Ma Li Liu Fanmin meng Junhui meng School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081PR China

Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and ***,due to the flexible characteristics,aeroelastic behaviors of inflatable wings such as flutter are nonnegligible in *** designing a certain angle between the inflatable beam and the wing span,the structural dynamic and even the aeroelastic performance of the inflatable wing can be effectively *** on the analysis of the mechanical and geometric characteristics of the inflatable structure,a new inflatable wing with sweep arranged inflatable beams is proposed,and the main design variables and methods are *** purpose of investigating the aeroelastic performance of the swept baffled inflatable wing,the modal behaviors by considering the wet mode are *** consideration of the deficiencies of the traditional wet modal analysis method,by introducing the influence on the additional stiffness of flow field,an added massstiffness method is proposed in this paper,and the advantages are verified by ground vibration *** this basis,the effects of baffles sweep angle,pressure,and boundary conditions on the modal parameters and aeroelastic performance of inflatable wing are *** results show that the aeroelastic performance of the inflatable wing can be designed by changing the baffles sweep angle,which is enlightened for the aeroelastic tailoring design on inflatable wings.

关键词： Inflatable wing Structural design Wet mode Flutter analysis

Property T and strong property T for unital*-homomorphisms

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Frontiers of Mathematics in China 2020年第2期15卷 385-398页

作者： Qing meng School of Mathematical Sciences Qufu Normal UniversityQufu 273165China

We introduce and study property T and strong property T for unital*-homomorphisms between two unital C^*-*** also consider the relations between property T and invariant subspaces for some canonical unital^-*** a corollary,we show that when G is a discrete group,G is finite if and only if G is amenable and the inclusion map i:Cr^*(G)→B(l^2(G))has property *** also give some new equivalent forms of property T for countable discrete groups and strong property T for unital C^*-algebras.

关键词： Unital*-homomorphism unital C^*-algebra *-bimodule property T strong property T

Insight into deformation allocation in the multi-pass roll forming of a double-walled brazed tube

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Advances in Manufacturing 2023年第4期11卷 567-586页

作者： meng-meng Liu Yu-Li Liu Heng Li State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an710072People’s Republic of China

Deformation allocation is an important factor that affects 720°curling forming from copper-coated steel strips to double-walled brazed tubes(DWBTs).In this study,four schemes of deformation allocation,considering different weights of the total feed distance,are proposed,and a 3D finite element(FE)model of the multi-pass roll forming process for DWBT is developed and verified to investigate the cross-sectional evolution and deformation *** results show the following.(i)In the 720°curling forming process from the steel strip into double-walled tubes,the curvature of the formed circular arc initially increases and then remains stable with roll forming,and the inner and outer tubes of the DWBT are formed in the third and fifth forming *** forming can eliminate the gap between the double walls and improve the overall roundness.(ii)For different deformation allocations,the cross-sectional profiles of the roll-formed parts exhibit a discrepancy,and the deformation amount varies with the roll-forming *** deformation amount in Scheme three is the maximum,and the cross-sectional profile deviates significantly from the ideal shape and fails to form a DWBT,which indicates that the deformation allocation is unsuitable.(iii)The roundness of the outer tube is better than that of the inner ***,the roundness of the inner tube is the key to restricting the forming accuracy of the *** with Schemes one and two,Scheme four with a linear allocation of the total feed distance exhibits the best roundness,and the deformation allocation is reasonable;i.e.,when the contact points between the rollers and steel strip are in a straight line,the roundness of the DWBT is in good agreement with the ideal condition.

关键词： Double-walled brazed tube(DWBT) Multi-pass roll forming Deformation allocation Cross-sectional profile Roundness

Flex Ethernet Technology and Application in 5G Mobile Transport Network

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China Communications 2021年第2期18卷 250-258页

作者： meng Zhang Research Institute of Telecommunications Transmission(RITT) China Academy of Information Communications Technology(CAICT)MIITBeijing 100191China

With the advent of 5G era,the rise of cloud services,virtual reality/virtual reality(AR/VR),vehicle networking and other technologies has put forward new requirements for the bandwidth and delay of the bearer *** Ethernet technology cannot meet the new requirements very *** Ethernet(FlexE)technology has emerged as the times *** paper introduces the background,standardization process,functional principle,application mode and technical advantages of FlexE technology,and finally analyses its application prospects and shortcomings in 5G mobile transport network.

关键词： Flex Ethernet(FlexE) 5G mobile transport network network slicing

Pretreatment and thiosulfate leaching of refractory gold-bearing arsenosulfide concentrates

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Journal of University of Science and Technology Beijing 2005年第5期12卷 385-389页

作者： Yuqun meng Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

A hydrometallurgical process for refractory gold-bearing arsenosulfide concentrates at ambient temperature and pressure was presented, including fine grinding with intensified alkali-leaching （FGIAL）, enhanced agitation alkali-leaching （EAAL）, thiosulfate leaching and displacement. Experimental results on a refractory gold concentrate showed that the total consumption of NaOH in alkaline leaching is only 41% of those theoretically calculated under the conditions of full oxidization for the same amount of arse- nides and sulfides transformed into arsenates and sulfates, and 72.3% of gold is synchro-dissoluted by thiosulfate self-generated during alkaline leaching. After alkaline leaching, thiosulfate leaching was carried out for 24 h. The dissolution of gold is increased to 91.9% from 4.6% by cyanide without the pretreatment. The displacement of gold by zinc powder in the solution gets to 99.2%. Due to an amount of thiosulfate self-generated during alkaline leaching, the reagent addition in thiosulfate leaching afterwards is lower than the normal.

关键词： refractory gold-bearing arsenosulfide concentrates pretreatment alkaline leaching self-leaching of gold thiosulfate leaching

Summary of research on recommendation system based on serendipity

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The Journal of China Universities of Posts and Telecommunications 2022年第4期29卷 89-105页

作者： meng Wei Wang Liting Lümeng School of Information Science and Technology Beijing Forestry UniversityBeijing 100083China Engineering Research Center for Forestry-oriented Intelligent Information Processing National Forestry and Grassland AdministrationBeijing 100083China

Personalized recommender systems provide various personalized recommendations for different users through the analysis of their respective historical ***,the problem of the“filter bubble”which has to do with over-specialization ***(SRDP),one of the evaluation indicators,can provide users with unexpected and useful recommendations,and help to successfully mitigate the filter bubble problem,and enhance users’satisfaction levels and provide them with diverse *** SRDP is highly subjective and challenging to study,only a few studies have focused on it in recent *** this study,the research results on SRDP were summarized,the various definitions of SRDP and its applications were discussed,the specific SRDP calculation process from qualitative to quantitative perspectives was presented,the challenges and the development directions were outlined to provide a framework for further research.

关键词： serendipity recommended algorithm recommended diversity filter bubbles evaluation indicators