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Valance electron structure of carbide-diamond interface and catalytic mechanism for diamond synthesis under high-pressure and high-temperature

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Progress in Natural Science:Materials International 2006年第8期16卷 852-858页

作者： GONG Jianhong, XU Bin, YIN Longwei, QI Yongxin, LI Li, SU Qingcai and LI Musen (school of Materials Science and engineering, shandong university, jinan 250061, china Department of Materials Science and engineering, shandong Institute of Architecture and Technology, jinan 250014, china shandong engineering and Technology Research Center of Super-hard Materials, Zoucheng 273500, china) school of Materials Science and engineering Shandong University Jinan 250061 China shandong engineering and Technology Research Center of Super-hard Materials Zoucheng 273500 China Department of Materials Science and engineering Shandong Institute of Architecture and Technology Jinan 250014 China

The metallic films surrounding a synthetic diamond formed under high-pressure and high-temperature (HPHT) in the presence of Fe-based and Ni-based catalysts were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was showed that the carbide was the primary carbon source for the nucleation and growth of diamond. Based on the EET (empirical electron theory in solid and molecules) theory, the valence electron structure of interface between carbide (Fe3C, Ni3C, (Fe, Ni)3C) and diamond was calculated using the bonding length difference (BLD) method. The boundary criterion of Thomas-Fermi-Dirac-Cheng (TFDC): "the electron density being equal on the contacting surfaces of atoms" was applied to analyze the valence structure of carbide-diamond interface. The result based on the calculation valance electron structure is in good accordance with the experimental result. This study is very helpful to reveal the catalytic mechanism of diamond nucleation and growth and design the new catalyst for diamond synthesis.

关键词： synthetic diamond carbide catalytic mechanism valence electron theory interface.

Synthesis of a novel centipede-like copolymer of styrene and methyl methacrylate

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Science china Chemistry 2007年第2期50卷 253-257页

作者： LI AiXiang1 & LU ZaiJun2 1 school of Material Science and engineering,shandong university of Technology,Zibo 255049,china 2 school of Chemistry and Chemical engineering,shandong university,jinan 250100,china school of Material Science and engineering Shandong University of Technology Zibo China school of Chemistry and Chemical engineering Shandong University Jinan China

A well-defined,A2B-type,centipede-like copolymer of styrene and methyl methacrylate(PS-PS-PMMA) was synthesized by the combination of living anionic polymerization and atom transfer radical polym-erization(ATRP) . The synthetic approach involves the coupling reaction of polystyrene(PS) backbone bearing 1,1-diphenylethene(DPE) pendant groups,produced by ATRP and Wittig reaction,with living polystyryllithium(PSLi) ,and subsequent polymerization of the resulting 1,1-diphenylmethyl anions with methy methacrylate. The centipede-like copolymer was characterized by 1H NMR,IR,SEC,SLS,and DSC measurements.

关键词： architecture atom transfer radical polymerization centipede-like copolymer coupling reaction living anionic polymerization

EXPERIMENTAL STUDY ON ENHANCED HEAT TRANSFER WITH NI-BASED IMPLANTED SPIRAL FINNED TUBES

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Journal of Hydrodynamics 2003年第5期15卷 65-69页

作者： Sun Feng zhong, Huang Xin yuan, Wang Nai hua, Shi Yue tao, Ping Ya ming school of Energy and Power engineering, shandong university, jinan 250061, china Sch. of Energy and Power Eng. Shandong Univ. Ji'nan 250061 China

The new type of heat exchanger elements-Ni-based Implanted Spiral FinnedTurbes (NISFT) was studied and tested, which can contribute to increase the efficiency andreliability. The relation of Nu, Eu and Re with different fin pitch, fin height, transverse pitchand longitudinal pitch were gained, which constituted the basic foundation for the engineeringapplication of NISFT.

关键词： enhanced heat transfer heat exchanger finned tube

Morita contexts on the Hopf algebroid

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Science china Mathematics 2005年第7期48卷 958-971页

作者： YIN Yanmin school of Mathematical Sciences, Peking university, Beijing 100871, china Department of Mathematics, shandong Institute of Architecture and engineering, jinan 250101, china school of Mathematical Sciences Peking University Beijing 100871 China Department of Mathematics Shandong Institute of Architecture and Engineering Jinan 250101 China

We generalize the Morita theory to the Hopf algebroid and give the characterization of the surjectivity of one of the Morita context maps.

关键词： comodule algebra, generalized smash product, Morita context.

Microstructures of laser cladding of intermetallic-ceramic composite coatings

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International Journal of Minerals,Metallurgy and Materials 1997年第3期11卷 8-10页

作者： ZHOU Xianglin CHEN Chuanzhong CHANG Chun YU Jiahong HU Hanqi ( Department of Materials, shandong university of Technology, jinan 250061, china) (Materials Science and engineering school, university of Science and Technology Beijing, Beijing 100083, shandong Univ of Technology Jinan China

The microstructures of laser cladding of (Ni-24.5%(atom fraction)Al)+5O%(mass haction)WC coatingsbefore and after aging was comparetively studied by using SEM and TEM. It is shown that dissolving of WC and reprecipitating in the forms of WC and W,Coccurred during laser cladding, and intermetallic γ' (Ni3Al) orderly precipitatefrom metastable supersaturant Ni-matrix solid solution after heat treatment. The structures are favorable for coating'sproperties.

关键词： intermetallic ceramic laser cladding metastable Phase aging

Microstructure and diffraction pattern changes resulted from long-term aging of martensite CuZnAlMnNi shape memory alloy

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Rare Metals 2002年第4期21卷 308-312页

作者： BAIYujun WANGShouren 等 mechanicalDepartment ShandongUniversityofScienceandTechnologyJinan250031China Instituteofmechanicalengineering JinanUniversityJinan250022China

Microstructures of a CuZnAlMnNi shape memory alloy in the as-quenched andlong-term aged conditions were investigated by transmission electron microscopy. Aged for one yearin martensite phase, an equilibrium α-phase with fcc structure was observed in the M18R martensitematrix, accompanied by the appearance of a novel diffraction pattern. By analysis, it was suggestedthat the novel pattern results from the α-phase and the martensite matrix remaining in seven fineplates which produce intense secondary diffraction effect when the diffraction beams enter from onephase into another.

关键词： CuZnAlMnNi shape memory alloy martensite aging transmission electronmicroscopy

Study on the cluster of floating dross before nucleating during hot-dipping process

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Science china Chemistry 2005年第1期48卷 83-88页

作者： WEI Yunhe1, ZHANG Changqiao1, QIN Jingyu2 & LIU Chengbu1 1. school of Chemistry and Chemical engineering, shandong university, jinan 250100, china 2. The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education, shandong university, jinan 250061, china school of Chemistry and Chemical engineering Shandong University Jinan China The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education Shandong University Jinan China

During hot-dipping in molten Zn-55Al, the forming of “floating” dross is closely re- lated with the interaction between the Al and the Fe atoms. Utilizing the thita-thita X-ray diffraction and the Percus-Yevick hard sphere model, this paper investigates the structure of molten Al3Fe that is an approximant of partial melt in practical Zn-55Al alloy melt. It is found that in the melt there exist clusters that resemble the structure of intermetallic compound Al3Fe. The strong in- teraction between Al and Fe atoms is also indicated by the deficiency of the coordination number from 12 and the shrinkage of averaged atomic diameter. Based on such information, it is specu- lated that in the molten Zn-55Al, with the accumulation of Fe, Al3Fe-like clusters form with priority, then grow into dross. On the other hand, after deflating of the effective hard sphere diameter of pure Al atom and enlarging that of the pure Fe atom, the modified model can achieve reasonable fit to the experimental structure factor. Hard sphere modeling also gave a good estimation of the mass density 3.65 g/cm3 of liquid Al3Fe alloy at 1550℃. Compared with the density of 3.7 g/cm3 of Zn-55Al, the reason for dross floating is satisfactorily understood.

关键词： hot-dipping, dross, Al3Fe alloy, molten structure, P-Y model.

A New Measurement Method for Unbalanced Moments in a Two-axis Gimbaled Seeker

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Chinese Journal of Aeronautics 2010年第1期23卷 117-122页

作者： Yu Shuang,Zhao Yanzheng school of mechanical engineering,Shanghai Jiaotong university,Shanghai 200240,china school of mechanical engineering Shanghai Jiaotong University Shanghai 200240 China

This article presents a novel method to measure unbalanced moments in a two-axis gimbaled seeker commonly believed to seviously influence the tracking accuracy and stabilizing capability. This method enables individual measurement of unbalanced moments, and judgment of the seeker＇ s status-balanced or not. Furthermore, an instrument is designed based on this method and calibrated. The effectiveness of the proposed method is validated through a simulation. The experimental results show a satisfied level of accuracy the measurements have. This work forms a basis for the further development of a more stabilized gimbaled seeker with less induced vibration and consumed power.

关键词： gimbaled seeker weight sensors measurement unbalanced

Adsorption studies of the removal of anions from aqueous solutions onto an adsorbent prepared from wheat straw

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Science china Chemistry 2010年第6期53卷 1414-1419页

作者： XU Xing,GAO Yue,GAO BaoYu,YUE QinYan & ZHONG QianQian school of Environmental Science and engineering,shandong university,jinan 250100,china school of Environmental Science and engineering Shandong University Jinan China

Modified wheat straw (MWS) was prepared by the grafting of epichlorohydrin,triethylamine and ethylenediamine onto *** characteristics of MWS and its adsorption capacity for NO-3,PO34and Cr2O72were *** results indicate that amine groups with positive charge have been introduced into the structure of MWS,and significantly increased its anion adsorption *** functions of MWS dosage,the solution pH,the contact time and temperature have significant influence on the adsorption process,and the adsorption is well fitted with the Langmuir equation and pseudo second-order *** maximum adsorption capacity of MWS for NO-3,PO34(P) and Cr2O27(Cr) is 53.5,62.4 and 386.2 mg g-1,respectively.

关键词： wheat straw anion adsorption maximum adsorption capacity