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Role of the inter-pass cooling rate in recrystallization behaviors of Ni-based superalloy during interrupted hot compression

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Chinese Journal of Aeronautics 2019年第5期32卷 1314-1330页

作者： Xin ZHANG hongwei li Mei ZHAN Siliang YAN Ning ZHANG State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University School of Material Science and Engineering Hefei University of Technology

The microstructural evolution of a Ni-based superalloy under interrupted hot compressive deformation with different cooling rates in the inter-pass stage is investigated. It is found that metadynamic recrystallization(MDRX) in the inter-pass stage is more sensitive to the accumulated strain than the deformation temperature which is above the recrystallization temperature. The variations of both the grain distribution and the texture intensity caused by MDRX during the interpass stage result in variations of the yield stress(YS) and the work hardening(WH) rate in each stage. Results also show that the MDRX process in the inter-pass stage has a considerable influence on the final microstructure of three-pass compression. The final grain distribution is more uniform,and the compression texture gradually transforms into recrystallization texture with an increasing degree of MDRX. In order to predict the MDRX fraction in the inter-pass cooling stage, a modified kinetic equation is established, which can reasonably predict the MDRX behavior under multi-pass compression with different conditions in the inter-pass stage. Meanwhile, the influence of the interpass cooling stage on the mechanism of dynamic recrystallization(DRX) is studied. It is universally acknowledged that the discontinuous dynamic recrystallization(DDRX) process is the major deformation mechanism for the Ni-based superalloy. However, the continuous dynamic recrystallization(CDRX) process is promoted in the compression stage with a decrease of the cooling rate in each inter-pass stage.

关键词： Cooling rate Hot compression test Kinetic equation Ni-based superalloy Recrystallization

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分布电容对引信共线装定系统信息传输特性的影响及其优化

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兵工学报 2024年第1期45卷 319-327页

作者：李昊李豪杰原红伟岳中豪马海涛南京理工大学机械工程学院江苏南京210094 中国晋西工业集团山西太原030051 淮海工业集团有限公司山西长治046012

针对引信共线装定过程中分布电容影响装定可靠性的问题,建立基于装定器模块、能量与信息传输模块、引信电路模块的等效电路模型。分别研究在装定输出信号为高电平时和低电平时两种情况下,分布电容对共线装定系统信息传输特性的影响。得... 详细信息

针对引信共线装定过程中分布电容影响装定可靠性的问题,建立基于装定器模块、能量与信息传输模块、引信电路模块的等效电路模型。分别研究在装定输出信号为高电平时和低电平时两种情况下,分布电容对共线装定系统信息传输特性的影响。得出高电平时分布电容对共线装定系统影响较小的结论,并推导低电平时引信识别到的接收信号的低电平脉宽与分布电容的关系式。提出两种优化方法,一种利用二极管屏蔽外部因素如并入电缆引入的电容;另一种利用并联一个阻值较小电阻的方法来降低系统的时间常数,从而提高引信识别到的低电平脉宽,提高装定可靠性。经仿真和实验验证,两种方法均提高了引信识别接收信号的可靠性。

关键词：引信装定系统分布电容可靠性

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A new quantitative relation between deformation textures and corresponding mechanical properties of FCC metals

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Chinese Science Bulletin 2014年第10期59卷 1049-1056页

作者： hongwei li Shanshan Chen He Yang State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Quantitative analysis of deformation-induced textures and texture-induced mechanical properties is an important issue for optimal design and control of plastic forming of metals.Deformation-induced textures were predicted through the crystal plasticity finite-element method(CPFEM)in this study,and varying deformation modes,including uniaxial compression,uniaxial tension,simple shear,and plane-strain compression,were considered.The predicted textures were proven by experiments.Then,a theoretical model was proposed to build the quantitative relation between textures and the corresponding mechanical properties.This model takes into account the effects of grain’s orientation,grain’s interaction,and the property in the level of single grain.It captures the macroscopic anisotropy owing to textures and microscopic anisotropy owing to crystallographic structures.By applying this model,the macroscopic stress responses of grains’aggregate with varying textures were calculated according to grain’s orientations and the intrinsic properties of the single crystal along[100]and[111]crystallographic directions.The theoretical model is proven to have high efficiency and acceptable accuracy in the prediction of texture-induced mechanical properties comparing with CPFEM model.

关键词： Quantitative relation Deformationtexture Mechanical property Crystal plasticity Anisotropy

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高纯度横波蝶形线圈电磁超声换能器优化设计

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电工技术学报 2024年第11期39卷 3270-3279页

作者：董明李航辉马宏伟陈渊曹现刚西安科技大学机械工程学院西安710054 西安科技大学陕西省矿山机电装备智能检测与控制重点实验室西安710054

蝶形线圈电磁超声换能器(EMAT)能够在铝块中同时激发出超声横波和纵波,接收信号中存在横波反射回波和纵波反射回波,纵波回波会影响缺陷检测的准确性。该文设计了一种变尺寸蝶形线圈EMAT,通过改变线圈不同位置导线的宽度与间距,改变不同... 详细信息

蝶形线圈电磁超声换能器(EMAT)能够在铝块中同时激发出超声横波和纵波,接收信号中存在横波反射回波和纵波反射回波,纵波回波会影响缺陷检测的准确性。该文设计了一种变尺寸蝶形线圈EMAT,通过改变线圈不同位置导线的宽度与间距,改变不同位置的换能效率,以实现横波的增强和纵波的抑制。首先,考虑永磁体的空间磁场分布,分析蝶形线圈EMAT不同位置导线所受洛伦兹力与激发超声波类型的关系,结合有限元声场云图,得到EMAT接收信号中存在多个回波的原因;其次,研究线圈参数对换能效率和横波纵波幅值比的影响规律,利用有限元仿真确定变尺寸EMAT的设计参数;最后,制备常规与变尺寸蝶形线圈EMAT,采集无缺陷铝合金试块的回波,结果表明,当永磁体直径与线圈中心宽度比为1.92时,纵波幅值削弱了66.1%,横波幅值增大了36.3%,横纵波幅值比从5.8升至23.1。该文设计的变尺寸蝶形线圈EMAT实现了对纵波的削弱和横波的增强,提升了横波电磁超声内部缺陷检测的可靠性。

关键词：横波电磁超声换能器高纯度横波变尺寸蝶形线圈缺陷检测

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Establishment and characterization of new wheat-Thinopyrum ponticum addition and translocation lines with resistance to Ug99 races

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Journal of Genetics and Genomics 2016年第9期43卷 573-575页

作者： hongwei li Qi Zheng Zacharias A.Pretorius Bin li Dingzhong Tang Zhensheng li State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Department of Plant Sciences University of the Free State China-Africa Center for Research and Education Chinese Academy of Sciences

Ug99, also designated as TFKSK, is a race of Puccinia graminis Pers.：Pers f. sp. tn＇tici Eriks. and E. Henn （Pgt） with broad virulence to wheat. It is the first known Pgt race possessing virulence to Sr31, a stem rust resistance （Sr） gene deployed in wheat varieties world- wide （Singh et al., 2011 ）. Since the first detection of TFKSK in 1998, a total of 13 Ug99 variants have been identified in several African countries.

关键词： Th Establishment and characterization of new wheat-Thinopyrum ponticum addition and translocation lines with resistance to Ug99 races GISH FISH line

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以新质生产力赋能农业生态产品价值实现

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学术前沿 2024年第10期 63-70页

作者：李宏伟张二进中央党校(国家行政学院)社会和生态文明教研部

新质生产力是培育和形成战略性新兴产业和未来产业的逻辑起点与落脚点。农业生态产品价值实现是乡村全面振兴,实现城乡共同富裕的重要任务。农业领域新质生产力与农业生态产品价值实现在理念转变和产业发展上高度耦合,应以农业领域新质... 详细信息

新质生产力是培育和形成战略性新兴产业和未来产业的逻辑起点与落脚点。农业生态产品价值实现是乡村全面振兴,实现城乡共同富裕的重要任务。农业领域新质生产力与农业生态产品价值实现在理念转变和产业发展上高度耦合,应以农业领域新质生产力的全要素生产率大幅提升赋能农业生态产品价值的实现,形成包含价值链、政策链、创新链、产业链、人才链的“五链融合”作用机制。其实现路径包括:统筹施策补齐短板,推动政策协同;深化农业科技研究,增强创新能力;优化生态农业结构,提升产品品质;创新人才培养模式,优化人才队伍。

关键词：新质生产力农业生态产品机制路径

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Genomic basis of selective breeding from the closest wild relative of large-fruited tomato

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Horticulture Research 2023年第8期10卷 254-264页

作者： Junwei Yang Yun liu Bin liang Qinqin Yang Xuecheng li Jiacai Chen hongwei li Yaqing Lyu Tao lin State Key Laborary of Agrobiotechnology Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable CropsCollege of HorticultureChina Agricultural UniversityBeijing 100193China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen518124China.

The long and intricate domestication history of the tomato(Solanum lycopersicum)includes selection sweeps that have not been fully explored,and these sweeps show significant evolutionary trajectories of domestication traits.Using three distinct selection strategies,we represented comprehensive selected sweeps from 53 Solanum pimpinellifolium(PIM)and 166 S.lycopersicum(BIG)accessions,which are defined as pseudo-domestication in this study.We identified 390 potential selection sweeps,some of which had a significant impact on fruit-related traits and were crucial to the pseudo-domestication process.During tomato pseudo-domestication,we discovered a minor–effect allele of the SlLEA gene related to fruit weight(FW),as well as the major haplotypes of fw2.2/cell number regulator(CNR),fw3.2/SlKLUH,and fw11.3/cell size regulator(CSR)in cultivars.Furthermore,18 loci were found to be significantly associated with FW and six fruit-related agronomic traits in genome-wide association studies.By examining population differentiation,we identified the causative variation underlying the divergence of fruit flavonoids across the large-fruited tomatoes and validated BRI1-EMS-SUPPRESSOR 1.2(SlBES1.2),a gene that may affect flavonoid content by modulating the MYB12 expression profile.Our results provide new research routes for the genetic basis of fruit traits and excellent genomic resources for tomato genomics-assisted breeding.

关键词： breeding cultivar traits

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Regional crustal deformation characteristic before 2016 Yuncheng M4.4 earthquake swarm based on CMONOC continuous GPS data

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Geodesy and Geodynamics 2016年第6期7卷 459-464页

作者： Ruichun li hongwei li Shunda Yang Earthqualte Administration of Shanxi Province Taiyuan 030021China Taiyuan University of Technology Taiyuan 030024China Continental Rift Valley Dynamics State Observatory of Taiyuan Taiyuan 030021China Wutai Earthquake Science and Technology Center Xinzhou 034000China

To further study regional deformation characteristic in the southeast margin of Ordos Block during the period between the Alanshan M5.8 and Yuncheng M4.4 earthquake swarm, we analyze continuous GPS sites around the study area. The time-varying strain parameters removed a linear trend deviated from the background state in varying degrees since April, 2015, and began to turn back at the end of the year 2015, meanwhile, the maximum extension strain and shear strain have the bigger variation relative to others. The GPS measurement also shows that the eastward displacement rate of the stations decreases during 2015-2016 in varying degrees compared to 2011-2015, and the variation is closely related to its geologic structural location. The differential movement between the stations is converted into regional strain accumulation due to the fault locking. Further- more, during 2015-2016, the maximum extension rate oriented at near NS direction obviously increased, and the maximum contraction strain direction is changed from NW to EW direction, which contributes to strengthen extension and shear strain of the NE- striking faults, it＇s consistent with the regional background strain state of Shanxi seismic zone, this may be an important contributor to occurrence of M4.4 earthquake swarm in Yuncheng basin.

关键词： Yuncheng M4.4 earthquake swarmTime-varying strainRobust least squares fitRegional deformation characteristic

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Molecular Cytogenetic Characterization and Stem Rust Resistance of Five Wheat-Thinopyrum ponticum Partial Amphiploids

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Journal of Genetics and Genomics 2014年第11期41卷 591-599页

作者： Qi Zheng Zhenling Lv Zhixia Niu Bin li hongwei li Steven S.Xu Fangpu Han Zhensheng li State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences United States Department of Agriculture Agricultural Research ServiceCereal Crops Research Unit

Partial amphiploids created by crossing common wheat （Triticum aestivum L.） and Thinopyrum ponticum （Podp.） Barkworth ＆ D. R. Dewey are important intermediates in wheat breeding because of their resistance to major wheat diseases. In this study, we examined the chromosome compositions of five Xiaoyan-series wheat-Th, ponticum partial amphiploids （Xiaoyan 68, Xiaoyan 693, Xiaoyan 784, Xiaoyan 7430, and Xiaoyan 7631） using GISH, multicolor-GISH, and multicolor-FISH. We found several chromosome changes in these lines. For example, wheat chromosomes 1B and 2B were added in Xiaoyan 68 and Xiaoyan 7430, respectively, while wheat chromosome 6B was eliminated from Xiaoyan 693 and Xiaoyan 7631. Chromosome rearrangements were also detected in these amphiploids, including an interspecific translocation involving chromosome 4D and some intergenomic translocations, such as A--B and A--D translocations, among wheat genomes. Analysis of the Th. ponticum chromosomes in the amphiploids showed that some lines shared the same alien chromosomes. We also evaluated these partial amphiploids for resistance to nine races of stem rust, including TTKSK （commonly known as Ug99）. Three lines, Xiaoyan 68, Xiaoyan 784, and Xiaoyan 7430, exhibited excellent resistance to all nine races, and could therefore be valuable sources of stem rust resistance in wheat breeding.

关键词： Thinopyrum ponticum Triticum aestivum Partial amphiploid Multicolor-genomic in situ hybridization （mc-GISH） Multicolor-fluorescent insitu hybridization （me-FISH） Stem rust

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The Qitai radio telescope

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 150-161页

作者： Na Wang Qian Xu Jun Ma Zhiyong liu Qi liu Hailong Zhang Xin Pei Maozheng Chen Richard N.Manchester Kejia Lee Xingwu Zheng Hans J.Kärcher Wulin Zhao hongwei li Dongwei li Martin Süss Matthias Reichert Zhongyi Zhu Congsi Wang Mingshuai li Rui li Ning li Guljaina Kazezkhan Wenming Yan Gang Wu Lang Cui Ming Zhang Haitao li Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China Australia Telescope National Facility CSIRO Space and AstronomyEpping 1710Australia Department of Astronomy Peking UniversityBejing 100871China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Dr.Hans Jirgen Karcher Engineering Office Karben 61184Germany Northwest China Research Institute of Electronic Equipment Xi'an 710065China OHB Digital Connect(MT Mechatronics) Mainz 55130Germany Beijing Institute of Architetural Design Beijing 100045China Guangzhou Instiute of Technology Xidian UniversityGuangzhou 510555 China

This study presents a general outline of the Qitai radio telescope(QTT)project.Qitai,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elevation of about 1800 m.The QTT is a fully steerable,Gregorian-type telescope with a standard parabolic main reflector of 110 m diameter.The QTT has adopted an umbrella support,homology-symmetric lightweight design.The main reflector is active so that the deformation caused by gravity can be corrected.The structural design aims to ultimately allow high-sensitivity observations from 150 MHz up to115 GHz.To satisfy the requirements for early scientific goals,the QTTwill be equipped with ultra-wideband receivers and large field-of-view multi-beam receivers.A multi-function signal-processing system based on RFSo C and GPU processor chips will be developed.These will enable the QTT to operate in pulsar,spectral line,continuum and Very Long Baseline Interferometer(VLBI)observing modes.Electromagnetic compatibility(EMC)and radio frequency interference(RFI)control techniques are adopted throughout the system design.The QTT will form a world-class observational platform for the detection of lowfrequency(nano Hertz)gravitational waves through pulsar timing array(PTA)techniques,pulsar surveys,the discovery of binary black-hole systems,and exploring dark matter and the origin of life in the universe.The QTT will also play an important role in improving the Chinese and international VLBI networks,allowing high-sensitivity and high-resolution observations of the nuclei of distant galaxies and gravitational lensing systems.Deep astrometric observations will also contribute to improving the accuracy of the celestial reference frame.Potentially,the QTT will be able to support future space activities such as planetary exploration in the solar system and to contribute to the search for extraterrestrial intelligence.

关键词： radio telescope radio astronomy observation receiver RFI

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