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Phase Transition for Dielectric Breakdown Model

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 201-206页

作者： Fuxuan CHANG &Houqiang LI &De L IU &L ibin L IN (Department of physics. Open laboratory of Radiation physics and Technology,sichuan university,{4.,6 1 0 0 6 4.china) 1The paper was received on Nov. 2 0 ,1997 Department of physics Open laboratory of Radiation Physics and Technology Sichuan University Chengdu 610064 China

In this paper,the phase transition for DBM whenηvaries is investigated by using real- space renormalization-group method. The resultdemonstrates that there are phase transitions for almost all the value ofη,and we f... 详细信息

关键词： DBM phase transition renormalization-group

Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong physics Department, college of Information Science and Engineering, Ocean university of china, Qingdao 266100, Shandong, china [a] physics Department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5 meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3P, TIP4., MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4., and TIP3P potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

LOW ORDER NONCONFORMING RECTANGULAR FINITE ELEMENT METHODS FOR DARCY-STOKES PROBLEMS

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Journal of Computational Mathematics 2009年第Z1期 400-424页

作者： Shiquan Zhang School of Mathematics,sichuan university,chengdu 610064.china Xiaoping Xie Yangtze Center of Mathematics and School of Mathematics,sichuan university,chengdu 610064.china Yumei Chen School of Mathematics,sichuan university,chengdu 610064.china college of Mathematics and Information,china West Normal university,Nanchong 637002,china

In this paper,we consider lower order rectangular finite element methods for the sin-gularly perturbed Stokes *** model problem reduces to a linear Stokes problemwhen the perturbation parameter is large and degenerates to a mixed formulation of Pois-son’s equation as the perturbation parameter tends to *** propose two 2D andtwo 3D nonconforming rectangular finite elements,and derive robust discretization *** experiments are carried out to verify the theoretical results.

关键词： Darcy-Stokes problem Finite element Uniformly stable

Research on Water Resources Conservation of Mountain River Based on the Concept of Region Partition

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Journal of Mountain Science 2011年第4期8卷 582-591页

作者： LIU Yubang TAO Qingyu LIANG Chuan WU Yong State Key Laboratory of Geohazard Prevention and Geoenvironment Protection chengdu university of Technology Chengdu 61o059 China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource & Hydropower Sichuan University Chengdu 61oo65 China Academic Journal Center of chengdu university of Technology Chengdu 61oo59 China

Presently concepts and methods related to water resources conservation of mountain rivers are seriously insufficient,and its level is far from being adaptable to the development of a harmonious *** mountain ecosystems play a key role in water resources conservation of mountain rivers,and the characteristics of mountain ecosystems and hydrologic features of mountain river follow strong temporal and spatial distribution,partition theory can be applied to the water resources conservation of mountain *** theory observes the following partition principles:regional relativity,spatial continuity,integralcounty,meeting management needs,hierarchical principle,and comparability *** it lays equal emphasis on both water resources conservation and environmental protection,on both water quality conservation and water quantity protection,on the combination of water features,water cycle and water *** the partition methods,index method and map superposition method will be applied in region *** example of region partition of water resources conservation in the upper reaches of the Yangtze River shows that the partition theory is practicable in water resources conservation of mountain rivers,and it provides a platform for future study in water resources conservation.

关键词： Water resources conservation Mountain river Region partition Mountain ecosystems

X-ray spectra induced in highly charged 4.Ar^q+ interacting with Au surface

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2, XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3, ZHAO Yongtao1, LI Fuli4. ZHANG Yinping1, CUI Ying3, ZHANG Hongqiang3, XU Xu3, SHAO Jianxiong3 & ZHAN Wenlong11. Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2. Department of physics, Xianyang Normal university, Xianyang 712000, china 3. Department of Modern physics, Lanzhou university, Lanzhou 730000, china 4. Department of Applied physics, Xi’an Jiaotong university, Xi’an 71004., china 1. Institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China 2. Department of physics Xianyang Normal University Xianyang 712000 China 3. Department of Modern physics Lanzhou University Lanzhou 730000 China 4. Department of Applied physics Xi’an Jiaotong University Xi’an 710049 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 4.Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2 in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

A Numerical Stress-strain Response Model of All Grades of Concretes under Uniaxial Compression

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Journal of Wuhan university of Technology(Materials Science) 2006年第3期21卷 149-152页

作者：王勇威 college of Water Resource & Hydropower Sichuan UniversityChengdu 610065China

An important problem facing stress-strain response modeling of concrete is the complexity of the compressive strength grades. 21 groups of speeimens with different cubic compressive strength （56.3- 164.9 MPa ） hate beets numerically analyzed. Using only the compressive strength, a stress-strain response model of different concrete grade was established. The numerical simulation model not only qualitatively reproduces the relationship of uniaxial compressive strength, peak value stress and cubic compressive strength, but realizes the consistence of the ascending branch of stress-strain cunts with different strength grades by introducing the correction coefficient k. The results indicate k increases gradually from 0 to approximate 1 with the increase of the compressive strength, corresponding to the transition from the paracurve to straight line branch in stress-strain curves. When k is 0, the madel is identical to the Hognestad equation. A good agreement with the experiment data was obtained.

关键词： high-strength concrete stress-strain response mechanical property

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2 1. Institute of Laser physics and Chemistry, sichuan university, chengdu 610064. china 2. Department of physics, Luoyang Normal college, Luoyang 4.1022, china 3. State Key Laboratory of Laser Technology, Huazhong university of Science and Technology, Wuhan 4.0074. china Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2003 1. Institute of Laser physics and Chemistry Sichuan University 610064 Chengdu China 2. State Key Laboratory of Laser Technology Huazhong University of Science and Technology 430074 Wuhan China 3. Department of physics Luoyang Normal College 471022 Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Gas-phase photocatalytic oxidation of benzene over titanium dioxide loaded on Bi_(12)TiO_(20)

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Chinese Chemical Letters 2007年第2期18卷 241-243页

作者： Tao Lin, Zhan Pi, Mao Chu Gong, Jun Bo Zhong, Jian Li Wang, Yao Qiang Chen college of Chemistry, sichuan university, chengdu 610064. china college of Chemistry Sichuan University Chengdu 610064 China

TiO2 was prepared by sol-gel method using tetrabutyl titanate as precursor. TiO2 was loaded on Bi12TiO20. The photocatalyst with different TiO2 loading was calcined at 723 K. The photocatalytic activity of decomposition gaseous benzene was investigated in a batch reactor. The prepared photocatalyst was characterized by UV-vis diffuse reflectance. The result showed that TiO2/Bi12TiO20 absorbed much more ultraviolet light than Ti02 in the ultraviolet light region and showed red shift. The results indicated that the prepared photocatalyst can greatly promote the photocatalytic activity. The 2.0% TiO2/Bi12TiO20 system exhibited the highest photocatalytic activity.

关键词： Titanium Bi_(12)TiO_(20) Benzene Photocatalytic oxidation

A multidimensional subdiffusion model:An arbitrage-free market

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Chinese physics B 2012年第12期21卷 561-567页

作者：李国华张红罗懋康 college of Mathematics Sichuan University

To capture the subdiffusive characteristics of financial markets, the subordinated process, directed by the inverse α-stale subordinator Sα （t） for 0 〈 α〈 1, has been employed as the model of asset prices. In this article, we introduce a multidimensional subdiffusion model that has a bond and K correlated stocks. The stock price process is a multidimen- sional subdiffusion process directed by the inverse a-stable subordinator. This model describes the period of stagnation for each stock and the behavior of the dependency between multiple stocks. Moreover, we derive the multidimensional fractional backward Kolmogorov equation for the subordinated process using the Laplace transform technique. Finally, using a martingale approach, we prove that the multidimensional subdiffusion model is arbitrage-free, and also gives an arbitrage-free pricing rule for contingent claims associated with the martingale measure.

关键词： subordination arbitrage-free contingent claim valuation fractional backward Kol-mogorov equation