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Progress in Natural science:Materials International 2012年第5期22卷 426-432页

作者： Zhenxue shi,Jiarong Li,shizhong Liu science and technology on Advanced High Temperature structural Materials Laboratory,beijing Institute of Aeronautical Materials,beijing 100095,china science and technology on Advanced High Temperature structural Materials Laboratory Beijing Institute of Aeronautical Materials Beijing 100095 China

A nickel based single crystal superalloy with [001] orientation was prepared by the screw selecting method in the directionally solidified *** long term aging(LTA) of the alloy after full heat treatment was performed at 1040℃ for 200-800 *** microstructure and stress rupture properties at 980℃/250 MPa and 1070℃/140 MPa of the alloy long term aged(LTAed) for different time were *** coarsening γ’ phase and the broadening g matrix channel are observed in the samples LTAed at 1040℃,but the γ’ morphology is still in cubic shape after LTA for 800 *** TCP phase precipitates after LTA for 400 h,while needle shaped and granular TCP phase forms in dendritic core of the alloy after LTA for 600 *** increasing aging time,the volume of the TCP phase increases and it grows from the dendritic core to the interdendritic region along a fixed *** composition of the TCP phase is mainly composed of Re and *** increasing aging time the rupture life of the alloy at 980℃/250 MPa and 1070℃/140 MPa all turns ***,the relationship between the microstructure and the stress rupture properties is discussed.

关键词： single crystal superalloy Long term aging(LTA) Microstructure stress rupture properties

Effects of rafting on the meso deformation and fracture behaviour of a Ni-based single crystal superalloy at room temperature: In-situ observation and simulation

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science china(Technological sciences) 2024年第7期67卷 2133-2146页

作者： TAN Long YANG XiaoGuang shi DuoQi FAN Yongsheng shi Yi school of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China National Key Laboratory of science and technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 102206China school of Materials science&Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Microstructural rafting of Ni-based single-crystal(sC) superalloys is inevitable at elevated temperatures during long-term service with mechanical loading, which significantly affects the mechanical behaviour of the material. In this study, the effects of rafting on the mesodeformation and fracture behaviour of a Ni-based sC superalloy under cyclic and tensile loads were investigated using in situ scanning electron microscopy(sEM), digital image correlation(DIC), and crystal plasticity finite element method(CP-FEM) simulations. The results indicated that the tensile strength decreased significantly in the rafted specimens. In the cyclic tests, both the virgin and rafted specimens showed an increase in the maximum shear strain with cycle number. The interaction of cross-slip bands was captured by in situ sEM-DIC around the micro-notch of the virgin specimens during the tensile test, while a more homogeneous local deformation field was observed in the rafting specimens. In addition,the fracture behaviour was strongly influenced by the rafting morphology. The crack exhibited instantaneous and long-range fracture features along the octahedral plane as it propagated in the rafting specimen, whereas it deflected over a short distance between the crystallographic planes at an early stage in the virgin specimen, which is consistent with the CP-FEM ***, the CP-FEM results for the crack initiation direction on(111) dominant slip plane were consistent with the in situ sEM observations.

关键词： in-situ sEM-DIC Ni-based sC superalloys microstructural rafting deformation crack path CP-FEM

Photocatalytic Degradation of Rhodamine B Dye with High Purity Anatase Nano-TiO_2.synthesized by a Hydrothermal Method

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Journal of Wuhan university of technology(Materials science) 2011年第4期26卷 600-605页

作者：史晓亮 school of Mechanical and Electronic Engineering Wuhan University of Technology state Key Laboratory of Advanced technology for Materials synthesis & Processing Wuhan University of Technology

High purity anatase nano-TiO2 powders with high photocatalytic activity were prepared by a hydrothermal synthesis method. X-ray diffraction （XRD）, field emission transmission electron microscopy （FETEM）, ultraviolet-visible （UV-Vis） light absorption spectrum and photoluminescence （PL） spectrum were adopted to characterize the catalyst. Effects of temperature, time and sol concentration of hydrothermal synthesis on particle size and phases were investigated. Photocatalytic activities in the degradation of Rhodamine B Dye were studied. The experimental results indicated that photocatalytic activity of the nano-TiO2 powers was much higher than that of P25 （Degussa）.

关键词： TiO2 hydrothermal synthesis photocatalytic activity high purity anatase

PARALLEL LATTICE BGK sIMULATION OF NATURAL CONVECTION IN A CAVITY

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Journal of Hydrodynamics 2005年第5期17卷 564-570页

作者： shi Bao-chang LIU Hong-juan Parallel Computing Institute Huazhong University of Science and Technology Wuhan 430074 China Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China

A Coupled Lattice Bhatnagar Gross Krook （CLBGK） model was proposed with a robust boundary scheme to model the Bossinesq incompressible flows. The LBGK method is a powerful approach, but is also computationally demanding. Therefore, parallel computing was implemented, and the codes were run on the parallel computer “Lenovo DeepComp 1800” with 24 nodes written in C＋＋ using the Message Passing Interface （MPI） library. Numerical results for natural convection in a cavity with the Rayleigh number （ Ra ） ranging from 10^6 to 4× 10^10 were presented, and found to agree well with the previous work. And with the increase of the resolution rate, the accuracy has been greatly improved. In addition, new models were set up by applying different equilibriums to the CLBGK model to simulate the same problem, which all yield sound results.

关键词： Lattice Bhatnagar Gross-Krook ( LB( K )model, Lattice Boltzmann Method (LBM), natural convection, parallel computing, high resolution

Optical properties of the micro/nano structures of Morpho butterfly wing scales

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science china(Technological sciences) 2010年第1期53卷 175-181页

作者： LIAO GuangLan,ZUO HaiBo,CAO YanBo & shi TieLin state Key Laboratory of Digital Manufacturing Equipment and technology,Huazhong university of science and technology,Wuhan 430074,china 1. state Key Laboratory of Digital Manufacturing Equipment and technology Huazhong University of Science and Technology Wuhan 430074 China

The micro/nano structures of the wing scales in Morpho butterfly are responsible for the structural coloration,with a major part ascribed to interference and diffraction of *** optical properties of the butterfly wings were investigated by simulating a two-dimensional model using rigorous coupled-wave analysis *** is proved that they depend strongly on the structural parameters,incidence angle and refractive *** peak value and the peak wavelength of the reflection efficiency increase as the vertical periodic thickness *** peak value decreases observably,while both of the bandwidth and the peak wavelength increase when the number of the vertical periods *** of the horizontal periodic width causes a decrease of the peak value and an increase of the peak wavelength,although the variations are *** peak value decreases distinctly and the peak wavelength increases as the ambient refractive index increases,which corresponds to the variation in ambient *** research reveals the mechanisms of the brilliant structural color in Morpho butterfly,and is of great significance to the design,manufacture and applications of the bionic micro/nano structures for gas detection.

关键词： Morpho butterfly micro/nano structure rigorous coupled-wave analysis structural color

A simple lattice Boltzmann scheme for low Mach number reactive flows

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science china(Technological sciences) 2006年第6期49卷 714-726页

作者： CHEN sheng1,2, LIU Zhaohui2, ZHANG Chao2, HE Zhu2, TIAN Zhiwei2, shi Baochang 2 & ZHENG Chuguang2 1. technology Center of Wuhan Iron and steel (Group) Company, Wuhan 430080, china 2. state Key Laboratory of Coal Combustion, Hua Zhong university of science and technology, Wuhan 430074, china technology Center of Wuhan Iron steel [Group] Company Wuhan 430080 China state Key Laboratory of Coal Combustion Hua Zhong University of Science technology Wuhan 430074 China

For simulating low Mach number reactive flows, a simple and coupled lattice Boltzmann (CLB) scheme is proposed, by which the fluid density can bear significant changes. Different from the existing hybrid lattice Boltzmann (HLB) scheme and non-coupled lattice Boltzmann (NCLB) scheme, this scheme is strictly lattice Boltzmann style and the fluid density couples directly with the temperature. Because it has got rid of the constraint of traditional thought in lattice Boltzmann scheme,on the basis of the equality among the particle speed c, the time step △t and the lattice grid spacing △x held, both c and △t can be adjusted in this scheme according to a "characteristic temperature" instead of the local temperature. The whole algorithm becomes more stable and efficient besides inheriting the intrinsically outstanding strong points of conventional lattice Boltz-mann scheme. In this scheme, we also take into account different molecular weights of species, so it is more suitable for simulating actual low Mach number reactive flows than previous work. In this paper, we simulated a so-called "counter-flow" premixed propane-air flame, and the results got by our scheme are much better than that obtained by NCLB. And the more important thing is that the exploration in this work has offered a kind of brand-new train of thought for building other novel lattice Boltzmann scheme in the future.

关键词： lattice Boltzmann, low Mach number flows, reactive flows, simulation.

synthesis of Perfluorinated Oxetane and surface Properties of Its Cationic UV Cured Coating as a Reactive Additive

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Chemical Research in chinese Universities 2012年第3期28卷 550-554页

作者： ZHAN Fu,ZHANG Yong and shi Wen-fang * CAs Key Laboratory of soft Matter Chemistry,Department of Polymer science and Engineering,university of science and technology of china,Hefei 230026,P.R.china Univ sci & Technol china Dept Polymer Sci & Engn CAS Key Lab Soft Matter Chem Hefei 230026 Peoples R China

Perfluorinated oxetane(F-OXE) was synthesized via the ring-opening reaction of epoxy-functionalized oxetane with 2-(perfluorooctyl)ethanol under base-catalysis,and characterized by FTIR and 1 H NMR *** synthesized F-OXE was mixed with a commercial cationic UV curable resin,UVR6110,as a reactive additive at different mass fractions,and UV-irradiation cured in the presence of triphenylsulphonium hexafluoroantimonate as a cationic *** surface property study of cured films indicated that both hydrophobicity and oleophobicity were effectively enhanced by the addition of a small amount of *** contact angles of water and 1-bromonaphthalene on the surface of the cured film with 1.0%(mass fraction) F-OXE loading increased from 72 o to 106o and from 0o to 76o,respectively,compared with those on the surface of the film without F-OXE *** surface tension of UVR6110-F-OXE cured film decreased greatly from 55.6 mN/m of referenced film to 22.9 mN/*** results from X-ray photoelectron spectroscopy analysis confirm the migration and aggregation effect of perfluoroalkyl group to the surface of cured *** 1%(mass fraction) addition of F-OXE,the relative content of fluorine greatly increased from 0.70%(mass fraction) in the interior of the cured film to 36.73%(mass fraction) at the surface of the cured film,whereas those of carbon and oxygen decreased from 73.29% to 40.96% and from 26.00% to 22.30%,respectively.

关键词： Cationic UV curing Oxetane Perfluoroalkyl Water and oil repellence

Numerical simulation of profile control by clay particles after polymer flooding

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Petroleum science 2010年第4期7卷 509-514页

作者： Feng Qihong shi shubin Wang sen Zheng Lu school of Petroleum Engineering China University of Petroleum Qingdao Shandong 266555 China school of Petroleum Engineering China University of Petroleum Beijing 102249 China shengli Oil Production Research Institute SINOPEC Dongying Shandong 257000 China Bozhong Operation Company CNOOC Tianjin 300452 China

A three-dimensional,two-phase,five-component mathematical model has been developed to describe flow characteristics of clay particles and flocs in the profile control process,in which the clay particle suspension is injected into the formation to react with residual *** model considers the reaction of clay particles with residual polymer,apparent viscosity of the mixture,retention of clay particles and flocs,as well as the decline in porosity and permeability caused by the retention of clay particles and flocs.A finite difference method is used to discretize the equation for each component in the *** Runge-Kutta method is used to solve the polymer flow equation,and operator splitting algorithms are used to split the flow equation for clay particles into a hyperbolic equation for convection and a parabolic equation for diffusion,which effectively ensures excellent precision,high speed and good *** numerical simulation had been applied successfully in the 4-P1920 unit of the Lamadian Oilfield to forecast the blocking capacity of clay particle suspension and to optimize the injection parameters.

关键词： Clay particles flocs detention operator splitting algorithms numerical simulation

Geochemistry of Trace and Rare Earth Elements in Red soils from the Dongting Lake Area and Its Environmental significance

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Pedosphere 2009年第5期19卷 615-622页

作者： MAO Long-Jiang MO Duo-Wen YANG Jing-Hong shi Chen-Xi College of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 (China) College of Urban and Environmental sciences Peking University Beijing 100871 (China) Department of Earth sciences Nanjing University Nanjing 210093 (China)

Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of china were determined to understanding the provenance and weathering characteristics of the red *** results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess *** patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of *** element,especially the Rb/sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering *** Rb/sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake *** weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess *** in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.

关键词： Hunan Province provenance sedimentary processes weathering intensity

Effects of cooling rate on the microstructure and electrical properties of Dy_2O_3-doped ZnO-based varistor ceramics

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Rare Metals 2007年第1期26卷 39-44页

作者： LIU Hongyu KONG Hui JIANG Dongmei shi Wangzhou MA Xueming ZHANG Huining Department of Physics East China Normal University Shanghai 200062 China College of science Wuhan University of Science and Technology Wuhan 430081 China shanghai Research Institute of Petrochemical technology Shanghai 201208 China

The microstructure, electrical properties, and density of Dy2O3-doped ZnO-based varistor ceramics, prepared using high-energy ball milling （HEBM） and sintered at 800℃, were investigated by increasing the cooling rate in the order of H （slow cooling in furnace） → L （cooling in furnace） → K （cooling in air）. With the increase in cooling rate, the grain size and density decreased, the breakdown voltage （VImA/mm） increased, and the nonlinear coefficient （α） and leakage current （IL） exhibited extremum. The sample with the cooling type L showed the best properties with the breakdown voltage of 2650 V/ram, o：of 20.3, IL of 5.2 laA, and density of 5.42 g/cm^3. The barrier height （ФB）, donor concentration （Nd）, density of the interface states （Nd）, and barrier width （ω） all exhibited extremum during the alteration in cooling rate. The different relative amount of Bi-rich phase and its distribution as well as the characteristic parameters of grain boundary, resulting from the alteration of cooling rate, led to the changes in the properties of varistor ceramics.

关键词： varistor ZnO Dy2O3 microstructure electrical properties high-energy ball milling low-temperature sintering