检索结果-南通市图书馆

Effect of cavity defect on the triaxial mechanical properties of high-performance concrete

Frontiers of Structural and Civil Engineering 2022年第5期16卷 600-614页

作者： yanbin zhang Zhe WANG Mingyu FENG School of Civil Engineering Beijing Jiaotong UniversityBeijing100044China

The stress concentration of pipe structure or cavity defect has a great effect on the mechanical properties of the high-performance concrete(HPC)members in deep underground ***,the behaviour of HPC with cavities under triaxial compression is not understood,especially when pressurized liquid flows into the fractures from the *** study aims to investigate the effect of the cavity and the confining pressure on the failure mechanisms,strengths,and deformation properties of HPC with a new experimental *** this experiment,the pressurized liquid can only contact the surface of the sample in the cavity,while the other surfaces are isolated from the pressurized *** further explore the effect of the cavity,the same experiments are also conducted on sealed and unsealed intact samples without a *** failure modes and stress-strain curves of all types of the samples are *** various confining pressures,all the samples with a cavity suffer shear failure,and there are always secondary tensile fractures initiating from the cavity ***,it can be determined from the failure modes and the stress-strain curves that the shear fractures result from the sidewall *** on the different effects of the cavity on the lateral deformations in different directions,the initiation of the sidewall fracture is well *** experimental results show that both the increase of the confining pressure and the decrease of the cavity size are conducive to the initiation of sidewall ***,the cavity weakens the strength of the sample,and this study gives a modified Power-law criterion in which the cavity size is added as an impact factor to predict the strength of the sample.

关键词： high-performance concrete cavity conventional triaxial compression pressurized liquid modified power-law criterion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamic Modeling and Experimental Verification of an RPR Type Compliant Paralle Mechanism with Low Orders

引用

Chinese Journal of Mechanical Engineering 2024年第3期37卷 83-94页

作者： Shuang zhang Jingfang Liu Huafeng Ding yanbin zhang School of Mechatronics Engineering Henan University of Science and TechnologyLuoyangHenanChina Faculty of Materials and Manufacturing College of Mechanical Engineering and Applied Electronics TechnologyBeijing University of TechnologyBeijingChina Key laboratory of advanced manufacturing technology Beijing University of TechnologyBeijingChina School of Mechanical Engineering and Electronic Information China University of Geosciences(Wuhan)WuhanChina Center of Machinery Equipment Advanced Manufacturing of Henan Province LuoyangChina

Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture *** modeling with low orders of a 2R1T compliant parallel mechanism is studied in the *** mechanism with two out-of-plane rotational and one lifting degrees of freedom(DoFs)plays an important role in posture *** on elastic beam theory,the stiffness matrix and mass matrix of the beam element are established where the moment of inertia is *** improve solving efficiency,a dynamic model with low orders of the mechanism is established based on a modified modal synthesis ***,each branch of the RPR type mechanism is divided into a ***,a set of hypothetical modes of each substructure is obtained based on the C-B ***,dynamic equation of the whole mechanism is established by the substructure assembly.A dynamic experiment is conducted to verify the dynamic characteristics of the compliant mechanism.

关键词： Compliant parallel mechanism Dynamic model Modal synthesis method Dynamic experiment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Specific grinding energy and surface roughness of nanoparticle jet minimum quantity lubrication in grinding

引用

Chinese Journal of Aeronautics 2015年第2期28卷 570-581页

作者： zhang Dongkun Li Changhe Jia Dongzhou zhang yanbin zhang Xiaowei School of Mechanical Engineering Qingdao Technological University

Nanoparticles with the anti-wear and friction reducing features were applied as cooling lubricant in the grinding fluid. Dry grinding, flood grinding, minimal quantity of lubrication （MQL）, and nanoparticle jet MQL were used in the grinding experiments. The specific grinding energy of dry grinding, flood grinding and MQL were 84, 29.8, 45.5 J/mm3, respectively. The speci- fic grinding energy significantly decreased to 32.7 J/mm3 in nanoparticle MQL. Compared with dry grinding, the surface roughness values of flood grinding, MQL, and nanoparticle jet MQL were sig- nificantly reduced with the surface topography profile values reduced by 11%, 2.5%, and 10%, respectively, and the ten point height of microcosmic unflatness values reduced by 1.5%, 0.5%, and 1.3%, respectively. These results verified the satisfactory lubrication effects of nanoparticle MQL. MoS：, carbon nanotube （CNT）, and ZrO2 nanoparticles were also added in the grinding fluid of nanoparticle jet MQL to analyze their grinding surface lubrication effects. The specific grinding energy of MoS2 nanoparticle was only 32.7 J/mm3, which was 8.22% and 10.39% lower than those of the other two nanoparticles. Moreover, the surface roughness of workpiece was also smaller with MoS2 nanoparticle, which indicated its remarkable lubrication effects. Furthermore, the role of MoS2 particles in the grinding surface lubrication at different nanoparticle volume con- centrations was analyzed. MoS2 volume concentrations of 1%, 2%, and 3% were used. Experimental results revealed that the specific grinding energy and the workpiece surface roughness initially increased and then decreased as MoS2 nanoparticle volume concentration increased. Satisfactory grinding surface lubrication effects were obtained with 2% MoS2 nanoparticle volume concentration.

关键词： Grinding Minimal quantity of lubrica-tion (MQL) Nanoparticle Specific grinding energy Surface roughness

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced Heat Transfer Technology Based on Emission Reduction and Carbon Reduction in Cutting and Grinding

引用

Chinese Journal of Mechanical Engineering 2023年第4期36卷 1-3页

作者： Changhe Li yanbin zhang Shubham Sharma School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Department of Mechanical Engineering and Advanced Materials Science Regional Center for Extension and DevelopmentCouncil of Scientific and Industrial Research(CSIR)-Central Leather Research Institute(CLRI)Jalandhar 144021India

Huge carbon emissions in machining process,which characterized by high energy consumption and usage of non-renewable resources,is becoming an obsession in the past *** the face of the international strategy of carbon peak,it is imperative to eliminate the usage of mineral cutting fluids and reduce energy consumption and carbon emissions by green cutting/grinding technologies,such as dry cutting,minimum quantity lubrication(MQL).

关键词： grinding lubrication eliminate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Superposition model for analyzing the dynamic ground subsidence in mining area of thick loose layer

引用

International Journal of Mining Science and Technology 2018年第4期28卷 656-661页

作者： Defeng Hou Dehai Li Guosheng Xu yanbin zhang College of Resources & Safety Engineering China University of Mining & Technology Institute of Energy Science and Engineering Henan Polytechnic Universit

The dynamic ground subsidence due to underground mining is a complicated time-dependent and rate- dependent process. Based. on the theory of rock rheology and probability integral method, this study developed the superposltlOn model for the prediction and analysis of the ground dynamic subsidence in mining area of thick !oose layer. The model consists of two parts （the prediction of overlying bedrock and the prediction of thick loose layer）. The overlying bedrock is regarded as visco-elastic beam, of which the dynamic subsidence is predicted by the Kelvin visco-elastic rheological model. The thick loose layer is regarded as random medium, and the ground dynamic subsidence, is predicted by the probability integral model. At last, the two prediction models are vertically stacked in the same coordinate system, and the bedrock dynamic subsidence is regarded as a variable mining thickness input into the prediction model of ground dynamic subsidence. The prediction results obtained were compared w^th actual movement and deformation data from Zhao I and Zhao II mine, central China. The agreement of the prediction results with the. field *** that the superposition model （SM） is more satisfactory and the formulae obtained are more effective than the classical single probability Integral model（SPIM）, and thus can be effectively used for predicting the ground dynamic subsidence in mining area of thick loose layer.

关键词： Thick loose layer Dynamic groundsubsidence Kelvin visco-elastic rheological model Random medium Single probability integral model Superposition model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

HOSVD-Based Subspace Algorithm for Multidimensional Frequency Estimation Without Pairing Parameters

引用

Chinese Journal of Electronics 2014年第4期23卷 729-734页

作者： WU Yuntao HUANG Longting CAO Hui zhang yanbin Key Laboratory of Intelligent Robot in Hubei Province Wuhan Institute of Technology Department of Electronic Engineering City University of Hong Kong School of Information and Communication Engineering Beijing University of Posts and Telecommunications

In this paper, a new method for multidimensional frequency estimation of multiple sinusoids that combines the HOSVD(Higher-order singular value decomposition) subspace and projection separation approaches is presented. Frequency parameters in the first dimension are obtained by using the signal subspace of the first dimension which is extracted by the HOSVD decomposition. Subsequently, a set of projection separation matrices is constructed to project the measure tensor and separate the components of the received tensor into single *** then, the signal subspace of each dimension of separated measure tensor are estimated by the HOSVD decomposition and the desired multidimensional frequency pairing are automatically obtained. Simulation results are included to demonstrate the advantage of the proposed method over two existing methods in terms of performance as well computational load.

关键词： Multidimensional frequency estimation Higher-order singular value decomposition Subspacebased method Projection separation appro

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Model for atomization droplet size and energy distribution ratio at the distal end of an electrostatic nozzle

引用

Frontiers of Mechanical Engineering 2024年第5期19卷 33-58页

作者： Dongzhou JIA Keke JIANG yanbin zhang Zhenlin LV Changhe LI College of Mechanical Engineering and Automation Liaoning University of TechnologyJinzhou 121001China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China

Electrostatic atomization minimum quantity lubrication(EMQL)employs the synergistic effect of multiple physical fields to atomize minute quantities of *** innovative methodology is distinguished by its capacity to ameliorate the atomization attributes of the lubricant substantially,which subsequently augments the migratory and infiltration proficiency of the droplets within the complex and demanding milieu of the cutting *** with the traditional minimum quantity lubrication(MQL),the EMQL process is further complicated by the multiphysical field *** presence of multiple physical fields not only increases the complexity of the forces acting on the liquid film but also induces changes in the physical properties of the lubricant itself,thus making the analysis of atomization characteristics and energy distribution particularly *** address this objective reality,the current study has conducted a meticulous measurement of the volume average diameter,size distribution span,and the percentage concentration of inhalable particles of the charged droplets at various intercept positions of the EMQL nozzle.A predictive model for the volume-averaged droplet size at the far end of the EMQL nozzle was established with the observed statistical value F of 825.2125,which indicates a high regression accuracy of the ***,based on the changes in the potential energy of surface tension,the loss of kinetic energy of gas,and the electric field work at different nozzle orifice positions in the EMQL system,an energy distribution ratio model for EMQL was *** energy distribution ratio coefficients under operating conditions of 0.1 MPa air pressure and 0 to 40 kV voltage on the 20 mm cross-section ranged from 3.094‰to 3.458‰,while all other operating conditions and cross-sections had energy distribution ratios below 2.06‰.This research is expected to act as a catalyst for the progression of EMQL by stimulating innovation in the sp

关键词： atomization performance EMQL energy distribution PIV observation sustainable manufacturing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

In situ simultaneous determination of trace elements,U-Pb and Lu-Hf isotopes in zircon and baddeleyite

引用

Chinese Science Bulletin 2008年第10期53卷 1565-1573页

作者： XIE LieWen zhang yanbin zhang HuiHuang SUN JingFeng WU FuYuan State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029China

This paper describes a combined method of simultaneously measuring U-Pb and Lu-Hf isotopes as well as trace elements in Phalaborwa baddeleyite and 91500, GJ-1, TEMORA-1 and SK10-2 zircons by means of Neptune MC-ICPMS and Agilent Q-ICPMS connected to a 193 nm excimer laser ablation system. Material ablated by laser was carried in different proportions into Q-ICPMS for U-Pb isotopic and trace elemental and MC-ICPMS for Lu-Hf isotopic compositions. Experiments indicate that different proportions of ablated material for the Q-ICPMS and MC-ICPMS (6:4, 5:5 and 4:6 respectively) do not show any bias for the zircon/baddeleyite U-Pb age, Lu-Hf isotope and trace elemental compositions within ana-lytical errors. Using 40―60 μm spot size, the obtained U-Pb ages of Phalaborwa baddeleyite, 91500, GJ-1, TEMORA and SK10-2 zircons are 2065±15 (2σ, n=20), 1063±6 (2σ, n=19), 613±6 (2σ, n=20), 416±5 (2σ, n=20) and 32.6±0.5 (2σ, n=20) Ma, respectively. The 176Hf/177Hf ratios are 0.281231±24 (2SD, n=20), 0.282310±35 (2SD, n=19), 0.282028±34 (2SD, n=20), 0.282687±34 (2SD, n=20) and 0.282752±53 (2SD, n=20), respectively. The obtained trace elemental compositions are identical to the reference values. Therefore, this kind of technique makes it possible to simultaneously obtain the U-Pb age, Lu-Hf iso-topes and trace elemental compositions of zircon and baddeleyite, which could be an important tool in solving problems in earth sciences.

关键词：镥-铪同位素锆石年代测量地球化学

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cis-regulatory change and expression divergence between duplicate genes formed by genome duplication of Arabidopsis thaliana

引用

Chinese Science Bulletin 2010年第22期55卷 2359-2365页

作者： CHEN KeNian zhang yanbin TANG Tian SHI SuHua State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China Department of Biotechnology Guangzhou Medical College Guangzhou 510182 China College of Computer Science Hangzhou Dianzi University Hangzhou 310018 China

As an index of functional divergence, expression divergence between duplicate gene copies has been observed and correlated with protein coding sequence divergence and bias in gene functional classes. However, the changes in the cis-regulatory region of the duplicate genes which is thought to have important role in expression divergence, has not been explored on the genome-wide scale. We analyzed functional genomics data for a large number of duplicated gene pairs formed by ancient polyploidy events in Arabidopsis thaliana. The divergence in cis-regulatory regions between two copies is positively correlated with the magnitude difference of expression. Moreover, we find that highly expressed duplicate gene pairs have a more diverged cis-regulatory region than weakly expressed gene pairs. We also show that the correlation between expression functional constraint and protein functional constraint is different in old and young duplicate pairs. Our results suggest that cis-regulatory sequence divergence contributes to the expression divergence of duplicate genes formed by genome-wide duplication. Cis-regulatory region diverges faster in highly expressed duplicate pairs. The diversify selection strengths that act on cis-regulatory region and protein coding region are negatively correlated in young duplicate pairs under expression constraint.

关键词：全基因组拟南芥独联体分歧复形监管基因表达差异蛋白质编码区

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Landslide Hazard and Risk Assessment on the Northern Slope of Mt. Changbai, China

引用

Acta Geologica Sinica(English Edition) 2008年第1期82卷 214-224页

作者： LIU Zhenghua zhang yanbin Yoshiharu ISHIKAWA Hiroyuki NAKAMURA Zhejiang Geological Environmental Monitoring Station Zhejiang 310007 China Zhejiang Land Consolidation and Rehabilitation Centre Zhejiang 310007 China Tokyo University of Agriculture and Technology Tokyo 183-8509 Japan

Landslide hazard and risk assessment on the northern slope of Mt. Changbai, a well-known tourist attraction near the North Korean-Chinese border, are assessed. This study is divided into two parts, namely, landslide hazard zonation and risk assessment. The 1992 Anbalagan and Singh method of landslide hazard zonation （LHZ） was modified and used in this area. In this way, an Associative Analysis Method was used in representative areas to get a measure for controlling factors （slope gradient, relative relief, vegetation, geology, discontinuity development, weak layer thickness and ground water）. For the membership degree of factor to slope failure, the middle range of limited values was used to calculate LHZ. Based on an estimation of the potential damage from slope failure, a reasonable risk assessment map was obtained using the relationship of potential damage and probable hazard to aid future planning and prediction and to avert loss of life.

关键词： Landslide Hazard Zonation (LHZ) controlling factor Associative Analysis Method membership degree risk assessment tourism China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：