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Friction self-piercing riveting(F-SPR)of aluminum alloy to magnesium alloy using a flat die

Journal of Magnesium and Alloys 2022年第5期10卷 1207-1219页

作者： bingxin yang Yunwu Ma He Shan Sizhe Niu Yongbing Li Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240PR China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240PR China Joining and Welding Research Institute Osaka UniversityOsaka 567-0047Japan

Friction self-piercing riveting(F-SPR)process based on a pip die has been invented to solve the cracking problems in riveting high-strength and low-ductility light metals,such as magnesium alloys,cast aluminum,and 7 series aluminum *** this paper,in order to solve quality issues caused by the misalignment between rivet and pip-die in F-SPR,a flat-die based F-SPR process was proposed and employed to join 1.27 mm-thick AA6061-T6 to 3 mm-thick *** results indicate that a 1.0 mm die distance is effective to avoid rivet upset and insufficient *** the feed rate increases,the heat input in the whole process decreases,resulting in a larger riveting force,which in turn increases both the bottom thickness and interlock ***,solid-state bonding,including Al-Mg intermetallic compounds(IMCs),Al-Mg mechanical mixture,and Al-Fe atom interdiffusion was observed at the joint *** upper Al layer was softened,but the lower Mg layer was hardened,and both sheets exhibited a narrowed affected region with the increase of feed rate,while the rivet hardness shows no obvious *** fracture modes appeared accompanying the variations in lap-shear strength and energy absorption as the feed rate increased from 2 mm/s to 8 mm/***,the F-SPR process using a flat die was compared to those using a pip die and a flat bottom die to show the advantage of flat die on coping with the misalignment problem.

关键词： Friction self-piercing riveting(F-SPR) Flat die Aluminum alloy Magnesium alloy Mechanical joining Solid-state bonding

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Combined strengthening mechanism of solid-state bonding and mechanical interlocking in friction self-piercing riveted AA7075-T6 aluminum alloy joints

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Journal of Materials Science & Technology 2022年第10期105卷 109-121页

作者： Yunwu Ma bingxin yang Shanqing Hu He Shan Peihao Geng Yongbing Li Ninshu Ma Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Joining and Welding Research Institute Osaka UniversityOsaka 567-0047Japan

A recently developed friction self-piercing riveting(F-SPR)technique based on the combination of fric-tion stir processing and riveting has been reported to possess both solid-state bonding and mechanical fastening ***,there is still a lack of quantitative understanding of the hybrid en-hancement mechanism,hindering its engineering *** fill in this gap,the current research investigated the microstructure evolution,microhardness distribution,and miniature-tensile performance of the aluminum alloy AA7075-T6 F-SPR joints by *** accurate numerical simulation model was established to quantitatively evaluate the individual contributions of microstructure,local bonding strength,and macro interlocking to the performance of the joint,which could well explain the experi-mental *** was found that due to the friction stirring of the rivet,solid-state bonding driven by dynamic recrystallization is realized between the trapped aluminum in the rivet cavity and the bottom aluminum *** solid-state bonding zone has 75%yield strength,81%ultimate tensile strength,and 106%elongation compared to the base *** solid-state bonding enables the internal interlock-ing between the trapped aluminum and the rivet to withstand the additional load,which forms a novel dual-interlock fastening mechanism and increases the peak cross-tension force by 14.3%compared to the single-interlock joint.

关键词： Combined strengthening Friction self-piercing riveting Miniature tensile test Solid-state joining Dual-interlocking Numerical simulation

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Fe-N-C core-shell catalysts with single low-spin Fe(Ⅱ)-N_(4)species for oxygen reduction reaction and high-performance proton exchange membrane fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 538-546,I0013页

作者： Yan Wan Linhui Yu bingxin yang Caihong Li Chen Fang Wei Guo Fang-Xing Xiao yangming Lin Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021FujianChina Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002FujianChina College of Materials Science and Engineering Fuzhou UniversityNew CampusMinhou 350108FujianChina College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117FujianChina

Fe-N-doped carbon materials(Fe-N-C)are promising candidates for oxygen reduction reaction(ORR)relative to Pt-based catalysts in proton exchange membrane fuel cells(PEMFCs).However,the intrinsic contributions of Fe-N_(4)moiety with different chemical/spin states(e.g.D1,D2,D3)to ORR are unclear since various states coexist *** the present work,Fe-N-C core-shell nanocatalyst with single lowspin Fe(Ⅱ)-N_(4)species(D1)is synthesized and identified with ex-situ ultralow temperature Mossbauer spectroscopy(T=1.6 K)that could essentially differentiate various Fe-N_(4)states and invisible Fe-O *** quantifying with CO-pulse chemisorption,site density and turnover frequency of Fe-N-C catalysts reach 2.4×10^(-9)site g^(-1)and 23 e site~(-1)s^(-1)during the ORR,***-wave potential(0.915V_(RHE))of the Fe-N-C catalyst is more positive(approximately 54 mV)than that of Pt/***,we observe that the performance of PEMFCs on Fe-N-C almost achieves the 2025 target of the US Department of Energy by demonstrating a current density of 1.037 A cm^(-2)combined with the peak power density of 0,685 W cm^(-2),suggesting the critical role of Fe(Ⅱ)-N_(4)site(D1).After 500 h of running,PEMFCs still deliver a power density of 1.26 W cm^(-2)at 1.0 bar H_(2)-O_(2),An unexpected rate-determining step is figured out by isotopic labelling experiment and theoretical *** work not only offers valuable insights regarding the intrinsic contribution of Fe-N_(4)with a single spin state to alkaline/acidic ORR,but also provides great opportunities for developing high-performance stable PEMFCs.

关键词： Fuel cells Oxygen reduction reaction Non-platinum group metals(PGMs) Isotopic labelling Active site TOF

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Biallelic variants in RBM42 cause a multisystem disorder with neurological,facial,cardiac,and musculoskeletal involvement

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Protein & Cell 2024年第1期15卷 52-68页

作者： Yiyao Chen bingxin yang Xiaoyu Merlin Zhang Songchang Chen Minhui Wang Liya Hu Nina Pan Shuyuan Li Weihui Shi Zhenhua yang Li Wang Yajing Tan Jian Wang Yanlin Wang Qinghe Xing Zhonghua Ma Jinsong Li He-Feng Huang Jinglan Zhang Chenming Xu Institutes of Biomedical Sciences Fudan UniversityShanghai 200032China bstetrics and Gynecology Hospital Institute of Reproduction and DevelopmentFudan UniversityShanghai 200011China Intermational Peace Matermity and Child Health Hospital School of MedicineShanghai Jiao Tong UniversityShanghai 200030China Shanghai Key Laboratory of Embryo Original Diseases Shanghai 200030China State Key Laboratory of Cell Biology Shanghai Key Laboratory of Molecular AndrologyShanghai Institute of Biochemistry and Cell BiologyCAS Center for Excellence in Molecular Cell ScienceUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China State Key Laboratory of Rice Biology the Key Laboratory of Molecular Biology of Crop Pathogens and InsectsInstitute of BiotechnologyZhejiang UniversityHangzhou 310058China Verna and Marrs McLean Department of Biochemistry and Molecular Biology Baylor College of MedicineHoustonTX 77030USA Children's hospital of Fudan University Shanghai 201102China School of Life Science and Technology Shanghai Tech UniversityShanghai 201210China School of Life Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024ZhejiangChina Research Units of Embryo Original Diseases Chinese Academy of Medical Sciences(No.2019RU056)Shanghai 200011China

Here,we report a previously unrecognized syndromic neurodevelopmental disorder associated with biallelic loss-of-function variants in the RBM42 *** patient is a 2-year-old female with severe central nervous system(CNs)abnormalities,hypotonia,hearing loss,congenital heart defects,and dysmorphic facial *** whole-exome sequencing(WEs)reveals that the patient has two compound heterozygous variants,c.304C>T(p.R102*)and c.1312G>A(p.A438T),in the RBM42 gene which encodes an integral component of splicing complex in the RNA-binding motif protein *** p.A438T variant is in the RRM domain which impairs RBM42 pro-tein stability in ***,p.A438T disrupts the interaction of RBM42 with hnRNP K,which is the causa-tive gene for Au-Kline syndrome with overlapping disease characteristics seen in the index *** human R102*or A438T mutant protein failed to fully rescue the growth defects of RBM42 ortholog knockout△FgRbp1 in Fusarium while it was rescued by the wild-type(WT)human RBM42.A mouse model carying Rbm42 compound heterozygous variants,c.280C>T(p.Q94*)and c.1306_1308delinsACA(p.A436T),demonstrated gross fetal develop-mental defects and most of the double mutant animals died by ***-seq data confirmed that Rbm42 was involved in neurological and myocardial functions with an essential role in alternative splicing(As).Overall,we present clinical,genetic,and functional data to demonstrate that defects in RBM42 constitute the underlying etiology of a new neurodevelopmental disease which links the dysregulation of global AS to abnormal embryonic development.

关键词： RBM42 gene RNA-binding protein neurodevelopmental disorder Au-Kline syndrome alternative splicing

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中国首台胶片型航天相机追述——纪念中国第一颗返回式卫星成功返回40周年

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航天返回与遥感 2015年第6期36卷 6-10页

作者：杨秉新北京空间机电研究所北京100094

中国首颗遥感卫星装载一台可见光全景相机,首次实现了从太空摄拍地面目标,使中国成为继美苏后第三个掌握航天相机技术的国家。文章回顾了相机的研制历程,首次披露相机主要任务、方案选择,基本原理、主要参数、成像品质及其评价,最后与... 详细信息

中国首颗遥感卫星装载一台可见光全景相机,首次实现了从太空摄拍地面目标,使中国成为继美苏后第三个掌握航天相机技术的国家。文章回顾了相机的研制历程,首次披露相机主要任务、方案选择,基本原理、主要参数、成像品质及其评价,最后与美国同类相机进行了比较。

关键词：全景相机胶片型相机返回式卫星航天遥感

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一种新的遥感影像清晰度评价方法

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中国空间科学技术 2016年第2期36卷 50-57页

作者：谭伟杨秉新何红艳北京空间机电研究所北京100094

针对传统清晰度评价算法很难准确评价遥感卫星影像清晰度的问题,结合工程应用及遥感影像特点提出了一种新的遥感图像清晰度评价算法——自检测灰度梯度函数清晰度评价算法。把评价过程分为目标区域检测和清晰度特征参量提取,为解决遥感... 详细信息

针对传统清晰度评价算法很难准确评价遥感卫星影像清晰度的问题,结合工程应用及遥感影像特点提出了一种新的遥感图像清晰度评价算法——自检测灰度梯度函数清晰度评价算法。把评价过程分为目标区域检测和清晰度特征参量提取,为解决遥感影像数据量大且景物密度与分布特点各异的问题,首先通过检测算子对一幅遥感影像中各区域进行检测来得到景物丰富且边缘明显的目标区域,然后再对目标区域进行灰度预处理并提取目标区域的边缘灰度梯度来评价清晰度。通过三组不同类型影像对该算法进行验证,分别为遥感相机在轨离焦仿真影像和噪声仿真影像,以及在轨型号遥感卫星影像,对比几种传统典型清晰度评价算法和自检测灰度梯度函数的评价效能,结果表明:文中方法满足遥感影像清晰度评价的基本要求,解决了传统算法无法横向比较不同遥感相机影像及不同大小影像清晰度的问题,是一种适合卫星遥感影像清晰度评价的方法。

关键词：清晰度目标区域特征参量预处理影像评估航天遥感

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线阵CCD相机细分采样成像的像质研究

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光学学报 2000年第10期20卷 1407-1411页

作者：郝云彩杨秉新张国瑞北京空间机电技术研究所北京100076

从理论上推导了线阵 CCD相机间歇细分采样和连续细分采样成像所得到的光电图像调制度和调制传递函数公式 ,并讨论了这两种采样方法对提高动态成像调制传递函数的不同效果 ,分析比较了它们的特点和工程应用的可能性。

关键词：细分采样线阵CCD相机成像像质

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“高分二号”卫星高分辨率相机技术创新及启示

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航天返回与遥感 2015年第4期36卷 10-15页

作者：杨秉新曹东晶北京空间机电研究所北京100190

文章介绍了"高分二号"(GF-2)卫星高分辨率相机的主要参数和特点,并将其主要性能参数与国际上同类相机进行了对比;介绍了GF-2卫星在相机总体方案、星地一体化、隔离微振、精密热控等方面的技术创新;通过全链路分析和仿真等技术手段,将?F/... 详细信息

文章介绍了"高分二号"(GF-2)卫星高分辨率相机的主要参数和特点,并将其主要性能参数与国际上同类相机进行了对比;介绍了GF-2卫星在相机总体方案、星地一体化、隔离微振、精密热控等方面的技术创新;通过全链路分析和仿真等技术手段,将?F/P=1设计理念与调制传递函数补偿技术结合起来,实现了相机的轻小型化,图像品质满足用户的要求。最后,文章给出了从GF-2卫星相机研制中得到的启示。

关键词：技术创新调制传递函数高分辨率相机 “高分二号”卫星航天遥感

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自适应光学在空间光学遥感器上的应用

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高技术通讯 2000年第3期10卷 48-52页

作者：张志伟俞信杨秉新北京理工大学光电工程系北京100081 北京空间机电研究所

阐述了在空间光学遥感器上应用自适应光学技术的必要性 ,介绍了国外的STMT、LDR和Hubble等几种空间光学遥感器应用自适应光学技术的情况 ,论述了轻小型和集成化的星载自适应光学系统的技术现状和发展趋势。进行了星载相机主镜温度变形... 详细信息

阐述了在空间光学遥感器上应用自适应光学技术的必要性 ,介绍了国外的STMT、LDR和Hubble等几种空间光学遥感器应用自适应光学技术的情况 ,论述了轻小型和集成化的星载自适应光学系统的技术现状和发展趋势。进行了星载相机主镜温度变形的自适应光学校正实验 ,改善系数大于 10。这说明 ,对大口径、高分辨率空间相机采用自适应光学技术校正主镜由于温度场变化而产生的变形 ,可以有效地改善波前质量。

关键词：自适应光学微小型化空间光学遥感器

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研发强度、环境不确定性与成本粘性

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财会通讯（下） 2019年第12期 50-54页

作者：杨炳昕陈耿飞上海大学管理学院

现阶段,面对国家经济转型带来的环境不确定性,我国企业亟需激发内部活力,通过加大研发强度等措施,配合国家供给侧改革等政策,实现长期稳定发展的目标。而研发强度的加大可能通过多种机制对成本调整产生影响,导致成本粘性现象加剧。本文... 详细信息

现阶段,面对国家经济转型带来的环境不确定性,我国企业亟需激发内部活力,通过加大研发强度等措施,配合国家供给侧改革等政策,实现长期稳定发展的目标。而研发强度的加大可能通过多种机制对成本调整产生影响,导致成本粘性现象加剧。本文以2008—2017沪深两市A股上市公司为样本对研发强度影响成本粘性的机制进行实证研究,研究结果表明:企业研发强度与成本粘性正相关;环境不确定性加强了企业研发强度对成本粘性的影响,即环境不确定性越大,企业研发强度对成本粘性的促进作用越强;进一步的研究表明,国有产权性质以及债务约束削弱了环境不确定性对研发强度与成本粘性关系的调节作用。

关键词：研发强度环境不确定性成本粘性产权属性债务约束

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