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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,{2., chengdu 610065, 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,{2., chengdu 610065, 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.

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,{2., china 2. college of Chemical Engineering, sichuan university,{2., china 3. Mianyang Teacher抯 college, Mianyang 62.000, china 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 Engineering 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.

Diamond synthesis from a system of chromium-carbide andNi_(70)Mn_(2.)Co_5 alloy

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Chinese Science Bulletin 1998年第24期43卷 2063-2066页

作者： LI Liangbin 1, JIANG Jinchun 1, HONG Shiming 1, ZHONG Yumao 2.and ZHANG Xinyuan 2.1. Institute of Applied physics, sichuan Union {2., chengdu 610065, china 2. Center for Analysis and Test, sichuan Union {2., chengdu 610065, china Institute of Applied physics Sichuan Union University Chengdu China Center for Analysis and Test Sichuan Union University Chengdu China

In order to ascertain the mechanism of interaction between carbide and metallic catalyst and formation of diamond under high pressure and high temperature, and find a new method to synthesize diamond with special properties, it is necessary to investigate the reaction behavior of different carbides and metallic solvent_catalysts under high pressure and high temperature. A system of Cr-3C-2.powder and Ni 70Mn 2.Co 5 alloy in weight ratio of 1∶6 was treated under 6 0 GPa and 1 500℃ for 2., 30 or 60 min respectively. X_ray diffraction of the samples indicated the Cr 3C 2.decomposed partially after high pressure and temperature treatment, and Cr 7C 3, Cr and diamond formed respectively. There was not any trace of graphite in the samples. The result suggested that the separated carbon atoms could form diamond directly without conversion process of graphite into diamond. The observation of SEI, WDX and EDX also showed that diamond crystals were synthesized in the system, which have perfect surfaces and shapes, with the average grain size of about 40 μm. The properties of the crystals are being investigated.

关键词： chromium_carbide high pressure synthesis diamond.

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

Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3 & QI Xinhua31. Institute of Nuclear physics and Chemistry, china Academy of Engineering physics, Mianyang 62.900, china 2. Department of physics, Peking university, Beijing 100871, china 3. Institute of Atomic and Molecular physics, sichuan university, chengdu 610065, china Institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang China Department of physics Peking university Beijing China Institute of Atomic and Molecular physics Sichuan University Chengdu China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of 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, sichuan university,{2., 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.

Accurate studies on dissociation energies of diatomic molecules

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 611-621页

作者： SUN WeiGuo1, FAN QunChao1 & REN WeiYi1,2.1 Institute of physics, sichuan university,{2., china 2.Institute of Theoretical physics, Xihua Normal university, Nanchong 637002. china Institute of physics Sichuan University Chengdu China Institute of Theoretical physics Xihua Normal University Nanchong China

The molecular dissociation energies of some electronic states of hydride and N2.molecules were studied using a parameter-free analytical formula suggested in this study and the algebraic method (AM) proposed recently. The results show that the accurate AM dissociation energies DeAM agree excellently with experimental dissociation energies Deexpt, and that the dissociation energy of an electronic state such as the 2.Δg state of 7Li2.whose experimental value is not available can be predicted using the new formula.

关键词： algebraic method, diatomic molecule, vibrational energy, dissociation energy

APPLYING PPE MODEL BASED ON RAGA TO CLASSIFYAND EVALUATE SOIL GRADE

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Chinese Geographical Science 2002年第2期12卷 136-141页

作者： FU Qiang1,2. LU Tie guang2. FU Hong2.1. college of Hydraulic Power, sichuan university,{2., P.R.china 2. Northeast Agricultural university, Harbin 150030, P. R. china) college of Hydraulic Power Sichuan University Chengdu P. R. China Northeast Agricultural university Harbin P. R. China

The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result can be influenced by artificial factors. The essentials of fuzzy synthetically judge is to handle the data of high dimension. That is to reducing the dimension number. The weight matrix in fuzzy theory is corresponding to low dimension projection value of each index. But we can′t define whether the weight matrix given by experts is the best projection value or not. So, the authors apply a new technique of falling dimension named projection pursuit to soil study, through using the improved real coding based accelerating genetic algorithm to optimize the projection direction. Thus, it can transfer multi dimension data into one dimension data, through searching for the optimum projection direction to realize the soil classification and its grade evaluation. The method can avoid the artificial disturbance, and acquire preferably effect. Thus, the paper provides a new method to the research of soil classification and grade evaluation.

关键词： RAGA PPE soil classification soil evaluation

CHARACTERISTIC ANALYSIS OF THE PLUNGING OF TURBIDITY CURRENTS

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Journal of Hydrodynamics 2010年第2期22卷 274-282页

作者： AN Rui-dong LI Jia State key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China college of Water Recourse and Hydropower Sichuan University Chengdu 610065 China

Turbidity currents are flows driven by suspended sediment of flood-induced turbid river water with excess *** currents are often the governing factor in reservoir sedimentation by transporting fine materials over long distances and delivering the majority of deposition,which thus reduces the storage ***,the design and operation of a reservoir requires an accurate prediction of its occurrence condition and plunging position,which is the objective of the present *** article presents a verified algebraic slip mixture model including momentum,continuity and algebraic velocity expressions to simulate 2.D turbidity *** experiments in a multiphase flume were carried *** number,sediment concentration and densimetric Froude number were used as parameters in the occurrence condition *** plunging of turbidity currents may produce reflux and backflow due to the diving flow at the surface of the clear *** similar experimental results were also obtained by PIV measurements

关键词： turbidity current plunge suspend sediment algebraic slip mixture model densimetric Froude number