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Surface Nanocrystallization of Magnesium Alloy AZ91D by High-Energy Shot Peening

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Journal of Wuhan university of Technology(Materials Science) 2009年第4期24卷 515-519页

作者：张津 school of Materials Science & Engineering University of Science and Technology Beijing College of Materials Science & Engineering Chongqing University of Technology

High-energy shot peening （HESP）, a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESP and heat treatment at different temperatures were investigated. The mi- crostructure evolution was conducted using X-ray diffraction （XRD） and field emission scanning electronic microscopy （FESEM）. The hardness was measured by microhardness tester. The experimental results show that surface nanocrystrallization of AZ91D obtained by HESP would lead to the increase of microhardness. Low temperature heated at 100℃ for 1 h do not change the property obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400℃ for 1 h.

关键词： AZ91 D surface nanocrystallization HESP microhardnss corrosion resistance

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2. WANG Xiaofeng1, CAO Maosheng3. and LIANG Ji1(1. Department of Mechanical Engineering, Tsinghua university, Beijing 100084, China 2. Center for Analysis and Measurement, Harbin Institute of Technology, Harbin 150001, China 3. school of Material Science and Engineering, Tsinghua university, Beijing 100084, China) Department of Mechanical Engineering Tsinghua University Beijing 100084 China Center for Analysis and Measurement Harbin Institute of Technology Harbin 150001 China school of Material Science and Engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Structures and stability of isomers of[C,N,N,P]system

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Science China Chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2. ZHONG Hua1, YU Haitao1, FU Honggang1,3.& SUN Jiazhong1,3.1. {2. of Chemistry and Materials Science, Heilongjiang university, Harbin 150080, China 2. {2. of Chemistry and Chemical Engineering, Qiqihar university, Qiqihar 161006, China 3. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 13.02.0} China 1. school of Chemistry and Materials Science Heilongjiang University 150080 Harbin China 2. school of Chemistry and Chemical Engineering Qiqihar University 161006 Qiqihar China 3. Jilin university State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry 130023 Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3.YP/6-3.1G(d) and QCISD(t)/6-3.1+G(2.f) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2.′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

Localization of genes for lateral branch and female sex expression and construction of a molecular linkage map in cucumber (Cucumis sativus L.) with RAPD markers

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Progress in Natural Science:Materials International 2005年第2期15卷 48-53页

作者： LI Xiaozun1*, PAN Junsong1*, WANG Gang1, TIAN Libo3. SI Longting3. WU Aizhong2.* and CAI Run1**(1. Agriculture and Biology {2., Shanghai Jiaotong university, Shanghai 2.1101, China 2. Shanghai Academy of Agricultural Science, Shanghai 2.1106, China 3. Horticulture {2., Shenyang Agricultural university, Shenyang 110161, China) Agriculture and Biology school Shanghai Jiaotong University Shanghai 201101 China. Horticulture school Shenyang Agricultural University Shenyang 110161 China. Shanghai Academy of Agricultural Science Shanghai 201106 China

A cucumber (Cucumis sativus L.) molecular linkage map, including 79 random-amplified polymorphic DNAs (RAPD) and two genes , lb for lateral branch and f for female sex expression, is constructed from a cross between a line, S52. with weak lateral growing ability and staminate from Dabieshan Mountains area in China and another line, S06, with strong lateral growing ability and gynoecious from Europe. The map contains nine linkage groups and spans 1110.0 cM with an average distance of 13.7 cM between loci. The lb locus is located in a longer linkage group LG-2.and flanked by two markers, OP-Q5-1 and OP-M-2.2. at 9.3.cM and 15.9 cM, respectively. In the meantime, the RAPD loci, OP-Q5-2.and BC151, in a short linkage group were found to flank f at 13.7 cM and 13.4 cM, respectively. The construction of RAPD map has paved a way for further study of the genes for lateral branch, female sex expression and other agronomic traits in cucumber.

关键词： cucumber (Cucumis sativus L.) lateral branch gynoecy RAPD genetic mapping

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2. YANG Feng3. XIAO Hui1, RAO Li-min1 (1. school of Nuclear Engineering and Technology, East China Institute of Technology, Fuzhou 3.4000, Jiangxi, China 2. school of Mechanical Engineering and Automation, Northeastern {2., Shenyang 110004, {3., China 3. school of Civil and Environmental Engineering, East China Institute of Technology, Fuzhou 3.4000, Jiangxi, China) [a] school of Nuclear Engineering and Technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] school of Mechanical Engineering and Automation Northeastern University Shenyang 110004 Liaoning China [c] school of Civil and Environmental Engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

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Science China(Life Sciences) 2006年第2期49卷 115-122页

作者： ZHAO Hongxin1,2.3. XIE Baoen2.& CHEN Sanfeng1,2.1. State Key Laboratory for Agrobiotechnology and Biological school, China Agricultural {2., Beijing 100094, China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, China Agricultural {2., Beijing 100094, China 3. Chemical and Biological school, ShenYang Normal {2., Shenyang 11003., China 1. State Key Laboratory for Agrobiotechnology and Biological school China Agricultural University Beijing 100094 China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry China Agricultural University Beijing 100094 China 3. Chemical and Biological school ShenYang Normal University Shenyang 110034 China

A 3.4 bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG; then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 102.4 bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54]-dependent promoter sequence was detected upstream of the nifB gene; nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4 [+]; O2.showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.

Research and application of flood damage evaluation information system

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中国有色金属学会会刊：英文版 2005年第S1期15卷 204-207页

作者： SHI Jin-feng~1, WU Zhi-zhou~2. SONG Wei-dong~1 (1. liaoning technical university, fuxin 12.000, China 2. Tongji {2., Shanghai 2.0092. China) liaoning Tech Univ Fuxing 123000 Peoples R China Tongji Univ Shanghai 200092 Peoples R China

The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of flood areas were accomplished in RS image processing software, ENVI, the flood damages information system, digital terrain model and flood damages evaluation information system were developed on GIS platform GeoMedia. The problem of the combination of multi-source data was addressed, furthermore, the problems of how to build the flood damages evaluation model and the inundating elevation model were deeply probed, the calculating formulas were also given. Case study result shows that the evaluation models are correct and data are reliable, we can use it to evaluate real-time flood damages and provide evidences for decision-making of leaders, moreover, it is of great instructive significance to the research of flood damages evaluation theories.

关键词： flood damages GIS remote sensing digital terrain model evaluation

Phase transition in the Zr_(60)Al_(15)Ni_(2.) bulk metallic glass subjected to rolling at room temperature

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Science China(Technological Sciences) 2006年第6期49卷 655-662页

作者： YAN Zhijie1, 2. LI Jinfu1, ZHOU Yaohe1 & WU Yanqing3.1. State Key Laboratory of Metal Matrix Composites, school of Materials Science and Engineering, Shanghai Jiao Tong {2., Shanghai 2.003., China 2. school of Materials Science and Engineering, Taiyuan {2. of Science and Technology, Taiyuan 03.02., China 3. school of Environmental Science and Engineering, Shanghai Jiao Tong {2., Shanghai 2.003., China State Key Laboratory of Metal Matrix Composites School of Materials Science Engineering Shanghai Jiao Tong University Shanghai 200030 China school of Materials Science Engineering Taiyuan University of Science Technology Taiyuan 030024 China school of Environmental Science Engineering Shanghai Jiao Tong University Shanghai 200030 China

The microstructure evolution of the Zr60Al15Ni2. metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC); high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns; exothermic enthalpy ΔH of DSC plots do not monotonically change with the variation of deformation degrees . As is not large than 2.%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 3.%, the values of FWHM; ΔH become larger than that of the as-cast state, while their values begin to decrease again as reaches about 85%. These results indicate that the reversible transitions between ordered; disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering; shear-induced disordering during rolling.

关键词： metallic glasses, plastic deformation, phase transformations, shear bands.

Geochemical characteristics of pyrolysis gas from epimetamorphic rocks in the northern basement of Songliao Basin,Northeast China

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Science China Earth Sciences 2008年第S1期51卷 140-147页

作者： YANG Chun 1 ,LUO Xia 2.,LI Jian 2.,LI ZhiSheng 2.,LIU QuanYou 3.&Wang YuLin 4 1 Department of Earth Sciences,Zhejiang university,Hangzhou 3.002.,China 2.Research Institute of Petroleum Exploration and Development(Langfang Branch),Langfang 065007,China 3.Research Institute of Petroleum Exploration and Development,Beijing 100083.China 4 Department of Source and Environment,liaoning {2. university,fuxin 12.000,China Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China Res Inst Petr Explorat & Dev Langfang Branch Langfang 065007 Peoples R China Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China liaoning Tech Univ Dept Source & Environm Fuxing 123000 Peoples R China

The Xushen gas field,located in the north of Songliao Basin,is a potential giant gas area for China in the *** proved reserves have exceeded 1000×10 8 m 3.by the end of ***,the origin of natural gases from the deep strata is still in *** rocks as a potential gas source are widely spreading in the northern basement of Songliao *** to pyrolysis experiments for these rocks in the semi-confined system,gas production and geochemistry of alkane gases are discussed in this *** Carboniferous-Permian epimetamorphic rocks were heated from 3.0℃to 550℃,with temperature interval of 50℃.The gas production was quantified and measured for chemical and carbon isotopic *** show thatδ13. 1 is less than?2.‰,carbon isotope trend of alkane gas isδ13. 1 3. 2.3. 3.orδ13. 1 3. 2.>δ13. 3.,these features suggest that the gas would be coal-type gas at high-over maturity,not be inorganic gas with reversal trend of gaseous alkanes (δ13. 1 >δ13. 2.>δ13. 3.).These characteristics of carbon isotopes are similar with the natural gas from the basin basement,but disagree with gas from the Xingcheng ***,the mixing gases from the pyrolysis gas with coal-typed gases at high-over maturity or oil-typed gases do not cause the reversal trend of carbon *** gas generation intensity for epimetamorphic rocks is 3.0×10 8 ―2.0}8×10 8 m 3./km 2.,corresponding to Ro from 2.0%to 3.5%for organic matter.

关键词： Northern Songliao Basin epimetamorphic rock pyrolysis experiment gas generation potential carbon isotope