资源类型

期刊论文 54

年份

2023 3

2022 2

2021 4

2020 1

2019 3

2018 1

2017 5

2016 1

2015 1

2013 2

2012 3

2011 2

2010 3

2009 6

2008 3

2007 5

2006 3

2005 1

2004 1

2003 1

展开 ︾

关键词

Si/Al 比值 1

ZN-1阻尼橡胶材料 1

三塔悬索桥 1

二线隧道 1

交叉模态 1

交通导致振动 1

信号平稳化 1

关键构造 1

分步开挖 1

初始刚度 1

加权平均原则 1

化学键参数 1

半主动控制 1

卸荷 1

原子半径差比率 1

圆柱 1

多维减振 1

大块金属玻璃 1

大桥 1

展开 ︾

检索范围：

排序： 展示方式：

Joint slip investigation based on finite element modelling verified by experimental results on wind turbine lattice towers

Saleh YAGHOOBI, Ahmad SHOOSHTARI

《结构与土木工程前沿（英文）》 2018年 第12卷 第3期   页码 341-351 doi: 10.1007/s11709-017-0393-y

摘要：

Slippage corresponds to the relative displacement of a bolted joint subjected to shear loads since the construction clearance between the bolt shank and the bolthole at assembly can cause joint slip. Deflections of towers with joint slippage effects is up to 1.9 times greater than the displacements obtained by linear analytical methods. In this study, 8 different types of joints are modelled and studied in the finite element program, and the results are verified by the experimental results which have been done in the laboratory. Moreover, several types of joints have been modelled and studied and load-deformation curves have also been presented. Finally, joint slip data for different types of angles, bolt diameter and bolt arrangements are generated. Thereupon, damping ratios (z) for different types of connections are reported. The study can be useful to help in designing of wind turbine towers with a higher level of accuracy and safety.

关键词： Joint slip     cyclic loading     Finite element modelling     Experimental joint behavior     damping ratios (   

HTML PDF 收藏

Novel hierarchical yolk-shell

Xiqing Luo, Miaomiao Jiang, Kun Shi, Zhangxian Chen, Zeheng Yang, Weixin Zhang

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1322-1331 doi: 10.1007/s11705-021-2036-z

摘要： For high performance supercapacitors, novel hierarchical yolk-shell -Ni(OH) /Mn O microspheres were controllably synthesized using a facile two-step method based on the solvothermal treatment. The unique -Ni(OH) based yolk-shell microstructures decorated with numerous interconnected nanosheets and the hetero-composition features can synergistically enhance reactive site exposure and electron conduction within the microspheres, facilitate charge transfer between electrolyte and electrode materials, and release structural stress during OH chemisorption/desorption. Moreover, the Mn O sediments distributed over the -Ni(OH) microspheres can serve as an effective protective layer for electrochemical reactions. Consequently, when tested in 1 mol·L KOH aqueous electrolyte for supercapacitors, the yolk-shell -Ni(OH) /Mn O microspheres exhibited a considerably high specific capacitance of 2228.6 F·g at 1 A·g and an impressive capacitance retention of 77.7% after 3000 cycles at 10 A·g . The proposed -Ni(OH) /Mn O microspheres with hetero-composition and unique hierarchical yolk-shell microstructures are highly promising to be used as electrode materials in supercapacitors and other energy storage devices.

关键词：    

HTML PDF 收藏

Anti-β2GPI/β2GPI complexes induce platelet activation and promote thrombosis via p38MAPK: a pathway to targeted therapies

Wenjing Zhang, Caijun Zha, Xiumin Lu, Ruichun Jia, Fei Gao, Qi Sun, Meili Jin, Yanhong Liu

《医学前沿（英文）》 2019年 第13卷 第6期   页码 680-689 doi: 10.1007/s11684-018-0673-5

摘要： Anti- glycoprotein I (anti- GPI) antibodies are important contributors to the development of thrombosis. Anti- GPI antibody complexes with GPI are well known to activate monocytes and endothelial cells via the intracellular NF- B pathway with prothrombotic implications. By contrast, the interaction of anti- GPI/ GPI complexes with platelets has not been extensively studied. The p38 mitogen-activated protein kinase (MAPK) pathway has been recognized to be an important intracellular signaling pathway in the coagulation cascade and an integral component of arterial and venous thrombosis. The present study reveals that levels of anti- GPI/ GPI complexes in sera are positively associated with p38MAPK phosphorylation of platelets in thrombotic patients. Furthermore, SB203580 inhibits anti- GPI/ GPI complex-induced platelet activation. Thrombus formation decreased in mice after treatment with anti- GPI/ GPI complexes. In conclusion, p38MAPK may be a treatment target for anti- GPI antibody-associated thrombotic events.

关键词： anti-   

HTML PDF 收藏

Minimal residual disease-directed immunotherapy for high-risk myelodysplastic syndrome after allogeneic hematopoietic stem cell transplantation

Xiaodong Mo, Xiaohui Zhang, Lanping Xu, Yu Wang, Chenhua Yan, Huan Chen, Yuhong Chen, Wei Han, Fengrong Wang, Jingzhi Wang, Kaiyan Liu, Xiaojun Huang

《医学前沿（英文）》 2019年 第13卷 第3期   页码 354-364 doi: 10.1007/s11684-018-0665-5

摘要： The efficacy of minimal residual disease (MRD)-directed immunotherapy, including interferon- (IFN- ) treatment and chemotherapy plus granulocyte colony-stimulating factor-primed donor leukocyte infusion (chemo-DLI), was investigated in patients with high-risk myelodysplastic syndrome (MDS) who were MRD-positive after allogeneic hematopoietic stem cell transplantation (allo-HSCT). High-risk MDS patients who received non-T-cell-depleted allo-HSCT at the Peking University Institute of Hematology and were MRD-positive after allo-HSCT were studied ( =47). The MRD-positive status was considered if leukemia-associated aberrant immune phenotypes or Wilms’ tumor gene 1 expression is present in a single bone marrow sample. The cumulative incidence of the relapse and non-relapse mortality 2 years after immunotherapy were 14.5% and 21.4% ( =0.377) and 9.1% and 0.0% ( =0.985) for patients in the IFN- and chemo-DLI groups, respectively. The probability of disease-free and overall survival 2 years after immunotherapy were 76.4% and 78.6% ( =0.891) and 84.3% and 84.6% ( =0.972) for patients in the IFN- and chemo-DLI groups, respectively. Persistent MRD after immunotherapy was associated with poor survival. Thus, the MRD-directed immunotherapy was effective for patients with high-risk MDS who were MRD-positive after allo-HSCT, and the efficacy was comparable between chemo-DLI and IFN- treatment.

关键词： donor leukocyte infusion     hematopoietic stem cell transplantation     interferon-   

HTML PDF 收藏

Controlled synthesis of uniform silver nanowires with high aspect ratios in aqueous solutions of gemini

XU Jian, LIU Weijun, LIU Honglai, HU Ying

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 221-227 doi: 10.1007/s11705-007-0040-6

摘要： A simple solution-phase approach has been demonstrated for the large-scale synthesis of silver nanowires with diameters in the range of 15 25 nm, and lengths usually in the range of tens of micrometers. In the presence of gemini surfactant 1,3-bis(cetyldimethylammonium) propane dibromide (16-3-16), the growth of silver could be directed into a highly anisotropic mode to form uniform nanowires with aspect ratios up to about 2,000. X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), X-ray powder diffraction (XRD), electron diffraction (ED), and UV-vis absorption spectroscopy, were used to characterize the as-prepared silver nanowires, indicating the formation of a highly pure phase, good crystallinity, as well as a uniform diameter.

关键词： solution-phase     photoelectron spectroscopy     16-3-16     surfactant     transmission    

HTML PDF 收藏

Development of rocking constraint device with vertical damping capacity for three-dimensional base-isolated

《结构与土木工程前沿（英文）》 2023年 第17卷 第3期   页码 350-367 doi: 10.1007/s11709-022-0923-0

摘要： A new rocking constraint device (RCD) is developed for three-dimensional (3D) base-isolated frame structures by connecting a custom-designed cylinder pair to provide vertical damping with replaceable damping components installed outside the cylinders when the superstructure undergoes translational motion, and rocking constraint capacity when the superstructure is susceptible to rocking. Theoretical formulas for calculating the damping and rocking constraint stiffness of the RCD are proposed. Two series of sinusoidal loading tests are conducted at different loading frequencies and amplitudes to verify the damping and rocking constraint performance of the RCD. The test results show that the cylinder without orifices on its piston can provide the desired damping with a replaceable damping component, and that the RCD can effectively suppress rocking. Although the vertical stiffness of an individual cylinder is affected by the location of the replaceable damping component and loading frequency, the average vertical stiffness of the two cylinders, which determines the rocking constraint stiffness of the RCD, is independent of the two factors. Comparisons of the test and theoretical results indicate that the errors of the proposed formulas for calculating the damping and rocking constraint stiffness of the RCD do not exceed 12.9% and 11.0%, respectively.

关键词： three-dimensional isolation     rocking behavior     rocking constraint device     replaceable damping component     sinusoidal test    

HTML PDF 收藏

Approximation of structural damping and input excitation force

Mohammad SALAVATI

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 244-254 doi: 10.1007/s11709-016-0371-9

摘要： Structural dynamic characteristics are the most significant parameters that play a decisive role in structural damage assessment. The more sensitive parameter to the damage is the damping behavior of the structure. The complexity of structural damping mechanisms has made this parameter to be one of the ongoing research topics. Despite all the difficulties in the modeling of damping, there are some approaches like as linear and nonlinear models which are described as the energy dissipation throughout viscous, material or structural hysteretic and frictional damping mechanisms. In the presence of a mathematical model of the damping mechanisms, it is possible to estimate the damping ratio from the theoretical comparison of the damped and un-damped systems. On the other hand, solving the inverse problem of the input force estimation and its distribution to each SDOFs, from the measured structural responses plays an important role in structural identification process. In this paper model-based damping approximation method and a model-less structural input estimation are considered. The effectiveness of proposed methods has been carried out through analytical and numerical simulation of the lumped mass system and the results are compared with reference data. Consequently, high convergence of the comparison results illustrates the satisfactory of proposed approximation methods.

关键词： structural modal parameters     damping identification method     input excitation force identification     Inverse problem    

HTML PDF 收藏

Variable stiffness and damping magnetorheological isolator

Yang ZHOU, Xingyu WANG, Xianzhou ZHANG, Weihua LI

《机械工程前沿（英文）》 2009年 第4卷 第3期   页码 310-315 doi: 10.1007/s11465-009-0039-4

摘要： This paper presents the development and characterization of a magnetorheological (MR) fluid-based variable stiffness and damping isolator. The prototype of the MR fluid isolator is fabricated, and its dynamic behavior is measured under various applied magnetic fields. The parameters of the model under various magnetic fields are identified, and the dynamic performance of the isolator is evaluated in simulation. Experimental results indicate that both the stiffness and damping capability of the developed MR isolator can be controlled by an external magnetic field.

关键词： magnetorheological (MR) fluid     stiffness     damping     mathematical model     dynamic performance     parameter identification    

HTML PDF 收藏

Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 281-287 doi: 10.1007/s11709-012-0167-5

摘要： A new artificial boundary condition for time domain analysis of a structure-unlimited-foundation system was proposed. The boundary condition was based on the damping-solvent extraction method. The principle of the damping-solvent extraction method was described. An artificial boundary condition was then established by setting two spring-damper systems and one artificial damping limited region. A test example was developed to verify that the proposed boundary condition and model had high precision. Compared with the damping-solvent extraction method, this boundary condition is easier to be applied to finite element method (FEM)-based numerical calculations.

关键词： damping-solvent extraction method     structure-unlimited-foundation system     spring-damper system     artificial damping limited region     finite element method    

HTML PDF 收藏

Effects of green roof damping and configuration on structural seismic response

《结构与土木工程前沿（英文）》   页码 1133-1144 doi: 10.1007/s11709-023-0959-9

摘要： Sustainable structures are critical for addressing global climate change. Hence, their structural resilience or ability to recover from natural events must be considered comprehensively. Green roofs are a widely used sustainable feature that improve the environment while providing excellent occupant amenity. To expand their usage, their inherent damping and layout sensitivity to seismic performance are investigated in this study. The soil of a green roof can serve as a damper to dissipate the energy generated by earthquakes or other dynamic events. Results of preliminary analysis show that a green roof soil can increase localized damping by 2.5% under both dry and saturated conditions. Based on these findings, nonlinear time-history analyses are conducted on a three-story building in SAP2000 to monitor the structural behavior with and without a green roof. The increased damping in the green roof soil is beneficial to the structural performance, i.e., it reduces the building displacement and acceleration by 10% and 12%, respectively. Additionally, certain configurations are more effective and beneficial to the structural response than others, which suggests the possibility of design optimization. Based on the findings of this study, new methods of modeling and considering green roofs in structural design are established.

关键词： green infrastructure     green roof     structural resilience     seismic design    

HTML PDF 收藏

Fluid damping clearance in a control valve of injector

ZHANG Jianming, ZHANG Weigang, YANG Bing, WANG Yawei

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 439-441 doi: 10.1007/s11465-007-0075-x

摘要： A force model of a control valve of injector is set up, and the changes of the fluid damping clearance are investigated on the basis of the results of the computational fluid dynamics (CFD) and the experiments of control valve of injector. Results indicate that a damping clearance of 0.02–0.03 mm between the poppet and the valve guide is the most sufficient to dampen any excessive control valve poppet bouncing.

关键词： control     computational     bouncing     CFD     excessive control    

HTML PDF 收藏

A method of analysis for modal aero-damping of vibrating blade in incompressible flow

Jun XING, Lin LI,

《能源前沿（英文）》 2009年 第3卷 第4期   页码 465-471 doi: 10.1007/s11708-009-0037-6

摘要： By establishing a research model for aero-damping in a uniform incoming flow, the three-dimension analytical algorithm of the modal aero-damping based on the equivalent viscous damping principle was established. The algorithm, which is suited for low-speed flow, to compute aero-damping is based on classical lift line theory in aerodynamics, according to the analytical solution of unsteady aerodynamic force. According to the analytical equations, the modal aero-damping ratio for different nature frequencies of blades in various fluid field conditions can be solved, and the factors to affect the aero-damping can be determined.The first bend and the first torsion’s modal aero-damping ratios of a compressor blade are calculated by using the above algorithms. The results show that the aero-damping cannot be neglected comparing with the structure damping. It reflects the coupling degree between the flow field and the structure field, so the aero-damping is significant to compute the stress and life of blade.

关键词： compressor     different     three-dimension analytical     classical     low-speed    

HTML PDF 收藏

Dynamics of structural systems with various frequency-dependent damping models

Li LI,Yujin HU,Weiming DENG,Lei LÜ,Zhe DING

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 48-63 doi: 10.1007/s11465-015-0330-5

摘要：

The aim of this paper is to present the dynamic analyses of the system involving various damping models. The assumed frequency-dependent damping forces depend on the past history of motion via convolution integrals over some damping kernel functions. By choosing suitable damping kernel functions of frequency-dependent damping model, it may be derived from the familiar viscoelastic materials. A brief review of literature on the choice of available damping models is presented. Both the mode superposition method and Fourier transform method are developed for calculating the dynamic response of the structural systems with various damping models. It is shown that in the case of non-deficient systems with various damping models, the modal analysis with repeated eigenvalues are very similar to the traditional modal analysis used in undamped or viscously damped systems. Also, based on the pseudo-force approach, we transform the original equations of motion with nonzero initial conditions into an equivalent one with zero initial conditions and therefore present a Fourier transform method for the dynamics of structural systems with various damping models. Finally, some case studies are used to show the application and effectiveness of the derived formulas.

关键词： damping     viscoelasticity     dynamic analysis     mode superposition method     Fourier transform method    

HTML PDF 收藏

Inverse kinematics analysis and numerical control experiment for PRS-XY style hybrid machining tool

JIA Dongyong, ZHANG Jianmin, SUN Hongchang, NIU Zhigang

《机械工程前沿（英文）》 2007年 第2卷 第2期   页码 235-238 doi: 10.1007/s11465-007-0041-7

摘要： This paper analyzed the inverse kinematics for the new Parallel rotate slider- axes (PRS-) style hybrid machining tool and educed the five axes linkage inverse kinematics transform formula on the basis of the coordinates of the and virtual axes. The program for the PRS-XY style hybrid machining tool in accordance with the program manner for the common numerical control (NC) machine tool was made. The results of the experiments prove that the inverse kinematics transform formula is correct.

关键词： numerical     accordance     transform formula     virtual     slider-    

HTML PDF 收藏

Development of a seismic design method based on response spectra for building structures

ZHOU Xiyuan, YU Ruifang

《结构与土木工程前沿（英文）》 2007年 第1卷 第2期   页码 129-141 doi: 10.1007/s11709-007-0014-2

摘要： The assumption and problem of the mode-superposition response spectrum method in seismic design code is discussed based on a brief review of the development of the seismic design method for building structures. The scope of application for the classical damping theory is analyzed and the necessity of the research on mode-superposition method for non-classical damping is presented. The progresses on the mode superposition response spectrum theory are discussed. This includes: 1) the complex mode superposition method (in real form) for the non-classically damped linear system and the general calculation formula for the application of code; 2) the complex complete quadratic combination (CCQC) method for the non-classically damped linear system, which is based on the same assumptions as in deducing the complete quadratic combination (CQC) method which is popularly used in seismic design codes of many countries; 3) the complex complete quadratic combination with three components (CCQC3) method, which is a generalization of the CCQC method to the case of multi-components and multiple-support seismic excitations and deducing corresponding method; 4) the approach for calculation of seismic response of the non-classically damped system with overcritical damping and the calculation method of seismic response for the linear system with multiple eigenvalues; 5) the time-dependent CCQC (t) algorithm considering nonstationary earthquake ground motion; 6) an applied and effective method to solve the low order complex vector basis for the large linear non-classically damped system, which can be expediently used in practice to avoid the unknown errors coming from the forced uncoupling method; 7) bringing forward the concept of partial quadratic combination in order to reduce the calculation amount of CQC and CCQC methods, and studying the primary estimation-criterion. The reasonability and applicable scope of these methods are also briefly discussed in this paper.

关键词： generalization     classical damping     mode-superposition response     calculation formula     damping theory    

HTML PDF 收藏

标题 作者 时间 类型 操作

Joint slip investigation based on finite element modelling verified by experimental results on wind turbine lattice towers

Saleh YAGHOOBI, Ahmad SHOOSHTARI

期刊论文

Novel hierarchical yolk-shell

Xiqing Luo, Miaomiao Jiang, Kun Shi, Zhangxian Chen, Zeheng Yang, Weixin Zhang

期刊论文

Anti-β2GPI/β2GPI complexes induce platelet activation and promote thrombosis via p38MAPK: a pathway to targeted therapies

Wenjing Zhang, Caijun Zha, Xiumin Lu, Ruichun Jia, Fei Gao, Qi Sun, Meili Jin, Yanhong Liu

期刊论文

Minimal residual disease-directed immunotherapy for high-risk myelodysplastic syndrome after allogeneic hematopoietic stem cell transplantation

Xiaodong Mo, Xiaohui Zhang, Lanping Xu, Yu Wang, Chenhua Yan, Huan Chen, Yuhong Chen, Wei Han, Fengrong Wang, Jingzhi Wang, Kaiyan Liu, Xiaojun Huang

期刊论文

Controlled synthesis of uniform silver nanowires with high aspect ratios in aqueous solutions of gemini

XU Jian, LIU Weijun, LIU Honglai, HU Ying

期刊论文

Development of rocking constraint device with vertical damping capacity for three-dimensional base-isolated

期刊论文

Approximation of structural damping and input excitation force

Mohammad SALAVATI

期刊论文

Variable stiffness and damping magnetorheological isolator

Yang ZHOU, Xingyu WANG, Xianzhou ZHANG, Weihua LI

期刊论文

Study of an artificial boundary condition based on the damping-solvent extraction method

Qiang XU, Jianyun CHEN, Jing LI, Mingming WANG

期刊论文

Effects of green roof damping and configuration on structural seismic response

期刊论文

Fluid damping clearance in a control valve of injector

ZHANG Jianming, ZHANG Weigang, YANG Bing, WANG Yawei

期刊论文

A method of analysis for modal aero-damping of vibrating blade in incompressible flow

Jun XING, Lin LI,

期刊论文

Dynamics of structural systems with various frequency-dependent damping models

Li LI,Yujin HU,Weiming DENG,Lei LÜ,Zhe DING

期刊论文

Inverse kinematics analysis and numerical control experiment for PRS-XY style hybrid machining tool

JIA Dongyong, ZHANG Jianmin, SUN Hongchang, NIU Zhigang

期刊论文

Development of a seismic design method based on response spectra for building structures

ZHOU Xiyuan, YU Ruifang

期刊论文