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Cobalt-Catalyzed C-H Allylation of Arenes with Allylic Amines

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Chinese Journal of Chemistry 2021年第5期39卷 1205-1210页

作者： Rui Yan hang yu Zhong-Xia Wang CAS Key Laboratory of Soft Matter Chemistry and Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China Colloborotive Innovation Center of Chemical Science and Engineering Tianjin 300072China

[Cp^(*)Co(CO)l_(2)]effectively catalyzes pyridyl-directed C-H allylation of arenes with allylic amines in the presence of AgOAc and CF_(3)*** reaction features ortho-position monoallylation of 2-pyridylarenes,giving the allylated arenes in moderate to high yields.A range of functional groups including OMe,Me,Ph,F,Cl,Br,CF_(3),C(0)Me,COOEt,and COOH groups are ***-idyl-directed C-H allylation of arenes were also performed under the same *** of 2-phenylpyrimidine,2-(4-methoxyphenyl)pyrimidine/and 2-(3-fluorophenyl)pyrimidine leads to a mixture of ortho-position mono-and bisallylation *** of other 2-(substituted aryl)pyrimidines resulted in ortho-position monoallylation products.

关键词： C-H activation C-N activation Homogeneous catalysis Cobalt catalysis Allylation

Classical Theory of Hot-Electron Transport in Electric and Magnetic Fields

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Communications in Theoretical Physics 2002年第3期38卷 370-374页

作者： WENG Ming-Qi wu hang-Sheng Department of Physics University of Science and Technology of China Hefei 230026 China Department of Physics University of Science and Technology of China Hefei 230026 China

Balance equation approach to the hot-electron transport in electric and magnetic fields is *** balance equations are re-derived from the Boltzmann equation. A new expression for the distribution function isreported in the present paper. It is homogeneous steady solution of the Boltzmann equation in constant relaxation timeapproximation. It holds when ωocτ < i or ωc < Te. As an example, the mobility of 2D electron gas in the GaAs-AlGaAsheterojunction is computed as a function of electric field and magnetic field.

关键词： hot-electron transport, balance equation, Boltzmann equation, mobility

Theoretical research into low-voltage Na_(2)TiSiO_(5)anode for lithium-ion battery

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Rare Metals 2022年第10期41卷 3412-3420页

作者： Shu Zhao Tian-Hao wu Di He Zi-He Zhang Bo-Ya Wang Li-hang Wang Hai-Jun yu Institute of Advanced Battery Materials and Devices Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing100124China Key Laboratory of Advanced Functional Materials Beijing University of TechnologyMinistry of EducationBeijing100124China

Na_(2)TiSiO_(5)(NTSO)is a low-cost Li-ion battery anode with great application potential,such as the tetragonal NTSO(T-NTSO)with a high capacity and a low *** addition to the tetragonal structure,NTSO has two other ***,the basic understanding of the structure,ion insertion and transport mechanisms of these new materials is still ***,we present a combined experimental and computational investigation of the tetragonal and orthorhombic NTSO to reveal the intrinsic mechanism leading to the superior electrochemical performance of *** determined that the insertion site with a flexible Ti^(4+)/Ti^(3+)redox pair is critical for Li+insertion *** large number of such flexible sites in the T-NTSO results in a higher capacity and higher ionic conductivity than those of orthorhombic *** understanding of intrinsic properties will accelerate the development and utilization of titanosilicates as the next generation low-voltage anode of Li-ion battery.

关键词： Lithium-ion batteries Anode materials Titanosilicates First-principles calculations Flexible redox pair

On parametric approach of aerial robots' visual navigation

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Journal of Systems Engineering and Electronics 2008年第5期19卷 1010-1016页

作者： Zhou yu Huang Xianlin Jie Ming Yin hang Harbin Inst. of Technology Harbin 150001 P. R. China

In aerial robots＇ visual navigation, it is essential yet very difficult to detect the attitude and position of the robots operated in real time. By introducing a new parametric model, the problem can be reduced from almost unmanageable to be partly solved, though not fully, as per the requirement. In this parametric approach, a multi-scale least square method is formulated first. By propagating as well as improving the parameters down from layer to layer of the image pyramid, a new global feature line can then be detected to parameterize the attitude of the robots. Furthermore, this approach paves the way for segmenting the image into distinct parts, which can be realized by deploying a Bayesian classifier on the picture cell level. Comparison with the Hough transform based method in terms of robustness and precision shows that this multi-scale least square algorithm is considerably more robust to noises. Some discussions are also given.

关键词： parametric model aerial robots visual navigation multi-scale least square.

Floor positioning method indoors with smartphone’s barometer

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Geo-Spatial Information Science 2019年第2期22卷 138-148,I0006页

作者： Min yu Feng Xue Chao Ruan hang Guo College of Computer Information and Engineering Jiangxi Normal UniversityNanchangChina Institute of Space Science and Technology Nanchang UniversityNanchangChina

This paper presents an indoor floor positioning method with the smartphone’s barometer for the purpose of solving the problem of low availability and high environmental dependence of the traditional floor positioning ***,an initial floor position algorithm with the“entering”detection algorithm has been ***,the user’s going upstairs or downstairs activities are identified by the characteristics of the air pressure ***,the moving distance in the vertical direction and the floor change during going upstairs or downstairs are estimated to obtain the accurate floor *** order to solve the problem of the floor misjudgment from different mobile phone’s barometers,this paper calculates the pressure data from the different cell phones,and effectively reduce the errors of the air pressure estimating the elevation which is caused by the heterogeneity of the mobile *** experiment results show that the average correct rate of the floor identification is more than 85%for three types of the cell phones while reducing environmental dependence and improving ***,this paper compares and analyzes the three common floor location methods–the WLAN Floor Location(WFL)method based on the fingerprint,the Neural Network Floor Location(NFL)methods,and the Magnetic Floor Location(MFL)method with our *** experiment results achieve 94.2%correct rate of the floor identification with Huawei mate10 Pro mobile phone.

关键词： Floor positioning smartphone’s barometer sensor calibration indoor location service

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

Ag-modified hydrogen titanate nanowire arrays for stable lithium metal anode in a carbonate-based electrolyte

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Journal of Energy Chemistry 2021年第3期30卷 282-290页

作者： Zhipeng Wen Dongzheng wu hang Li Yingxin Lin hang Li Yang Yang Jinbao Zhao State Key Lab of Physical Chemistry of Solid Surfaces Collaborative fnnovation Centre of Chemistry for Energy MaterialsState-Province JointEngineering Laboratory of Power Source Technology for New Energy VehicleEngineering Research Center of Electrochemical TechnologyMinistiy of EducationCollege of Chemistiy and Chemical EnginesringXiamen UniversityXiamen 361005FujianChina College of Energy&School of Energy Research Xiamen University Xiamen 361102FujianChina School of Chemical Engineering cmd Light Industry Guangdong University of TechnologyGuangzhou 510006CuangdongChina

In the investigation of the next-generation battery anode,Li metal has attracted increasing attention owing to its ultrahigh specific capacity and low reduction ***,its low columbic efficiency,limited cycling life,and serious safety hazards have hindered the practical application of rechargeable Li metal *** several strategies have been proposed to enhance the electrochemical performance of Li metal anodes,most are centered around ether-based electrolytes,which are volatile and do not provide a sufficiently large voltage ***,we aimed to attain stable Li deposition/stripping in a commercial carbonate-based ***,we have successfully synthesized hydrogen titanate(HTO)nanowire arrays decorated with homogenous Ag nanoparticles(NPs)(Ag@HTO)via simple hydrothermal and silver mirror *** 3 D cross-linked array structure with Ag NPs provides preferable nucleation sites for uniform Li deposition,and most importantly,when assembled with the commercial LiNi_(0.5)Co0.2Mn_(0.3)O_(2) cathode material,the Ag@HTO could maintain a capacity retention ratio of 81.2% at 1 C after 200 cycles,however the pristine Ti foil failed to do so after only 60 *** research therefore reveals a new way of designing current collectors paired with commercial high voltage cathodes that can create high energy density Li metal batteries.

关键词： Hydrogen titanate nanowire arrays Ag nanoparticles Li metal anode Carbonate-based electrolyte

Experimental observations on the nonproportional multiaxial ratchetting of cast AZ91 magnesium alloy at room temperature

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1115-1125页

作者： Binghui Hu yu Lei hang Li Ziyi Wang Chao yu Guozheng Kang Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The nonproportional multiaxial ratchetting of cast AZ91 magnesium (Mg) alloy was examined by performing a sequence of axial-torsional cyclic tests controlled by stress with various loading paths at room temperature (RT).The evolutionary characteristics and path dependence of multiaxial ratchetting were *** illustrate that the cast AZ91 Mg alloy exhibits considerable nonproportional additional softening during cyclic loading with multiple nonproportional multiaxial loading paths;multiaxial ratchetting presents strong path dependence,and axial ratchetting strains are larger under nonproportional loading paths than under uniaxial and proportional45°linear loading paths;multiaxial ratchetting becomes increasingly pronounced as the applied stress amplitude and axial mean stress ***,stress-strain curves show a convex and symmetrical shape in axial/torsional *** ratchetting exhibits quasi-shakedown after certain loading *** abundant experimental data obtained in this work can be used to develop a cyclic plasticity model of cast Mg alloys.

关键词： cast magnesium alloy ratchetting multiaxial loading loading path stress level

The mechanical and water absorption properties of carbon fiber buoyancy materials under hydrostatic pressure

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Science China Technological Sciences 2025年第1期 251-265页

作者： Fanglin CONG Zihan LI Guocai yu Yang JIN Zixu ZHU Linzhi wu College of Aerospace and Civil Engineering Harbin Engineering University Key Laboratory of Advanced Ship Materials and Mechanics Harbin Engineering University Department of Basic Courses Naval University of Engineering

Buoyancy material technology is of paramount importance for the development of marine engineering. In this study,a novel carbon fiber buoyancy material(CFBM) is designed and prepared by utilizing composite circular tubes with light weight and high strength. To reveal the failure mechanism under hydrostatic pressure, a finite element model(FEM) based on the three-dimensional Hashin and Yeh failure criterion is developed and validated experimentally. Both the simulated and experimental results indicate that the hydrostatic strength of the CFBM is mainly determined by the buckling of carbon fiber tubes located at the edges of the CFBM. Parametric analysis is conducted to investigate the effect of the number of unit-cells,length, and wall thickness of carbon fiber tubes on the mechanical properties of the CFBM. In addition, a 60-day water absorption test of the CFBM at 12.5 MPa is conducted to characterize its durability. Experimental results indicate that the maximum water absorption rate of the CFBM is 0.59% and the hydrostatic strength is reduced by only 7.97% during the 60-day test period. Finally, the designed CFBM is used at the water depth of 1000 m as buoyancy material. Compared with traditional buoyancy materials, the proposed CFBM has significant advantages in both hydrostatic strength and density. This work has broad engineering application prospects and is of high significance for promoting the implementation of carbon fiber composites in the ocean engineering field.

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