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Science China Chemistry 2004年第5期47卷 388-395页

作者： ZHANG Xingwen1,2, HU Lijiang1, HUANG Yudong1, SUN Dezhi2 & SUN Yi3.1. department of Applied Chemistry,harbin institute of technology, HUANG Yudong, harbin 150001, China 2. department of Environmental Engineering, harbin institute of technology, harbin 150001, China 3. department of experimental mechanics,harbin institute of technology, harbin 150001, China 1. department of Applied Chemistry Harbin Institute of Technology HUANG Yudong 150001 Harbin China 2. department of Environmental Engineering Harbin Institute of Technology 150001 Harbin China 3. department of experimental mechanics Harbin Institute of Technology 150001 Harbin China

The organic/inorganic hybrid nanostructural vinylsilsesquioxanes (VSSO) were prepared from the hydrolytic condensation of vinyltrimethoxysilane (VMS). The proposed formu- las of VSSO were assigned with standard spectroscopic techniques, FTIR, NMR (1H, C and 13.29Si) and MALDI-TOF MS, and a generic formula of the SSO, Tn(OH)x(OR’)y(x, y = 0, 1, 2…; n = 1, 2…; T = RSiO1.5 ?(x+y)/2n). Geometric parameters (Si-O and Si-C bond lengths, Si-O-Si and O-Si-O bond angles) and total energies of the multi-structures of VSSO were calculated by a quantum mechanical investigation and molecular symmetries. According to the results of the calculation, most molecules had stabler ladder structures than the cage isomers, therefore, the most probably reasonable and optimum structure of the VSSO system was the ladder type.

关键词： vinyltrimethoxysilane (VMS), silsesquioxanes (SSO), sol-gel process, quantum mechanical calculation, MNDO.

A LOWER BOUND APPROACH TO THE YIELD LOCI OF POROUS MATERIALS

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Acta Mechanica Sinica 1989年第3期5卷 237-243页

作者： Sun Yi Wang Duo(department of Applied mechanics,harbin institute of technology) 1. department of Applied mechanics Harbin Institute of Technology China

A lower bound approach is proposed for the first time to solve the macroscopic yield loci of porous *** results are then compared with Gurson's upper bound yield loci and those of the *** is shown that the present ana... 详细信息

关键词： constitutive equations porous materials ductile damage lower bound analysis method

ANALYSIS OF SHEAR LOCALIZATION IN POROUS MATERIALS

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Acta Mechanica Sinica 1990年第1期6卷 29-34页

作者： Sun Yi Wang Duo, department of Applied mechanics, harbin institute of technology 1. department of Applied mechanics Harbin Institute of Technology Harbin China

A set of constitutive equations are derived based on the authors'lower bound yield loci for porous materials. By using these equations, the conditions for shear localization in porous materials are then investigated and the results are compared with those of Gurson's equations and the finite element analysis. The advantages of the present constitutive equations are fully illustrated.

关键词： constitutive equations shear localization analysis porous materials ductile fracture

UNSTEADY SUPERCAVITATING FLOW PAST CONES

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Journal of Hydrodynamics 2006年第3期18卷 262-272页

作者： HU Chao YANG Hong-lan ZHAO Cun-bao HUANG Wen-hu institute of Aerospace Engineering and Applied mechanics Tongji Universtity Shanghai 200092 China department of Aerospace Engineering and mechanics Harbin Institute of Technology Harbin 150001 China department of Aerospace Engineering and mechanics Harbin Institute of Technology Harbin 150001 China

Based on integral equation method, the study of unsteady supercavitating flow past cones is presented. The shape and length of supercavity are calculated respectively using the finite difference time discretization method. The characteristics of the shape and length of supercavities, which vary with the cone＇s angle and cavitation number, are investigated respectively, the varied features of some supercavity scales are analyzed when the flow field is perturbed periodically. The curves relationship between cavity length and cavitation number, which are based respectively on present method and other theories, are discussed and compared. It is obviously shown that the supercavity changes have two characteristics： retardance and wave. These results obtained would be useful in the case of design and analysis of cavitator under water.

关键词： supercavitation cavitator unsteady flow,slender body theory integral equation method

PLANE STRESS DYNAMIC FIELDS NEAR A PROPAGATING CRACK-TIP IN A POWER-LAW MATERIAL

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Acta Mechanica Sinica 1988年第1期4卷 22-34页

作者： Zhang Zimao Gao Yuchen harbin Shipbuilding Engineering institute, harbin. China Now at {3. of mechanics, harbin institute of technology, harbin, China. 1. harbin Shipbuilding Engineering institute Harbon China

Based on the plastic-dynamic equations, the asymptotic behaviour of the near-tip fieldsfor a plane stress tensile crack propagating in a power-law material has been studied in this paper, It isshown that the stress and strain singularities are, respectively, of the order (In A/r)~(1/(n-1)) and(In A/r)~(n/(n-1)).where A is a constant which is related to the size of plastic region, r is the distance to the crack tip, n isthe power-law exponent.

关键词： power-law material strain singularity singularity-factor elastic region plasticregion.

DYNAMIC ANALYSIS OF A BURIED RIGID ELLIPTIC CYLINDER PARTIALLY DEBONDED FROM SURROUNDING MATRIX UNDER SHEAR WAVES

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Acta Mechanica Solida Sinica 1995年第1期8卷 51-63页

作者： Wang Yuesheng Wang Duo, department of Astronautics and mechanics, harbin institute of technology, {3. 150001, P. R. China department of Astronautics and mechanics Harbin Institute of Technology Harbin 150001 China

This paper investigates the dynamic behavior of a buried rigid elliptic cylinder partially debonded from surrounding matrix under the action of anti-plane shear waves (SH waves). The debonding region is modeled as an elliptic arc-shaped interface crack with non-contacting faces. By using the wave function (Mathieu function) expansion method and introducing the dislocation density function as an unknown variable, the problem is reduced to a singular integral equation which is solved numerically to calculate the near and far fields of the problem. The resonance of the structure and the effects of various parameters on the resonance are discussed.

关键词： elastic wave scattering interface debonding interface crack wave function singular integral equation

MICROSTRUCTURE　AND　TENSILE　PROPERTIES　OF　RAPIDLY　SOLIDIFIED　Al－3.8Li－0．8Mg－0．4Cu－0．13.r　ALLOY　PREPARED　BY　SPRAY　DEPOSITION

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 37-43页

作者： CUI Chengsong FAN Hongbo SHEN Jun JIANG Zuling LI Qingchun(department of Metallic Materials and technology,harbin institute of technology,{3. 150001,China) harbin Inst of technology Harbin China

Al-3.8Li-0.8Mg-0.4Cu-0.13.r alloy was prepared by a novel spray deposition technique,and its microstructure and tensile properties after various aging treatments have been investigated. The experimental results show that the alloy,under study has very fine equiaxed grains about 5-20μm in diameter and a relative density of(94±3.% on *** in the as-extruded alloy are'brick-like'in morphology,and few oxide particles have been found al the grain boundaries.δ' particles with irregular shape and'δ'-β''coprecipitates appear in the aged *** coarsening of δ'particles is fast,and the distance between the particles does not widen so obviously as that of IM(ingot-casting method) alloys with increasing aging *** spray deposited Al-Li *** the peak-aged condition in a short time(10 h al 190℃) when the best properties(σb=53. MPa, σ0.2=480 MPa.δ=10%) are *** with RSPM(rapid solidification processing method)Al-Li alloy,the ductility of the tested alloy has been *** while a comparable tensile strength is maintained.

关键词： spray deposition rapid solidification Al-Li alloy microstructure tensile property

Catalysts for decomposing ozone tail gas

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Journal of Environmental Sciences 2003年第6期15卷 779-782页

作者： LIU Chang-an, SUN De-zhi, WANG Hui, LI Wei (department of Environmental Science and Engineering, harbin institute of technology, harbin 150001,China. department of Environmental Science and Engineering Harbin Institute of Technology Harbin 150001

The preparation of immobilizing-catalysts for decomposing ozone by using dipping method was studied. XRD, XPS and TEM were used to characterize the catalysts. The three kinds of catalysts were selected preferentially, and their catalytic activities were investigated. The results showed that the catalyst with activated carbon dipping acetate(active components are Mn:Cu=3.2, active component proportion in catalyst is 15%, calcination temperature is 200℃) has the best catalytic activity for ozone decomposing. One gram of catalyst can decompose 17.6 g ozone at initial ozone concentration of 2.5 g/m 3.and the residence time in reactor of 0.1 s. The experimental results also indicated that humidity of reaction system had negative effect on catalytic activity.

关键词： ozone tail gas catalytic decomposition immobilizing-catalyst MnO 2 CuO

Microstructure and Strength of Laser Welds of Sub-micron Particulate-reinforced Aluminum Matrix Composite Al_2O_(3.)/6061Al

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Rare Metals 2001年第3期20卷 178-182页

作者： Liming Liu, Jitai Niu 1) department of Materials Engineering, Dalian University of technology. Dalian 116024, China 2) National Key Laboratory of Advanced Welding Production technology, {3.,harbin 150001, China 大连理工大学辽宁大连 116024 哈尔滨工业大学现代焊接生产技术国家重点实验室黑龙江哈尔滨 150001

The microstructure of laser welds of sub-micron particulate-reinforced aluminum matrix composite Al_2O_(3.)/6061Al and the weldability of the material were studied. experimental results indicated that because of the huge specific surface area of the reinforcement, the interfacial reaction between the matrix and the reinforcement was re- strained intenslvely at elevated temperature and pulsed laser beam. The main factor affecting the weldability of the com- posite was the reinforcement segregation in the weld resulting from the push of the liquid/solid interface during the soli- dification of the molten pool. The laser pulse frequency directly affected the reinforcement segregation and the reinfor- cement distribution in the weld, so that the weldability of the composite could be improved by increasing the laser pulse frequency. On the basis of this, a satisfactory welded joint of sub-micron paniculate-reinforced aluminum matrix com- posite Al_2O_(3.)/6061Al was obtained by using appopriate welding parameters.

关键词： sub-micron particulate-reinforced aluminum matrix composite laser welding welded joint reinforced matrix

Hybrid Optical-Electronic Implementation of Morphological Edge Detection

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Chinese Journal of Lasers 1994年第1期B3卷 83-90页

作者： YUAN Shifu ZHANG Xueru ZHAO Shijie LI Yan CHEN Lixue(department of Applied Physics,harbin institute of {3.,harbin 150001,China) harbin Inst of technology Harbin China

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关键词： edge detection morphological transformation optical information processing