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Effect of surface nanocrystallization on the corrosion behavior of Zircaloy-4

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Science China(Technological Sciences) 2009年第8期52卷 2227-2231页

作者： ZHU YuTao1,2 & ZHANG XiYan1,2,3.1 college of Materials Science and engineering, Chongqing university, Chongqing 400045, China 2 National engineering Research Center for Magnesium Alloys, Chongqing university, Chongqing 400044, China 3.School of Physical Science and engineering technology, Guangxi university, Nanning 53.004, China college of Materials Science and engineering Chongqing University Chongqing China National engineering Research Center for Magnesium Alloys Chongqing University Chongqing China School of Physical Science and engineering technology Guangxi University Nanning China

The contrastive corrosion experiments between surface nanocrystallined Zircaloy-4 and coarse-grained Zircaloy-4 under the condition of 673.K/10.3.MPa in pure water are carried out, and the microstructure of oxide films has been studied. The results indicate that the growth rate of oxide films formed on the nanocrystalline Zircaloy-4 is lower than that of oxide films formed on the coarse-grained Zircaloy-4. Simultaneously, the oxide/metal interface of the former is more regular and glossy than that of the latter. For nanocrystalline Zircaloy-4, the low oxygen diffusion rate through the oxide/metal interface can hinder the reaction of oxygen ion with metal ion. Furthermore, more tetragonal ZrO2 are observed in the oxide films, which can delay the martensite phase transition from tetragonal to monoclinic phase in oxide films.

关键词： nanocrystalline Zircaloy oxide film microstructure

The band structures of BSb and B_xGa_(1-x)Sb alloys

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Science China(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2, WANG Qi3. LUO Li1, HUANG YongQing3.& REN XiaoMin3.1 School of Physics and Optoelectronic engineering, Guangdong university of technology, Guangzhou 510006, China 2{3. of Information engineering, Zhejiang university of technology, Hangzhou 3.003., China 3.Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education, Beijing university of Posts and Telecommunications, Beijing 100876, China School of Physics and Optoelectronic engineering Guangdong University of Technology Guangzhou China college of Information engineering Zhejiang University of Technology Hangzhou China Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

Study on the stability and 3.dimensional character for natural convection in a rectangular cavity heated from below

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Science China(Technological Sciences) 2010年第6期53卷 1647-1654页

作者： ZHAN NaiYan1,2,XU PeiWei1,SUN ShiMei,YANG Mo2 & LIU Jun3.1 Scool of Municipal and Environmental engineering,Jilin Institute of Architectural and Civil engineering,Changchun 13.021,China 2 college of Power engineering,university of Shanghai for Science and technology,Shanghiai 200093.China 3.college of Power engineering,Jilin university,Changchun 13.000,China Scool of Municipal and Environmental engineering Jilin Institute of Architectural and Civil Engineering Changchun China college of Power engineering University of Shanghai for Science and Technology Shanghiai China college of Power engineering Jilin University Changchun China

Natural convection of air is numerically simulated in a 3.dimensional rectangular cavity heated from below using SIMPLE algorithm with a QUICK *** results suggest that when all lateral walls are adiabatic,the fluid rolls occur along the long *** the Rayleigh number is smaller,the flow is of 2-dimensional character,and the rolls shapes are *** average Nusselt numbers in the central part of the cavity are *** average Nusselt numbers in the part near by the cavity are *** to the comparison of 3.dimensional results with 2-dimensional results,the flow patterns and heat transfer in the central part of the cavity can be assumed as a 2-dimensional flow,While those in the part near by the cavity can *** increasing Rayleigh number,the flow is 3.dimensional *** 3.dimensional result accords with the experimental *** all lateral walls are adiabatic,the ten rolls occur along the long *** when lateral walls are heated or cooled,the rolls disappear along the long axis and two rolls occur along the short *** rotation direction of the rolls is *** Rayleigh number is over some critical value,flow and heat transfer will be asymmetry,indicating unsteady oscillation *** nonlinear analyses,it is shown that with increasing Rayleigh number,flow and heat transfer will change from steady state to unsteady state through HOPF bifurcation,and transition to chaos will occur through multi-periodical oscillation.

关键词： Critical Raleigh number 3.dimensional character lateral boundaries nonlinear characteristic bifurcation

Cross-linked Polyethylenimine as Potential DNA Vector for Gene Delivery with High Efficiency and Low Cytotoxicity

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 780-787页

作者： Wei DONG~(1,2) Guang-Hui JIN~1 Shu-Feng LI~(1,3. Qi-Ming SUN~1 Ding-Yuan MA~1 Zi-Chun HUA~1 1 State Key Laboratory of Pharmaceutical Biotechnology,college of Life Science,Nanjing university,Nanjing 210093.China 2 School of Chemical{3. Nanjing university of Science and technology,Nanjing 210094,China 3.college of Basic Medical Science,Southeast university,Nanjing 210009,China State Key Laboratory of Pharmaceutical Biotechnology College of Life Science Nanjing UniversityNanjing 210093 China School of Chemical engineering Nanjing University of Science and TechnologyNanjing 210094 China college of Basic Medical Science Southeast UniversityNanjing 210009 China

Polyethylenimine (PEI) has been known as an efficient gene carrier with the highest cationiccharge *** transfection efficiency of PEI,along with its cytotoxicity,strongly depends on itsmolecular *** enhance its gene delivery efficiency and minimize cytotoxicity,we have synthesizedsmall cross-linked PEI with biodegradable linkages and evaluated their transfection efficiencies in *** study,branched PEI with a molecular weight of 800 Da was cross-linked by small diacrylate[1,4-butanediol diacrylate or ethyleneglycol dimethacrylate (EGDMA)] for 2-6 *** efficiencies of thecross-linked PEI in in vitro transfection of plasmid DNA containing enhanced green fluorescent protein(EGFP) reporter gene were assessed in melanoma B 16F10 cell line and other cell *** cytometrywas used to quantify the cellular entry efficiency of plasmid and the transgene expression *** of the cross-linked PEI in these cells were evaluated by MTT ***-PEI 800-4h,atypical cross-linked PEI reported here,mediated a more efficient expression of reporter gene than thecommercially available 25-kDa branched PEI control,and resulted in a 9-fold increase in gene deliveryin B16F10 cells and a 16-fold increase in 293. cells,while no cytotoxicity was found at the optimizedcondition for gene ***,the transfection activity of polyplexes was preserved in thepresence of serum proteins.

关键词： polyethylenimine gene delivery cytotoxicity B16F10 293. cell line

The Properties of Solution Precursor Plasma Spray Nanostructured Thermal Barrier Coatings

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Journal of wuhan university of technology(Materials Science) 2010年第6期25卷 924-928页

作者：闵捷 State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology

About 3.0 μm thickness uniform thermal barrier coatings （TBCs） were deposited on the 1Cr18Ni9Ti samples by solution precursor plasma spray （SPPS）.The analysis methods,such as TEM,SEM,and XRD were used to characterize the coatings in the aspects of microstructure and phase *** samples were quenched from 1121 ℃ to room temperature by forced-air to measure the thermal cycling *** density were measured by means of water *** experimental results show that grain size of the SPPS TBCs is about 3. nm with desired tetragonal phase ZrO2,and the SPPS TBCs（with 16% porosity） consist of arcuate pores,gelatin and melted *** hardness of the coatings is HR45Y3..5 and bond strength between coatings and substrates is 24.2 *** thermal shock test show the coatings have a average life of 500 cycles which is about 2.5 times than that of conventional air plasma spray （APS） TBCs.

关键词： SPPS TBCs nanostructure properties

Formation of the Inclusion Complex of Orange Ⅱ with β-Cyclodextrin and Its Photostability

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wuhan university Journal of Natural Sciences 2003年第4期 1147-1152页

作者： Lu Ping 1,2 , Liu Bin 1,3., Zhang Zhe 1 , Wu Feng 1 , Deng Nan-sheng 1 1. college of Resource and Environmental Science, wuhan university, wuhan 43.072, hubei, China 2. School of Chemistry and Environmental engineering, Jianghan university , wuhan 43.056, hubei, China 3. Department of Environmental and Chemical engineering, Huangshi Polytechnic college, Huangshi 43.003. hubei, China

Inclusion complex of Orange II with β-Cyclodextrin （β-CD） and the anti-photolysis effect under UV-light were investigated. The molar ratio of inclusion complex of β-Cyclodextrin and Orange Ⅱ is 1∶1. The formation constant K=1.23.×10 3.L/mol was determined by the UV and Fluorescence spectra respectively, which was quite in accordance with the calculation with a modified Benesi-Hildbrand equation. The inclusion complex was characterized by the IR spectra and the molar ratio of inclusion complex is 1∶1 too. The formation constant K=1.266×10 3.L/mol was determined by 1 H NMR analysis and was nearly the same by UV and fluorescence spectra. The photocatalytic decolorization rate of Orange Ⅱ solutions containing β-CD and TiO_ 2 was smaller by 51.9% than that of the Orange Ⅱ solutions only containing TiO_ 2 , while in the case of direct photolysis of Orange Ⅱ solutions, β-CD can lower the photolysis rate by 48.1% under UV-light. This result indicates β-CD can inhibit the photolysis and photocatalytic decolorization of Orange Ⅱ under UV-light. The β-CD inclusion complex was found to be persistent to UV-light photolysis.

关键词： β-Cyclodextrin Orange Ⅱ inclusion complex photostability

STUDY ON SHIFT SCHEDULE AND SIMULATION OF AUTOMATIC TRANSMISSION

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Chinese Journal of mechanical engineering 2001年第3期14卷 250-253页

作者： Gong Jie,Zhao Dingxuan (college of mechanical Science and engineering ,Jilin{3.) 吉林大学机械科学与工程学院吉林长春

From the point of view of saving energy, a new shift schedule and auto-controlling strategy for automatic transmission are proposed. In order to verify this shift schedule, a simulation program using a software package of Matlab/ Simulink is developed. The simulation results show the shift schedule is correct. This shift schedule has enriched the theory of vehicle automatic maneuvering and will improve the efficiency of hydrodynanic drive system of the vehicle.

关键词： engineering vehicle Automatic transmission Shift schedule Simulation Saving energy

The Application of Laser Processing on Clutch Manufacture

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武汉理工大学学报 2006年第S3期28卷 936-939页

作者： ZHU Qigen School of mechanical and Electronic engineering,wuhan{3. of technology,wuhan 43.070,China, School of mechanical and Electronic engineering Wuhan University of TechnologyWuhan 430070China

The first multi-function laser processing system in the domestic for clutch manufacture,with abilities of cutting, jointing and heat treatment,was reported in this *** external optical path,double laser heads,adjust device by manual operation,automatically track were employed in this system Also the other parts of vehicles can be fabricated by this system,as well as *** special processing to manufacture the clutches of heavy vehicles,which was developed by the project of this laser processing system,achieved the international standards and satisfied the economic development and nation defense in the do- mestic.

关键词： The Application of Laser Processing on Clutch Manufacture

ARCHITECTURE OF MANUFACTURING EXECUTION SYSTEM IN THE EXTENDED ENTERPRISE

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Chinese Journal of mechanical engineering 2002年第1期15卷 90-93页

作者： Song Haisheng college of Electronic and mechanical engineering， Hebei{3. of Science and technology，Shijiazhuang 050054，China Wang Jiahai Zhang Shu Tongji{3. college of Electronic and mechanical engineering Hebei University of Science and Technology Shijiazhuang 050054 Tongji university

The extended enterprise is formed according to the philosophy of dispersednetworked manufacturing. Manufacturing execution system (MES) can close the information gap whichexists between device control system and production information management system. The functions andthe web-based architecture of the MES in the extended enterprise are introduced. Using thecooperating system models of object-oriented and distributed agents and CORBA, all objects keep touniform interface standards and are easily inserted to object request broker. The utilization ofdistributed MES in extended enterprise can adapt fast change of manufacturing environment andresource. It also can improve the independent management capability of manufacturing cell and theenterprise response capability to global economic competition.

关键词： Extended enterprise Manufacturing execution system Dispersed networkedmanufacturing Agent