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Carbon Energy 2024年第3期6卷 204-214页

作者： bin liu Jie liu Cheng Zhong Wenbin Hu Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) School of Materials Science and EngineeringTianjin UniversityTianjinChina Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjinChina Joint School of National University of Singapore and Tianjin University TianjinChina International Campus of Tianjin University Binhai New CityFuzhouChina

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first *** this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing *** show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the *** obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg *** the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).

关键词： initial Coulombic efficiency lithium-ion batteries magnesium doping prelithiation silicon suboxide

EXISTENCE AND UNIQUENESS AND STABILITY OF SOLUTIONS FOR STOCHASTIC IMPULSIVE SYSTEMS

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Journal of Systems Science & Complexity 2007年第1期20卷 149-158页

作者： bin liu Xinzhi liu Xiaoxin LIAO Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 Department of Information and Computation Science Zhuzhou Institute of Technology Zhuzhou 412008 China Department of Applied Mathematics University of Waterloo Waterloo Ontario N2L 3G1 Canada. Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

This paper studies the existence, uniqueness, and stability of solutions for stochastic impulsive systems. By employing Lyapunov-like functions, some sufficient conditions of the global existence, uniqueness, and stability of solutions for stochastic impulsive systems are established. Furthermore, the results are specialized to the case of linear stochastic impulsive systems. Finally, some examples are given to illustrate the applications of our theory.

关键词： Ito's formula Lyapunov-like function stability stochastic impulsive system.

A visible-light-assisted Pd/TiO_(2)gas sensor with carbon nanotubes electrodes for trace formaldehyde detection

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Rare Metals 2024年第1期43卷 257-266页

作者： Can liu Qiao-Qiao Zou bin liu Yong Zhang School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Owing to the ppb-level detection standard toward the toxic and harmful gas,the detection of trace gases has become an important subject in the field of indoor environment ***,the traditional resistive gas sensors hardly meet the requirement due to the weak signal generated by trace gas molecules that are difficult to ***,a visible-light-assisted Pd/TiO_(2)gas sensor is proposed to endow the effective detection of trace formaldehyde(HCHO)gas without heating *** from the enhanced photocatalytic properties of TiO_(2)by Pd decoration,the visible-light-assisted Pd/TiO_(2)gas sensor can detect the HCHO gas as low as80×10^(–9)at room *** successful preparation of nanoscale TiO_(2)sensing layer is facilitated by the ultrathin carbon nanotube interdigital electrode in the gas sensor,which avoids the discontinuity of the sensing layer caused by the excessive thickness of the traditional metal *** addition,the whole preparation process of the Pd/TiO_(2)gas sensor with carbon nanotube electrodes is compatible with mainstream CMOS fabrication technology,which is expected to realize the batch fabrication and micro-integrated application of gas *** is expected that our work can provide a new strategy for the batch preparation of high-performance trace HCHO gas sensors and their future applications in portable electronic devices such as smartphones.

关键词： Visible-light-assisted gas sensor Pd/TiO_(2) Trace HCHO detection Carbon nanotubes electrodes

Determination of atmospheric hydroxyl radical by HPLC coupled with electrochemical detection

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Journal of Environmental Sciences 2008年第1期20卷 28-32页

作者： liu bin WANG Hui-xiang College of Environmental Sciences Peking University Beijing 100871 China

The hydroxyl radical （·OH） plays a central role in the oxidation and removal of many atmospheric compounds. Measurement of atmospheric ·OH is very difficult because of its high reactivity and low atmospheric abundance. In this article, a simple and highly sensitive method, high performance liquid chromatography coupled with coulometric detection （HPLC-CD）, was developed to determine ·OH indirectly by determining its reaction products with salicylic acid （SAL）, 2,3-dihydroxybenzoic acid （2,3-DHBA）, and 2,5-dihydroxybenzoic acid （2,5-DHBA）. Under the optimum conditions for its determination, 2,3-DHBA and 2,5-DHBA could be well separated and the detection limits for 2,3-DHBA were 3 ×10^-10 mol/L and for 2,5-DHBA were 1.5 ×10^-10 mol/L, which were lower than most previous reports. This method was also applied to measure atmospheric hydroxyl radical levels and demonstrated the feasibility in clean and polluted air.

关键词： electrochemical detection HPLC hydroxyl radical troposphere

Weakening internal diffusion effect in selective hydrodesulfurization of FCC gasoline by novel designed eggshell CoMoS/Al_2O_3 catalysts

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Journal of Natural Gas Chemistry 2012年第2期21卷 194-199页

作者： bin liu Yongming Chai Yajing Wang Yunqi liu Chenguang liu State Key Laboratory of Heavy Oil Processing Key Laboratory of CatalysisChina National Petroleum Corp.(CNPC)China University of Petroleum(East China)Qingdao 266555ShandongChina

A simple method for preparation of presulfided eggshell CoMoS/γ-Al2O3 catalysts with sharp boundary is developed, through which the eggshell thicknesses of Co and Mo could be easily regulated by controlling the impregnation time. According to the results characterized by EDS, XRD, HRTEM and FT-IR of adsorbed CO, the active component structures, the nature and/or the amount of active sites on the eggshell catalyst are similar to these on the uniform catalyst. The evaluation results of the catalytic performance in selective hydrodesulfurization （HDS） of FCC gasoline show the presence of significant internal diffusion inhibition effect on HDS of S-compounds especially in the uniform catalyst. Compared with uniform catalyst, the eggshell catalyst could remarkably reduce such an internal diffusion inhibition effect due to a shortened diffusion path of the reactants, thus showing higher HDS activity and selectivity.

关键词： CoMoS/γ-Al2O3 eggshell catalyst uniform catalyst internal diffusion hydrodesulfurization

A Modeling Language Based on UML for Modeling Simulation Testing System of Avionic Software

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Chinese Journal of Aeronautics 2011年第2期24卷 181-194页

作者： WANG Lize liu bin LU Minyan Department of Project Systems Engineering Beihang University Beij ing 100191 China

With direct expression of individual application domain patterns and ideas,domain-specific modeling language（DSML） is more and more frequently used to build models instead of using a combination of one or more general *** on the profile mechanism of unified modeling language（UML） 2.2,a kind of DSML is presented to model simulation testing systems of avionic software（STSAS）.To define the syntax,semantics and notions of the DSML,the domain model of the STSAS from which we generalize the domain concepts and relationships among these concepts is given,and then,the domain model is mapped into a UML meta-model,named UML-STSAS *** a flight control system（FCS） as system under test（SUT）,we design the relevant *** results indicate that extending UML to the simulation testing domain can effectively and precisely model STSAS.

关键词： avionics hardware-in-the-loop test facilities meta-model UML profile domain-specific modeling language abstract state machine

Semantic segmentation of high-resolution images

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Science China(Information Sciences) 2017年第12期60卷 256-261页

作者： Juhong WANG bin liu Kun XU Department of Computer Science and Technology Tsinghua University

Image semantic segmentation is a research topic that has emerged recently. Although existing approaches have achieved satisfactory accuracy, they are limited to handling low-resolution images owing to their large memory consumption. In this paper, we present a semantic segmentation method for high-resolution images. First, we downsample the input image to a lower resolution and then obtain a low-resolution semantic segmentation image using state-of-the-art methods. Next, we use joint bilateral upsampling to upsample the low-resolution solution and obtain a high-resolution semantic segmentation image. To modify joint bilateral upsampling to handle discrete semantic segmentation data, we propose using voting instead of interpolation in filtering computation. Compared to state-of-the-art methods, our method significantly reduces memory cost without reducing result quality.

关键词： image semantic segmentation high-resolution images joint bilateral upsampling

Global Dynamic Characteristic of Nonlinear Torsional Vibration System under Harmonically Excitation

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 132-139页

作者： SHI Peiming liu bin HOU Dongxiao Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 China

Torsional vibration generally causes serious instability and damage problems in many rotating machinery parts. The global dynamic characteristic of nonlinear torsional vibration system with nonlinear rigidity and nonlinear friction force is investigated. On the basis of the generalized dissipation Lagrange＇s equation, the dynamics equation of nonlinear torsional vibration system is deduced. The bifurcation and chaotic motion in the system subjected to an external harmonic excitation is studied by theoretical analysis and numerical simulation. The stability of unperturbed system is analyzed by using the stability theory of equilibrium positions of Hamiltonian systems. The criterion of existence of chaos phenomena under a periodic perturbation is given by means of Melnikov＇s method. It is shown that the existence of homoclinic and heteroclinic orbits in the unperturbed system implies chaos arising from breaking of homoclinic or heteroclinic orbits under perturbation. The validity of the result is checked numerically. Periodic doubling bifurcation route to chaos, quasi-periodic route to chaos, intermittency route to chaos are found to occur due to the amplitude varying in some range. The evolution of system dynamic responses is demonstrated in detail by Poincare maps and bifurcation diagrams when the system undergoes a sequence of periodic doubling or quasi-periodic bifurcations to chaos. The conclusion can provide reference for deeply researching the dynamic behavior of mechanical drive systems.

关键词： nonlinear torsional vibration dynamics behavior bifurcation chaos Melnikov's method

Quantum position verification in bounded-attack-frequencymodel

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Science China(Physics,Mechanics & Astronomy) 2016年第11期59卷 17-27页

作者： Fei Gao bin liu QiaoYan Wen State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications College of Computer Science Chongqing University

In 2011, Buhrman et al. proved that it is impossible to design an unconditionally secure quantum position verification(QPV)protocol if the adversaries are allowed to previously share unlimited entanglements. Afterwards, people started to design secure QPV protocols in practical settings, e.g. the bounded-storage model, where the adversaries' pre-shared entangled resources are supposed to be limited. Here we focus on another practical factor that it is very difficult for the adversaries to perform attack operations with unlimitedly high frequency. Concretely, we present a new kind of QPV protocols, called non-simultaneous *** we prove the security of a specific non-simultaneous QPV protocol with the assumption that the frequency of the adversaries' attack operations is bounded, but no assumptions on their pre-shared entanglements or quantum storage. Actually, in our nonsimultaneous protocol, the information whether there comes a signal at present time is also a piece of command. It renders the adversaries "blind", that is, they have to execute attack operations with unlimitedly high frequency no matter whether a signal arrives, which implies the non-simultaneous QPV is also secure in the bounded-storage model.

关键词： quantum cryptography position-based cryptography quantum position verification

Influence of cross correlation step length on the surface stress of thin laser cladding Fe314 alloy coatings

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 549-554页

作者： bin liu Shi-yun Dong bin-shi Xu Peng He State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Harbin 150001 China National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China

To measure the surface stress of thin laser cladding coatings with Rayleigh waves based on the cross correlation function, this pa- per introduced the influence of cross correlation step length on the stress measurement. Flat-shaped specimens made of laser cladding Fe314 alloy coatings were performed by static tensile tests, and Rayleigh wave signals were collected during the test process with an ultrasonic pulser and receiver instrument combined with two Rayleigh wave transducers. The difference in time of flight between two signals was de- termined based on the cross correlation function. The microstructure was observed by scanning electronic microscopy. The influence of the stress on the propagation velocity of Rayleigh waves and the relationship between the difference in time of flight and tensile stress under dif- ferent cross correlation step lengths were analyzed. The inhomogeneous deformation of the coatings affects the relationship between the dif- ference in time of flight and tensile stress; the stress measurement of the coatings is nearly constant with the increase of cross correlation step length when it attains one cycle.

关键词： iron alloys metal cladding laser cladding surface stress Rayleigh waves