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Design and Application of Indole-Based Allylic Donors for Pd-Catalyzed Decarboxylative Allylation Reactions

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Chinese Journal of Chemistry 2020年第12期38卷 1612-1618页

作者： qing-qing hang Si-Jia Liu Lei Yu Ting-Ting Sun Yu-Chen Zhang Guang-Jian Mei Feng Shi School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116China

of main observation and conclusion A new class of indole-based allylic donors have been designed and developed for palladium-catalyzed decarboxylative *** addition,the first application of these indole-based allylic donors in palladium-catalyzed decarboxylative[3+2]cydoaddition and allylic amination has been achieved by reacting with isocyanates and sulfonyl amines,*** approach represents the first design of indole-based allylic donors,which is helpful for settling the challenge of designing and developing new class of heterocycle-based allylic donors for Pd-catalyzed decarboxylative allylation ***,the application of this new class of allylic donors in cycloadditions and substitutions will add new contents to the research field of decarboxylative allylation.

关键词： palladium catalyzed allyl

基于非协调参数Drucker-Prager模型的预应力节段拼装混凝土桥墩滞回性能研究

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世界地震工程 2018年第1期34卷 138-143页

作者：杜青陈航卿龙邦河北工业大学土木与交通学院天津300401

混凝土的数值计算模型在滞回性能分析中往往比较难收敛,利用有限元软件ADINA提供Drucker-Prager模型的Cap修正屈服准则确立的非协调参数Drucker-Prager模型对预应力节段拼装混凝土桥墩进行数值分析,对预应力节段拼装桥墩在低周往复荷载... 详细信息

混凝土的数值计算模型在滞回性能分析中往往比较难收敛,利用有限元软件ADINA提供Drucker-Prager模型的Cap修正屈服准则确立的非协调参数Drucker-Prager模型对预应力节段拼装混凝土桥墩进行数值分析,对预应力节段拼装桥墩在低周往复荷载作用下的滞回性能进行分析。通过比较采用非协调参数Drucker-Prager模型建立的数值模型计算得到的滞回曲线与试验得到的结果,两者吻合程度较高。基于这一成果可以通过数值模拟的方式获得预应力节段拼装桥墩的滞回曲线与相关数据,可应用于预应力节段拼装桥墩抗震计算和设计。

关键词：节段拼装桥墩非协调参数Drucker—Prager模型滞回曲线

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闽台农业合作与福建农地合理利用探析

生态经济(学术版) 2008年第1期 167-170页

作者：陈洪昭王庆林卿赵航福建师范大学经济学院福建师范大学闽台区域研究中心福建师范大学经济学院福建师范大学闽台区域研究中心福州350007

福建农地资源稀缺,需要合理利用。闽台农业合作在一定程度上提高了福建农地的利用效率,但也存在着短期经营与过度利用的问题,出现了损害农民土地权益的现象。本文通过对此分析后,提出应当从完善农户农地承包经营权、健全农地承包经营权... 详细信息

福建农地资源稀缺,需要合理利用。闽台农业合作在一定程度上提高了福建农地的利用效率,但也存在着短期经营与过度利用的问题,出现了损害农民土地权益的现象。本文通过对此分析后,提出应当从完善农户农地承包经营权、健全农地承包经营权流转市场、稳定台商农地租赁使用权、加强农地监督利用等方面促进合作中农地合理利用。

关键词：农地合理利用闽台农业合作

Graphene Fibers: Advancing Applications in Sensor, Energy Storage and Conversion

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Chinese Journal of Polymer Science 2019年第6期37卷 535-547页

作者： Guan-hang Yu qing Han Liang-Ti Qu Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials Key Laboratory of Cluster Science Ministry of Education School of Chemistry Beijing Institute of Technology

Graphene fibers are a kind of novel carbon fibers assembled by orderly aligned graphene sheets with high flexibility, good conductivity, high thermal conductivity, and low density, which make them possible to be widely used in high-performance and multifunctional compound materials as well as flexible electronic devices. In this review, we summarize the research progress in the synthesis of graphene fibers, and their applications in sensor, energy storage, and energy conversion. Furthermore, the current issues and some prospects for the future trend of graphene fibers are discussed.

关键词： Graphene fibers Assembly Functionalization Sensor Energy storage and conversion

Composite Converter Combined APFC with Switched-capacitor Converter

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 281-291页

作者： qing Fu Yishan Chen Yixing Su Yang hang School of Physics Sun Yat-Sen UniversityGuangzhou 510275China

To reduce switch numbers and voltage stress in semiconductor devices,this paper proposes a novel single-phase converter combined Active Power Factor Correction(APFC)with switched-capacitor *** addition,dynamic voltage regulation and voltage gain are improved by integrating the boost converter and switching capacitor *** interstage bulk capacitor is no longer *** average current control with redistribution of voltage in cells is proposed to obtain voltage lift ability of the switching capacitor cells and maintain a high-power *** study and verify the proposed converter preliminarily,theoretical analysis and simulation are presented in the ***,a 50o W prototype with two different configurations is built for experimental *** proposed converter can reach 95.62%of maximum efficiency,0.99 of power factor,and 3.55%of THD with 600 V output voltage,simultaneously.

关键词： AC-DC converter composite conveter power factor correction switched capacitor

Two-Type Information Fusion Based IP-to-AS Mapping Table Refining

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Journal of Computer Science & Technology 2017年第3期32卷 571-584页

作者： qing Jiang hang-Yu Hu Guang-Min Hu School of Communication and Information Engineering University of Electronic Science and Technology of China Chengdu 611731 China

The Internet topology at the autonomous system （AS） level is of great importance, and traceroute has been known to be a potential tool to obtain a complete AS topology. The original IP-to-AS mapping table maps the IP addresses in traceroute paths to their origin ASes, which may cause false AS links. The existing methods refine the original mapping table based on traceroute-BGP path pairs or alias resolution data. However, the information extracted from either of them is inaccurate and incomplete. In this paper, we present a two-type information fusion based method to refine the original mapping table. We extract four kinds of information from path pair and alias resolution data. Based on these information, we build a candidate AS set for each router. Then we choose the AS that is consistent with the existing information to be the owner AS of each router and map all of the IP addresses on the router to it. We validate the result with the ground truth from PeeringDB and Looking Glass severs. Compared with the existing methods, our method produces a more accurate mapping table. In addition, we discuss the coverage of our method and show that our method is convergent and more robust against the reduction of information or the increase of incorrect information.

关键词： network topology Internet routers BGP traceroute

Analysis of the buoyancy-induced heat transferin a rotating cavity

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航空动力学报 2012年第3期27卷 566-571页

作者： Tian, Shu-qing Xue, hang Gao, Chao Li, Ying Technology Department Aviation Industry Corporation of China Commercial Aircraft Engine Company Limited Shanghai 200241 China Institute of Steam and Gas Turbines Rheinisch-Westfaelische Technische Aachen University Germany Civil Aircraft Marketing and Sales Aviation Industry Corporation of China International Holding Corporation Beijing 100101 China School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China Hekou Oil Production Plant of Shengli Oilfield Sinopec Group Shandong Dongying 257200 China

In order to get a better knowledge of the heat transfer in compressor cavities of aero-engines,the simplified rotating cavity with two-plane discs,a shaft and a cylindrical rim has been investigated numerically and compared with the available *** numerical results in agreement with the available experiments show large-scale *** disk local Nusselt numbers show mainly radial rising distributions for the heated disks with radial rising temperature *** the present work,at the Reynolds number of 20 000,the disk local Nusselt numbers are the correlations of the local Grashof number to the power of 1.89-2.6,and the value of the power is increased as the rotational Reynolds number goes *** the rotational Reynolds number of 800 000,the local Nusselt numbers are the correlations of the local Grashof number to the power of 0.68-2.6,and the value of the power is decreased as Reynolds number goes *** area-averaged disk Nusselt number is the correlation of the Reynolds number to the power of 0.479 and the rotational Grashof number to the power of 0.12.

关键词： buoyancy force Coriolis force rotating cavity heat transfer turbine

Effect of Tempering Temperature on Microstructure and Mechanical Properties of Steel Containing Ni of 9%

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Journal of Iron and Steel Research International 2011年第9期18卷 47-51,58页

作者： ZHAO Xi-qing PAN Tao WANG qing-feng SU hang YANG Cai-fu YANG qing-xiang State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Division of Structural Material Research Central Iron and Steel Research InstituteBeijing 100081China

Mechanical properties of quenching,intercritical quenching and tempering （QLT） treated steel containing Ni of 9% were evaluated from specimens subject to various tempering temperatures. The detailed microstructures of steel containing Ni of 9% at different tempering temperatures were observed by optical microscope （OM） and transmission electron microscope （TEM）. The volume fraction of austenite was estimated by XRD. The results show that high strength and cryogenic toughness of steel containing Ni of 9% are obtained when the tempering temperature are between 540 and 580 ℃. The microstructure keeps the dual phase lamellar structure after the intercritical quenching and there is cementite created in the Ni-rich constituents when tempering temperature is 540 ℃. When tempering temperatures are between 560 and 580 ℃,the reversed austenites （γ′） grow up and the dual phase lamellar structure is not clear. The γ′ becomes instable at 600 ℃. When tempered at temperature ranging from 500 to 520 ℃,the increase of dislocation density in the lamellar matrix makes both tensile strength and yield strength decrease. When tempered at 540 ℃ and higher temperature,the yield strength decreases continuously because the C and alloying elements in the matrix are absorbed by the cementite and the γ′,so the yield ratio is decreased by the γ′. There are two toughness mechanisms at different tempering temperatures. One is that the precipitation of cementite absorbs the carbon in the steel which plays a major role in improving cryogenic toughness at lower temperature. Another is that the γ′ and the purified matrix become major role at higher tempering temperature. When the tempering temperature is 600 ℃,the stability of γ′ is decreased quickly,even the transformation takes place at room temperature,which results in a sharp decrease of Charpy-V impact energy at 77 K. The tempering temperature range is enlarged by the special distribution of cementite and the lamellar structure.

关键词： steel containing Ni of 9% tempering temperature cementite reversed austenite cryogenic toughness

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Error modeling and compensating of a novel 6-DOF aeroengine rotor docking equipment

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Chinese Journal of Aeronautics 2022年第6期35卷 312-324页

作者： Tianyi ZHOU hang GAO Xuanping WANG Lun LI qing LIU Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China AECC Shenyang Liming Aero-engine Co. LtdChina

In the docking process of aeroengine rotor parts,docking accuracy that indicates the gaps between the end faces is strictly required.A key issue is improving docking accuracy using automated docking *** this paper,a systematic study is carried out on the error modeling and compensation of a novel six-degrees-of-freedom(6-DOF)docking equipment for aeroengine ***,a new model for indicating the main indexes of docking accuracy is ***,the error model of a specially designed 6-DOF docking equipment is established based on a modified Denavit Hartenberg method with five ***,two error compensation methods are *** on the above models,a docking accuracy simulation algorithm is proposed using the Monte Carlo ***,verification experiments are *** results show that,for the maximum values and standard deviations of the gaps between the rotor end-faces in the actual and target positions and attitudes,i.e.,main indexes that represent docking accuracy,the deviation rates between the simulation and experimental results are less than20%.The modeling methods have referential *** decline rates of these values are 50–65%when using the two proposed compensation *** compensation methods significantly improve the docking accuracy.

关键词： Accuracy analysis Aeroengine rotor Docking Error compensation Error models Multi-degree-of-freedom structures