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Sulfonic Acid Modified Hollow Silica Spheres and Its Application in Proton Exchange Membranes

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Journal of Wuhan university of Technology(Materials Science) 2011年第5期26卷 837-842页

作者：朱敏袁俊杰 School of Materials Science and engineering Tongji University Key Laboratory of Advanced civil engineering Materials Minstry of EduationTongji University

In order to improve the proton conductivity of hollow silica spheres （HSS）/perfluorosulfonic acid ion-exchange （PFSA） composite membranes as proton exchange membrane,sulfonic acid groups were grafted onto the surfaces of HSS via post grafting *** images and FT-IR spectra of the obtained sulfonic acid groups modified hollow silica spheres （SAMHSS） illustrated that the sulfonic acid groups were successfully grafted onto the surfaces of *** uptake and swelling degree of SAMHSS/PFSA composite membranes were found much higher than those of HSS/PFSA membranes due to the introduction of hydrophilic sulfonic acid *** a range from 50 ℃ to 130 ℃,the highest conductivity of composite membranes was obtained when 5 wt% SAMHSS was *** maximum conductivity reached 7.5×10-2.S·cm-1 at 100 ℃ and 100% relative humidity,even the temperature increased to 130 ℃,the conductivity of composite membranes with 5 wt% SAMHSS could reach 3.7×10-2.S·cm-1 at 100 % relative humidity,while the conductivity of the recast PFSA was only 2.2.10-3 S·cm-1.

关键词： composite hollow silica spheres proton exchange membrane sulfonation conductivity

Periods and Energy Dissipations of a Novel TLD Rectangular Tank with Angle-adjustable Baffles

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Journal of shanghai Jiaotong university(Science) 2008年第2期13卷 139-144页

作者：尚春雨赵金城 department of civil {2. Shanghai Jiaotong University

A novel tuned liquid damper (TLD) rectangular tank with two angle-adjustable baffles was pre- *** numerical analysis was performed using the commercial code *** standard kinetic energy and dissipation rate turbulent model was employed,which was solved using volume of fluid (VOF) method able to treat both the free surface motion and the viscous stresses over the rigid walls *** relationship between the natural periods of water and the angles of its baffles was studied by numerical sim- ulating of a case,and the changes of energy dissipations were *** natural periods and dampers of the novel TLD can be changed in a wide range by adjusting the baffles' angle,thus it is more effective in controlling the vibration of structures in a wide frequency range.

关键词： tuned liquid damper angle-adjustable baffle turbulent eddies energy dissipation

Tracheal compliance and limit flow rate changes in a murine model of asthma

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Science china(Life Sciences) 2008年第10期51卷 922-931页

作者： TENG ZhongZhao1, WANG YiQin2. LI FuFeng2. YAN HaiXia2.& LIU ZhaoRong3 1 department of Mathematical Sciences, Worcester Polytechnic Institute, Worcester, MA, 01609, USA 2.Syndrome Laboratory of TCM, shanghai university of Traditional Chinese Medicine, {2. 2.12.3, china 3 department of Mechanics and engineering Science, Fudan university, {2. 2.0433, china department of Mathematical Sciences Worcester Polytechnic Institute Worcester USA Syndrome Laboratory of TCM Shanghai University of Traditional Chinese Medicine Shanghai China department of Mechanics and engineering Science Fudan University Shanghai China

Trachea is the unique passage for air to flow in and out. Its tone is of importance for the respiration system. However, investigation on how tracheal tone changes due to asthma is limited. Aiming at studying how the mechanical property changes due to asthma as well as the compliance and flow limitation, the following methods are adopted. Static and passive pressure-volume tests of rats' trachea of the asthmatic and control groups are carried out and a new type of tube law is formulated to fit the experimental data, based on which changes of compliance and limit flow rate are investigated. In order to give explanation to such changes, histological examinations with tracheal soft tissues are made. The results show that compliance, limit flow rate and material constants included in the tube law largely depend on the longitudinal stretching ratio. Compared with the control group, the tracheal compliance of asthmatic animals decreases significantly, which results in an increased limit flow rate. Histological studies indicate that asthma can lead to hyperplasia/hypertrophy of smooth muscle cells, and increase elastin and collagen fibres in the muscular membrane. Though decreasing compliance increases sta- bility, during the onset of asthma, limit flow rate is much smaller due to the lower transmural pressure. Asthma leads to a stiffer trachea and the obtained results reveal some aspects relevant to asthma-induced tracheal remodelling.

关键词： trachea asthma collapse tube law compliance limit flow rate remodelling

Modeling of multi-inclusion composites with interfacial imperfections:Micromechanical and numerical simulations

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Science china(Technological Sciences) 2010年第3期53卷 720-730页

作者： CHEN WeiQiu 1,ZHU XingYi 2.&HUANG ZhiYi 2.1 department of engineering Mechanics,Yuquan Campus,Zhejiang {2.,Hangzhou 31002.,china 2.Key Laboratory of Soft Soils and Geoenvironmental engineering,Ministry of Education department of civil engineering,Zijingang Campus,Zhejiang {2.,Hangzhou 310058,china department of engineering Mechanics Yuquan Campus Zhejiang University Hangzhou China Key Laboratory of Soft Soils and Geoenvironmental engineering Ministry of Education Hangzhou China department of civil {2. Zijingang Campus Zhejiang University Hangzhou China

A micromechanical approach based on a two-layer built-in model and a numerical simulation based on boundary element method are proposed to predict the effective properties of the multi-inclusion composite with imperfect *** spring model is introduced to simulate the interface *** two methods are compared with each other,and good agreement is *** effects of interface spring stiffness,volume ratio and stiffness of inclusions on the micro-and macro-mechanical behaviors of fiber-reinforced composites are *** is shown that the developed micromechanical method is very comprehensive and efficient for fast prediction of effective properties of composites,while the numerical method is very accurate in detailed modeling of the mechanical behavior of composites with multiple inclusions.

关键词： micromechanics boundary element method interface multi-inclusion composite effective elastic property

CERAMIC MATRIX COMPOSITE SYNTHESIZED BY THE PURE Al+NaOH SELF-OXIDATION

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 296-302页

作者： S.X. He1), S. Yuan2., J. Wang1) and B.D. Sun1) 1) department of Marterials Science and engineering, {2. Jiao Tong university, {2. 2.0030, china 2. department of Marterials Science and Engineerin Dept. of Mat. Sci. Shanghai Jiaotong Univ. Shanghai 200030 China

An Al2.3 ceramic matrix composite was fabricated by self-oxidation of pure Al+NaOH, and its microstructure, mechanical properties and growth mechanism were analyzed. Experimental results show that the composite possesses better mechanical properties, higher density and faster growth velocity than that made of Al-Mg-Si alloy. The composite grows primarily along the crucible wall and its microstructure is characterized by a periodic wavy like structure.

关键词： Aluminum Caustic soda Oxidation Synthesis (chemical)

Amphiphilic dendronized homopolymers

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Science china Chemistry 2010年第12期53卷 2509-2519页

作者： LI Wen 1 & ZHANG AFang 1,2.1 Institute of Polymers,department of Materials,ETH Zurich,Wolfgang-Pauli-Str.10,8093 Zurich,Switzerland 2.department of Polymer Materials,College of Materials Science and {2.,shanghai university,shanghai 2.1800,china Institute of Polymers Department of Materials ETH Zurich Zurich Switzerland department of Polymer Materials College of Materials Science and Engineering Shanghai University Shanghai China

A series of second generation of amphiphilic dendronized homopolymers are efficiently synthesized,and their thermoresponsiveness in aqueous solutions and secondary structures in methanol solutions are *** polymers are constructed in each repeat unit with various generations of hydrophobic 4-aminoproline and hydrophilic oligoethylene glycol (OEG)-based dendrons,and their over-all hydrophilicity is tuned by varying these dendron *** with or without the first generation of proline dendron show good water solubility at room temperature,but exhibit typical thermoresponsive behaviors at elevated temperatures as characterized by turbidity measurements using UV-vis spectroscopy,while the polymer with the secondary generation of proline dendron is not soluble in *** polymers show ordered secondary structures as evidenced by the optical rotation and circular dichroism ***,assembly of these amphiphilic homopolymers into porous films via breath figure (BF) technique is described,and polymer structures are found to show significant influence on the morphology of porous film.

关键词： amphiphilic polymer dendronized polymer dendritic macromolecule supramolecular structure

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-2.1, shanghai 2.1800,{2. 2. department of Physics, Shandong Normal university, Jinan 2.0014,{2. 3. Shandong Institute of Architecture and engineering, Jinan 2.0014,{2. shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciencesshanghai{2. department of PhysicsShandong Normal universityJinan{2. Shandong Institute of Architecture and engineeringJinanchina

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Multiresolution Terrian Model in GIS

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测绘学报 2002年第Z1期31卷 92-98页

作者： ZHANG Jin 1,TONG Xiao hua 2.(1. department of Surveying and Mapping, Taiyuan university of Technology, Taiyuan 03002.,{2. 2. department of Surveying and Geo informatics, Tongji university, shanghai 2.0092.{2.) department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 department of Surveying and Geo-informatics Tongji University 上海 200092

DEM, which becomes a major component of geographic information processing in earth and engineering sciences, has been studied in the GIS literature for a long time. We use DEM to represent the terrain in GIS. The more data are available, the better representations of a terrain can be built. But not all tasks in the framework of a given application necessarily require the same accuracy, and even a single task may need different levels of accuracy in different areas of the domain. Multiresolution models, such as LOD, offer the possibility of representing and analyzing a terrain at a range of different levels of detail. In this paper, some key issues in multiresolution DEM model are studied. Three main models are focused on Hierarchical TIN(HTIN), multiresolution terrain model based Delaunay and Hierarchical Dynamic Simplification. The advantages and disadvantages of these methods are analyzed. The technology of tile to tile edge match is studied to maintain the consistency between adjacent edges and tile edges in HTIN model. And the Hypergraph based Objected oriented Model(HOOM) is presented to divide and code spatial area and describe the terrain feature in adding and deleting points based on Delaunay rule retriangulating. The conclusions have been drawn in the end.

关键词： DEM multiresolution LOD GIS

Modeling the Flexural Carrying Capacity of Corroded RC Beam

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Journal of shanghai Jiaotong university(Science) 2008年第2期13卷 129-135页

作者：王小惠刘西拉 department of civil {2. Shanghai Jiaotong University

Considering the change of bond strength between corroded steel and concrete,flexural carrying ca- pacity of corroded reinforced concrete (RC) beam was *** the basis of the condition of equilibrium of forces and compatibility of deformations for the whole beam,a model for the prediction of flexural carrying capacity of the corroded RC beam was *** of the model's predictions with the experimental results published in the literature shows the practicality of the proposed method.

关键词： bond strength flexural capacity mechanical behavior corroded reinforced concrete beam