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China Ocean Engineering 2018年第5期32卷 524-535页

作者： WANG Li-xian DENG Zheng-zhi WANG Chen WANG peng Key Laboratory of High Performance Ship Technology (Wuhan University of Technology) Ministry of Education Departments of Naval Architecture Ocean and Structural EngineeringSchool of TransportationWuhan University of Technology Institute of Port Coastal and Offshore EngineeringOcean CollegeZhejiang University

Based on linear water-wave theory, this study investigated the scattering of oblique incident water waves by two unequal surface-piercing thin vertical rigid plates with stepped bottom topography. By using the matched eigenfunction expansion method and a least square approach, the analytical solutions are sought for the established boundary value problem. The effects of the incidence angle, location of step, depth ratio of deep to shallow waters,and column width between two plates, on the reflection coefficients, the horizontal wave forces acting on the two plates, and the mean surface elevation between the two plates, are numerically examined under a variety of wave conditions. The results show that the existence of the stepped bottom between two plates considerably impacts the hydrodynamic performances of the present system. It is found that the effect of stepped bottom on the reflection coefficient of the present two-plate structure is evident only with waves of the low dimensionless ***, the influence of the step location on the hydrodynamic performance of the present two-plate structure is slight if the step is placed in between the two plates.

关键词： stepped bottom topography two unequal thin vertical rigid plates oblique water waves reflection coefficient wave force

Breather molecules and localized interaction solutions in the(2+1)-dimensional BLMP equation

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Communications in Theoretical Physics 2021年第12期73卷 69-77页

作者： Jiaxin Qi Hongli An peng jin College of Sciences Nanjing Agricultural UniversityNanjing210095China

The(2+1)-dimensional Boiti-Leon-Manna-Pempinelli(BLMP)equation is an important integrable *** this paper,we obtain the breather molecule,the breather-soliton molecule and some localized interaction solutions to the BLMP *** particular,by employing a compound method consisting of the velocity resonance,partial module resonance and degeneration of the breather techniques,we derive some interesting hybrid solutions mixed by a breather-soliton molecule/breather molecule and a lump,as well as a bell-shaped soliton and *** to the lack of the long wave limit,it is the first time using the compound degeneration method to construct the hybrid solutions involving a *** dynamical behaviors and mathematical features of the solutions are analyzed theoretically and *** method introduced can be effectively used to study the wave solutions of other nonlinear partial differential equations.

关键词： Boiti-Leon-Manna-Pempinelli equation module resonance velocity resonance solutions breather molecules interaction solutions

One-dimensional dynamic equations of a piezoelectric semiconductor beam with a rectangular cross section and their application in static and dynamic characteristic analysis

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Applied Mathematics and Mechanics(English Edition) 2018年第5期39卷 685-702页

作者： peng LI Feng jin Jianxun MA School of Human Settlements and Civil Engineering Xi'an Jiaotong University State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University

Within the framework of continuum mechanics, the double power series ex- pansion technique is proposed, and a series of reduced one-dimensional （1D） equations for a piezoelectric semiconductor beam are obtained. These derived equations are universal, in which extension, flexure, and shear deformations are all included, and can be degen- erated to a number of special cases, e.g., extensional motion, coupled extensional and flexural motion with shear deformations, and elementary flexural motion without shear deformations. As a typical application, the extensional motion of a ZnO beam is analyzed sequentially. It is revealed that semi-conduction has a great effect on the performance of the piezoelectric semiconductor beam, including static deformations and dynamic be- haviors. A larger initial carrier density will evidently lead to a lower resonant frequency and a smaller displacement response, which is a little similar to the dissipative effect. Both the derived approximate equations and the corresponding qualitative analysis are general and widely applicable, which can clearly interpret the inner physical mechanism of the semiconductor in the piezoelectrics and provide theoretical guidance for further experimental design.

关键词： piezoelectric semiconductor beam reduced one-dimensional (1D) equation,double power series expansion technique stress relaxation initial carrier density

Theoretical and Experimental Study on Tension–Torsion Coupling Vibration for Time-Varying Elevator Traction System

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Acta Mechanica Solida Sinica 2023年第6期36卷 899-913页

作者： peng Xu Qifeng peng Fusong jin Jianghong Xue Hong Yuan MOE Key Laboratory of Disaster Forecast and Control in Engineering School of Mechanics and Construction EngineeringJinan UniversityGuangzhou 51063China University of Health and Rehabilitation Sciences Qingdao 266071China School of Architectural Engineering Guangzhou Institute of Science and TechnologyGuangzhou 510540China Qingdao Xinghua Intelligent Equipment Co. Ltd.Qingdao 266114China

Elevators used in ultra-high buildings are prone to vibrating due to their ultra-long traction ropes,which significantly affects the comfort and safety of high-speed ***,vibration of the elevator has always been a topic of research *** paper presents a theoretical model for analyzing the tension–torsion coupling vibration of the time-varying elevator traction *** constitutive relations with the tension–torsion coupling effect of the wire rope are reduced by analyzing the deformation mechanism of the spiral winding wire *** on Hamilton’s principle,the equations of motion and corresponding boundary conditions for the tension–torsion coupling vibration of the elevator traction system are *** Galerkin method is employed to account for the influence of nonlinear boundary conditions and to transform the equations of motion into discrete ones with variable coefficients of time,which are solved using the Newmark-β*** accuracy of the proposed model is justified by the good agreement between theoretical predictions and experimental results,following which,the influence of the operation status and structural parameters of the elevator traction system on its vibration performance is discussed in detail.

关键词： Elevator traction system Wire rope Tension–torsion vibration Time-varying

Preparation, characterization, and adsorption-photocatalytic activity of nano TiO_2 embedded in diatomite synthesis materials

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Rare Metals 2017年第12期36卷 987-991页

作者： Ya-Li Zhang jing Yang xian-jin Yu School of Chemical-Engineering Shandong University of Technology Zibo 255049 China

Nano TiOembedded in diatomite(NTED)synthesis materials were prepared by a sol-gel method in absolute ethyl alcohol suspension. NTED synthesis materials have a higher specific surface area and larger pore volume using micromeritics ASAP 2020. The result of characterization was measured by X-ray diffraction(XRD),Fourier transform infrared(FT-IR) spectroscopy, scanning electron microscope(SEM), and energy dispersive spectroscopy(EDS). The cyanide wastewater was employed to evaluate the adsorption capacity and photocatalytic activity of prepared NTED synthesis materials. The better photocatalytic activity and adsorption capacity of NTED synthesis materials are attributed to their high surface area and higher UV absorption intensity for the cyanide wastewater.

关键词： Nano TiO_2 Diatomite(NTED) Embedded Adsorption Photocatalysis

Structures of sodium vanadate solution under different conditions

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Rare Metals 2018年第1期37卷 59-65页

作者： Ya-Li Zhang Li-Qun Yang xian-jin Yu School of Chemical Engineering Shandong University of Technology

Combined with Fourier transform infrared spectroscopy（FTIR） analysis of sodium vanadate solution,the relationship between conductivity and structure was investigated by measuring the electric conductivity of the solution under different alkali concentrations and molar ratios of NaOH to V2O5. Results suggest that the polymerization vanadium acid radical ions gradually transform into monomer with the solution diluting. When the solution is diluted to a certain extent,only the vanadium acid radical ion with V-OH chemical bond exists in the solution. At NaOH concentration of below 105.21 g·L^（-1）,the vanadate anions mainly exist in the form of vanadium acid radical ion with V-OH chemical bond and the ion transference number is approximately from 0.58 to 0.82. In the medium NaOH concentration range of 105.21-117.03 g·L^（-1）, the vanadate anions mostly exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds and the ion transference number is approximately 3.29. At NaOH concentration of above 117.03 g·L^（-1）, vanadate anions exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds.

关键词： Sodium vanadate solution Electric conductivity Migration number Infrared spectroscopy

Novel combinatorial algorithm for the problems of fuzzy grey multi-attribute group decision making

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Journal of Systems Engineering and Electronics 2007年第4期18卷 774-780页

作者： Rao Congjun Xiao Xinping peng jin Coll. of Mathematics and Information Science Huanggang Normal Univ. Huanggang 438000 P. R. China School of Science Wuhan Univ. of Technology Wuhan 430063 P. R. China

To study the fuzzy and grey information in the problems of multi-attribute group decision making, the basic concepts of both fuzzy grey numbers and grey interval numbers are given firstly, then a new model of fuzzy grey multi-attribute group decision making based on the theories of fuzzy mathematics and grey system is presented. Furthermore, the grey interval relative degree and deviation degree is defined, and both the optimistic algorithm of the grey interval relational degree and the algorithm of deviation degree minimization for solving this new model are also given. Finally, a decision making example to demonstrate the feasibility and rationality of this new method is given, and the results by using these two algorithms are uniform.

关键词： multi-attribute group decision making fuzzy grey number grey interval relational degree deviation degree

Mg-based absorbable membrane for guided bone regeneration(GBR): a pilot study

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Rare Metals 2019年第6期38卷 577-587页

作者： Wei peng Jun-Xiu Chen xian-Feng Shan Yi-Chuan Wang Fan He Xue-jin Wang Li-Li Tan Ke Yang Department of Stomatology Affiliated Zhongshan Hospital of Dalian UniversityDalian 116001China Medical School of Dalian University Dalian 116622China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

A novel calcium-phosphate(Ca–P)-coated magnesium(Mg) membrane used for guided bone regeneration(GBR) was *** microstructural characterization, electrochemical test, immersion test,fluorescence labeling analysis and histopathological evaluation were carried *** results showed that Ca–P coating could obviously improve the corrosion resistance of the pure Mg *** in vivo results showed that Mg membrane coated with Ca–P would take 8 weeks to be completely ***, Mg membrane was completely absorbed within 1 *** evaluation showed that the Ca–P-coated Mg membranes were significantly better than Ti membranes at the early implantation time(4 weeks), and with the time prolonging,the performance of the coated Mg membrane was not as good as pure Ti membranes(but still better than blank group) at 8 and 12 *** coated biodegradable Mg membrane had a good promising application in *** further studies have to be done to further decrease the degradation rate of pure Mg membrane.

关键词： Bone defect Guided bone regeneration Ca–P-coated magnesium(Mg) membrane Bioabsorbable membrane

Inverse Curvature Flows of Rotation Hypersurfaces

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1692-1708页

作者： Yu Han jin xian Feng WANG Yong WEI School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

We consider the inverse curvature flows of smooth,closed and strictly convex rotation hypersurfaces in space forms M_(κ)^(n+1)with speed function given by F^(-α),whereα∈(0,1]forκ=0,-1,α=1 forκ=1 and F is a smooth,symmetric,strictly increasing and 1-homogeneous function of the principal curvatures of the evolving *** show that the curvature pinching ratio of the evolving hypersurface is controlled by its initial value,and prove the long time existence and convergence of the *** second derivatives conditions are required on F.

关键词： Inverse curvature flow rotation hypersurface

Frequency and Correlation of Nearest Neighboring Nucleotides in Human Genome

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Chinese Journal of Chemical Physics 2009年第1期22卷 27-33页

作者： Neng-zhi jin Zi-xian Liu Wen-yuan Qiu Department of Chemistry State Key Laboratory of Applied Organic Chemistry Lanzhou Universiry. Lanzhou 730000 China

Zipf＇s approach in linguistics is utilized to analyze the statistical features of frequency and correlation of 16 nearest neighboring nucleotides （AA, AC, AG, …, TT） in 12 human chro- mosomes （Y, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, and 12）. It is found that these statistical features of nearest neighboring nucleotides in human genome：（i） the frequency distribution is a linear function, and （ii） the correlation distribution is an inverse function. The coefficients of the linear function and inverse function depend on the GC content. It proposes the correlation distribution of nearest neighboring nucleotides for the first time and extends the descriptor about nearest neighboring nueleotides.

关键词： Zipf's law Nearest neighboring nucleotide Frequency distribution Correlation distribution