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Rh single atom catalyst for direct conversion of methane to oxygenates

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Science China Materials 2018年第5期61卷 758-760页

作者： jian lin Xiaodong Wang State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Along with the fast development of economy and growthof world＇s population, the demand for energy is sig-nificantly enhanced. The conventional petroleum andcoal resources are unrenewable and bring about severepollution to the environment. In the past decade, thetechnological advances in drilling and exploitation lead toa significant increase in the production capacity of shalegas worldwide.

关键词：中国科学材料科学

Support vector classification algorithm based on variable parameter linear programming

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Journal of Systems Engineering and Electronics 2007年第2期18卷 355-359页

作者： Xiao jianhua lin jian Systems Science and Technology Inst. Wuyi Univ. Jiangmen 529020 P. R. China School of Economy and Management Beijing Univ. of Aeronautics and Astronautics Beijing 100083 P. R. China

To solve the problems of SVM in dealing with large sample size and asymmetric distributed samples, a support vector classification algorithm based on variable parameter linear programming is proposed. In the proposed algorithm, linear programming is employed to solve the optimization problem of classification to decrease the computation time and to reduce its complexity when compared with the original model. The adjusted punishment parameter greatly reduced the classification error resulting from asymmetric distributed samples and the detailed procedure of the proposed algorithm is given. An experiment is conducted to verify whether the proposed algorithm is suitable for asymmetric distributed samples.

关键词： Support vector machine linear programming Classification Variable parameter.

Repeater-Assisted Zeno Effect in Classical Stochastic Processes

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Chinese Physics Letters 2012年第1期29卷 17-19页

作者： gu Shi-jian WANG Li-Gang WANG Zhi-guo lin Hai-Qing Department of Physics and ITP The Chinese University of Hong KongHong Kong Department of Physics Zhejiang UniversityHangzhou 310027 Department of Physics Tongji UniversityShanghai 200092

We address the possibility of the classical Zeno effect in classical stochastic processes as sampled by transferring a digitized image through a classical channel with surrounding *** is shown that the the classical state of the image decays inevitably with the distance of the channel due to the interference of the ***,if there are enough repeaters,which can both check and recover the state’s information,the classical state’s decay rate will be significantly suppressed,then a classical Zeno effect might occur.

关键词： decay stochastic digit

Electrical arc contour cutting based on a compound arc breaking mechanism

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Advances in Manufacturing 2022年第4期10卷 583-595页

作者： guo-jian He lin gu Ying-Mou Zhu Ji-Peng Chen Wan-Sheng Zhao K.P.Rajurkar State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240People’s Republic of China School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Center for Nontraditional Manufacturing Research University of Nebraska-LincolnLincolnNEUSA

Electrical arc contour cutting(EACC)is a novel high-efficiency material cutting process that applies arc plasma to perform efficient and economical contour cutting of difficult-to-cut *** to conventional electrical arc machining(EAM),this process can remove the allowance of open structures and plates in bulk mode,rather than entirely in the form of *** with existing contour cutting methods,EACC possesses the advantages of high cutting efficiency and a deep cutting ***,a compound arc breaking mechanism(CABM),which integrates hydrodynamic force and mechanical motion,has been applied to control the discharge arc column in EACC,while also strengthening the debris expelling effect in the narrow discharge *** CABM implementation conditions were studied,based on arc column distortion images captured by a high-speed camera and simulation results of the flow field and debris distribution.A set of machining experiments was designed and conducted to optimize the performance of the proposed ***,a SiC_(p)/Al metal matrix composite(MMC)space station workpiece was machined to verify the feasibility and efficiency of this process.

关键词： Electrical arc contour cutting(EACC) Electrical arc machining(EAM) Compound arc breaking mechanism(CABM) SiC_(p)/Al metal matrix composite(MMC) High efficiency

Scaling of the Leading Response in linear Quench Dynamics in the Quantum Ising Model

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Chinese Physics Letters 2012年第8期29卷 194-197页

作者： YU Wing-Chi WANG Li-Gang gu Shi-jian lin Hai-Qing Department of Physics and ITP The Chinese University of Hong KongHong Kong

We study the scaling behavior of the linear response in the quench dynamics in the one-dimensional transverse-field Ising *** is found that the leading response of the system scales linearly with the system *** considering the second derivative of the leading term of the response,we also found that it exhibits a non-trivial scaling behavior at the quantum critical point of the model.

关键词： model scaling Ising

Practical Timing Synchronization for Network Dynamics in Large Machine-to-Machine Networks

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China Communications 2016年第10期13卷 160-168页

作者： Lei gu Shih-Chun lin Fudan University and China Telecom Research Center Bank of Communication Ltd. the School of Electrical and Computer Engineering Georgia Institute of Technology

Efficient multi-machine cooperation and network dynamics still remain open that jeopardize great applications in largescale machine-to-machine(M2M) networks. Among all possible machine cooperation controls, to synchronize tremendous machines in a timing-efficient brings one of the greatest challenge and serves as the foundation for any other network control policies. In this paper, we propose a linear-time synchronization protocol in large M2M networks. Specifically, a closed-form of synchronization rate is provided by developing the statistical bounds of the second smallest eigenvalue of the graph Laplacian matrix. These bounds enable the efficient control of network dynamics, facilitating the timing synchronization in networks. Through a practical study in Metropolis, simulation results confirm our theoretical analysis and provide effective selection of wireless technologies, including Zigbee, Wi-Fi, and cellular systems, with respect to the deployed density of machines. Therefore, this paper successfully demonstrates a practical timing synchronization, to make a breakthrough of network dynamic control in real-world machine systems, such as Internet of Things.

关键词： timing synchronization network dynamics graph Laplacian matrix distributed protocol internet of things(IoTs) machine-to-machine(M2M) communications

Seismic performance evaluation of steel frame-steel plate shear walls system based on the capacity spectrum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 322-329页

作者： jian-hua SHAO Qiang gu Yong-kang SHEN College of Civil Engineering Hohai University Nanjing 210098 China Department of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China

This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom （SDOF） system. The capacity spectrum method （CSM） is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls （SPSW） is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.

关键词： Steel frame-steel plate shear walls (SPSW) system Capacity spectrum method (CSM) Seismic demand spectrum Base shear force-roof displacement Seismic performance evaluation

Superconducting Single-Layer T-Graphene and Novel Synthesis Routes

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Chinese Physics Letters 2019年第9期36卷 46-63页

作者： Qinyan gu Dingyu Xing jian Sun National Laboratory of Solid State Microstructures School of Physics and Collaborative Innovation Center of Ad vanced MicrostructuresNanjing UniversityNanjing 210093

Single-layer superconductors are ideal materials for fabricating superconducting nano ***,up to date,very few single-layer elemental superconductors have been predicted and especially no one has been successfully synthesized ***,using crystal structure search techniques and ab initio calculations,we predict that a single-layer planar carbon sheet with 4-and 8-membered rings called T-graphene is a new intrinsic elemental superconductor with superconducting critical temperature(Tc)up to around 20.8 *** importantly,we propose a synthesis route to obtain such a single-layer T-graphene,that is,a T-graphene potassium intercalation compound(C4 K with P4/mmm symmetry)is firstly synthesized at high pressure(>11.5 GPa)and then quenched to ambient condition;and finally,the single-layer T-graphene can be either exfoliated using the electrochemical method from the bulk C4 K,or peeled off from bulk T-graphite C4,where C4 can be obtained from C4 K by evaporating the K ***,we find that the calculated Tc of C4 K is about 30.4 K at 0 GPa,which sets a new record for layered carbon-based *** present findings add a new class of carbon-based *** particular,once the single-layer T-graphene is synthesized,it can pave the way for fabricating superconducting devices together with other 2 D materials using the layer-by-layer growth techniques.

关键词： red Superconducting Single-Layer T-Graphene and Novel Synthesis Routes Graphene

PREDICTION OF VORTEX-INDUCED VIBRATION OF LONG FLEXIBLE CYlinDERS MODELED BY A COUPLED NONlinEAR OSCILLATOR:INTEGRAL TRANSFORM SOLUTION

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Journal of Hydrodynamics 2012年第6期24卷 888-898页

作者： gu Ji-jun AN Chen LEVI Carlos SU jian Ocean Engineering Program COPPEUniversidade Federal do Rio de Janeiro Nuclear Engineering Program COPPEUniversidade Federal do Rio de Janeiro

The Generalized Integral Transform Technique （GITT） was applied to predict dynamic response of Vortex-Induced Vibration （VIV） of a long flexible cylinder. A nonlinear wake oscillator model was used to represent the cross-flow force acting on the cylinder, leading to a coupled system of second-order Partial Differential Equations （PDEs） in temporal variable. The GITT approach was used to transform the system of PDEs to a system of Ordinary Differential Equations （ODEs）, which was numerically solved by using the Adams-Moulton and Gear method （DIVPAG） developed by the International Mathematics and Statistics Library （IMSL）. Numerical results were presented for comparison to those given by the finite difference method and experimental results, allowing a critical evaluation of the technique performance. The influence of variation of mean axial tension induced by elongation of flexible cylinder was evaluated, which was shown to be not negligible in numerical simulation of VIV of a long flexible cylinder.

关键词： Vortex-Induced Vibration (VIV) nonlinear wake oscillator flexible cylinder integral transform