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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2 1. College of Science, china Agricultural university, Beijing 100083, china 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering Science,{4., Beijing 100871, china 1. College of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

VOLTAMMETRIC BEHAVIORS OF ADRENALINE AND ITS Be(Ⅱ)COMPLEX

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Chinese Chemical Letters 1991年第9期2卷 731-734页

作者： Xian Zeng YE Jian Min HOU Song GAO Xiao Xia GAO department of Chemistry,peking university,Beijing 100871 De Min WANG department of Technical physics,peking university,Beijing 100871

The electrochemical oxidation behaviors of adrenaline(AD)and its Be(Ⅱ)complex have been studied by voltammetric method with a carbon paste working *** the bases of calculation of the atomic net electronic charges of AD molecule by INDO approximate method and results of comparative experiment with dopamine the possible coordination site of Be(Ⅱ)-AD complex is proposed.

关键词： VOLTAMMETRIC BEHAVIORS OF ADRENALINE AND ITS Be COMPLEX AD ITS

ON THE VALENCE STATE OF COPPER IN HIGH T_c SUPERCONDUCTOR YBa_2Cu_3O_x

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Journal of Rare Earths 1990年第1期8卷 26-30页

作者： Song Zengfu Wang Jiafu Lei Zimin Wu Jinguang Xu Guangxian(department of Chemistry,department of physics,peking {4.,Beijing 100871,P.R.china)

Various optical luminescence spectroscopic techniques were used to characterize the high T_c superconductor YBa_2Cu_3O_*** emission bands reveal that Cu^(3+) coexist with Cu^(2+) and Cu^+ in this material.

关键词： YBCO ON THE VALENCE STATE OF COPPER IN HIGH Tc SUPERCONDUCTOR YBa2Cu3Ox Cu

COLLISION OF WATER DROP ON WATER

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Acta Mechanica Sinica 1988年第4期4卷 297-304页

作者： Cai Yikun (department of physics,peking university,International Centre for Materials physics,Academia Sinica) 1. department of physics Peking University International Centre for Materials Physics Academia Sinica Beijing China

A series of experiments are performed to study the collision of a water drop with variousimpact velocities,ranged from 0 to 600 cm/s,onto a water *** kinds of phenomena have *** of them named"penetration"and"cleavage",were observed for low impact velocity(up to100 cm/s).Their common characteristics are that no obvious disturbances on the surface were observedduring the coUiding *** no splashing jets nor obvious crater were *** penetrationwe mean that a drop fallen into water becomes a ring,which penetrates the water smoothly with a velocityof several centimeters per *** the penetrating process no obvious change of its configurationwas *** falling height corresponding to penetration is proportional to volume of the *** periodicity of the falhng heights(corresponding to penetration)was *** named"cleavage"occurs when the impact velocity is other than that corresponding topenetration,then the drop cleaves into an"inverted cauliflower"after falling below the surface of *** does not *** diffusing and slowly expanding it vanishes in the vessel water several *** two kinds of phenomena,as we know,have not been reported *** the impact velocityapproaches or exceeds 100 cm/s,the third kind of phenomena,the splash,*** diameter anddepth of the crater occuring in the case of splash,together with the time for the crater to reach itsmaximum size,and the time for the rebounding column to begin to rise are given as functions of the fallingheight of the drop.

关键词： splash water drop penetration water surface impact

The refined theory of deep rectangular beams based on general solutions of elasticity

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2 1. College of Science, china Agricultural university, Beijing 100083, china 2. State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Engi- neering Science,{4., Beijing 100871, china College of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems department of Mechanics Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

Propagation of interplanetary shock excited ultra low frequency (ULF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

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Science china(Technological Sciences) 2010年第9期53卷 2528-2534页

作者： WANG ChengRui1,2,ZONG QiuGang1,3 & WANG YongFu1 1 Institute of Space physics and Applied Technology,peking university,Beijing 100871,{4. 2 Sate Key Laboratory of Space Weather,Chinese Academy of Sciences,Beijing 100190,{4. 3 Center for atmospheric Research,600 Suffolk Street,university of Massachusetts Lowell,MA 01854.USA 1. Institute of Space physics and Applied Technology Peking University Beijing 100871 China2. Sate Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Center for Atmospheric Research University of Massachusetts 600 Suffolk Street Lowell MA 01854 USA

The ultra low frequency (ULF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the ULF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the ULF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the ULF *** a comparison with recent observations,we found that: in the event during November 7,2004.that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the ULF waves and changed into geomagnetic *** result reveals that the ULF wave is in contact with the ground geomagnetic *** ULF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between CLUSTER multi-satellite observation and geomagnetic station observation is due to the ULF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (ULF) wave magnetic storm ionosphere IRI model interplanetary shock

Status of study on biological and toxicological effects of nanoscale materials

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Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy physics, Chi-nese Academy of Sciences, Beijing 10004., china 2. College of Chemistry and Molecular Engineering, peking university, Beijing 100871, china 3. department of Occupational and Environmental Health Sciences, School of Public Health, peking university, Beijing 100083, china 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 3. department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Intensified Hadley Circulation and Increasing Outgoing Long-wave Radiation

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Intensified Hadley Circulation and Increasing Outgoing Long-...

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

第六次全国动力气象学术会议

作者： Yongyun Hu department of atmospheric Sciences, School of physics, peking university Beijing, {4.

It is known that the Hadley cell is a thermally driven direct circulation,consisting of a rising of warm and moist air in the equatorial region and a descent ofcolder air in the subtropics,and that the Hadley cell tra...

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Science china Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2,3, SUN Yele1 & WANG Zifa3 1. The Center for atmospheric Environmental Study, department of Chemistry, Beijing Normal university, Beijing 100875, china 2. Center for atmospheric Chemistry Study, department of Environmental Science & Engineering, Fudan university, Shanghai 2004.3, china 3. LAPC/NZC, Institute of atmospheric physics, CAS, Beijing 100029, china 1. The Center for atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of atmospheric physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74. and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% （38%―86%） of the total mineral aerosols in TSP, 69% （52%―90%） in PM10, and 76% （59%―93%） in PM2.5 in spring, and 69% （52%―83%）, 79% （52%―93%）, and 4.% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.