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足尺单柱桥梁模型爆破振动响应

长安大学学报（自然科学版） 2017年第4期37卷 105-111页

作者：王国波胡俊季杉谢伟平王礼武汉理工大学道路桥梁与结构工程湖北省重点实验室湖北武汉430070 武汉理工大学土木工程与建筑学院湖北武汉430070

为了研究高架桥梁桥墩爆破引起的振动传播规律及其对周边的影响,采用现场试验和数值分析相结合的方法开展相关研究。首先在表层无混凝土的土层上选取有代表性的桥墩,按相同尺寸和配筋在试验场进行浇注,修建2个独立墩柱模型进行单柱爆破... 详细信息

为了研究高架桥梁桥墩爆破引起的振动传播规律及其对周边的影响,采用现场试验和数值分析相结合的方法开展相关研究。首先在表层无混凝土的土层上选取有代表性的桥墩,按相同尺寸和配筋在试验场进行浇注,修建2个独立墩柱模型进行单柱爆破试验及现场实测;然后利用LSDYNA软件建立单柱数值计算模型,对爆破试验进行了详细的拟合分析,给出了各测点的振动速度时程曲线及其频谱曲线,并从振动幅值和频谱特性2个方面分析了爆破振动效应;最后将计算结果与试验结果进行对比分析。研究结果表明:随着测点与爆源之间距离的增加,各方向速度响应逐渐衰减,其中竖向速度衰减最快,测点各方向速度为0.05~1.36cm/s,其中竖向速度最大,水平切向速度最小;各方向振动频率为15~20Hz,与周边一般建筑的基频相差较大,爆破振动在空气中衰减迅速,表明爆破自身引起的振动效应影响较小;数值拟合分析结果与试验结果的动力响应规律基本一致,表明采取的动力有限元计算分析方法能较好地模拟爆破过程,可利用该方法对整个高架桥的爆破过程进行初步分析,从而为最终的爆破方案提供合理依据。

关键词：桥梁工程足尺模型试验爆破振动响应动力有限元

Antiviral therapy for hepatitis B virus infection is beneficial for the prognosis hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 1-9页

作者： Hui Wan Yu-Xin Zhang Guan-Yue shan jun-Ya Cheng Duan-Rui Qiao Yi-Ying Liu Wen-Na Shi Hai-jun Li Institute of Translational Medicine The First Hospital of Jilin UniversityChangchun 130061Jilin ProvinceChina Department of Bioengineering Pharmacy School of Jilin UniversityChangchun 130061Jilin ProvinceChina Institute of Liver Diseases Institute of Translational MedicineThe First Hospital of Jilin UniversityChangchun 130061Jilin ProvinceChina

In this editorial,we comment on the article by Mu et al,published in the recent issue of the World Journal of Gastrointestinal *** pay special attention to the immune tolerance mechanism caused by hepatitis B virus(HBV)infection,the pathogenesis of hepatocellular carcinoma(HCC),and the role of antiviral therapy in treating HCC related to HBV *** infection leads to systemic innate immune tolerance by directly inhibiting pattern recognition receptor recognition and antiviral signaling pathways,as well as by inhibiting the immune functions of macrophages,natural killer cells and dendritic *** addition,HBV leads to an immunosuppressive cascade by expressing inhibitory molecules to induce exhaustion of HBV-specific cluster of differentiation 8+T cells,ultimately leading to long-term viral *** loss of immune cell function caused by HBV infection ultimately leads to ***-term antiviral therapy can improve the prognosis of patients with HCC and prevent tumor recurrence and metastasis.

关键词： Hepatitis B virus Hepatocellular carcinoma Hepatitis B virus-DNA Immune tolerance Antiviral therapy

The convergence on spectrum of sample covariance matrices for information-plus-noise type data

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Applied Mathematics(A Journal of Chinese Universities) 2012年第2期27卷 181-191页

作者： xie jun-shan Department of Mathematics Zhejiang UniversityHangzhou 310027China College of Mathematics and Information Henan UniversityKaifeng 475000China

In this paper,we consider the limiting spectral distribution of the information-plus-noise type sample covariance matrices Cn=1/N（Rn＋σXn）（Rn＋σXn）,under the assumption that the entries of Xn are independent but non-identically distributed random *** is proved that,almost surely,the empirical spectral distribution of Cn converges weakly to a non-random distribution whose Stieltjes transform satisfies a certain *** result extends the previous one with the entries of Xn are *** varibles to a more general *** proof of the result mainly employs the Stein equation and the cumulant expansion formula of independent random variables.

关键词： limiting spectral distribution sample covariance matrix Stieltjes transform.

Novel high torque bearingless two-sided rotary ultrasonic motor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 786-792页

作者： LI Xia CHEN Wei-shan xie Tao LIU jun-kao Department of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

Applications are limited at present because the currently available ultrasonic motors (USMs) do not provide suffi-ciently high torque and power. The conventional travelling-wave USM needs the bearing to support, which required lubricant. To solve the above problem, a bearingless travelling-wave USM is designed. First, a novel structure of the two-sided USM consisting of a two-sided teeth stator and two disk-type rotors is designed. And the excitation principle of the two-sided travelling-wave USM is analyzed. Then, using ANSYS software, we set up the model of the stator to predict the excitation frequency and modal response of the stator. The shape of the vibration mode was obtained. Last, the load characteristics of the USM are measured using ex-perimental method. The maximum stall torque and the no-load speed were obtained. The results showed that the characteristics of the two-sided USM are better than those of the conventional one-sided USM.

关键词： Two-sided Ultrasonic motor (USM) Piezoelectric motor Travelling-wave Bearingless

Coseismic Coulomb failure stress changes caused by the 2017 M7.0 Jiuzhaigou earthquake,and its relationship with the 2008 Wenchuan earthquake

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Science China Earth Sciences 2017年第12期60卷 2181-2189页

作者： shan Bin ZHENG Yong LIU ChengLi xie Zujun KONG jun Hubei Subsurface Multi-scale Imaging Key Laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China Sichuan Earthquake Administration Chengdu 610041China

On August 8, 2017, a M7.0 earthquake occurred in Jiuzhaigou County, Sichuan Province, China, resulting in significant casualties and property damage. Therefore, it is critical to identify the areas of potential aftershocks before reconstruction and re-settling people to avoid future disasters. Based on the elastic dislocation theory and a multi-layered lithospheric model, we calculate the Coulomb failure stress changes caused by the Wenchuan and Jiuzhaigou earthquakes, discuss the relationship between the Mw7.9 Wenchuan and M7.0 Jiuzhaigou earthquakes, and analyze the influence of the aftershock distribution and stress changes on the major faults in this region caused by the Jiuzhaigou earthquake. The co-and post-seismic stress changes caused by the Wenchuan earthquake significantly increased the stress accumulation at the hypocenter of the Jiuzhaigou earthquake. Therefore,the occurrence of the Jiuzhaigou earthquake was probably stimulated by the Wenchuan earthquake. The aftershock distribution is well explained by the co-seismic stress changes of the Jiuzhaigou earthquake. The stress accumulation and corresponding seismic hazard on the Maqu-Heye segment of the East Kunlun fault and the northern extremity of the Huya fault has been further increased by the Jiuzhaigou earthquake.

关键词： Jiuzhaigou earthquake Wenchuan earthquake Seismic hazard Coulomb failure stress

Parametrized post-Newtonian secular transit timing variations for exoplanets

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Research in Astronomy and Astrophysics 2013年第10期13卷 1231-1239页

作者： shan-shan Zhao Yi xie Department of Astronomy Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education

Ground-based and space-borne observatories used for studying exoplanet transits now and in the future will considerably increase the number of exoplanets known from transit data and the precision of the measured times of transit *** in the transit times can not only be used to infer the presence of additional planets,but might also provide opportunities to test the general theory of relativity in these *** build a framework for these possible tests,we extend previous studies on the observability of the general relativistic precessions of periastron in transiting exoplanets to variations in secular transit timing under parametrized post-Newtonian *** find that if one can measure the difference between observed and predicted variations of general relativistic secular transit timing to 1 s yr-1in a transiting exoplanet system with a Sun-like mass,a period of;day and a relatively small eccentricity of;.1,general relativity will be tested to the level of;%.

关键词： gravitation celestial mechanics planetary systems

Evaluation of the Protective Efficacy of a Fused OmpK/Omp22 Protein Vaccine Candidate against Acinetobacter baumannii Infection in Mice

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Biomedical and Environmental Sciences 2018年第2期31卷 155-158页

作者： GUO San jun REN shan xie Yong En The Research Institute of Immunology and Molecular Biology North Sichuan Medical College

Acinetobocter baumannfi （A. Baumannii） is an emerging opportunistic pathogen responsible for hospital-acquired infections, and which now constitutes a sufficiently serious threat to public health to necessitate the development of an effective vaccine. In this study, a recombinant fused protein named OmpK/Omp22 and two individual proteins OmpK and Omp22 were obtained using recombinant expression and Ni-affinity purification. Groups of BALB/c mice were immunized with these proteins and challenged with a clinically isolated strain of A. boumonnii. The bacterial load in the blood, pathological changes in the lung tissue and survival rates after challenge were evaluated. Mice immunized with OmpK/Omp22 fused protein provided significantly greater protection against A. boumonnfi challenge than those immunized with either of the two proteins individually. The results provide novel clues for future design of vaccines against A. boumonnii.

关键词： Evaluation of the Protective Efficacy of a Fused OmpK/Omp22 Protein Vaccine Candidate against Acinetobacter baumannii Infection in Mice

Ambient Temperature Living Radical Copolymerization of Styrene and Methyl Methacrylate with Sodium Hypophosphite as Reducing Agent

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Chinese Journal of Polymer Science 2015年第2期33卷 362-370页

作者：刘晓辉 Hui-na Li Fei-jun Zhang shan xie Zhan-jun Liu 李彦国 School of Materials Science and Engineering Tianjin Key Laboratory of Fiber Modification and Functional FiberTianjin Polytechnic University College of Pharmacy Hebei United University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

A facile, safe and economical reducing agent, sodium hypophosphite（Na H2PO2·H2O）, has been successfully employed for ambient temperature living radical copolymerization of styrene（St） and methyl methacrylate（MMA）. Such effective reducing agent significantly improved the reactivity of low reactive St monomers during the copolymerization, where the reactivity ratios of St and MMA were determined to be 0.50 and 0.36 by Finemann-Ross method. Thus the copolymerizations proceeded fast and showed typical living/controlled features, as evidenced by pseudo first-order kinetics of polymerization, linear increase in molecular weight versus monomer conversion, and low polydispersity index values. Effects of the concentration of reducing agent and the monomer feed ratio on the copolymerization were investigated in detail. Furthermore, gel permeation chromatography and 1H-NMR analyses as well as chain extension experiments confirmed the high chain-end functionality of the resultant copolymer.

关键词： Controlled/living radical copolymerization Sodium hypophosphite Ambient temperature Methyl methacrylate Styrene

Novel approach for determining the optimal axial preload of a simulating rotary table spindle system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 812-817页

作者： shan Xiao-biao xie Tao CHEN Wei-shan School of Mechatronics Engineering Harbin Institute of Technology Harbin 15001 China

This paper presents a new theoretical model to determine the optimal axial preload of a spindle system, for challenging the traditional method which relies heavily on experience of engineers. The axial preloading stiffness was treated as the sum of the spindle modal stiffness and the framework elastic stiffness, based on a novel concept that magnitude of preloads can be controlled by measuring the resonant frequency of a spindle system. By employing an example of a certain type of aircraft simulating rotary table, the modal stiffness was measured on the Agilent 35670A Dynamic Signal Analyzer by experimental modal analysis. The equivalent elastic stiffness was simulated by both finite element analysis in ANSYS? and a curve fitting in MATLAB?. Results showed that the static preloading stiffness of the spindle was 7.2125×107 N/m, and that the optimal preloading force was 120.0848 N. Practical application proved the feasibility of our method.

关键词： Three-axis simulating rotary table Axial position preload Stiffness Experimental modal analysis Finite elementanalysis