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surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

Progress in Natural science:materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2. FENG Zhijing1 and CHENG Kai3.1. state Key Laboratory of Tribiology, Tsinghua university, Beijing 100084, china 2. {2.ent of material sciences, changchun university of science and technology, changchun 13.02., china 3. Faculty of Information and Engineering systems, City Campus, Leeds Ls1 3.E, UK) state Key Laboratory of Tribiology Tsinghua University Beijing 100084 China department of material sciences Changchun University of Science and Technology Changchun 130021 China Faculty of Information and Engineering systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.2. nm root mean square (RMs) after 2. min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

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Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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Chinese science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, sONG Jinming, ZHOU shixin and LUO Binjie1. Lanzhou Institute of Geology, Chinese Academy of sciences, Lanzhou 73.000, china 2. Earthquake Research Institute of Lanzhou, ssB, Lanzhou 73.000, china 3. Institute of Oceanology, Chinese Academy of sciences, Qingdao 2.6071, china Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research Institute of Lanzhou SSB Lanzhou China Institute of Oceanology Chinese Academy of Sciences Qingdao China

sINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

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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 {2. of science and technology, Wuhan 43.074, china 2. Institute of Laser technology and Engineering, Huazhong {2. of science and technology, Wuhan 43.074, china 3. Mechanical Engineering College, Hubei {2. of technology, Wuhan 43.068, 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 Engineering 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.

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Investigation on Vibrational spectra and structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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Chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3.and GONG Bao-an 2.1. Key Laboratory for supramolecular structure and material of Ministry of Education, Jilin {3., {2. 13.012. P. R. china 2. science and Engineering College of Chemistry and Biology, Yantai {3., Yantai 2.4005, P. R. china 3. state Key Laboratory of Theoretical and Computational Chemistry, Jilin {3., changchun 13.02., P. R. china [a]Key Laboratory for supramolecular structure and material of Ministry of Education Jiln University Changchun 130012 P. R. China[b]Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China[c]State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3.YP method with the 6-3.1++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

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Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2.1. Key Laboratory of Beam technology and material Modification of Ministry of Education, Beijing Normal {2., Beijing 100875, china 2. Physics department, Beijing Normal {2., Beijing 100875, china 3. china Institute of Atomic Energy, Beijing 102.13. china Key Laboratory of Beam technology material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics department Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(3.si,4n)2.0Hs, 2.8U(3.s,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(3.s,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,smoluchowski equation,superheavy nuclei.

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Development and Application of High Performance X80 Line Pipe for the 2.(nd) West-East Gas Pipeline

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Journal of Iron and steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2., LI Yang 1, 3.(1. CNPC Tubular Goods Research Institute, Xi’an 710065, china 2. . school of {3. science and Engineering, Xi’an Jiaotong {2., Xi’an 710049, china 3. school of {3. science and Engineering, {2. of science and technology Beijing, Beijing 100083. china) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2.d West-East Gas Pipeline (the 2.nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12.MPa and X80 LsAW and HsAW pipe for the 2.nd WEGP. specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the specification. General design conception of applying HsAW pipe and LsAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2.nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HsAW and LsAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2.nd WEGP acicular ferrite failure control arrest toughness strain-based design

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Mineral provinces and material provenance of the surficial sediments near the Zhongsha Islands in the south china sea

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Acta Oceanologica sinica 2007年第1期26卷 66-76页

作者： YAN Quanshu1, 2. 3. sHI Xuefa2., WANG Kunshan2.. Institute of Oceanology, Chinese Academy of sciences, Qingdao 2.6071, china2. Key Laboratory of Marine sedimentology and Environment Geology of state Oceanic Administration, First Institute of Oceanograghy, state Oceanic Administration, Qingdao 2.6061, china3. Graduate school, Chinese Academy of sciences, Beijing 100049, china Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Characteristics and distribution patterns of clastic minerals (0.063.0.12. mm) in bottom sediments represent a significant indicator for the identification of the origin of sediment. One hundred and fourteen surface sediment samples, which were collected from the area near the Zhongsha Islands in the south china sea, were analysed to identify the mineral suites and their distributions in the study area. The area can be divided into three mineral provinces: (Ⅰ) a province of biogenic minerals, which mainly originate from the Zhongsha Atoll; (Ⅱ) a province of volcanogenic minerals, which are mainly derived from local basaltic seamounts and small-scale volcanoes that are probably erupting, with some influences from the island-arc volcanic region around the south china sea; and (Ⅲ) a mixed mineral province whose {2. source includes biogenic minerals, volcanogenic minerals and terrigenous minerals; the last province can be subdivided into a mixed mineral sub-province of the northeastern part of the study area, in which terrigenous minerals are mainly derived from china’s Mainland and do not exceed 17°N, and a mixed mineral sub-province of the southeastern part of the study area, in which terrigenous minerals are derived from Kalimantan and Indochina Peninsula and might be further transported into the deep sea basin through submarine canyons.

关键词： south china sea Zhongsha Islands light mineral minerals province material provenance

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The mathematical model of wetting angle of heterogeneous nucleation

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science china(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, sONG Bo1, MAO Jinghong2.& ZHAO Pei3.1. school of Metallurgical and Ecological Engineering, university of science and technology Beijing, Beijing 100083.{2. 2. school of material science, university of science and technology Beijing, Beijing 100083.{2. 3. Central Iron and steel Research Institute, Beijing 100081,{2. 1. school of Metallurgical and Ecological Engineering University of Science and Technology Beijing 100083 Beijing China 2. school of material science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and steel Research Institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3.are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

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Analysis for twinning and slip in face-centered cubic crystals under axisymmetric co-deformation

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science china(Technological sciences) 2006年第5期49卷 521-536页

作者： CHEN Zhiyong1,2. CAI Hongnian1, ZHANG Xinming2. WANG Fuchi1 & TAN Chengwen1,3.1. school of material science and Engineering, Beijing Institute of {3., Beijing 100081,{2. 2. school of material science and Engineering, Central south university, Changsha 410083.{2. 3. school of material science and Engineering, Beijing university of Aeronautics and Astronautics, Beijing 100083.{2. 1. school of material science and Engineering Beijing Institute of Technology Beijing 100081 China 2. school of material science and Engineering Central South University Changsha 410083 China 3. school of material science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The maximum work principle of Bishop-Hill was developed to analyze the axisymmetric co-deformation in face-centered cubic crystals (f.c.c.) for twinning on {111} 112.and slip on {111} 110 systems. The influence of ξ , the ratio of critical re- solved shear stress for twinning to slip, on the yield stress states and corresponding active slip or/and twinning systems for orientations in the standard stereographic triangle of cubic crystal was investigated systematically. The Taylor factors and the anisotropy of yield strength for three important orientations [100], [110] and [111] in orientation space were analyzed. It is found that the yield strength asymmetry for the case of axisymmetric de- formation of tension and compression can be explained based on the microscopic theory of crystal plasticity. The concept of orientation factor for twinning ability was proposed and the deformation mechanism map in the orientation space was established for the case of axisymmetric deformation. The deformation texture formation and development of f.c.c. crystals with low stacking fault energy for axisymmetric tension can be explained qualita- tively on the basis of analyzed results.

关键词： twinning slip face-centered cubic crystals axisymmetric co-deformation Bishop-Hill maximum work principle yield strength anisotropy

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Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan university of technology({2.s science) 2010年第1期25卷 162-166页

作者：郭伟 department of material Engineering Yancheng Institute of Technology Institute of material science and Engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2.content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DsC）, X-ray diffraction（XRD）, scanning electronic microscopy （sEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-s-H gel, Ca（OH）2.and AFt. The cement with 3.% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

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