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Steady-state responses of axially accelerating viscoelastic beams: Approximate analysis and numerical confirmation

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Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1707-1721页

作者： CHEN LiQun1,2.& DING Hu2.1 Department of Mechanics, shanghai university, shanghai 2.0444, china 2.shanghai Institute of Applied Mathematics and Mechanics, shanghai 2.0070, china Department of Mechanics Shanghai University Shanghai 200444 China shanghai Institute of Applied Mathematics and Mechanics Shanghai 200070 China

Nonlinear parametric vibration of axially accelerating viscoelastic beams is inves-tigated via an approximate analytical method with numerical confirmations. Based on nonlinear models of a finite-small-stretching slender beam moving at a speed with a periodic fluctuation, a solvability condition is established via the method of multiple scales for subharmonic resonance. Therefore, the amplitudes of steady-state periodic responses and their existence conditions are derived. The amplitudes of stable steady-state responses increase with the amplitude of the axial speed fluctuation, and decrease with the viscosity coefficient and the nonlinear coefficient. The minimum of the detuning parameter which causes the existence of a stable steady-state periodic response decreases with the amplitude of the axial speed fluctuation, and increases with the viscosity coefficient. Nu-merical solutions are sought via the finite difference scheme for a nonlinear par-tial-differential equation and a nonlinear integro-partial-differential equation. The calculation results qualitatively confirm the effects of the related parameters pre-dicted by the approximate analysis on the amplitude and the existence condition of the stable steady-state periodic responses. Quantitative comparisons demonstrate that the approximate analysis results have rather high precision.

关键词： nonlinearity parametric vibration axially accelerating beam method of multiple scales numerical confir-mation

A new scheme of digital communication using chaotic signals in MIMO channels

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Science china(Information Sciences) 2012年第10期55卷 2183-2193页

作者： MA HuanFei 1 & KAN HaiBin 2.1 School of Mathematical Sciences,Soochow university,Suzhou 2.5006,china 2.School of Computer Science,{2. university,shanghai 2.0433,china 1. School of Mathematical Sciences Soochow University Suzhou 215006 China 2. School of Computer Science Fudan University Shanghai 200433 China

This paper proposes a new digital communication scheme,which uses chaotic signals based on the adaptive synchronization and parameter identification technique of chaotic systems reported *** to the multi signal character,this scheme combines the chaotic signal transmission with the MIMO channel technique in a wireless environment,which is different from the traditional chaotic communication *** a practical perspective,an outline of modulation,channel model,demodulation and non-coherent detection is ***,system performance is evaluated by simulations,and improvements on this scheme are also discussed.

关键词： chaotic modulation chaotic digital communication mapping parameters MIMO channel

Distribution of nimodipine in brain following intranasal administration in rats

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Acta Pharmacologica Sinica 2004年第4期25卷 124-129页

作者： Qi-zhi ZHANG, Xin-guo JIANG2. Chun-hua WU Department of Pharmaceutics, School ofPharmacy, fudan university, shanghai 2.0032.{2. Department of Pharmaceutics School of Pharmacy Fudan University

AIM: To determine whether nasally applied nimodipine (NM) could improve its systemic bioavailability and be transported directly from the nasal cavity to the brain. METHODS: NM was administered nasally, intravenously (iv), and orally to male Sprague-Dawley rats. At different times post dose, blood, cerebrospinal fluid (CSF), and brain tissue samples were collected, and the concentrations of NM in the samples were analyzed byHPLC. RESULTS: Oral systemic bioavailability of NM in rats was 1.17 %, nasal dosing improved bioavailibility to 67.4 %. Following intranasal administration, NM concentrations in olfactory bulb (OB) within 30 min post dose were found significant higher than in the other brain tissues. However, similar NM levels in different brain regions were observed after iv injection. AUC in CSF and OB from the nasal route was 1.2. and 1.39 fold compared with the iv route, respectively. The brain-to-plasma AUC ratios were significantly higher after nasal administration than after iv administration (P<0.01). CONCLUSION: Nasally administered NM could markedly improve the bioavailability and a fraction of the NM dose could be transported into brain via the olfactory pathway in rats.

关键词： intranasal administration nimodipine olfactory bulb olfactory pathways

PIXE and INAA studies on ancient potteries from Guangfulin relics in shanghai

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Progress in Natural Science:Materials International 2007年第11期17卷 1348-1356页

作者： Lin Jiawei1, Cheng Huansheng1, Zhang Zhengquan1, Zhang Bin1, Feng Songlin2. Song Jian3, Gao Menghe4 and Zhu Dan1(1. Applied Ion Beam Physics Laboratory, Key Laboratory of the Ministry of Education, Institute of Modern Physics, fudan university, shanghai 2.0433,{2. 2. Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, Beijing 100039,{2. 3. shanghai Museum, shanghai 2.0003,{2. 4. Department of Cultural Heritage and Museology, fudan university, shanghai 2.0433,{2.) Applied Ion Beam Physics Laboratory Key Laboratory of the Ministry of Education Institute of Modern Physics Fudan University Shanghai 200433 China Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Beijing 100039 China shanghai Museum Shanghai 200003 China Department of Cultural Heritage and Museology Fudan University Shanghai 200433 China

This paper reports the study of ancient potteries unearthed from the Guangfulin site in shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: Liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were produced in the same place. Proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This supports the archaeologists’ speculation that a group of ancient people migrated to shanghai from some other places 4000 years ago.

关键词： PIXE INAA factor analysis Guangfulin ancient pottery

Low-heating solid state synthetic reactions of cyclopeantadienyl organolanthanide complexes

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Chinese Science Bulletin 2003年第19期48卷 2041-2043页

作者： ZHU Ming1, LI Yanrong1, LUO Jun1 & ZHOU Xigeng1,2.1. Department of Chemistry, fudan university, shanghai 2.0433,{2. 2. State Key Laboratory of Organometallic Chemistry, shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, shanghai 2.0032.{2. Department of Chemistry Fudan University China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai China

A novel and simple one-step, solid state reaction of multicomponent systems has been developed to synthesize cyclopentadienyl-containing organolanthanide complexes, in which the effects of the coordinated solvent molecules and the nature of the reactants were also studied. We also studied the solid state decomposition reaction of Cp2.bPz(HPz), and the formation of [CpYb(Pz)2.2.may indicate that the constrained environment in solid state can lead to a novel chemical transformation, with product selectivity possibly different from that in the liquid phase.

关键词：低热固态反应合成茂基有机镧系络合物绿色化学环戊二烯 [CpYb(Pz)2.2 Cp2.bPz(HPz) 镱配合物

Mass spectrometry analysis of melanoma related O-glycans in sera

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Science china Chemistry 2010年第4期53卷 807-811页

作者： BAI Chen1,4, WU Gang1 & ZHAO Liang2.3 1Department of Life Science, fudan university, shanghai 2.0433,{2. 2.epartment of Chemistry, fudan university, shanghai 2.0433,{2. 3Institutes of Biomedical Sciences, fudan university, shanghai 2.0433,{2. 4Department of Food Science, shanghai Business School, shanghai 2.02.5,{2. 1. Department of Life Science Fudan University Shanghai 200433 China4. Department of Food Science Shanghai Business School Shanghai 200235 China2. Department of Chemistry Fudan University Shanghai 200433 China3. Institutes of Biomedical Sciences Fudan University Shanghai 200433 China

Glycomics comparison was carried out by screening melanoma serum biomarkers between C57 mice with and without B16 implanted. O-glycans were released from 10 μL sera by β-elimination, purified by Graphitized Carbon Cartridge Solid Phase Extraction (GCC-SPE) and analyzed by MALDI-QIT-TOF-MS. MS raw data were acquired and exported by Launchpad software. MATLAB was then applied for further data analysis. 10 Glycans were considered to have stable changes after B16 implantation and 5 of them were under structural analysis via MS/MS.

关键词： mass spectrometry glycomics melanoma biomarkers

Numerical Computation of High Dimensional Solitons Via Darboux Transformation

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 248-252页

作者： Zixiang ZHOU (Institute of Mathematics,fudan university,{2. 2.0 0 433,china) E- mail:zxzhou@*** Institute of Mathematics Fudan University Shanghai 200433 China

Darboux transformation gives explicit soliton solutionsof nonlinear partial differential equations. Using numerical computation in each step of constructing Darboux transformation,one can get the graphs of the solitons ***(n 3) , this method greatly increases the speed and deduces the memory usage of computation comparing to the software for algebraic computation. A technical problem concerning floating overflow is discussed.

关键词： Darboux transformation numerical computation

Generation of large fifth-order nonlinear phase shifts by use of lossless χ^((2.) cascaded nonlinear processes

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 1-7页

作者： XU Guang1, QIAN Liejia2. WANG Tao2. FAN Dianyuan1,2.& LI Fuming2.1. shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, shanghai 2.1800,{2. 2. State Key Laboratory for Advanced Photonic Materials and Devices, fudan university, shanghai 2.0433,{2. Correspondence should be addressed to Xu Guang (email: xuguany@***) Received March 9, 2.03 1. shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences 201800 Shanghai China 2. State Key Laboratory for Advanced Photonic Materials and Devices Fudan University 200433 Shanghai China

It is shown that the cascaded fifth-order nonlinear phase shifts will increase with energy loss in the cascaded processes. Essentially different from the multi-photon absorption accompanied with inherent material nonlinearities, the loss of fundamental wave in a cascaded process is controllable and suppressible. By introducing difference frequencies generated from the reaction between the fundamental and its second harmonic after the cascaded processes, the fundamental wave can be free of energy loss, while the large cascaded fifth-order nonlinear phase shift is maintained.

关键词： cascaded nonlinear phase shifts, phase mismatching, harmonic conversions.

Chinese Jingdezhen blue and white imperial porcelain

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Science china(Technological Sciences) 2004年第3期47卷 366-375页

作者： WU Juan1, LI Jiazhi1, DENG Zequn1 & WANG Changsui2.1. Laboratory of Ancient Ceramics, shanghai Institute of Ceramics, Chinese Academy of Sciences, shanghai 2.0050,{2. 2. Department of History of Science and Archaeometry, university of Science and Technology of{2., Hefei 2.002.,{2. Chinese Acad Sci Shanghai Inst Ceram Lab Ancient Ceram Shanghai 200050 Peoples R China Univ Sci & Technol china Dept Hist Sci Archaeometry Hefei 230026 Peoples R China

Jingdezhen blue and white imperial porcelain specimens from the Yuan, Ming and Qing dynasties have been systematically analyzed using a nondestructive test method—— energy dispersive X-ray fluorescence analysis (EDXRF). The derived data of major and trace element compositions have been treated by correspondence analysis. The variation laws of the composition patterns for Jingdezhen blue and white imperial porcelain in different historical periods owing to the change in raw materials, recipe and technology have been discussed, and a time model related to variation of element composition has been preliminarily established, It would be helpful for scientific dating of Jingdezhen blue and white imperial porcelain, and even for the studies on the whole field of identification of ancient ceramics.

关键词： energy dispersive X-ray fluorescence analysis, blue and white imperial porcelain, correspondence analysis.