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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 61.065,{2. 2. college of chemical engineering, sichuan university, chengdu 61.065,{2. 3. Mianyang Teacher抯 college, Mianyang 62.000,{2. Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) Institute of Physics Sichuan University Chengdu China Mianyang Teacher's college Mianyang China college of chemical {2. Sichuan University 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 A2. 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 A2. 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.

Energy-Based Prediction of Low Cycle Fatigue Life of High-Strength Structural Steel

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Journal of Iron and Steel Research International 2012年第10期19卷 47-53页

作者： LUO Yun-rong1,2. HUANG Chong-xiang1, GUO Yi2. WANG Qing-yuan1 (1. college of Architecture and Environment, sichuan university,{2., sichuan, china 2. college of Mechanical engineering, sichuan university of Science and engineering, Zigong 643000, sichuan, china) college of Architecture lind Environment Sichuan University Chengdu Sichuan China college of Mechanical engineering Sichuan University of Science and Engineering Zigong Sichuan China

Energy-based models for predicting the low-cycle fatigue life of high-strength structural steels are presented. The models are based on energy dissipation during average of cycles, cycles to crack propagation and total cycles to failure. Plastic strain energy per cycle was determined and found as an important characteristic for initiation and propagation of fatigue cracks for high-strength structural steels. Fatigue strain-life curves were generated using plastic energy dissipation per cycle (loop area) and compared with the Coffin-Manson relation. Low cycle fatigue life was found similar from both methods. The material showed Masing-type behavior. The cyclic hysterisis energy per cycle was calculated from cyclic stress-strain parameters. The fracture surfaces of the fatigue samples were characterized by scanning electron microscope and the fracture mechanisms were discussed.

关键词： low cycle fatigue high-strength steel energy-based model fatigue life

Theoretical study on the hydrolysis mechanism of N,N-dimethyl-N′-(2.,3′-dideoxy-3′-thiacytidine)formamidine

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Science china Chemistry 2008年第10期51卷 911-917页

作者： ZHANG Chang1 & XUE Ying2. 1 college of Chemistry and Environment Protection engineering, Southwest {2. for Nationalities, chengdu 610041, china 2.college of Chemistry, sichuan university, chengdu 610064, china college of Chemistry and Environment Protection engineering Southwest University for Nationalities Chengdu China college of Chemistry Sichuan University Chengdu China

The hydrolysis mechanisms of N,N-dimethyl-N′-(2.,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered. In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C—N single bond first (path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d, p) level of theory based on the po-larizable continuum model (CPCM). In water the first mechanism (path A) is also favored.

关键词： N N-dimethyl-N′-(2. 3′-dideoxy-3′-thiacytidine)formamidine hydrolysis solvent effect B3LYP polarizable continuum model

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 {2., sichuan university, chengdu 61.065, china 2. Institute of Theoretical Physics, Xihua Normal university, Nanchong 637002. china 3. Department of Physics, china Oceanography university, Qingdao 2.6003, china 4. college of Physics, sichuan university, chengdu 61.065, china Institute of Physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China college of Physics Sichuan University 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.

Vertical ionization energies of halogen anions in solution

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Science china Chemistry 2010年第6期53卷 1316-1321页

作者： CHENG XueMin,ZHU Quan,WANG XingJian,LI YunKui & LI XiangYuan college of chemical {2.,sichuan university,chengdu 61.065,china college of chemical {2. Sichuan University Chengdu China

Based on the constrained equilibrium state theory,the nonequilibrium solvation energy is derived in the framework of the continuum *** formula for spectral shift and vertical ionization energy are deduced for a single sphere cavity with the point charge *** new model is adopted to investigate the vertical ionization for halogen atomic and molecular anions X(X = Cl,Br,I,Cl2.Br2.I2. in aqueous *** to the calculation using the CCSD-t/aug-cc-pVQZ method in vacuum,our final estimated vertical ionization energies in solution are very close to the experimental observations,while the traditional nonequilibrium solvation theory overestimates these vertical ionization energies.

关键词： vertical ionization energy spectral shift constrained equilibrium state

Encapsulation of inorganic particles by dispersion polymerization through ultrasonic irradiation

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Science china Chemistry 2005年第6期48卷 545-552页

作者： ZHANG Kai1,2. FU Qiang1, HUANG Yuhong2.& ZHOU Dehui2.1. college of Polymer Science and engineering,{2., chengdu 61.065, china 2. Institute of Structure Mechanics, china Academy of engineering Physics, Mianyang 62.900, china college of Polymer Science and engineering Sichuan University Chengdu China Institute of Structure Mechanics China Academy of Engineering Physics Mianyang China

The nano-silica/polystyrene composite particles were prepared and characterized according to the following steps. First, the nano-silica particles were pretreated with surfactants under ultrasonic field. Second, the dispersion polymerization of styrene in a water/ethanol (1/6, weight ratio) medium, with poly(N-vinyl pyrrolidone) (PVP) as stabilizer and 2.2.-azobisizobu- tyronitrile (AIBN) as initiator in the presence of nano-silica particles was initiated with N2.purging through ultrasonic irradiation by taking its advantages of multieffect, i.e. dispersion, crushing, activation, and initiation. Finally, the polymerization kinetics characteristics were studied, and the encapsulation of composite particles was investigated with optical microscope, SEM, TEM, FTIR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

关键词： composite particle, dispersion polymerization, ultrasonic irradiation.

One approach to calculating the solvent reorganization energy of intramolecular electron transfer

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Chinese Science Bulletin 2003年第1期48卷 35-38页

作者： FU Kexiang1,2. LI Xiangyuan1, ZHU Quan1 & LU Shenzhuang1 1. college of chemical {2., sichuan university, chengdu 61.065, china 2. college of Physics, sichuan university, chengdu 610064, china Correspondence should be addressed to Li Xiangyuan (e-mail: xyli@***) college of chemical {2. Sichuan University Chengdu 610065 China college of Physics Sichuan University Chengdu 610064 China

On the basis of the electromagnetic field theory and the spherical cavity approximation, the expressions ofGibbs free energies under equilibrium and non-equilibrium solvation conditions are obtained by solving the electrostatic potential equations with boundary conditions. The surface charges produced by the orientational polarization of equi-librium solvation are taken fixed in the case of non-equilibrium situation, for the slow-response of the orientational polarization to electron transfer of the solvent molecules. Anew expression of solvent reorganization energy has beenobtained and this method is applied to the electron transfer systems, NO+/NO, NO2./NO2. and NO2./NO. The solvent reorganization energies have been evaluated.

关键词：分子内电子传递溶剂重排能定向极化自由能电子极化计算方法

A new grid-associated algorithm in the distributed hydrological model simulations

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Science china(Technological Sciences) 2010年第1期53卷 235-241页

作者： XU Rui1,2.HUANG XiaoXue1,LUO Lin1 & LI ShaoCai3 1 State Key Laboratory of Hydraulics and Mountain River engineering college of Architecture and Environment,{2. university,chengdu 61.065,china 2.college of Electronic engineering,Guilin university of Electronic Technology,Guilin 541004,china 3 college of Life Sciences,{2. university,chengdu 61.065,china State Key Laboratory of Hydraulics and Mountain River engineering college of Architecture and Environment Sichuan University Chengdu China college of Electronic engineering Guilin University of Electronic Technology Guilin China college of Life Sciences Sichuan University Chengdu China

This paper presents a new grid-associated algorithm to improve the performance of a D8 algorithm based distributed hydrological model *** algorithm is based on the well known single-flow D8 algorithm of grid *** algorithm allocates calculation priorities according to the distance between the units and the outlet,then carries out the ergodic computations of the hydrological units according to the priority *** the parallelized algorithm,a standard thread-level shared memory system for parallel programming(OpenMP-Open specifications for Multi Processing) was introduced,and the parallel coding was implemented in C lan-guage.A case study showed that the absolute speed-up ratio of the grid-associated algorithm is 1.64 over the original D8 algorithm,and the linear speed-up ratio of the parallel associated algorithm is 2.42.under 4 *** parallel grid-associated algorithm can be applied to a variety of research fields that use the grid method.

关键词： distributed hydrological model grid-association algorithm OpenMP parallel computing

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2.3 , ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3,5 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , chengdu 610041, sichuan,{2. 2. Graduate university of Chinese Academy of Sciences, Beijing 100049,{2. 3. sichuan Institute of Land Resource Management, chengdu 610041, sichuan ,{2. 4. Department of Resources and Environment Science, sichuan Normal university , chengdu 610061, sichuan,{2. 5. college of Information engineering, chengdu university of Technology, chengdu 610059, sichuan,{2. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of Sciences Beijing China sichuan Institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China college of Information engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2.02. the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.