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HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2, YE Sheng-ping2, YIN Wei-xin3. XUE Qiong4 (1. School of Mechanical engineering and Automation, wuhan Textile University, wuhan 43.073. {3., china 2. State Key Laboratory of Material Processing and Die and Mould technology, Huazhong University of Science and technology, wuhan 43.074, {3., china 3. wuhan Zhike Abrasive-Resistant Material Science and technology Development Co Ltd, wuhan 43.073. {3., china 4. college of Science, wuhan University of technology, wuhan 43.079, {3., china) [a] School of Mechanical engineering and Automation Wuhan Textile University Wuhan 430073 Hubei China [b] State Key Laboratory of Material Processing and Die and Mould technology Huazhong University of Science and Technology Wuhan 430074 Hubei China [c] wuhan Zhike Abrasive-Resistant Material Science and {2. Development Co Ltd Wuhan 430073 Hubei China [d] college of Science Wuhan University of Technology Wuhan 430079 Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan University Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. Department of Chemical engineering, {2. University of technology, {2. 43.070, hubei, china 2. college of Chemistry and Molecular Sciences, {2. University, {2. 43.072. hubei, china wuhan University of technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan University College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 3.°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 3.%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

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

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Journal of wuhan University of {2.(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 & {2. 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

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 University of Science and {2., wuhan 43.074,{3. 2. college of Transportation, wuhan University of {2., wuhan 43.063.{3. 3. Department of Mathematics and Physics, Anhui University of Science and {2., Huainan 2.0}001,{3.) 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

Effect of Addition of Sodium Dodecyl Sulfite on Physical Properties of Wheat Gluten Films

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Journal of wuhan University of {2.(Materials Science) 2005年第2期20卷 15-19页

作者：曾瑜薇 School of Foreign Language Hubei University of TechnologyWuhan 430068China Assoc.Prof

Films were made from the wheat glutens treated with 5%,10%,15%,2.%,2.% and 3.%(wt% of gluten) of sodium dodecyl sulfite (SDS) in order to improve the properties of the films. Glycerol was used as a *** addition of SDS in wheat glutens prior to forming films significantly increased the elongation at break(E) (P2. and P_(CO_2. of films from gluten treated with SDS was noticed. although SDS-treated gluten film was slightly more yellow and darker than control one, it was not visually detrimental. It is indicated that the treatment with SDS prior to forming films greatly enhances the mechanical properties of wheat gluten *** obivous improvement in water vapor permeability and extensibility of gluten films means that the use of SDS is a potential choice for improving properties of gluten films. The edible film was used to preserve tomatoes. The experimental results show that the shelf life of tomatoes coated with the edible film is extended, and the nutritional quality is kept well.

关键词： wheat gluten sodium dodecyl sulfite (SDS) tensile strength (TS) elongation at break(E) water vapor permeability(WVP) tomato preservation

11-Round Impossible Differential algebraic Attack for Serpent Encryption algorithm

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wuhan University Journal of Natural Sciences 2010年第3期15卷 232-236页

作者： HU Zhihua1,2. QIN Zhongping3.1. School of Computer, wuhan University, wuhan 43.072. hubei,{3. 2. college of Mathematical and Information Sciences,Huanggang Normal University, Huanggang 43.000, hubei,{3. 3. School of Software engineering, Huazhong University of Science and technology, wuhan 43.074, hubei,{3. School of Computer Wuhan University Wuhan Hubei China college of Mathematical and Information Sciences Huanggang Normal University Huanggang Hubei China School of Software engineering Huazhong University of Science and Technology Wuhan Hubei China

This paper explored algebraic features of nonlinear parts in Serpent encryption algorithm and offered an 11-round Serpent-{2.8 impossible differential algebraic attack through utilizing the method in constructing S-box algebraic equations. The new method analyzed block ll-round Serpent with 2.2.7 selected plaintexts and 2.2. bytes memory space at the same time of giving a new design principle of S-box anti-algebraic attack.

关键词： impossible differential Serpent algebraic equation

Minimum Exact Cover Problem of Group Key Distribution

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wuhan University Journal of Natural Sciences 2009年第2期14卷 137-142页

作者： FU Xiong1,2. XU Shouzhi3.1. School of Law ,wuhan University, wuhan 43.072. hubei,{3. 2. Department of technology, Guangzhou Luogang District People’s Court, Guangzhou 51073., Guangdong,{3. 3. college of Electronic engineering and Information technology,{3. Three Gorges University, Yichang 443.02. hubei,{3. School of Law Wuhan University Wuhan 430072 Hubei China Department of technology Guangzhou Luogang District People’s Court Guangzhou 510730 Guangdong China college of Electronic engineering and Information {2. China Three Gorges University Yichang 443002 Hubei China

Secure group communications are restrained by the number of the group size, number of changes and their distribution, all existing works do not meet the commands of applications with large group size and high dynamic members. In this paper, minimum exact cover problem for group key distribution （GMECP） is presented, and a heuristic solution is testified. Then an algorithm of batch rekeying with renewing cost tending to zero is illustrated, which can process any large number of change requests with best security guaranteed. Efficiency analysis and simulation test show that the achievement can improve the efficiency of any tree-based group key management.

关键词： minimum exact cover problem group key distribution secure multicast group key management

Sensitive Determination of DNA by RLS Enhancement of Metal Ions

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wuhan University Journal of Natural Sciences 2004年第2期9卷 234-238页

作者： Huang Jian-ping 1,2. Chen Fang 1, Ai Xin-ping 1, He Zhi-ke 1 1. college of Chemistry and Molecular Sciences, wuhan University, wuhan 43.072. {3., china 2. Department of Environmental engineering, {3. Agricultural college, Jingzhou 43.02., {3., china wuhan University College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) hubei Agricultural {2. Department of Environmental Engineering Jingzhou Hubei China (GRID:grid.49470.3e) wuhan University College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The interactions between metal ions and DNA have been studied by the resonance light scattering (RLS) spectra. In the acidic condition, the RLS signals of metal ions, especially the transition metal ions in group IB and IIB, were increased by DNA. And it is found that the enhancement of RLS signals is linear to the concentration of DNA, so the RLS method for DNA determination was proposed in the presence of Cu2.. On the optimum conditions, the linear range and the detect limit of ctDNA is 4×10?8–4×10?6 g· mL?1 and 1. 13.10?8 g·mL?1, respectively. The proposed method is successfully applied to determine the extracted plasmid DNA ofBacillus subtilis DB104. Key words resonance light scattering - DNA - metal ions CLC number O 657.3.Foundation item: Supported by National Natural Science Foundation of china (2.2.502.) and the National Key Basic Research and Development Program (973.Program 2.02.B2.1800).Biography: Huang Jian-ping(1964-), male, Associate professor, research direction: bioanalysis.

关键词： resonance light scattering DNA metal ions

Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2

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Journal of wuhan University of {2.(Materials Science) 2009年第1期24卷 95-99页

作者：张高文 college of Chemistry and Environment Hubei University of Technology

Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2.for direct methanol fuel cell （DMFC） application were prepared with sulfonated polyether ether ketone（SPEEK） and tetracethoxy silane（TEOS） by sol-gel method. The covalent crosslinking structure was formed between —SO3. of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2.is improved obviously and SiO2.disperses uniformly in the polymer matrix and the particle diameter of SiO2.does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3. and SiO2..

关键词： direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability