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Transfer Path Contribution to Floor Vibration of Metro Vehicles Based on Operational Transfer Path Analysis Method

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 228-238页

作者： Laixian Peng Jian Han Jiaxing nie Xinbiao xiao Caiying Mi School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China Southwest Technology and Engineering Research Institute Chongqing 400039China State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China

Operational transfer path analysis(OTPA)is an advanced vibration and noise transfer path identification and contribution evaluation ***,the application of OTPA to rail transit vehicles considers only the excitation amplitude and ignores the influence of the excitation *** study considers the influence of the excitation amplitude and phase,and analyzes the contribution of the secondary suspension path to the floor vibration when the metro vehicle runs at 60 km/h,using an analysis based on the OTPA *** results show that the vertical direction of the anti-rolling torsion bar area provides the maximum contribution to the floor vibration,with a contribution of 22.1%,followed by the longitudinal vibration of the air spring area,with a contribution of 17.1%.Based on the contribution analysis,a transfer path optimization scheme is proposed,which may provide a reference for the optimization of the transfer path of metro vehicles in the future.

关键词： OTPA Secondary suspension Contribution analysis Transfer path optimization scheme Metro vehicles

Self-sacrificial templating synthesis of flower-like nickel phyllosilicates and its application as high-performance reinforcements in epoxy nanocomposites

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Frontiers of Chemical Science and Engineering 2022年第4期16卷 484-497页

作者： Jinian Yang Xuesong feng Shibin nie Yuxuan Xu Zhenyu Li School of Materials Science and Engineering State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal MinesAnhui University of Science and TechnologyHuainan 232001China School of Safety Science and Engineering State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal MinesAnhui University of Science and TechnologyHuainan 232001China

The nanocomposites of flower-like nickel phyllosilicate particles incorporated into epoxy resin were fabricated via an in-situ mixing *** flower-like nickel phyllosilicate particles were firstly synthesized using a mild self-sacrificial templating method,and the morphology and lamellar structure were examined *** properties of mechanical,thermal and tribological responses of epoxy nanocomposites were *** was demonstrated that adequate flower-like nickel phyllosilicate particles dispersed well in the matrix,and the nanocomposites displayed enhanced tensile strength and elastic modulus but decreased elongation at break as *** addition,friction coefficient and wear rate were increased first and then decreased along with the particle content,and showed the lowest values at a mass fraction of 5%.Nevertheless,the incorporated flower-like nickel phyllosilicate particles resulted in the continuously increasing thermal stability of epoxy resin(EP)*** study revealed the giant potential of flower-like particles in preparing high-quality EP nanocomposites.

关键词： nickel phyllosilicate flow-like structure mechanical property thermal stability tribological performance

Characterization of suspended solids and particle-bound heavy metals in a first flush of highway runoff

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1567-1575页

作者： Fa-hui nie Tian LI Hai-feng YAO Man feng Guang-kai ZHANG State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Institute of Environment Engineering Research East China Jiaotong University Nanchang 330013 China

To investigate the dynamic characteristics of total suspended solids (TSS) and their particle-bound heavy metals in a first flush, the runoff sampling together with its flow rate measuring was conducted for three rainfall events at outfalls of highway in Shanghai from June to September 2007. Field samples were analyzed to determine the concentrations of TSS and particle-bound heavy metals, such as Zn, Pb, and Cu. Results show that the wash off behavior of TSS under varying runoff rate condition can be explained by different antecedent dry weather period (ADWP). Contribution of fine fraction (45 μm). When the runoff flow increased obviously, a significant contribution of the coarse fraction was observed for a certain rainfall events with long antecedent dry weather condition. The changes of total metals concentration and particle-bound metal concentrations were strongly dependent on the TSS variation. TSS was generally well correlated with most particulate-bound heavy metals. Of the heavy metals, the concentration of Zn was found considerably high and that of Pb was significantly low at North Zhongshan 2 Road, in Shanghai, China, but they are still within the range reported in the literature. Fluctuation of heavy metal contents in the coarse fraction during a first flush period was more significant compared with that in the fine fraction. The results will assist in the development of effective control strategies to minimize heavy metals and solids in highway runoff.

关键词： Heavy metals Highway runoff First flush Suspended solids (SS)

Immunology of Stem Cells and Cancer Stem Cells

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Cellular & Molecular Immunology 2007年第3期4卷 161-171页

作者： xiao-feng Yang Department of Pharmacology Temple University School of Medicine Philadelphia PA 19140 USA

The capacity of pluri-potent stem cells to repair the tissues in which stem cells reside holds great promise in development of novel cell replacement therapeutics for treating chronic and degenerative diseases. However, numerous reports show that stem cell therapy, even in an autologous setting, triggers lymphocyte infiltration and inflammation. Therefore, an important question to be answered is how the host immune system responds to engrafted autologous stem cells or allogeneous stem cells. In this brief review, we summarize the progress in several related areas in this field, including some of our data, in four sections：（1） immunogenicity of stem cells; （2） strategies to inhibit immune rejection to allograft stem cells; （3） immune responses to cancer stem cells; and （4） mesenchymal stem cells in immune regulation. Improvement of our understanding on these and other aspects of immune system-stem cell interplay would greatly facilitate the development of stem cell-based therapeutics for regenerative purposes. Cellular ＆ Molecular Immunology.

关键词： immunogenicity stem cell therapy cancer stem cells stimulation-responsive splicing model

Decorated zeolites for chemoselective alkyne/olefin separations

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Science China Chemistry 2020年第9期63卷 1177-1178页

作者： feng-Shou xiao Department of Chemistry Zhejiang UniversityHangzhou 310007China

Light olefins,such as ethylene,propylene,and 1,3-butadiene,are basic chemical raw materials with increasing global demand of approaching 400 million metric tons per *** the industrial production of light olefins,traces of alkyne impurities are co-produced and will show great impacts on the polymerization and subsequent processing of *** purification of olefins is therefore regarded as one of the most important and largest chemical separation processes[1].

关键词： separation approaching propylene

Tunable optical second-order sideband effects in a parity-time symmetric optomechanical system

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 51-58页

作者： Xing xiao QingHong Liao NanRun Zhou WenJie nie YongChun Liu Department of Electronic Information Engineering Nanchang UniversityNanchang 330031China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsFrontier Science Center for Quantum InformationTsinghua UniversityBeijing 100084China Department of Applied Physics East China Jiaotong UniversityNanchang 330013China

We theoretically investigate the optical second-order sideband generation(OSSG)in an optical parity-time(PT)symmetric system,which consists of a passive cavity trapping the atomic ensemble and an active *** with the double-passive system,it is found that near the exceptional point(EP),the efficiency of the OSSG increases sharply not only for the blue probepump detuning resonant case but also for the red *** experimentally achievable parameters,we study the effect of the atomic ensemble on the efficiency of the OSSG in the PT-symmetric *** numerical results show that the efficiency of the OSSG is 30%higher than that of the first-order sideband,which is realized easily by simultaneously modulating the atom-cavity coupling strength and ***,the efficiency of the OSSG can also be tuned effectively by the pump power,and the efficiency is robust when the pump power is strong *** study may have some guidance for modulating the nonlinear optical properties and controlling light propagation,which may stimulate further applications in optical communications.

关键词： second-order sideband effects parity-time symmetry optomechanical system

Symplectic system based analytical solution for bending of rectangular orthotropic plates on Winkler elastic foundation

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Acta Mechanica Sinica 2011年第6期27卷 929-937页

作者： Wei-An Yao xiao-Fei Hu feng xiao State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology 116024 Dalian China Department of Computer Science Dalian Medical University 116044 Dalian China

This paper analyses the bending of rectangular orthotropic plates on a Winkler elastic *** definition of symplectic inner product and symplectic space formed by generalized displacements establish dual variables and dual equations in the symplectic *** operator matrix of the equation set is proven to be a Hamilton operator *** of variables and eigenfunction expansion creates a basis for analyzing the bending of rectangular orthotropic plates on Winkler elastic foundation and obtaining solutions for plates having any boundary *** is discussion of symplectic eigenvalue problems of orthotropic plates under two typical boundary conditions,with opposite sides simply supported and opposite sides *** equations of eigenvalues and symplectic eigenvectors in analytical form *** solutions using two examples are presented to show the use of the new methods described in this *** verify the accuracy and convergence,a fully simply supported plate that is fully and simply supported under uniformly distributed load is used to compare the classical Navier method,the Levy method and the new *** show that the new technique has good accuracy and better convergence speed than other methods,especially in relation to internal forces.A fully clamped rectangular plate on Winkler foundation is solved to validate application of the new methods,with solutions compared to those produced by the Galerkin method.

关键词： Orthotropic plate Symplectic space Winklerelastic foundation Analytical solution

Self-adjusting entropy-stable scheme for compressible Euler equations

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Chinese Physics B 2015年第2期24卷 16-22页

作者：程晓晗聂玉峰封建湖 Luo xiao-Yu 蔡力 School of Science Northwestern Polytechnical University School of Science Chang'an University School of Mathematics and Statistics University of Glasgow

In this work,a self-adjusting entropy-stable scheme is proposed for solving compressible Euler *** entropy-stable scheme is constructed by combining the entropy conservative flux with a suitable diffusion *** entropy has to be preserved in smooth solutions and be dissipated at *** achieve this,a switch function,which is based on entropy variables,is employed to make the numerical diffusion term be automatically added around *** resulting scheme is still entropy-stable.A number of numerical experiments illustrating the robustness and accuracy of the scheme are *** these numerical results,we observe a remarkable gain in accuracy.

关键词： compressible Euler equations entropy-stable scheme switch function

Properties of Proton Transfer in Hydrogen-Bonded Systems at Finite Temperature

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Communications in Theoretical Physics 2002年第10期38卷 407-414页

作者： PANG xiao-feng Institute of Life Science and Technology University of Electronic Science and Technology Chengdu 610054 China International Center for Materials Physics the Chinese Academy of Sciences Shenyang 110015 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China

The properties of proton transfer along hydrogen-bonded molecular systems are studied at finite temperature. The dynamic equations of the proton transport along the systems are obtained by using a completely quantummechanics method. From the dynamic equations and its soliton solutions we find out specific heat arising from the motionof solitons in the systems with finite temperature and the critical temperature of the soliton in the protein molecules,which is about 318 K. This shows that we can continuously study some biological phenomena in the living systems bythis model.

关键词： proton transfer, hydrogen bond, critical temperature, specific heat