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STRUCTURE AND MAGNETIC PROPERTIES OF Fe/Pd COMPOSITIONALLY MODULATED FILMS

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 112-115页

作者： ZHANG Lin LIU Yihua shandong University,jinan,china WANG Hao Dongnan University,Nanjing,china engineer,Department of Physics,shandong University,jinan 250100,china shandong Univ Jinan China

Metal Fe/Pd compositionally modulated films(CMFs) were prepared by vapour depo- sition from two sources onto glass substrate under *** modulation and crystal structures of the films were examined by X-ray *** magnetic properties were determined by vibrating sample *** Pd layers in the Fe/Pd CMFs are of fcc structure,and the Fe layer structure transits from bcc into amorphous,state with decreasing thickness of Fe *** dependence of specific saturation magnetization on thickness of Fe layers has also been discussed.

关键词： compositionally modulated films modulated structure specific saturation magnetization

Adsorption of CO molecules on Rh low index and (331)stepped surfaces

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Chinese Science Bulletin 2004年第10期49卷 1012-1019页

作者： WANG Zexin PANG Xuehui WANG Rui Chemistry Department, shandong Normal University, jinan 250014,china Correspondence should be addressed to Wang Zexin Chemistry Department Shandong Normal University Jinan 250014 China

The 5-parameter Morse potential (for short5-MP) of the interaction between C, O atom and Rh surfaceand the extended LEPS potential have been constructed, andthe adsorption and diffusion of CO molecules on Rh low in-dex surfaces and open rough Rh(331) stepped surface areinvestigated. This work puts forward the concept of vibra-tion dactylogram property for molecular adsorption *** calculation results and the analysis of vibration dactylo-gram show that there exists the commonness in the adsorp-tion on Rh low index surfaces and Rh(331) stepped surface: with the increasing coverage, the top, bridge sites are ad-sorbed in perpendicularly in sequence, and the top sites arethe steady adsorption sites and the bridge sites are the *** (100) surface, CO molecules obtain the eigenvibration of2009, 1946 cm^-1 on the top and bridge sites respectively andthe difference between the binding energy of above two sitesis 0.09 eV; on (110) surface, CO molecules obtain the eigen-vibration of 2019, 1961 cm^-1 respectively; on (111) surface,CO molecules on the top. bridge and hollow sites produce theeigenvibration of 2000, 1912, 1894 cm^-1 respectively, thebinding energies of the three sites decrease in turn and thediscrepancy between the top and bridge sites is 0.03 eV; on (331) surface, top and bridge sites between two equivalenttop sites are adsorbed in, and then obtain the eigenvibrationof 2018, 1987 cm^-1; 1969, 1927 cm^-1 respectively.

关键词：一氧化碳铑 5-MP 扩展LEPS电势表面吸附陆地指纹本征振动

Almost every graph has a fixed edge

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Chinese Science Bulletin 1998年第2期43卷 99-101页

作者： FAN Hongbing Department of Mathematics, shandong University, jinan 250100, china Department of Mathematics Shandong University Jinan China

An edge e of a graph G is called a fixed edge if G-e+e′ G implies e′=e, and an isomorphic fixed edge if G-e+e′ G implies that there exists an automorphism of G-e, which maps the ends of e to the ends of e′. It is proved that almost every graph is with all its edges as fixed edges and isomorphic fixed edges, and it is conjectured that all graphs contain isomorphic fixed edges.

关键词： graph isomorphism automorphism group fixed edge.

Existence and uniqueness for BSDE with stopping time

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Chinese Science Bulletin 1998年第2期43卷 96-99页

作者： CHEN Zengjing Department of Mathematics, shandong University, jinan 250100, china Department of Mathematics Shandong University Jinan China

The existence and uniqueness of the solutions for a class of backward stochastic differential equations (BSDEs for short) in a random interval are discussed.

关键词： BSDE stopping time adapted solution.

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

Numerical Simulation of the TIG Welding Arc Behavior

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Journal of Materials Science & Technology 2002年第1期18卷 43-46页

作者： Chuansong WU and Jinqiang GAOInstitute of Materials Joining, shandong University, jinan 250061, china [ Manuscript received January 2, 2001, in revised form February 14, 2001] Inst. of Mat. Joining Shandong Univ. Jinan 250061 China

Achieving an effective utilization and exploitation of TIG welding arcs require a thorough understanding of the plasma properties and its physical processes. Through simultaneous solutions of the set of conservation equations for mass, momentum, energy and current, a mathematical model has been developed to predict the velocity, temperature, and current density distributions in argon welding arcs. The predicted temperature fields in arc regions, and the distribution of current density and heat flux at the anode agree well with measurements reported in literatures. This work could lay the foundation for developing a comprehensive model of the TIG welding process where a dynamic, two-way coupling between the welding arc and the weld pool surface is properly represented.

关键词： Welding Argon arc Plasma Behavior

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.

THE GOLDBACH-VINOGRDOV THEOREM WITH THREE PRIMES IN A THIN SUBSET

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Chinese Annals of Mathematics,Series B 1998年第4期19卷 479-488页

作者： LIU JIANYA (Department of Mathematics, shandong University, jinan 250100, china.) 山东大学数学系山东济南

It is proved constructively that there exists a thin subset S of primes, satisfying for some absolute constant c＞0, such that every sufficiently large odd integer N can beLet r be prime, and hi positive integers with (bj, r) = 1,j = 1, 2, 3. It is also proved that, for almost all prime moduli r＜ log- N, every sufficiently large odd integer N = b1 + b2 +ba(modr) can be represented as where c ＞ 0 is an absolute constant.

关键词： Goldbach-Vinogradov theorem Exponential sum Primes Arithmetic progression Mean-value theorem

PBVP of Integrodifferential Equations with Carathéodory Functions

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Acta Mathematica Sinica,English Series 1998年第4期14卷 463-472页

作者： Zhuang Wan Chen Yubo, Department of Mathematics, shandong Normal University, jinan 250014, china 山东师范大学数学系山东济南

We study the periodic boundary value problems for nonlinear integro-differential equa- tions of Volterra type with Carathéodory functions. For two situations relative to lower and upper solutions α and β:αβ or β α, the existence of solutions and the monotone iterative method for establishing extreme solutions are considered.

关键词： Integrodifferential equations Periodic boundary value problems Carathéodory conditions Lower and upper solutions Sobolev spaces Topological degree