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In-situ isothermal aging TEM analysis of a micro Cu/ENIG/Sn solder joint for flexible interconnects

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Journal of Materials Science & Technology 2024年第2期169卷 42-52页

作者： jinhong liu Jianhao Xu Kyung-Wook Paik Peng He Shuye Zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China Department of materials science and engineering KAIST291 Daehak-roYuseong-guDaejeon305-338Republic of Korea

Sn/ENIG has recently been used in flexible interconnects to form a more stable micron-sized metallurgical joint,due to high power capability which causes solder joints to heat up to 200℃.However,Cu_(6)Sn_(5)which is critical for a microelectronic interconnection,will go through a phase transition at temperatures between 186 and 189℃.This research conducted an in-situ TEM study of a micro Cu/ENIG/Sn solder joint under isothermal aging test and proposed a model to illustrate the mechanism of the microstructural *** results showed that part of the Sn solder reacted with Cu diffused from the electrode to formη´-Cu_(6)Sn_(5)during the ultrasonic bonding process,while the rest of Sn was left and enriched in a region in the solder *** the enriched Sn quickly diffused to both sides when the temperature reached 100℃,reacting with the ENIG coating and Cu to form(Ni_(x)Cu_(1-x))_(3)Sn_(4),AuSn_(4),and Cu_(6)Sn_(5)*** entering the heat preservation process,the diffusion of Cu from the electrode to the joint became more intense,resulting in the formation of Cu_(3)*** scallop-type Cu_(6)Sn_(5)and the seahorse-type Cu_(3)Sn constituted a typical two-layered structure in the solder *** importantly,the transition betweenηandη’was captured near the phase transition temperature for Cu_(6)Sn_(5)during both the heating and cooling process,which was accompanied by a volume shifting,and the transition process was further *** research is expected to serve as a reference for the service of micro Cu/ENIG/Sn solder joints in the electronic industry.

关键词： In-situ TEM observation Isothermal aging Micro Cu/ENIG/Sn solder joint Cu_(6)Sn_(5)phase transition

Anion exchange membranes with a semi-interpenetrating polymer network using 1,6-dibromohexane as bifunctional crosslinker

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Chinese Journal of Chemical Engineering 2024年第8期72卷 199-208页

作者： Aijie Li Zhanliang Wang Zhihao Si Lu Lu Peipei Huang jinhong liu Songyuan Yao Peiyong Qin Xinmiao Zhang National Energy R&D Center for Biorefinery College of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing 100029China Paris Curie Engineer School Beijing University of Chemical TechnologyBeijing 100029China Environmental Protection Research Institute Beijing Research Institute of Chemical IndustryBeijing 100000China

An anion exchange membrane(AEM)is generally expected to possess high ion exchange capacity(IEC),low water uptake(WU),and high mechanical strength when applied to electrodialysis *** different types of AEMs,semi-interpenetrating polymer networks(SIPNs)have been suggested for their structural superiorities,i.e.,the tunable local density of ion exchange groups for IEC and the restrained leaching of hygroscopic groups by insolubility for ***,the conventional SIPN AEMs still struggle to balances IEC,WU,and mechanical strength simultaneously,due to the lack of the compact crosslinking *** this work,we proposed a novel SIPN structure of polyvinylidene difluoride/polyvinylimidazole/1,6-dibromohexane(PVDF/PVIm/DBH).On the one hand,DBH with two cationic groups of imidazole groups are introduced to enhance the ion conductivity,which is different from the conventional monofunctional modifier with only one cationic *** the other hand,DBH has the ability to bridge with PVIm,where the mechanical strength of the resulting AEM is increased by the increase of crosslinking *** show that a low WU of 38.1%to 62.6%,high IEC of 2.12—2.22 mmol·g^(-1),and excellent tensile strength of 3.54—12.35 MPa for PVDF/PVIm/DBH membrane are *** work opens a new avenue for achieving the high-quality AEMs.

关键词： Anion exchange membrane Polyvinylidene difluoride Electrodialysis Semi-interpenetrating polymer networks

Eutectic high-entropy alloys and their applications in materials processing engineering:A review

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Journal of Materials Science & Technology 2024年第22期189卷 211-246页

作者： jinhong liu Zihan Li Danyang Lin Zhengxin Tang Xiaoguo Song Peng He Shuye Zhang Hong Bian Wei Fu Yanyu Song State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology WeihaiWeihai 264209China Research Institute of Special Steel Central Iron and Steel Research InstituteBeijing 100081China

Eutectic high-entropy alloys(EHEAs),combining the advantages of both eutectic alloys and high-entropy alloys(HEAs),possess good castability and superior comprehensive mechanical properties which are regarded as a revolutionary material *** this paper,a current study of EHEAs is captured comprehensively for the first time,including basic theory,microstructure and deformation behavior,and alloy *** in-depth analysis of the formation of different microstructures of EHEAs and their mechanical properties is presented,and four methods of designing EHEAs are *** to their unique characteristics,EHEAs show great potential in materials processing *** we give a comprehensive summary of their applications in welding,surface engineering,and additive manufacturing for the first *** them,EHEAs in welding are divided into three sections based on different welding techniques:fusion-based welding,solid-state welding,and diffusion reaction-based welding;EHEAs in surface engineering are separated into two parts:surface modification of bulk EHEAs and EHEA coatings;EHEAs in additive manufacturing are elaborated in two parts:laser powder bed fusion(LPBF)and laser direct energy deposition(LDED).Finally,a summary is given and a future outlook is prospected.

关键词： Eutectic high-entropy alloy(EHEA) Microstructure Properties Alloy design Welding Surface engineering Additive manufacturing

吉林蛟河上地幔岩碎块内熔融微区矿物学及其地质意义

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地学前缘 2020年第5期27卷 48-60页

作者：刘劲鸿吉林省地质矿产勘查开发局吉林长春130061

吉林蛟河地幔岩碎块是被碱性橄榄玄武岩岩浆喷发携带至地壳浅部或地表的。碱性橄榄玄武岩中地幔岩碎块含量40%~55%,局部达60%以上;碎块大小不等,一般直径以5~10cm居多,大者达20~35cm,故定名为地幔岩集块熔岩(岩流)。地幔岩碎块以尖晶石... 详细信息

吉林蛟河地幔岩碎块是被碱性橄榄玄武岩岩浆喷发携带至地壳浅部或地表的。碱性橄榄玄武岩中地幔岩碎块含量40%~55%,局部达60%以上;碎块大小不等,一般直径以5~10cm居多,大者达20~35cm,故定名为地幔岩集块熔岩(岩流)。地幔岩碎块以尖晶石二辉橄榄岩和尖晶石斜辉橄榄岩碎块为主,纯橄榄岩次之,未发现石榴石橄榄岩;胶结物为碱性橄榄玄武岩岩浆。本次研究发现地幔岩内存在丰富的、不同成分和形态的熔融微区。熔融微区类型以其形状可分为滴状、扇状、球状、不规则状、短脉状和环边状,以其特征新生矿物分为OL型、K型、Na+Chl型、PL型、OL+SP型、C+SP型和SP+Chl+Ser型。熔融微区结构为玻基间隐结构或放射状结构;矿物呈骸晶状、中空为玻璃质;残余玻璃脱玻化,产生少量针状和不透明黑色雏晶。熔融微区的形状、结构、物质组成及矿物结晶等特征具有标型性,表征这些熔融体是在上地幔深度保存的幔源岩熔融交代的产物,幔源结晶岩是固相残留。该幔源岩经历强火山喷发使其发生爆炸的地质事件,导致K、Na、Al、Ca易熔组分和H2O、CO2等挥发分开始熔融和气体释放,营造快速固化结晶和淬火的环境。这些少量的熔融物择优占据矿物间隙、裂隙、位错或晶体缺陷处汇聚并熔融交代相邻矿物,不断扩展空间,遂形成滴状等特征形状的"微区"。由于熔融程度不同,产生的熔融物的化学成分和结晶程度也有差异,所代表的初始岩浆性质也不一样,可以是超基性或碱性橄榄玄武质,抑或碧玄岩质岩浆。从检测出的这些信息证实,蛟河地幔岩是被不一致熔融抽取后的地幔残留,即岩石圈地幔。

关键词：吉林蛟河地幔岩集块熔岩熔融微区地幔交代作用浆胞

Structure and ^(57)Fe conversion electron Mssbauer spectroscopy study of Mn-Zn ferrite nanocrystal thin films by electroless plating in aqueous solution

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Chinese Science Bulletin 2008年第3期53卷 321-328页

作者： SUN JianRong WANG XueWen liu jinhong WANG JianBo LI FaShen Institute of Applied Magnetics Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou 730000 China

Mn1-xZnxFe2O4 thin films with various Zn contents and of different thickness were synthesized on glass substrates directly by electroless plating in aqueous solution at 90℃ without heat *** Mn-Zn ferrite films have a single spinel phase structure and well-crystallized columnar grains growing perpendicularly to the *** results of conversion electron 57Fe M?ssbauer spectroscopy(CEMS)indicate that the cation distribution of Mn1-xZnxFe2O4 ferrite nanocrystal thin films fabricated by electroless plating is different from the bulk materials' and a great quantity of Fe3+ ions are still present on A sites for x>*** the Zn content of the films increases,Fe3+ ions in the films transfer from A sites to B sites and the hyperfine magnetic field reduces,suggesting that Zn2+ has strong chemical affinity towards the A *** the other side,with the increase of the thickness of the films,Fe3+ ions,at B sites in the spinel structure,increase and the array of magnetic moments no longer lies in the thin film plane *** x = 0.5,Hc and Ms of Mn1-xZnxFe2O4 thin films show a minimum of 3.7 kA/m and a maximum of 419.6 kA/m,respectively.

关键词：锰-锌铁素体纳米晶薄膜化学镀层光谱学薄膜结构

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基于数字出版的科学交流系统成本收益模型

图书情报知识 2009年第1期26卷 63-68页

作者：刘锦宏武汉理工大学文法学院武汉430070

提出基于数字出版的科学交流系统成本收益模型,分析数字出版机构的成本与收益构成,指出只有数字出版机构的利润所得在科学交流各环节共同认可的范围内,科学信息才能更加方便、快捷地传播。

关键词：数字出版科学交流成本收益模型

控制权、现金流权与公司绩效——基于中国民营上市公司的分析

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财经科学 2009年第5期 64-71页

作者：刘锦红四川大学工商管理学院

对所有权结构与公司绩效问题的研究,国内外学者的结论并没有达成统一。本文通过对经典理论模型的扩展和推导,建立了控制权、现金流权与公司绩效之间的关系假设,然后以沪深两市中2004—2007年的147家民营上市公司为样本,采用面板数据的... 详细信息

对所有权结构与公司绩效问题的研究,国内外学者的结论并没有达成统一。本文通过对经典理论模型的扩展和推导,建立了控制权、现金流权与公司绩效之间的关系假设,然后以沪深两市中2004—2007年的147家民营上市公司为样本,采用面板数据的分析方法,从最终控制人的角度考察了所有权结构与公司绩效之间的关系。本文发现,最终控制人的控制权比例与公司绩效负相关;最终控制人的所有权(现金流权)比例与公司绩效负相关;最终控制人的控制权与所有权的偏离程度与公司绩效负相关。这一结论说明,现阶段我国民营上市公司中所有权结构尚不合理,公司内部治理机制尚不健全,最终控制人可能采用"掠夺式分红"、金字塔式控股等方式侵占中小股东的利益,进而损害企业价值,造成公司绩效偏低。

关键词：控制权现金流权公司绩效民营上市公司

Advances in the study of the biological function of Daxx

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Advances in the study of the biological function of Daxx

第11届全国脂质与脂蛋白学术会议

作者： jinhong liu GuoZuo Xiong DuanFang Liao Qinhui Tuo Learning Key Laboratory for Pharmacoproteomics School of Life Science and TechnologyUniversity of South China Department of General Surgery The Second Affiliated Hospital in University of South China Department of Traditional Chinese Diagnotics School of PharmacyHunan University of Chinese Medicine

Death domain-associated protein(Daxx) was originally identified as a protein that specifically binds to the death domain of the transmembrane death receptor FAS(also called CD95) in the cytoplasm and potentiates FAS-induced *** of Daxx enhances Fas-mediated apoptosis and activates the Jun N-terminal kinase(JNK) *** was found in the nuclears where it localizes to promyelocytic leukaemia(PML) oncogenic domains(PODs).As a highly conserved nuclear protein,Daxx plays a important role in proapoptosis,antiapoptosis, transcriptional *** article reviews the latest advances in the study on biological function of Daxx.

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钢筋非均匀锈蚀及剩余截面积分布模型

华中科技大学学报（自然科学版） 2021年第11期49卷 83-88页

作者：刘晋宏罗小勇肖烨中南大学土木工程学院湖南长沙410075

为研究钢筋锈损剩余截面积的随机性,对钢筋混凝土板进行半浸泡通电加速锈蚀试验以获取不同锈蚀率的钢筋,由三维激光扫描获得钢筋试件的三维几何模型和剩余截面积数据,采用正态分布、对数正态分布、韦布尔分布和耿贝尔分布模型对剩余截... 详细信息

为研究钢筋锈损剩余截面积的随机性,对钢筋混凝土板进行半浸泡通电加速锈蚀试验以获取不同锈蚀率的钢筋,由三维激光扫描获得钢筋试件的三维几何模型和剩余截面积数据,采用正态分布、对数正态分布、韦布尔分布和耿贝尔分布模型对剩余截面积的概率分布进行量化,比较其拟合优度,并基于拟合的剩余截面积分布估算锈蚀钢筋变形.研究结果表明:平均锈蚀程度越高,钢筋锈蚀越不均匀,最小截面越薄弱;未锈蚀钢筋剩余截面积分布为单峰对称型,随锈蚀率增大其逐渐变为左偏分布,当平均锈蚀率大于20%时,部分试件的剩余截面积为多峰分布;对平均锈蚀率不大于20%的钢筋,韦布尔分布模型对其剩余截面积概率分布拟合效果最佳,可用于计算锈蚀钢筋剩余变形;对平均锈蚀率大于20%的钢筋,单峰分布模型拟合效果较差.

关键词：锈蚀钢筋非均匀锈蚀三维激光扫描剩余截面积概率分布