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Microstructure and mechanical property of Sn–Ag–Cu solder material

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Rare Metals 2017年第3期36卷 193-197页

作者： yi-Gang kong Zhi-Gang kong Feng-Min Shi School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Research Laboratory of Electrical Contacts Beijing University of Posts and TelecommunicationsBeijing 100876China Technology Department Jinan No.10 Radio Factory Co.Ltd.Jinan 250100China

Among the lead-free solder materials,Sn-Ag-Cu alloys have many advantages,such as good wetting property,superior interfacial properties and high creep *** this article,the organization and welding performance of Sn-Ag-Cu material were *** surface morphology of the two alloys was observed by stereoscopic microscope and scanning electron microscope （SEM）.Chemical constitution was examined by X-ray energy-dispersive spectroscopy （EDS）.The mechanical properties of Sn-Ag-Cu solder were evaluated systematically compared with those of Sn-Cu *** results show that Sn-Ag-Cu solder based on different solder pads has different welding *** thickness of intermetallic compound （IMC） at the interface increases with aging *** the gold-plated pads,there are a large number of IMC graphic,and in the welding interface,it can reduce the reliability of electrical *** Sn-Ag-Cu solder joints show a superior mechanical property over the traditional Sn-Cu *** number of dimples decreases and that of cavities increases for Sn-Cu0.7 alloy and the fracture surfaces of Sn-Ag3.0-Cu0.5 alloy have many small size dimples which are homogeneously distributed.

关键词： Lead-free solder Organization Weldingperformance Intermetallic compound

TEMPO-Regulated Regio-and Stereoselective Cross-Dihalogenation with Dual Electrophilic X^(+) Reagents

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Chinese Journal of Chemistry 2021年第11期39卷 3004-3010页

作者： yi kong Tongxiang Cao Shifa Zhu Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhouGuangdong510640 China

A TEMPO catalyzed cross-dihalogenation reaction was established via redox-regulation of the otherwise complex system of dual electrophilic X+***,the ICl,BrCl,I_(2) and Br_(2) were generated in-situ,which enabled high regio-or stereoselective access to a myriad of iodochlorination,bromochlorination and homo-dihalogenation products with a wide spectrum of *** its mild conditions and operational simplicity,this method could enable wide applications in organic synthesis,which was exemplified by divergent synthesis of two *** mechanistic investigations via radical clock reaction,pinacol ring expansion and Hammett experiments were conducted,which confirmed the intermediacy of halonium *** addition,a dynamic catalytic model based on the versatile catalytic role of TEMPO was proposed to explain the selective outcomes.

关键词： Halogenation Organocatalysis Electrophilic addition Redox-regulation Alkynes

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基于关系有向图正则化的属性三因子分解模型

郑州大学学报（理学版） 2025年第1期57卷 67-73页

作者：张嘉睿李瑞林孔毅余南南江苏师范大学电气工程及自动化学院江苏徐州221116 中国矿业大学信息与控制工程学院江苏徐州221116 中国矿业大学深地工程智能建造与健康运维全国重点实验室江苏徐州221116

针对零样本图像分类中属性和特征之间映射不全面以及属性空间结构挖掘不充分问题,提出了基于关系有向图正则化的属性三因子分解模型。首先,利用属性矩阵三因子分解实现了属性空间和特征空间的映射;其次,通过权值矩阵构建了属性关系有向... 详细信息

针对零样本图像分类中属性和特征之间映射不全面以及属性空间结构挖掘不充分问题,提出了基于关系有向图正则化的属性三因子分解模型。首先,利用属性矩阵三因子分解实现了属性空间和特征空间的映射;其次,通过权值矩阵构建了属性关系有向图;最后,在属性空间或特征空间计算测试样本和各测试类别的相似性,进而实现图像分类。在aPY和SUN数据集上的实验结果表明,所提模型有效地提高了零样本图像分类精度。

关键词：零样本图像属性三因子分解关系有向图正则化

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Synthesis of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives

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Chinese Chemical Letters 2007年第4期18卷 380-382页

作者： Xue Fei Yang Ling yi kong Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3- methoxy-4hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step. The structures of the new compounds were confirmed by 1H NMR, IR and MS. The structure of compound 14 was further confirmed by single crystal X-ray. Compound 17 showed cytotoxic activity against human lung carcinoma A549.

关键词： 2-Aryl-5-alkyl-7-methoxylbenzo[b]furan Neolignans Synthesis Cytotoxicity

Sebiferone,a New Triterpenoid from Stem Bark of Sapium sebiferum (L.)Roxb.

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Chinese Chemical Letters 2002年第11期13卷 1079-1082页

作者： Run Hui LIU Ling yi kong Department of Natural Medicinal Chemistry China Pharmaceutical UniversityNanjing 210038

From the stem bark of Sapium sebiferum a new triterpenoid, named sebiferone (1), was isolated. The structure of the new compound was elucidated as 3β-acetoxy-D-friedoolen-14-en -1-one-28-oic acid on the basis of spe... 详细信息

关键词： Sapium sebiferum Euphorbiaceae sebiferone.

Labdane Diterpenoids from Coleus forskohlii （Willd.） Briq.

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Journal of Integrative Plant Biology 2006年第4期48卷 478-481页

作者： Ling-Ling Xu Ling-yi kong Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

in order to investigate the active substances of Coleus forskohlii（Wiiid.） Brlq., a new labdane dlterpenold, 12- hydroxy-8,*** acid, together with two 8,13-epoxylabd-14-ene-11-one dlterpenolds, 6-acetyl-1- deoxyforskolln and 6-acetyl-1,9-dldeoxyforskolln, was Isolated on the basis of various chromatographic technlques and spectroscopic methods.

关键词： 6-acetyl-1-deoxyforskolin 6-acetyl-1 ,9-dideoxyforskolin Coleus forskohlii 12-hydroxy-8,13E-labdadien-15-oic acid labdane diterpenoid.

Steroids from the Roots of Asparagus officinalis and Their Cytotoxic Activity

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Journal of Integrative Plant Biology 2008年第6期50卷 717-722页

作者： Xue-Feng Huang Yu-ying Lin Ling-yi kong Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

One new （Sarsasapogenin O） and seven known steroids were isolated from the roots of Asparagus offlcinalis L. Their structures were elucidated on the basis of spectroscopic analysis, including various 2D-NMR techniques, hydrolysis, and by comparison of spectral data of known compounds. These compounds together with nine steroids which were previously isolated from this plant, were tested for cytotoxic activity. Among them, eight compounds displayed significant cytotoxiciUes against human A2780, HO-8910, Eca-109, MGC-803, CNE, LTEP-a-2, KB and mouse L1210 tumor cells.

关键词： Asparagus officinalis cytotoxic activity Sarsasapogenin O steroid

Aerodynamic Modeling and Parameter Estimation from QAR Data of an Airplane Approaching a High-altitude Airport

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Chinese Journal of Aeronautics 2012年第3期25卷 361-371页

作者： WANG Qing WU Kaiyuan ZHANG Tianjiao kong yi'nan QIAN Weiqi State Key Laboratory of Aerodynamics.China Aerodynamics Research and Development Center Mianvang 621000.China Computational Aerodynamics Institute China Aerodynamics Research and Development Center Mianyang 621000 China Seientifie Research Base of Civil Aviation Flight Technology and Safety Guanghan 618307China

Aerodynamic modeling and parameter estimation from quick accesses recorder （QAR） data is an important technical way to analyze the effects of highland weather conditions upon aerodynamic characteristics of airplane. It is also an essential content of flight accident analysis. The related techniques are developed in the present paper, including the geometric method for angle of attack and sideslip angle estimation, the extended Kalman filter associated with modified Bryson-Frazier smoother （EKF-MBF） method for aerodynamic coefficient identification, the radial basis function （RBF） neural network method for aerodynamic mod- eling, and the Delta method for stability/control derivative estimation. As an application example, the QAR data of a civil air- plane approaching a high-altitude airport are processed and the aerodynamic coefficient and derivative estimates are obtained. The estimation results are reasonable, which shows that the developed techniques are feasible. The causes for the distribution of aerodynamic derivative estimates are analyzed. Accordingly, several measures to improve estimation accuracy are put forward.

关键词： civil airplane aerodynamics QAR data aerodynamic modeling aerodynamic parameter estimation flight safety EKF-MBF method neural network

Switching on/off phosphorescent or non-radiative channels by aggregation-induced quantum interference

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Aggregate 2024年第1期5卷 175-184页

作者： yi kong Yu-Chen Wang Xunkun Huang WanZhen Liang yi Zhao Department of Chemistry State Key Laboratory of Physical Chemistry of Solid SurfacesiChEMFujian Provincial Key Laboratory of Theoretical and Computational Chemistryand College of Chemistry and Chemical EngineeringXiamen UniversityXiamenPeople’s Republic of China

Pure organic materials with persistent and efficient room-temperature phosphorescence have recently aroused great research interest due to their vast potential in *** crucial design principle for such materials is to suppress as much as possible the non-radiative decay of the triplet exciton while maintaining a moderate phosphorescent radiative ***,molecular engineering often exhibits similar regulation trends for the two ***,we propose that the quantum interference caused by aggregation can be utilized to control the phosphorescent and non-radiative decay *** systematically analyze various constructive and destructive transition pathways in aggregates with different molecular packing types and establish clear relationships between the luminescence characters and the signs of the singlet and triplet excitonic *** is shown that the decay channels can be flexibly switched on or off by regulating the packing type and excitonic *** importantly,an enhanced phosphorescent decay and a completely suppressed non-radiative decay can be simultaneously realized in the aggregate packed with inversion *** work lays the theoretical foundation for future experimental realization of quantum interference effects in phosphorescence.

关键词： excitonic coupling intersystem crossing organic aggregates organic room temperature phosphorescence quantum interference