检索结果-南通市图书馆

Nonlinear Dynamic Modeling for a Diesel Engine Propeller Shafting Used in Large Marines

Chinese Journal of Mechanical Engineering 2014年第5期27卷 937-948页

作者： ZHANG Qinglei DUAN Jianguo ZHANG Suohuai FU Yumin School of Mechanical Engineering University of Shanghai for Science and Technology Central Academe shanghai Electric Group Co. Ltd School of Mechanical and Automation Engineering shanghai institute of Technology

Longitudinal vibration,torsional vibration and their coupled vibration are the main vibration modes of the crankshaft-sliding bearing ***,these vibrations of the propeller-crankshaft-sliding bearing system generated by the fluid exciting force on the propeller are much more ***,the torsional and longitudinal vibrations have been studied separately while the research on their coupled vibration is few,and the influence of the propeller structure to dynamic characteristics of a crankshaft has not been studied *** order to describe the dynamic properties of a crankshaft accurately,a nonlinear dynamic model is proposed taking the effect of torsional-longitudinal coupling and the variable inertia of propeller,connecting rod and piston into *** simulation cases are carried out to calculate the response data of the system in time and frequency domains under the working speed and over-speed,*** of vibration analysis of the propeller and crankshaft system coupled in torsional and longitudinal direction indicate that the system dynamic behaviors are relatively complicated especially in the components of the frequency *** example,the 4 times of an exciting frequency acting on the propeller by fluid appears at 130 r/min,while not yield at 105 r/*** the possible abnormal vibration at over-speed just needs to be *** when designing the propeller shafting used in marine diesel engines,strength calculation and vibration analysis based only on linear model may cause great errors and the proposed research provides some references to design diesel engine propeller shafting used in large marines.

关键词： nonlinear dynamics propeller shafting marine engine numerical simulation

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

Numerical study of a supercritical airfoil/wing with variable-camber technology

引用

Chinese Journal of Aeronautics 2020年第7期33卷 1850-1866页

作者： Wei NIU Yufei ZHANG Haixin CHEN Miao ZHANG School of Aerospace Engineering Tsinghua UniversityBeijing 100084China shanghai Aircraft Design and Research institute Shanghai 201210China

Variable-camber technology is considered an effective way to adaptively improve the aerodynamic performance of aircraft under various flight *** paper studies the aerodynamic characteristics of the trailing-edge variable-camber technology by means of Computational Fluid Dynamics(CFD)and a drag decomposition ***-edge variable-camber technology can be simply realized by the continuous deflection of the flaps and ailerons of a wing.A supercritical airfoil is used to study the two-dimensional effect of variable-camber technology,and a wide-body airplane model is used to validate the three-dimensional improvement in the wing’s airfoil made by variable-camber *** optimization strategy for airfoil that incorporates variable-camber technology is *** optimization results demonstrate that the proposed method can obtain better results than the traditional segregated shape optimization.

关键词： Aerodynamic optimization CST method Drag decomposition Supercritical airfoil/wing Variable-camber technology

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

The storage and its stability of space charge in poly(ethylene naphthalene-2,6-dicarboxylate)

引用

Science China(Technological Sciences) 2006年第5期49卷 621-628页

作者： QIU Xunlin XIA Zhongfu WANG Feipeng Pohl institute of Solid-State Physics Tongji University Shanghai 200092 China Pohl Institute of Solid-State Physics Tongji University Shanghai 200092 China Pohl Institute of Solid-State Physics Tongji University Shanghai 200092 China

Poly(ethylene naphthalene-2,6-dicarboxylate) (PEN) is an aromatic polyester with molecular structure similar to that of poly(ethylene terephthalate)(PET). In this paper, the space charge storage ability and its stability in corona charged PEN were studied by measurement of surface potential decay under different storage conditions including dif- ferent temperatures and relative humidities, and analysis of open circuit thermally stimu- lated discharge (TSD) current spectra and charge TSD curves. The comparison between the charge stability of PEN and PET was carried out. The results point out that the charge stability of PEN is markedly better than that of PET under different environmental condi- tions. By means of isothermal depolarization program, the space charge lifetimes (effec- tive time constant) τ at room temperature of positively and negatively charged PEN are estimated to be 90 y. The results offer theoretical and technical support for the use of PEN as the chip of high quality electret condenser microphone due to its excellent dielectric, mechanical and thermal properties.

关键词： poly(ethylene naphthalene-2, 6-dicarboxylate), electret, charge stability, effective time constant.

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

Reversible Resistance Switching Effect in Amorphous Ge1Sb4Te7 Thin Films without Phase Transformation

引用

Chinese Physics Letters 2009年第2期26卷 123-125页

作者：孙华军侯立松吴谊群唐晓东 shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 Laboratory of Polar Materials and Devices East China Normal University Shanghai 200241

We demonstrate a reversible resistance switching effect that does not rely on amorphous-crystalline phase transformation in a nanoscale capacitor-like cell using Ge1Sb4Te7 films as the working material. The polarity and amplitude of the applied electric voltage switches the cell resistance between low- and high-resistance states, as revealed in the current-voltage characteristics of the film by conductive atomic force microscopy （CAFM）. This reversible SET/RESET switching effect is induced by voltage pulses and their polarity. The change of electrical resistance due to the switching effect is approximately two orders of magnitude.

关键词： No English Keywords

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

Understanding Modulus Variation of the Active Layers of Silicon Composite Electrodes

引用

Acta Mechanica Solida Sinica 2022年第6期35卷 987-995页

作者： Bowen Sun Yanfei Zhao Yicheng Song Junqian Zhang Bo Lu Department of Mechanics Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200444China shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai200444China Department of Civil Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai200444China Zhejiang Laboratory Hangzhou311100China

The variation of the effective modulus of silicon composite electrodes,which is a fundamental feature to analyze the coupled mechanical–electrochemical behavior of Si-based electrodes in high-capacity lithium-ion batteries,remains qualitatively *** clarify the contradictory experimental results,numerical modeling of a representative volume element with silicon particles,carbon-binder domains(CBDs),and pores has been performed for the lithiation *** key parameters for modulus variation were identified and evaluated.A mesostructure change is proposed to be a crucial mechanism that affects the modulus variation,and silicon softening is another key *** softening and the decreasing CBD volume fraction collectively result in a decrease in the effective modulus of the composite,whereas an increase in the silicon volume fraction along with a decrease in porosity has the opposite *** findings of this work provide an in-depth and fundamental understanding of the mechanical properties of silicon composite electrodes.

关键词： Modulus variation Silicon composite electrode Active layer Mesostructure change Silicon softening

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

THE STUDY OF QUASI WAVELETS BASED NUMERICAL METHOD APPLIED TO BURGERS' EQUATIONS

引用

Applied Mathematics and Mechanics(English Edition) 2000年第10期21卷 1099-1110页

作者：万德成韦国伟 shanghai institute of Applied Mathematics and Mechanics Shanghai University Shanghai P R China Department of Computational Science National University of Singapore Singapore

A quasi_wavelet based numerical method was introduced for solving the evolution of the solutions of nonlinear partial differential Burgers' equations. The quasi wavelet based numerical method was used to discrete the spatial deriatives, while the fourth_order Runge_Kutta method was adopted to deal with the temporal discretization. The calculations were conducted at a variety of Reynolds numbers ranging from 10 to unlimited large. The comparisons of present results with analytical solutions show that the quasi wavelet based numerical method has distinctive local property, and is efficient and robust for numerically solving Burgers' equations.

关键词： quasi_wavelets Runge_Kutta method Burgers' equations

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

Birefringent plate design for broadband spectral shaping in a Ti:sapphire regenerative amplifier

引用

Chinese Optics Letters 2007年第8期5卷 493-496页

作者：陆效明李闯冷雨欣王乘张春梅梁晓燕李儒新徐至展 shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences

A method to design a birefringent plate （BP） for broadening spectrum in a regenerative amplifier is presented. Using this method, we design a quartz BP with thickness of 761μm inserted into a Ti：sapphire regenerative amplifier. The gain narrowing effect is reduced efficiently, and the experimental results agree with the calculation well. The bandwidth is broadened from 28 to 62 nm using the designed quartz BP and the pulses are compressed to ～23 fs.

关键词： Bandwidth Birefringence Calculations

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

Boron Isotope Fractionation During Prolonged Ion Bombardment

引用

Chinese Physics Letters 1991年第6期8卷 325-328页

作者： ZHENG Liping LI Risheng LI Mingyao CHENG Yulin shanghai institute of Nuclear&search Academia SinicaShanghai 201800 institute of Metal&search Academia SinicaShenyang 110015

Dynamic Monte Carlo simulation is used to explore the B isotope sputtering during 1 keV Kr ion *** is found that at both zero and high fluences the light isotope is preferentially ejected in the near-normal direction;meanwhile,there is a low fluence(1.4×10^(15) ions/cm^(2)),at which the isotope fractionation is independent of the emission angle in the nearly whole angular range.

关键词： irradiation angular isotope

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

Surface structure design in solid particles

引用

Chinese Science Bulletin 1995年第24期40卷 2085-2089页

作者：温树林 shanghai institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

The most important parameters in solid particles are their size and chemical compositions. However,the structure of the particles(such aS crystalline state),specially Surface structure,plays even a greater role in som... 详细信息

关键词： surface structure Ni high Tc superconductors.

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

Generating a reporter mouse line marking medium spiny neurons in the developing striatum driven by Arpp21 cis-regulatory elements

引用

Journal of Genetics and Genomics 2018年第12期45卷 673-676页

作者： Pan Chen Xiangbin Ruan Yongqiang Chen Shilong Chu Kunlun Mo Chao Wu Wei Liu Bin Yin Junjie Zhou Liang Li Lin Hou Jiangang Yuan Boqin Qiang Jiekai Chen Pengcheng Shu Xiaozhong Peng State Key Laboratory of Medical Molecular biology Department of Molecular Biology and Biochemistry Institute of Basic Medical Sciences Medical Primate Research Center Neuroscience CenterChinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College CAS Key Laboratory of Regenerative biology South China Institute for Stem Cell Biology and Regenerative Medicine Guangzhou Institutes of Biomedicine and Health Chinese Academy of Sciences Department of Anatomy and Histology institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College institute of Medical biology Chinese Academy of Medical Sciences Chinese Academy of Medical Science and Peking Union Medical College

The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, 2008). Most cells in the striatum are GABAergic, including a large population (90%-95%) of medium spiny neurons (MSNs) and a small population of interneurons.

关键词： BAC Generating a reporter mouse line marking medium spiny neurons in the developing striatum driven by Arpp21 cis-regulatory elements cis

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：