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Quasi-static analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅱ:Results and Discussion

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 81-87页

作者： CHEN Wenhua1,2.MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2.1 Institute of Mechanical Design,zhejiang University,hangzhou {2.,china 2.Institute of Mechanical Design and Manufacturing,zhejiang Sci-Tech University,hangzhou 310018,china 3 State Testing Laboratory of hangzhou Bearing Test & Research center,hangzhou {2.,china 1. Institute of Mechanical Design Zhejiang University Hangzhou 310027 China 2. Institute of Mechanical Design and Manufacturing Zhejiang Sci-Tech University Hangzhou 310018 China 3. State Testing Laboratory of hangzhou Bearing Test & Research center Hangzhou 310022 China

Ball bearings are widely employed mechanical components characterized by high precision and quality,and usually play important roles in various rotary machines and *** advanced applications require a deep understanding of their various kinematic and tribological characteristics that are essential to predict the fatigue endurance,relieve the vibration and minimize the power dissipation of ball bearings in particular *** angular contact ball bearing under a specified operating condition is simulated with the quasi-static/creepage analytical model proposed in the preceding *** results demonstrate that the ball bearing is a statically determinate *** the balls spin on both inner and outer races means the ball is controlled by neither the inner nor the outer *** friction between the ball and raceway renders the inner and outer contact angles *** larger the coefficient of friction is,the larger the angle *** tangential traction perpendicular to the rolling direction due to the spin induces a gyro-like rotation of the ball with respect to the raceway even if no inertial effects are *** tangential elastic compliance of contacting surfaces gives rise to locked areas within the contact patch and transforms the sliding lines from circles into *** differential slip due to the close conformity of the ball and raceway makes the sliding and traction distributions asymmetric,which will influence the location of the spinning center of the ball with respect to the *** quasi-static/creepage model can be used to reveal the operating behaviors of ball bearings running under steady conditions and to optimize the design of ball bearings for specific applications.

关键词： ball bearing quasi-static creepage differential slip tangential elastic compliance

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Surface electromagnetic modes contribution to the anomalous terahertz transmission through double-layered metal hole array

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Science china(Information Sciences) 2012年第1期55卷 90-97页

作者： RAO Lei1&YANG DongXiao1,2.1Department of Information Science and Electronic Engineering,zhejiang University,hangzhou {2.,china 2.esearch center for Terahertz Technology,zhejiang University,hangzhou {2.,china 1. Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China2. Research Center for Terahertz Technology Zhejiang University Hangzhou 310027 China

Terahertz transmission spectra through both single-layered and double-layered sub-wavelength metal hole arrays were calculated using rigorous mode-matching *** dispersion relations of the single-layered and double-layered metal hole arrays were obtained by FDTD *** are three anomalous peaks in the spectrum of the double-layered metal hole array,which arise from the three surface electromagnetic modes appearing in the dispersion *** comparing the transmission spectra and the dispersion relations of the single-layered and double-layered metal hole arrays,it was found that the two surface electromagnetic modes at higher frequencies are introduced by the single-layered metal hole array,while the one at lower frequencies is introduced by the double-layered metal hole *** validity of the analysis was qualitatively verified by the experimental *** structure can be finely designed for potential applications,such as wideband filtering.

关键词： surface electromagnetic modes double-layered metal hole array terahertz

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2. WANG Xiaofeng1, CAO Maosheng3 and LIANG Ji1(1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, china 2. center for {2. and measurement, Harbin Institute of Technology, Harbin 150001, china 3. School of Material Science and Engineering, Tsinghua University, Beijing 100084, china) Department of Mechanical Engineering Tsinghua University Beijing 100084 China center for analysis and {2. Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Deformation in the Three Gorges Reservoir after the first impoundment determined by GPS measurements

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Progress in Natural Science:Materials International 2005年第6期15卷 515-522页

作者： DU Ruilin 1,2., QIAO Xuejun 1,2.*, WANG Qi 1,2., XING Canfei 1,2.and YOU Xinzhao 1,3 (1. Institute of Seismology, CEA, Wuhan 430071, china 2. Laboratory of Crustal Movement and Earth Observation, Wuhan 430071, china 3. {2. for analysis and Prediction, CEA, Beijing 100036, china) Institute of Seismology CEA Wuhan 430071 China Laboratory of Crustal Movement and Earth Observation Wuhan 430071 China center for analysis and Prediction CEA Beijing 100036 China

A 6-year long GPS observation (1998—2.03) indicates that crustal deformation in the Three Gorges area is less active at a marginally measurable rate of 0—5 mm/a relative to stable South china block. However, the impounding water in June 2.03 has induced transient displacement at the Three Gorges dam and the emerging reservoir. GPS measurements after the first stage of water filling of the reservoir demonstrate that vertical subsidence close by Yangtze River is about 10—40 mm, and the horizontal displacement is less than 5—10 mm. The maximum subsidence induced by the impoundment is located in the segment of the reservoir from Maoping to Xiangxi. The water loading-induced deformation diminishes rapidly with the distance from banks of the reservoir. The overall pattern of transient deformation is consistent with the simulation result of Farrell, and is attributed to the elastic response of upper lithosphere crust to overlying water reservoir.

关键词： Three Gorges GPS impoundment deformation.

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, china 2. Graduate School of Chinese Academy of Sciences, Beijing 100049, china 3. Department of Physics, Zhoukou Normal University, Zhoukou 466100, china 4. Research Imaging center, University of Texas Health Science center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering center, Institute of Automation, Chinese Academy of Sciences, Beijing 100049, china 6. Department of Physics, zhejiang University, hangzhou 31002., china) [a]Key Laboratory of Nuclear analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]Department of Physics Zhoukou Normal University Zhoukou China [d]Research Imaging center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of Physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

PREPARATION AND MICROSTRUCTURE OF NANO-SIZED Cu PARTICLES BY MECHANOCHEMICAL REACTION

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中国有色金属学会会刊：英文版 1998年第4期8卷 79-81页

作者： Wu Nianqiang, Su Lizhi, Yuan Mingyong , Liu Yuyong, Wu Jinming and Li Zhizhang Department of Materials Science and Engineering center of Measure and analysis, {2. University, hangzhou 31002., P. R. china center of Measure and analysis Zhejiang University Hangzhou 310027 China Department of Materials Science and Engineering

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关键词： nanostructured material copper mechanical alloying nanoparticle

Heart failure in china:epidemiology and current management

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Journal of Geriatric Cardiology 2024年第6期21卷 631-641页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

The Annual Report on Cardiovascular Health and Diseases in china(2.2.)intricate landscape of cardiovascularhealth in *** connection with the previous section,this sixth section of the report offers a comprehensive analysis of heart failure(HF)in *** is one of the most important cardiovascular disease in the 2.st *** mortality is equivalent to that of *** is an important public health problem that seriously affects the health of Chinese *** recent years,with the deepeningof understanding,the change of treatment principles,the innovation of treatment methods and the update of treatment guidelines,the in-hospital mortality of HF patients has declined,and the long-term prognosis is also ***,there are stilldifferences in the management level of HF among different hospitals in *** to improve the standardized diagnosis andtreatment level of HF in china remains an important challenge.

关键词： epidemiology diagnosis treatment

The adsorption isotherms, IR and ^(2.)Si MAS NMR spectra of modified MCM-41 molecular sieves

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Chinese Science Bulletin 1997年第10期42卷 828-832页

作者： LONG Yingcai, DONG Weiyang, XU Taiming, GAO Xiaoqin, XIE Guangen and SUN Yaojun1. Department of Chemistry, Fudan University, Shanghai 2.0433, china 2. Centre of analysis and {2., Fudan University, Shanghai 2.0433, china Department of Chemistry Fudan University Shanghai China Centre of analysis and measurement Fudan University Shanghai China

RECENTLY a new family of mesoporous molecular sieves,M41S,was reported by researchers atMobil R&D *** a member of the family,MCM-41,which exhibits a hexagonalarray of uniform channel mesopores,has been *** channel size can be variedfrom approximately 1.5 nm to greater than 10 nm by choosing different surfactants,auxiliarychemicals(1,3,5-trimethylbenzene)in the reactant,and by changing the reaction *** wall thickness of this kind of molecular sieve is in the range of 0.3 to 1.3 nm esti-

关键词： MCM-41 surface modification adsorption isotherm IR 2.Si MAS NMR.

Synthesis of Novel SnO_2.Quantum Cubes and Their Selfassembly

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Journal of Wuhan University of Technology(Materials Science) 2011年第2期26卷 270-273页

作者：俞中平王智宇 State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang University

Nano-structured cubic SnO2.crystalines were successfully synthesized through solvothermal *** obtained products were characterized by X-ray diffraction （XRD）,transmission electron microscopy （TEM） and high resolution TEM （HRTEM）.The study showed that,the SnO2.particles were rutile structured and almost uniformly cube shaped crystals in quantum size （3-8 nm）.Self-assembly behavior of the cubic SnO2.quantum dots was also *** synthesis process can be defined as an nonhydrolysis （NH） hydroxylation reaction provided by the amide elimination of carboxylated *** formation of cubic morphology of SnO2.can be ascribed to the mild reaction featured by high nucleation rate and low growth rate,surface energy difference of the crystallographic facets of SnO2.and the passivation effect of the starting material-dodecylamine which drastically reduced the dipole *** selfassembly of the cubic SnO2.quantum dots was driven by van der Waals force and capillary force.

关键词： nanocube quantum dot crystal growth tin oxide