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Algorithm of graph isomorphism with threedimensional DNA graph structures

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Progress in Natural science:materials International 2005年第2期15卷 86-89页

作者： LIU Guangwu 1,2*, YIN Zhixiang 1,3. XU Jin1 and DONG Yafei1(1. department of Control science and engineering, Hua Zhong {3. of science and technology, Wuhan 43.074, China 2. College of Transportation, Wuhan {3. of technology, Wuhan 43.063. China 3. department of Mathematics and Physics, anhui university of science and technology, huainan 23.001, China) department of Control science and engineering Hua Zhong University of Science and Technology Wuhan 430074 China. College of Transportation Wuhan University of Technology Wuhan 430063 China. department of Mathematics and Physics Anhui University of Science and Technology Huainan 232001 China

An algorithm for solving the graph isomorphism problem with 3.D DNA structures is proposed in this paper. The k-armed branched junction molecules are used to code k-degree vertices. Double stranded molecules are used to code edges. Then the molecules are mixed in a tube to be ligated. The result can be detected by gel electrophoresis. The time complexity of the algorithm is O(n2), where n is the number of vertices of the graph.

关键词： DNA computing DNA graph structure graph isomorphism

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

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Journal of Wuhan university of technology(materials {3.) 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

Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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science China(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2 1 department of materials science and {3.,Nanjing university of science and technology,Nanjing 210094,China 2 College of materials science and {3.,Southeast university,Nanjing 211189,China 1. department of materials science and {3. Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Effect of Fe metal on the growth of silicon oxide nanowires

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International Journal of Minerals,Metallurgy and materials 2009年第3期16卷 317-321页

作者： Wei-long Liu1), Shu-huei Hsieh1), Ching He Chen2), and Wen-jauh Chen3. 1) department of materials science and {3., Formosa university, Yunlin 63., China Taipei 2) department of materials {3., Pingtung university of science and technology, Pingtung 912, China Taipei 3. Graduate School of materials science, Yunlin university of science and technology, Yunlin 63., China Taipei [a]department of materials science and {3. Formosa University Yunlin 632 China Taipei [b]Department of Materials Engineering Pingtung University of Science and Technology Pingtung 912 China Taipei [c]Graduate School of Materials Science Yunlin University of Science and Technology Yunlin 632 China Taipei

Silicon oxide (SiOx) nanowires are generally grown on Si substrate under the catalysis of Au in N2 atmosphere at elevated temperatures. Because the price of Au metal is quite high, Fe metal is then used to replace a part of Au for catalyzing the growth of SiOx nanowires. The results show that the Fe film can be used as the diffusion barrier of Au. SiOx nanowires are grown on Au/Fe/Si substrate at 103.°C. Under the catalysis of Fe/Au, the efficiency for the growth of SiOx nanowires is promoted.

关键词： silicon oxide nanowires Au catalyst Fe substitution Si substrate

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science China(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3. FENG ChengMing1 1 Mechanical and Electronic engineering College, Shandong Agricultural university, Tai’an 271018, China 2 College of materials {3. and engineering, university of {3. and technology, Beijing 100083. China 3.College of Material {3. and engineering, Beijing university of Chemical technology, Beijing 100029, China Mechanical Electronic engineering College Shandong Agricultural University Tai’an 271018 China College of materials science engineering University of Science technology Beijing 100083 China College of Material science engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

STUDY ON PROPERTIES OF RECLAIMED SODIUM SILICATE SAND

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Chinese Journal of Mechanical engineering 1998年第3期11卷 49-53页

作者： Zhao Guoping Jiang Zongyu department of materials engineering, Jiangsu {3. of science and technology Jiangsu Univ of science and Technology Jiangsu China

SEM shows that flowers and plants like sodium carbonate exists on the surface of sodium silicate sand grains when hardened by carbon dioxide, baculiform sodium acetate exists not only on sand surface but also inside sodium silicate film when hardened by ester method. The strength of sodium silicate sand mainly depends on the point bridge connecting strength of dewatered sodium silicate film. The performance of reclaimed sodium silicate sand is determined by the extent of which salinous crystal is eliminated and reasonableness of relevant technological methods.

关键词： Sodium silicate sand Structure Reclamation

Chemical Extraction Preparation of Delithiated Cathode materials of Li-ion Battery

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Journal of Wuhan university of technology(materials {3.) 2009年第6期24卷 863-866页

作者：闫时建 School of materials science and engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Interfacial Microstructure and Properties of Ti(C, N)/Ni Bonded by Transient Liquid-phase Diffusion

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Journal of Wuhan university of technology(materials {3.) 2009年第3期24卷 432-439页

作者：周世权熊惟皓 School of Mechanical science and engineering Huazhong University of Science and Technology department of Mechanical engineering University of Waterloo School of materials science and engineering Huazhong University of Science and Technology

Effects of the main process parameters（temperature and time） on microstructure and properties of Ti（C, N）/Ni interface bonded by （Cu＋Nb） interlayer in a vacuum diffusion bonding device were investigated. The interfacial microstructures consisted initially of Ni3.b metallic compound and eutectic of Ni3.b ＋ CuNiss, and finally transformed to （Ti, Nb）（C, N）＋Ni3.b near Ti （C, N） and NiCuss ＋ Ni3.b near Ni when diffusion bonding temperature was 1 523.1 573.K. It was clear that Cu was a constituent in the transient liquid phase （TLP） into which Ni was dissolved by forming Cu-Ni transition liquid. Nb was dissolved in Cu-Ni transition liquid rapidly. Ti （C, N） conld be wetted by resultant Ni-Nb-Cu transient liquid phase which was followed by a little （Ti, Nb）（C, N） solid solution formed at interface. This increased the interface combining capability. Ultimately the interface shear strength was able to reach 140 MPa. The theoretle analysis and experimental results show that the growth of interfacial reaction layer Ni3.b accords with parabola law, and the activation energy of diffusion reaction is 115.0±0.5 kJ/mol, while the diffusion reaction speed constant is 12.53.mm/s^1/2.

关键词： vacuum diffusion bonding transient liquid phase (TLP) diffusion bonding interlayer activation energy

ORDER STATE AND STABILITY OF MARTENSITE IN AN AIR-QUENCHED Cu-Zn-Al ALLOY

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中国有色金属学会会刊：英文版 1996年第3期6卷 113-118页

作者： Wang Mingpu Jin Zhanpeng Yin Zhimin Xu Genyin(department of materials science and {3.,Central South university of technology, Changsha 410083.anhui Institute of technology, Hefei 23.069) CENT S UNIV TECHNOL DEPT MAT SCI & ENGNCHANGSHA 410083PEOPLES R CHINA anhui INST TECHNOL HEFEI 230069PEOPLES R CHINA

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关键词： shape memory alloy Cu-Zn-Al alloy martensite ordering stabilization