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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3.& FENG Hao4 1. Institute of physics, college of Chemical engineering, Sichuan University, Chengdu 610065, {3. 2. Institute of Theoretical physics, Xihua Normal University, Nanchong 63.002, {3. 3. Department of physics, {3. Oceanography University, Qingdao 266003. {3. 4. college of physics, Sichuan University, Chengdu 610065, {3. 1. Institute of physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical physics Xihua Normal University 637002 Nanchong China 3. Department of physics China Oceanography University 266003 Qingdao China 4. college of physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

New ternary compound La_8Al_(13.Sn_3

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Rare Metals 2009年第5期28卷 491-493页

作者： HE Wei XIA Xiuwen ZHANG Jiliang HUANG Jinli LIU Yixin Key Laboratory of Nonferrous Metal Materials and New Processing Technology （Ministry of education） College of Materials Science and Engineering Guangxi University Nanning 530004 China Department of physics and electronic Information Science Guangxi Teachers Education University Nanning 530023 China

A new ternary compound La8Al13.n3.was synthesized and studied by means of X-ray powder diffraction technique. The compound La8Al13.n3.crystallizes in a hexagonal AlB2-type structure with space group P6/mmm （No. 191） and the lattice parameters a = 0.44919（1） nm and c = 0.43.3.（1） nm. The Smith and Snyder figure of merit for index, FN, is F3. = 197.3.3.）. The Rietveld refinement for the crystal structure of the compound was carried out successfully. The liability R-factors of Rietveld refinement are Rp = 0.114 and Rwp = 0.148. The compound La8Al13.n3.decomposes into LaAl2 with cubic structure and space group Fd 3. （227）, LaAl3.with hexagonal structure and space group P63.mmc （194）, and Sn at 720°C.

关键词： crystallography X-ray diffraction Reitveld method rare earth compounds

Investigation on the 773.K isothermal section of La-Fe-Sn ternary systems by X-ray powder diffraction

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Rare Metals 2010年第6期29卷 567-571页

作者： CHEN Xiang ZHUANG Yinghong CHEN Yungui Key Laboratory of Nonferrous Metal and New Processing Technology of Materials (Ministry of education of china) Guangxi University Nanning 530004 China Department of physics and electronic Information engineering Neijiang Teachers College Neijiang 641002 China Department of Metallic Materials engineering Sichuan University Chengdu 610065 China

The 773.K isothermal section of the La-Fe-Sn ternary system was investigated and constructed by X-ray powder diffraction（XRD）.The existence of two reported ternary intermetallic compounds,La6Fe13.n and La3.eSn6,is confirmed in this *** with other R-Fe-Sn phase diagrams（R = Pr and Sm）,the binary alloys Fe3.n and Fe5Sn3.are not *** compound Fe3.n2 was observed from the XRD pattern of Fe3.n2 samples,but it is not an equilibrium phase at 773.K and decomposes into Fe and FeSn phases completely for a longer heat treated *** to now,the crystal structure data of La2Sn3.has not been reported,so the X-ray pattern of La2Sn3.was only *** phase relationship for this compound was drawn by a dotted line.

关键词： intermetallics quenching phase diagrams X-ray diffraction.

Bloch constant of holomorphic mappings on the unit polydisk of C^n

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Science china Mathematics 2008年第4期51卷 652-659页

作者： WANG JianFei~(1+) LIU TaiShun~2 1 college of Mathematics and physics Information engineering Zhejiang Normal University Jinhua 3.1004,{3. 2 Department of Mathematics Huzhou teachers college Huzhou 3.3.00 {3. college of Mathematics and physics Information Engineering Zhejiang Normal University Jinhua China Department of Mathematics Huzhou Teachers College Huzhou China

In this paper,we give a definition of Bloch mappings defined in the unit polydisk D^n, which generalizes the concept of Bloch functions defined in the unit disk *** is known that Bloch theorem fails unless we have some restrictive assumption on holomorphic mappings in several complex *** shall establish the corresponding distortion theorems for subfamiliesβ(K)andβ_(loc)(K) of Bloch mappings defined in the polydisk D^n,which extend the distortion theorems of Liu and Minda to higher *** an application,we obtain lower and upper bounds of Bloch constants for various subfamilies of Bloeh mappings defined in D^*** particular,our results reduce to the classical results of Ahlfors and Landau when n=1.

关键词： Bloch constant Bloch mapping univalent ball critical point Julia lemma locally biholomorphic mapping Landau constant

Magnetocaloric effect of (Gd_(1-x)Nd_x)Co_2 alloys in low magnetic field

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Rare Metals 2008年第4期27卷 350-353页

作者： CHEN Xiang ZHUANG Yinghong YAN Jialin ZHOU Kaiwen LI Kefeng Key laboratory of the Ministry of education of china for Nonferrous Metal Materials and New Processing Technology Guangxi University Nanning 530004 China Department of physics and electronic Informational engineering Neijiang Teachers College Neijiang 641002 China

The phases and magnetocaloric effect in the alloys （Gd1-xNdx）Co2 with x = 0, 0.1, 0.2, 0.3. and 0.4 were investigated by X-ray diffraction analysis and magnetization measurement. The samples are single phase with a cubic MgCu2-type structure. The To decreases obviously with increasing Nd content from 404 K of the alloy with x = 0 to 272 K of the alloy with x = 0.4; forx = 0.3. the To is 296 K, which is near room temperature. In the samples （Gd1-xNdx）Co2 with x = 0.0, 0.1, 0.2, 0.3. and 0.4, the maximum magnetic entropy change is 1.471, 1.228, 1.280, 1.3.1 and 1.610 J·kg^-1·K^-1, respectively, in the applied field range of 0-2.0 T. The results of Arrott plots confirmed that the transition type were second order magnetic transition forx = 0, 0.3. and 0.4.

关键词： magnetic refrigeration materials magnetocaloric effect magnetic entropy change phase transition

Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1,3. SUN Weiguo1,2 & FENG Hao1 1. Institute of physics, Sichuan University, Chengdu 610065, china 2. college of Chemical {3., Sichuan University, Chengdu 610065, china 3. Mianyang Teacher抯 college, Mianyang 621000, china Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) 1. Institute of physics Sichuan University 610065 Chengdu China 2. Mianyang Teacher's college 621000 Mianyang China 3. college of Chemical engineering Sichuan University 610065 Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2π state of CO+, the X2∑ g + state of Li 2 + , the X2∑ g + state of He 2 + , the 12∏u state of Na 2 + , the A2∏u state of N 2 + , the X1∑+ state of KrH+, the X2∑+ state of SiO+ and the A2π state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

Modulation on the collective response behavior by the system size in two-dimensional coupled cell systems

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 304-312页

作者： ZHANG Jiqian1, SHEN Chuansheng1,2 & CUI Zhifeng1 1. college of physics and electronic Information, Anhui Normal University, Wuhu 241000, {3. 2. Department of educational Technology, Anqing teachers college, Anqing 246011, {3. college of physics electronic Information Anhui Normal University Wuhu 241000 China Department of educational Technology Anqing Teachers College Anqing 246011 China

By the intracellular calcium ionic minimal model proposed by Berridge, we investigated the collective response of two-dimensional (N×N) coupled cell systems to the external stimulation using numerical simulation methods. With a coupled intensity fixed and an appropriate coupled cell number chosen, the kinetic system size resonance was discovered. At the same time, it was found that the system size responding to the external stimulation for different coupled intensities transferred too, especially when the coupled intensity increased, the range of the corresponding system size extended. These phe- nomena illustrate that the coupled cell number and the coupled intensity can play con- structive roles in noisy coupled systems, by which the biology system would probably improve its capability to respond to the external stimulation.

关键词： cell coupling,collective response,system size resonance

Preparation of nanocrystalline BaTiO_3.ceramics

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Science china(Technological Sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2,LI DeJun1,LI JianBao2,WANG XiaoHui3.& LI LongTu3.1 college of physics and electronic Information,Tianjin Normal University,Tianjin 3.03.7,{3. 2 Materials and Chemical engineering Institute,Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical engineering Material of Ministry of education,Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti,Hainan University,Haikou 570228,{3. 3.Department of Materials Science and engineering,Tsinghua University,Beijing 100084,{3. college of physics and electronic Information Tianjin Normal University Tianjin 300387 China Materials and Chemical engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan University Haikou 570228 China Department of Materials Science and engineering Tsinghua University Beijing 100084 China

The high-dense nanocrystalline BaTiO3.BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect

Investigation of nano-talc as a filling material and a reinforcing agent in high density polyethylene (HDPE)

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Rare Metals 2006年第z1期25卷 422-425页

作者： CHEN Nanchun MA Lei ZHANG Tao Center for Material engineering Guilin Institute of Technology Guilin 541004 China Key Laboratory of Nonferrous Materials and Processing Technology Ministry of Education Guilin Institute of Technology Guilin 541004 China Department of Physics and Information Technology Yulin Teachers'' College Yulin 537000 China Center for Material Engineering Guilin Institute of Technology Guilin 541004 China Key Laboratory of Nonferrous Materials and Processing Technology Ministry of Education Guilin Institute of Technology Guilin 541004 China

An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-treated with aluminum diethylene glycol dinitrate coupling agent before adding to the HDPE. Analyses of the reinforced HDPE nano-composite show significant improvement in its mechanical properties including, tensile strength (>26 MPa), break elongation (22 MPa), and friction coefficients<0.11. The results demonstrate that, after surface-treated, talc can be used as a promising filling material and a reinforcing agent in making HDPE nano-composite.

关键词： HDPE talc filling material reinforcing agent nano-composite mechanical properties