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Theoretical study on S_1(~1B_(3u)) state electronic structure and absorption spectrum of pyrazine

Science china Chemistry 2008年第12期51卷 1166-1173页

作者： HE RongXing1, ZHU ChaoYuan 2, CHIN Chih-Hao3 & LIN Sheng-Hsien2,3 1 College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, china 2 Department of Applied Chemistry, institute of molecular Science and Center for Interdisciplinary molecular Science, National Chiao-Tung University, Hsinchu 300, china 3 institute of atomic and molecular sciences, academia sinica, taipei 106, china College of Chemistry and Chemical Engineering Southwest University Chongqing China Department of Applied Chemistry Institute of Molecular Science and Center for Interdisciplinary Molecular Science National Chiao-Tung University Hsinchu China institute of atomic and molecular sciences Academia Sinica Taipei China

Making use of a set of quantum chemistry methods, the harmonic potential surfaces of the ground state (S0(1Ag)) and the first (S1(1B3u)) excited state of pyrazine are investigated, and the electronic structures of the two states are characterized. In the present study, the conventional quantum mechanical method, taking account of the Born-Oppenheimer adiabatic approximation, is adopted to simulate the absorp-tion spectrum of S1(1B3u) state of pyrazine. The assignment of main vibronic transitions is made for S1(1B3u) state. It is found that the spectral profile is mainly described by the Franck-Condon progression of totally symmetric mode ν6a. For the five totally symmetric modes, the present calculations show that the frequency differences between the ground and the S1(1B3u) state are small. Therefore the displaced harmonic oscillator approximation along with Franck-Condon transition is used to simulate S1(1B3u) absorption spectra. The distortion effect due to the so-called quadratic coupling is demonstrated to be unimportant for the absorption spectrum, except the coupling mode ν10a. The calculated S1(1B3u) ab-sorption spectrum is in reasonable agreement with the experimental spectra.

关键词： pyrazine absorption spectrum quantum mechanical method electronic structure

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The anharmonic effect study of coupled Morse oscillators for the unimolecular reaction

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Science china Chemistry 2008年第12期51卷 1146-1152页

作者： YAO Li1,2 & LIN Sheng-Hsien2,31 Department of Physics, Dalian Maritime University, Dalian 116026, china 2 institute of atomic and molecular sciences, academia sinica, taipei 10764, china 3 Department of Applied Chemistry and institute of molecular sciences, Chiao-Tung University, Hsinchu 30051, Taiwan, china Department of Physics Dalian Maritime University Dalian China institute of atomic and molecular sciences Academia Sinica Taipei China Department of Applied Chemistry and institute of molecular sciences Chiao-Tung University Hsinchu Taiwan China

The importance of anharmonic effect in dissociation of molecular systems especially clusters has been noted. In this paper, we shall study the effect of coupled anharmonic oscillator of the standard bilinear form (SBF) Morse oscillator (MO) potential on unimolecular reaction. We shall use the systematic theoretical approach, YL method, proposed by Yao and Lin (YAO L, et. al. J Phys Chem A, 2007, 111(29): 6722-6729), which can evaluate anharmonic effects on the rate constants based on the transition state theory. In treating the anharmonic effect with the Morse oscillator potential on unimolecular reactions under collision-free conditions by using the RRKM (Rice-Ramsperger-Kassel-Marcus) theory, the in-verse Laplace transformation of the partition functions was used to obtain the total amount of state and density of state by using the first-order and the second-order approximations of the saddle-point method. To demonstrate the anharmonic effect of the SBF Morse model, we choose some model systems and a real reaction as examples.

关键词： anharmonic effect standard bilinear form Morse oscillator rate constant RRKM theory

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FINE STRUCTURES OF BOTH INTERFACES AND INTERFACIAL REACTION PRODUCTS

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Acta Metallurgica sinica(English Letters) 1993年第1期6卷 1-20页

作者： LI Douxing PING Dehai NING Xiaoguang YE Hengqiang Laboratory of atomic Imaging of Solids,institute of Metal Research,academia sinica,Shenyang.china Professor,institute of Metal Research,academia sinica,Shenyang 110015,china Inst of Metal Research Acad Sinica Shenyang China

The characteristic of interface depending on the atomic structure exerts an inportant,and sometime controlling,influence on performance of the interacial materials. The present paper reviews the main studies on fine structure of both the materials inter- faces and interfacial reaction products in semiconductor uperlattice,metal multilayer ceram- ics and composite materials by mean of selected area electron doffraction patterns and high resolution electron microscopy. The following features of interfaces are reviewed:the orientation relationships;the char- acteristic of steps,facets and ronghness of interfaces;atomic bonding across the interface;the degree of coherency,the structure of misfit dislocations and elastic relaxations at the inter- faces:the presence of defects at the onterfaces:the structure of the interfacial reaction prod- ucts as well as the reaction kinetics and reaetion mechanism.

关键词： fine structure of the interfaces interfacial solid state reaction orientation relationship high resolution electron microscopy

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Studies on the Temperature Effect on Bacteriorhodopsin of Purple and Blue Membrane by Fluorescence and Absorption Spectroscopy

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Acta Biochimica et Biophysica sinica 2006年第10期38卷 691-696页

作者： Lan-Ying CHENG~(1,2) Yue ZHANG~3 Shi-Gui LIU~1 Kun-Sheng HU~3 Kang-Cheng RUAN~2* 1 College of Life Science,Sichuan University,Chengdu 610064,china 2 State Key Laboratory of molecular Biology,institute of Biochemistry and Cell Biology,Shanghai institutes for Biological sciences,Chinese Academy of sciences,Shanghai 200031,china 3 institute of Biophysics,academia sinica,Beijing 100101,china College of Life Science Sichuan UniversityChengdu 610064 China State Key Laboratory of molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China institute of Biophysics Academia SinicaBeijing 100101 China

Fluorescence and absorption spectra were used to study the temperature effect on theconformation of bacteriorhodopsin (bR) in the blue and purple membranes (termed as bRb and bRprespectively).The maximum emission wavelengths of tryptophan fluorescence in both proteins at roomtemperature are 340 nm,and the fluorescence quantum yield of bRb is about 1.4 fold higher than that of *** temperature increases,the tryptophan fluorescence of bRb decreases,while the tryptophan fluorescenceof bRp *** binding study of extrinsic fluorescent probe bis-ANS indicated that the probe can bindonly to bRb,but not to *** results suggest that significant structural difference existed between bRband *** was also found that both kinds of bR are highly thermal *** maximum wavelength of theprotein fluorescence emission only shifted from 340 nm to 346 nm at 100℃.More interestingly,as tempera-ture increased,the characteristic absorption peak of bRb at 605 nm decreased and a new absorption peak at380 nm *** transition occurred at a narrow temperature range (65℃-70℃).These facts indicatedthat an intermediate can be induced by high *** phenomenon has not been reported before.

关键词： bacteriorhodopsin purple membrane blue membrane fluorescence and absorption spectroscopy

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PREPARATION,PROPERTIES AND INTERFACE STRUCTURES OF Si_3N_(4w)/6061Al COMPOSITE

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Acta Metallurgica sinica(English Letters) 1992年第11期5卷 423-428页

作者： PAN Jin Changsha institute of Technology,Changsha,chinaNING Xiaoguang YE Hengqiang Laboratory of atomic Imaging of Solids,institute of Metal Research,academia sinica,Shenyang,china Changsha Inst of Technology Changsha China

The Si_3N_4 whisker reinforced 6061Al composite with bending strength of 790 MPa was prepared by squeeze casting *** heat-treatment under T6 regime i.e.530℃, 1 h solutioning and 160℃,24 h aging,an increment in strength and microhardness may be over 20% and 28% respectively,The microstructures of Si_3N_4 whisker and Si_3N_4/Al interface were observed by meas of *** relation between interracial structure and composite properties was discussed.

关键词： β-Si_3N_4 wthisker Al matrix composite strength interface

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HIGH RESOLUTION STUDY OF TWINS IN Al_(20)Cu_2Mn_3 PHASE

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Acta Metallurgica sinica(English Letters) 1992年第4期5卷 227-230页

作者： LI Chunzhi WANG Shuncai JIN Yan institute of Aeronautical Materials,Beijing,Laboratory of atomic Imaging of Solids,institute of Metal Research,academia sinica,Shenyang,china Inst of Aeronautical Materials Beijing China

The dispersoid phase Al_(20)Cu_2Mn_3 in a 2024 Al alloy is commonly composed of twins,An ob- servation of corresponding high resolution image shows that the twin boundary plane is a glide plane other than mirror *** neighbouring components of twins are not symmetry of re- flection or rotation,but of glide ***“diamond”glide plane is(101)and the glide vector is(1/4)(-).Components of twins in the phase take shape of prism with the longitudinal edge being parallel to[010]and side faces being{101}and{100}.

关键词： twin glide reflection high resolution image Al-Cu-Mn alloy

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PHOSPHORUS SEGREGATION AND ANNEALING EMBRITTLEMENT OF Ni-P AMORPHOUS

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Acta Metallurgica sinica(English Letters) 1991年第8期4卷 103-107页

作者： Qu Zhe XIE Tiansheng institute of Metal Research,academia sinica,Shenyang,china Acad sinica Shenyang China

Phosphorus segregation and embrittlement of Ni-P amorphous annealed at the temperatures below crystallization have been *** phosphorus enrichs on free surface and its level increases with annealing *** is fairly coincident with the measured toughness which decreases with annealing *** ion-sputtering revealed that a phosphorus depletion zone in the subsurface layers forms due to element redistribution during *** thickness and amplitude of the phosphorus depletion zone depend on the an- nealing temperature. The formation of depletion zone and the mechanism of embrittlement of Ni-P amorphous during annealing have been discussed based on the theory of the activation energy of atomic diffusion in the amorphous being variable.

关键词： Ni-P amorphous phosphorus segregation annealing embrittlement

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NEUMANN SERIES SOLUTION FOR THE INTEGRAL BOLTZMANN TRANSPORT EQUATION

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Acta Mathematica Scientia 1986年第3期6卷 279-285页

作者：姚爱翔 institute of atomic Energy academia sinica Beijing china

In this paper,a method based on Neumann series is proposed for solving stationary linear integral Boltzmann transport equations with variable energy for the case of both distributed and isotropic deltalike sources, by working in L~p(1≤p≤∞). The convergence of the Neumann series and convergent rate are established. In addition, a relation between stationary transport equation and time-dependent one is given.

关键词： NEUMANN SERIES SOLUTION FOR THE INTEGRAL BOLTZMANN TRANSPORT EQUATION

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STABLE NONLINEAR RELAXATIONS IN A MULTIPHASIC Al-Zn ALLOY

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中国有色金属学会会刊：英文版 1993年第2期3卷 58-64页

作者： Zhu,Xianfang institute of Solid State Physics,academia sinica,Hefei 230031,china

The experiments reveal the characteristics of stable damping in a multiphasic Al-Zn eutectoid alloy:（1）Thewhole damping(Q-1)has the same dependence on measured frequency（f）,i.e.Q-1ocf-n,where n is a parameterand is independent of temperature.（2）In a low-temperature（low-T）and low-strain-amplitude（low-A）region,Q-1=（B/）exp（-nH/kT）,where B is a parameter,H the atomic diffusion activation energy,k Boltzmann′sconstant,and T the absolute temperature.n,Ho（=nH）and H are all independent of A.The damping comesfrom an anelastic motion of the phase-interface.（3）In an intermediate region including a low-Tand a high-A,a middle-T and middle A and a high-T and low-A regions,the equation Q-1=（C/fn）exp（nH/kT）stillholds,but the damping has a normal amplitude effect C,n,and H all vary with A;the damping results from anonlinear relaxation of phase-interface.（4）In a high-T and high-A region,there is no longer a linear relationship between InQ-1 and T-1,whereas the relation Q-1f-n is still satisfied,where n increases as A increases,andthe damping has a normal amplitude effect but one which is weaker than that in the case（3）.The damping maybe attributed to another kind of nonlinear relaxation between phase-interfaces.

关键词： non-linear relaxations Al-Zn alloy damping

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Quantitative amendment of high-field ^(13)C NMR spectra of coals

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Chinese Science Bulletin 1997年第10期42卷 807-809页

作者： YANG Baolian, LI Liyun and YE ChaohuiLaboratory of Magnetic Resonance and atomic and molecular Physics, Wuhan institute of Physics and Mathematics, Chinese Academy of sciences, Wuhan 430071, china Laboratory of Magnetic Resonance and atomic and molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China

HIGH-RESOLUTION solid state 13C NMR spectroscopy has been a useful tool for the study of *** the use of cross polarization（CP）,magic angle spinning（MAS）and protonhigh-power decoupling（HPD）techniques,high-resolution solid state 13C NMR spectra ofcoals can be obtained and the coal aromaticity（fa）can be measured *** aromaticityis defined as the ratio of aromatic carbon atoms to the total carbon atoms in *** pa-

关键词： 13C NMR coal structure quantitative amendment.

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