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Chemical Research in Chinese Universities 2010年第2期26卷 331-334页

作者： WU Xiang-mei WANG Yan guo sheng-rong College of Chemistry and Life Science Lishui University Lishui 323000 P. R. China

1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymmetrical biaryls from arylboronic acids and aryl halides in a single step. However, the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand, which sometimes creates practical problems because organophosphines tend to be expensive, poisonous, and air sensitive. Recently, phos-phine-free ligands,

关键词： Suzuki reaction Phosphine-free ligand Palladium 4-Amino-1,2,4-triazole resin

Low-temperature Growth of Single-crystal SrCO_3 Nanoneedles

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Chinese Chemical Letters 2005年第8期16卷 1101-1104页

作者： Guang sheng guo Fu Bo GU Zhi Hua WANG Hong You guo Key Lab. for Science and Technology of Controllable Chemical Reactions Education Ministry Beijing University of Chemical Technology Beijing 100029

Single-crystal SrCO3 nanoneedles were synthesized in reverse micelles at low temperature. The products were characterized by X-ray diffraction, X-ray energy dispersive spectrometer, transmission electron microscopy and selected area electronic diffraction. The influences of experimental conditions on the morphologies of the products were discussed. The growth mechanism of SrCO3 nanoneedles in reverse micelles were proposed.

关键词： Nanoneedles,SrCO3 reverse micelle.

Routh table test for stability of commensurate fractional degree polynomials and their commensurate fractional order systems

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Control Theory and Technology 2019年第3期17卷 297-306页

作者： sheng-guo WANG Shu LIANG Liang MA Kaixiang PENG College of Engineering and College of Computing and Informatics University of North Carolina at Charlotte NC 28223-0001 U.S.A. School of Automation and Electrical Engineering University of Science and Technology Beijing Beijing 100083 China

A Routh table test for stability of commensurate fractional degree polynomials and their commensurate fractional order systems is presented via an auxiliary integer degree polynomial. The presented Routh test is a classical Routh table test on the auxiliary integer degree polynomial derived from and for the commensurate fractional degree polynomial. The theoretical proof of this proposed approach is provided by utilizing Argument principle and Cauchy index. Illustrative examples show efficiency of the presented approach for stability test of commensurate fractional degree polynomials and commensurate fractional order systems. So far, only one Routh-type test approach [1] is available for the commensurate fractional degree polynomials in the literature. Thus, this classical Routh-type test approach and the one in [1] both can be applied to stability analysis and design for the fractional order systems, while the one presented in this paper is easy for peoples, who are familiar with the classical Routh table test, to use.

关键词： Fractional order systems stability commensurate fractional degree polynomials Routh table test

Numerical stress analysis for the multi-casing structure inside a wellbore in the formation using the boundary element method

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Petroleum Science 2017年第1期14卷 126-137页

作者： Wan Cheng Yan Jin Mian Chen guo-sheng Jiang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Faculty of Engineering China University of Geosciences

A multi-casing structure in drilling engineering can be considered as an inhomogeneous body consisting of many different materials. The mechanical behavior of the inhomogeneous body in an infinite domain is very com- plicated. In this paper, a detailed expression about the fictitious stress method of the boundary element method （BEM） is demonstrated for the inhomogeneous body. Then the fictitious stress method is deployed to investigate the stresses for the multi-casing structure under non-uniform loading conditions and an irregular wellbore. Three examples of the multi-casing structure in the borehole imply the high effectiveness of BEM for complex geometries related to the borehole in an infinite formation. The effects of casing eccentricity and the interfacial gap on the stress field are discussed. The eccentric casing takes the potential yield when the eccentric orientation is along the direction of Sh. Under different eccentric orientations, the yon Mises stress in the casing increases with increasing degree of eccentricity. The radial stress in the multi-casing structure is always continuous along the radius, but the circumferential stress is discontinuous at the interface. The radial stress decreases and the circumferential stress increases with the increasing of the interfacial gap between the adjacent materials.

关键词： Displacement discontinuity method Fictitiousstress method Drilling mechanics Wellbore stressconcentration Inhomogeneous body

Analysis of delamination in thin film electrodes under galvanostatic and potentiostatic operations with Li-ion diffusion from edge

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Acta Mechanica Sinica 2013年第3期29卷 348-356页

作者： Bo Lu Yi-Cheng Song Zhan-sheng guo Jun-Qian Zhang Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Department of Mechanics Shanghai University Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University

Progressive delamination driven by Li-ion diffusion in elastic disk-like thin film electrodes of Li-ion batteries is modeled based on the cohesive model. Axisymmetric diffusion model is considered under both galvanostatic and potentiostatic operations. The effect of edge diffusion on the delamination process is evaluated. It is found that the diffusion from edge leads to an earlier delamination initiation. The edge effect is significant for active disks with a small aspect ratio, but negligible for the case of large aspect ratio. The edge diffusion is weaker in the potentiostatic operation than in the galvanostatic operation.

关键词： Lithium-ion battery · Thin film electrode · De-lamination · Diffusion

Structural Synthesis of Parallel Mechanisms with High Rotational Capability

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 73-83页

作者： Xiao-Dong Jin Yue-Fa Fang sheng guo Hai-Bo Qu School of Mechanical Electronic and Control EngineeringBeijing

Most parallel mechanisms(PMs) encountered today have a common disadvantage, i.e., their low rotational *** order to develop PMs with high rotational capability, a family of novel manipulators with one or two dimensional rotations is proposed. The planar one-rotational one-translational(1 R1 T) and one-rotational two-translational(1 R2 T)PMs evolved from the crank-and-rocker mechanism(CRM) are presented by means of Lie group theory. A spatial 2 R1 T PM and a 2 R parallel moving platform with bifurcated large-angle rotations are proposed by orthogonal combination of the RRRR limbs. According to the product principle of the displacement group theory, a hybrid 2 R3 T mechanism in possession of bifurcated motion is obtained by connecting the 2 R parallel moving platform with a parallel part, which is constructed by four 3 T1 R kinematic chains. The presented manipulators possess high rotational capability. The proposed research enriches the family of spatial mechanisms and the construction method provides an instruction to design more complex mechanisms.

关键词： Parallel mechanism Rotational capability Lie group theory Bifurcated motion Hybrid mechanism

Design of a novel side-mounted leg mechanism with high flexibility for a multi-mission quadruped earth rover BJTUBOT

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Frontiers of Mechanical Engineering 2023年第2期18卷 115-142页

作者： Yifan WU sheng guo Luquan LI Lianzheng NIU Xiao LI School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

Earth rover is a class of emerging wheeled-leg robots for nature *** present,few methods for these robots’leg design utilize a side-mounted spatial parallel ***,this paper presents a complete design process of a novel 5-degree-of-freedom(5-DOF)hybrid leg mechanism for our quadruped earth rover ***,a general approach is proposed for constructing the novel leg ***,by evaluating the basic locomotion task(LT)of the rover based on screw theory,we determine the desired motion characteristic of the sidemounted leg and carry out its two feasible *** regard to the synthesis method of the parallel mechanism,a family of concise hybrid leg mechanisms using the 6-DOF limbs and an L1F1C limb(which can provide a constraint force and a couple)is *** verifying the motion characteristics of this kind of leg,we select a typical(3-UPRU&RRRR)&R mechanism and then analyze its kinematic model,singularities,velocity mapping,workspace,dexterity,statics,and kinetostatic ***,the virtual quadruped rover equipped with this innovative leg mechanism is *** basic and specific LTs of the rover are demonstrated by simulation,which indicates that the flexibility of the legs can help the rover achieve multitasking.

关键词： design synthesis parallel mechanism hybrid leg mechanism screw theory quadruped robot

Uptake and accumulation of phenanthrene and pyrene in spiked soils by Ryegrass(Lolium perenne L.)

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Journal of Environmental Sciences 2005年第5期17卷 817-822页

作者： XU sheng-you CHEN Ying-xu LIN Qi WU Wei-xiang XUE sheng-guo SHEN Chao-feng Department of Environmental Engineering Zhejiang University Hangzhou 310029 China Department of Resource and Environment Huangshan University Huangshan 245000 China

Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors（BCFs） of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots （0.58-2.28）. BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L.

关键词： phytoremediation polycyclic aromatic hydrocarbons(PAHs) phenanthrene and pyrene uptake and accumulation

Algorithm of the Real-Time Extraction Image for Vehicle

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Wuhan University Journal of Natural Sciences 2000年第2期5卷 178-180页

作者： LIU Quan HUANG guo sheng Wuhan University of Technology College of Information Engineering Wuhan China (GRID:grid.162110.5) (ISNI:***)

An algorithm applied to a real-time extraction image of vehicle is introduced. The algorithm include an image processing with a binarzation method, image grab for a vehicle with high speed, character isolator one by one, and neural network algorithm. The techniques include vehicles sensing, image garb control, vehicle license location, lighting and optic character recognition. The system is much more robust and faster than the traditional thresholding method.

关键词： Key words image processing target extraction binarization neural network

Synergetic effects of Bi^(5+)and oxygen vacancies in Bismuth(Ⅴ)-rich Bi_(4)O_(7)nanosheets for enhanced near-infrared light driven photocatalysis

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Journal of Materials Science & Technology 2021年第26期85卷 1-10页

作者： Jin Liu sheng guo Hongzhang Wu Xinlei Zhang Jun Li Kun Zhou Henan Key Laboratory of Rare Earth Functional Materials Zhoukou Normal UniversityZhoukou 466001PR China Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052PR China School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430205PR China Environmental Process Modelling Centre Nanyang Environment and Water Research InstituteNanyang Technological University1 CleanTech Loop637141Singapore School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang Avenue639798Singapore

The appropriate energy level position of photocatalysts dominates the photocatalytic redox reaction and utilization efficiency of solar energy for wastewater ***,we report a near-infrared(NIR)light driven Bi^(5+)-rich Bi407 photocatalyst,achieving a greatly enhanced photocatalytic activity for pollutant removal compared with Bi3+-replenished *** functional theory calculations show the formation of an intermediate band in the Bi_(4)O_(7)structure because of the hybridization of O 2p and Bi 4s *** formation of the intermediate band not only narrows the band gap but also improves the optical absorption property and separation efficiency of the photoinduced *** existence of the oxygen vacancies(OVs)in the Bi_(4)O_(7)nanosheets ensures high carriers’concentration,which is verified by the Hall effect *** synergetic effects of the OVs and Bi^(5+)greatly accelerate the separation efficiency of the photogenerated ***,the Bi_(4)O_(7)nanosheets exhibit enhanced NIR light driven photocatalytic activity for the degradation of rhodamine B and ciprofloxacin compared with the bulk *** study paves the way to the design of highly efficient NIR light-responsive Bi-based photocatalysts for environmental purification.

关键词： Bi_(4)O_(7)nanosheets Near-infrared light Oxygen vacancies Charge separation Photocatalysis