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Creep Characteristics of Crumb Rubber Modified Asphalt Binder

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Journal of Wuhan university of Technology(Materials Science) 2011年第1期26卷 118-120页

作者：王岚 College of Civil engineering Inner Mongolia University of Technology

Crumb rubber modified asphalt containing 2. percent crumb rubber particles of 30 mesh has been examined by Scanning Electron Microscope （SEM） to observe the microcosmic appearance and the characteristic distribution of crumb rubber particles in asphalt. The SEM pictures reveal that the crumb rubber particles distribute evenly in the asphalt and they are compatible well with asphalt. The shear creep test of crumb rubber modified asphalt was carried out at -1. ℃ and 40 ℃ by Dynamic Shear Rheology （DSR）. The shearing deformation at different temperature and creep stiffness modulus curve at loading stage of crumb rubber modified asphalt have been measured. The stiffness modulus of crumb rubber modified asphalt is much temperature sensitive and it decays much quick at the early stage of loading than normal asphalt. The rate of decay of stiffness modulus is slow at the subsequent stage and stiffness modulus approaches to a stable value at the final stage at a higher temperature. In addition, Burgers model is suitable to describe and simulate experimental results of viscoelastic properties of the crumb rubber modified asphalt.

关键词： crumb rubber modified asphalt creep stiffness modulus rheology model model parameter

Preparation of Reactive Powder Concrete Using Fly Ash and Steel Slag Powder

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 349-354页

作者：彭艳周 College of Hydraulic & Enviormental engineering China Three Gorges University Key Laboratory for Silicate Materials Science and engineering of Ministry of Education Wuhan University of Technology

To decrease the cement and SF content of RPC by using ultra-fine fly ash （UFFA） and steel slag powder （SS）, the effect of these mineral admixtures on compressive strength of RPC were investigated. The experimental results indicate that the utilization of UFFA and SS in RPC is feasible and has prominent mechanical performance. The microstructure analysis （SEM and TG-DTG-DSC） demonstrated that the excellent mechanical properties of RPC containing SS and UFFA were mainly attributed to the sequential hydration filling effect of the compound system.

关键词： ultra-fine fly ash steel slag powder reactive powder concrete sequential hydration microstructure strength

Controlled free radical polymerization of styrene initiated from the alkoxyamine-functionalized silicon surface

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Science china Chemistry 2005年第5期48卷 449-458页

作者： CHEN Zhijun1. ZHOU Sikai1. LU Wenzhong1. FANG Shaoming1. JIANG Xiqun2.& YANG Changzheng2.1. College of Materials and Chemical engineering, Zhengzhou university of Light Industry, Zhengzhou 450002.{2. 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & engineering, College of Chemistry & Chemical engineering, Nanjing university, Nanjing 2.0093,{2. 1. College of Materials and Chemical engineering Zhengzhou University of Light Industry 450002 Zhengzhou China 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & {1. College of Chemistry & Chemical Engineering Nanjing University 210093 Nanjing China

We describe a new method of fabricating a brush-like polystyrene layer anchored on the surface of the silicon substrate, which involves three steps, namely (i) the attachment of 3-methacryloxypropyltrimethoxysilane onto the silicon surface; (ii) the reaction of vinyl moiety at another extremity of the anchored 3-methacryloxypropyltrimethoxysilane to 4-Hydroxyl-2. 2. 6, 6-tetramethyl-1.piperidinyloxy (HTEMPO?) catalyzed by azobisisobutyronitrile (AIBN); (iii) living free radical grafting polymerization of styrene in the presence of HTEMPO?. The controllable living free radical polymerization permits accurate control of both the molecular weight and the polydispersity. X-photoelectron spectroscopy measurement proved that the alkoxyamine initiator layer forms on the silicon surface. XPS and Ellipsometry measurements showed that the poly-styrene chains were covalently anchored onto the silicon surface. The thickness of the grafted polymer layer can be accurately manipulated by altering the polymerization time. The new method allows synthesizing random copolymer and block copolymers by the sequential growth of monomers from the substrate surface.

关键词： polymer brush, controlled living free radical polymerization, thickness, atomic force microscopy, 3-methacryloxypropyltrimethoxysilane.

Droplet creator based on electrowetting-on-dielectric for lab on a chip

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Science china(Technological Sciences) 2006年第2期49卷 248-256页

作者： ZENG Xuefeng1. YUE Ruifeng1. WU Jiangang1. HU Huan1. DONG Liang1. WANG Zheyao1. HE Feng2.& LIU Litian1.1. Institute of Microelectronics, Tsinghua {1., Beijing 1.0084, china 2. Department of {2. Mechanics, Tsinghua {1., Beijing 1.0084, china 1. Institute of Microelectronics Tsinghua University Beijing 100084 China 2. Department of {1. Mechanics Tsinghua University Beijing 100084 China

Electrowetting-on-dielectric (EWOD) is to directly control the wettability of liquids on the solid surface by applying the electric potential to the microelectrode array under the dielectric layer. The prototype of the EWOD droplet creator with the sandwiched structure is used: the droplet is sandwiched between the top and bottom plates; the bot- tom plate consists of silicon used as the substrate of the microelectrode array, nitride sili- con film deposited by low pressure chemical vapor deposition as the dielectric layer and the fluorocarbon polymer film deposited by inductively coupled plasma chemical vapor deposition as the hydrophobic layer; and the top plate is the transparent electrode covered with the hydrophobic layer. To obtain the required minimum voltage, the process and the criterion of creating droplets are analyzed. At the voltage of 35 V the deionized water droplet surrounded in silicone oil is successfully created.

关键词： micro total analysis system, electrowetting-on-dielectric, creation and control of droplets, inductively coupled plasma chemical vapor deposition.

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

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Science china Chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1. YU Haitao1. LI Mingxia1. FU Honggang1.2.& SUN Jiazhong1.2.1. College of Chemistry and Chemical engineering, Heilongjiang university, Harbin 1.0080,{2. 2. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 1.002.,{2. 1. College of Chemistry and Chemical engineering Heilongjiang University 150080 Harbin China 2. State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University 130023 Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-31.G(d) and QCISD(t)/6-31.+G(2.f)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1. 2.'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1.from fragments SiN(2.) and PN (1.), which have been well characterized in space, and thus, isomer E1.can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2.) + PN(1.)→ E1.and the standard enthalpy of formation of isomer E1.are 2.5.2. and 457.99 kJ/mol, respectively, at 2.8.1. K. Keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

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

Muddy water seepage theory and its application

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Science china(Technological Sciences) 2006年第4期49卷 476-484页

作者： DANG Faning1. LIU Yunhe1. CHEN Junqiang1. ZHENG Zhongan2.& WANG Zhouyu2.1. Institute of Water Resources and Hydro-electric engineering, Xi’an university of Technology, Xi’an 71.048,{2. 2. City Water Matter Bureau, Shizuishan 753000,{2. 1. Institute of Water Resources and Hydro-electric engineering Xi’an University of Technology Xi’an 710048 China 2. City Water Matter Bureau Shizuishan 753000 China

On condition that the seepage coefficients of sediment and stratum are nar- rowly or widely different, seepage stratum is homogeneous or layer. The muddy water seepage integral and differential equations based on Darcy’s law are established, and then their difference formula of the differential equations are derived. The method pre- sented was used in the deep recharge test in Shizuishan, where power plant cooling tail- ing water was used to recharge and mine deep underground water. This is firstly used in china. The law of sediment accumulation on the earth surface, and the rule of infiltration capacity changing with time are studied. The pattern of water table changing with time affected by the recharge irrigation is predicted.

关键词： seepage, sediment accumulation, seepage coefficient, muddy water seepage differential equation.

Effects of Cu^(2.) on characteristic of SV currents

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Science china Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1.2.& YANG Pin1.1. Key Laboratory of Chemical Biology and Molecular {1. of Ministry of Education, Institute of Molecular Science, Shanxi university, Taiyuan 030006,{2. 2. Institute of Environment Science, Taiyuan university of Science and Technology, Taiyuan 03002.,{2. 1. Key Laboratory of Chemical Biology and Molecular engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China 2. Institute of Environment Science Taiyuan University of Science and Technology Taiyuan 030024 China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2. on Slow Vacuolar (SV) current’s characteristic. Our results show that Cu2. in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2. significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2.. These results show that there may be some Cu2. binding sites on SV channels and binding to which can change SV current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2., SV channel.

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science china(Technological Sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1. QIAN Yingping1.3, WANG Guilan1.& ZHENG Qiguang2.1. School of Material Science and Technology, Huazhong {1. of Science and Technology, Wuhan 430074, china 2. Institute of Laser Technology and {2., Huazhong {1. of Science and Technology, Wuhan 430074, china 3. Mechanical {2. College, Hubei {1. of Technology, Wuhan 430068, china 1. School of Material Science and Technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical engineering College Hubei University of Technology Wuhan 430068 China 2. Institute of Laser Technology and {1. Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Dissolution theory of gold in alkaline thiourea solution(Ⅲ) ——Thermodynamics on dissolution of gold in alkaline thiourea solution containing Na _2.O_3

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中国有色金属学会会刊：英文版 1999年第3期9卷 646-650页

作者： Chai Liyuan(柴立元) 1. Masazumi Okido 2.1. Department of Nonferrous Metallurgy, Central South {1. of Technology, Changsha 41.083, P.R.china 2. Center for Integrated Research of Science and {2., Nagoya {1.,Nagoya 464, Japan 中南工业大学有色冶金系湖南长沙 Nagoya university 日本

The oxidants of gold were investigated in an alkaline thiourea solution containing Na 2.O 3, in which Na 2. 2. 8 is a proper oxidant for dissolving gold because of in such homogeneous sulfur system coexisting complex agent, oxidant and stabilizing agent. The thermodynamic analyses were conducted on the dissolving of gold in the alkaline thiourea solution containing Na 2.O 3 by the oxidants oxygen or Na 2. 2. 8. The results show that the possibility of gold dissolution reduces with increasing pH value, while oxygen acts as oxidant; and when Na 2. 2. 8 acts as the oxidant of gold in the alkaline thiourea solution of pH 1.0}5, decomposition potential of thiourea decreases from the standard value 0.42.V to -0.32.V, also the dissolution trend of gold enhances with shifting the mix potential of the solution to the positive direction.

关键词： thermodynamic analysis gold dissolution thiourea leaching Document code:A