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THE ESTIMATE AND measurement OF TRANSVERSE WAVE INTENSITY

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Acta Mechanica Solida Sinica 1997年第3期10卷 235-245页

作者： Ming Ruisen, Department of Architecture, zhejiang university, hangzhou 31002., china zhejiang UNIV DEPT ARCHITECTUREHANGZHOU 310027PEOPLES R CHINA

Transverse waves are a type of structural waves and should be considered in the analysis of high frequency vibration because the energy carried by transverse waves increases with the increase of frequency and becomes important at high frequencies. This paper studies the estimate theory and measuring technique of the transverse wave intensity in two-dimensional homogeneous structures. In general, the intensity vector is the sum of the effective intensity vector and the intensity variation vector. Each axial intensity component is proportional to two imaginary parts of cross spectral densities and its estimate is complicated. For the special case where transverse waves propagate in one direction, the intensity variation is zero and the estimate of the intensity is simplified. The intensity technique is formed based on the finite difference principle. Transverse wave intensity can be measured using a pair of two-transducer arrays lying in the orthogonal direction for the general case or a two-transducer array lying in the propagating direction for the special case. In order to assess the measurement accuracy of transverse wave intensify, the coupling loss factors from bending to transverse waves in building structures were measured using the intensity technique and compared with the results predicted and measured using the conventional method. It is shown that the agreement between the results measured using the intensity technique and that by the conventional method is good.

关键词： transverse wave intensity estimate theory measurement accuracy

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, zhejiang 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

Preparation and Conductivity of Triheteropoly Tungstozincoaluminic Acid

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Rare Metals 2001年第4期20卷 221-223页

作者： Qingyin Wu Department of Chemistry, zhejiang university, hangzhou 31002., china zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

The ternary undecatungstozincoaluminic heteropoly acid H-7[Al(H2O)ZnW11O39](.)12H(2)O was prepared by the ion exchanging-cooling method. The optimal proportion of solutions of the component elements and the pH of the synthesis reaction were given. The product was characterized by chemical analysis, potentiometric titration, IR, UV, XRD and TG-DTA. AC impedance measurement results show that its proton conductivity is 1.37x10(-4) S/cm at 18 degreesC.

关键词： heteropoly acid tungstozincoaluminic acid protonic conductivity

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 31002.,china 2Research center for Terahertz Technology,zhejiang university,hangzhou 31002.,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

Is There any Hexazirconium Cluster in the Compounds [HP(t-Bu)_2Ph_3]_3[Zr_6Cl_(18)H_5] and Zr_6Cl_(14)(PPr_3)_4H_4?

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Chinese Chemical Letters 1997年第9期8卷 829-830页

作者： Wen LI ChunHua HU Pei Ju ZHENG(Research center of analysis and measurement, Fudan university, Shanghai 200433) FUDAN UNIV RES CTR ANAL & MEASUREMENTSHANGHAI 200433PEOPLES R CHINA

The [Zr6(μ2-Cl)12Cl6H4]3- ion with C4v Symmetry in the title compounds has been calculated by DV-Xα program. The calculated results show that ther is almost no available covalence bonding between zirconium atoms and significant Zr 4d AO compositions in the MOs. but there are much stronger Zr-Cl(bridging) bonding. All analysis results suggest that these compounds would be the cluster with Zr6Cl12 cage linked by Zr-Cl bridging bonding plus six Cl teminal ligands rather than the hexazirconium cluster in view of the chemical bonding.

关键词： and Zr6Cl PPr3 Is There any Hexazirconium Cluster in the Compounds t-Bu H5 Zr6Cl HP

Pollen morphology of Rhododendron subgen. Tsutsusi and its systematic implications

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Journal of Systematics and Evolution 2009年第2期47卷 123-138页

作者： 1,2Yue-Jiao ZHANG 1Xiao-Feng JIN 3Bing-Yang DING 4Jing-Ping ZHU 1(School of Life & Environment Sciences,hangzhou Normal university,hangzhou 310036,china) 2(College of Life Sciences,zhejiang university,hangzhou 310012,china) 3(School of Life & Environment Sciences,Wenzhou university,Wenzhou 325027,china) 4.center of analysis & measurement,zhejiang university,hangzhou 31002.,china) ( center of analysis & measurement Zhejiang University Hangzhou 310028 China )

Eighty-four pollen samples were obtained for 80 taxa,of which,13 species and one variety are from *** Sweet,58 species and two varieties from *** Sweet,and six species from ***(***) Pojarkova,*** morphology of all samples was observed using LM and *** grains are revealed to be spheroidal and tetrahedral with tricolporate *** sizes of ***(Sweet) Pojarkova range from 37.67 μm to 61.06 μm,and the exine sculptures are more or less compactly *** sizes are significantly different between *** and *** of *** tashiroi *** *** Sleumer shows a close affinity to *** size and exine are consistent with general morphology in differentiating species in *** huadingense *** & ***,once placed as a member of ***,should be considered as a species in ***.

关键词： Ericaceae Rhododendron subgen.Tsutsusi pollen morphology tetrahedral tetrads systematic implication

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 31002.,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 31002.,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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Synthesis of Nanometer-sized Mesoporous Oxide Spheres

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Chemical Research in Chinese Universities 2001年第2期17卷 143-147页

作者： LUO Qian, LI Li, XUE Zhi-yuan and ZHAO Dong-yuan (Department of Chemistry analysis and measurement center, Fudan university, Shanghai 200433, P. R. china) Fudan Univ Dept Chem Shanghai 200433 Peoples R China Fudan Univ Ctr Anal & Measurement Shanghai 200433 Peoples R China

A few hundreds nanometer-sized mesoporous silica and alumina spheres were synthesized in organic solvents. The impacts of ammonia, N, N-dimethylformamide (DMF) and stirring speed were also investigated.

关键词： Nanometer-sized Mesoporous Sphere Silica Alumina

A NOTE ON UNCERTAINTY PRINCIPLE

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analysis in Theory and Applications 1995年第1期11卷 6-9页

作者： Quande Chen and Qiyu Sun(hangzhou university, china and zhejiang university, china) 1. Department of Mathematics Hangzhou University 310028 Hangzhou Zhejiang PRC2. Center for Mathematical Sciences Zhejiang University 310027 Hangzhou Zhejiang PRC

weighted form of uncertainty principle is proved.

关键词： A NOTE ON UNCERTAINTY PRINCIPLE II real