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Chinese physics B 2010年第2期19卷 13-18页

作者：关剑月吴枝喜黄子罡汪映海 Institute of Theoretical physics Lanzhou University department of physics Ume University90187 UmeSweden

An evolutionary prisoner＇s dilemma game is investigated on two-layered complex networks respectively representing interaction and learning networks in one and two dimensions. A parameter q is introduced to denote the correlation degree between the two-layered networks. Using Monte Carlo simulations we studied the effects of the correlation degree on cooperative behaviour and found that the cooperator density nontrivially changes with q for different payoff parameter values depending on the detailed strategy updating and network dimension. An explanation for the obtained results is provided.

关键词： prisoner's dilemma game two-layered complex networks cooperation

Another Conserved Quantity by Mei Symmetry of Tzénoff Equation for Non-Holonomic Systems

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Chinese physics Letters 2010年第3期27卷 37-39页

作者：郑世旺解加芳王建波陈向炜 department of physics and Information engineering Shangqiu Teachers College Shangqiu 476000 College of Science North China University of Technology Beijing 100144

As a direct result of Mei symmetry of the Ténoff equation for non-holonomic mechanical systems, another conserved quantity is studied. The expression and the determining equations of the above conserved quantity are also presented. Using this method, it is easier to find out conserved quantity than ever. In the last, an example is presented to illustrate applications of the new results.

关键词： Mathematical physics

Noise effect in metabolic networks

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Chinese physics B 2009年第12期18卷 5544-5551页

作者：李政言谢正伟陈同欧阳颀 Center for Theoretical Biology and State Key Laboratory for Mesoscopic PhysicsDepartment of PhysicsPeking University

Constraint-based models such as flux balance analysis （FBA） are a powerful tool to study biological metabolic networks. Under the hypothesis that cells operate at an optimal growth rate as the result of evolution and natural selection, this model successfully predicts most cellular behaviours in growth rate. However, the model ignores the fact that cells can change their cellular metabolic states during evolution, leaving optimal metabolic states unstable. Here, we consider all the cellular processes that change metabolic states into a single term‘noise＇, and assume that cells change metabolic states by randomly walking in feasible solution space. By simulating a state of a cell randomly walking in the constrained solution space of metabolic networks, we found that in a noisy environment cells in optimal states tend to travel away from these points. On considering the competition between the noise effect and the growth effect in cell evolution, we found that there exists a trade-off between these two effects. As a result, the population of the cells contains different cellular metabolic states, and the population growth rate is at suboptimal states.

关键词： noise metabolic networks flux balance analysis

Giant Magneto-Impedance Effect in As-Deposited Multilayered Amorphous Films

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Chinese physics Letters 1999年第6期16卷 452-454页

作者： XIAO Shu-qin LIU De-zhen LIU Yi-hua DAI You-yong ZHANG Lin MEI Liang-mo department of physics Shandong UniversityJi'nan 250100 College of Materials Science and engineering Shandong University of TechnologyJi'nan 250014

Giant magneto-impedance effects have been observed in as-deposited amorphous FeCuNbSiB/Cu/FeCuNbSiB and FeCuNbSiB/SiO_(2)/Ag/SiO_(2)/FeCuNbSiB multilayered *** films were deposited onto Si substrates by radio frequency *** FeCuNbSiB/Cu/FeCuNbSiB films,maximum giant magneto-impedance ratios as large as 32%and 11%were obtained at 13 MHz in the longitudinal and transverse fields,*** FeCuNbSiB/SiO_(2)/Ag/SiO_(2)/FeCuNbSiB films,the maximum giant magneto-impedance ratios were 47%and 57%at the same frequency for the two cases,which are much larger than those obtained in the annealed single layer Hlms.

关键词： impedance amorphous transverse

DRIFT MOTION OF FREE-ROTOR GYROSCOPE WITH RADIAL MASS-UNBALANCE

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Applied Mathematics and Mechanics(English Edition) 2004年第7期25卷 786-791页

作者：刘延柱薛纭 department of engineering Mechanics department of Mechanical engineering

The motion of a rigid body about fixed point with small radial mass-unbalance in homogeneous gravitational field was discussed. The dynamical equations described by state variables of the body were established, and approximate analytical solutions for a spinning body with high speed were obtained by use of the average method. The influence of the radial mass-unbalance of the rotor to the precession character of a free-rotor gyroscope was analyzed. And a physical explanation of the drift phenomenon of the gyro was given. An applicable formula of gyro's constant drift in analytical form was obtained, which is perfectly coincident with the numerical calculation.

关键词： dynamics of rigid body drift of gyroscope average method

Photorefractive Effect in Poly (N-Vinylcarbazole) Composite with Fullerene

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Chinese physics Letters 1997年第11期14卷 842-844页

作者： CHEN Zhi-jian XU Li-fang HUANG Zhi-wen GONG Qi-huang ZHANG Zhi-jie CHEN Yi-wang CHEN Hui-ying department of physics Mesoscope Physics LaboratoryPeking UniversityBeijing 100871 department of Chemistry Peking UniversityBeijing 100871

The photorefractive effect was observed in poly(N-vinylcarbazole)composite films doped with electro-optic chromophore 2,5-dimetly-4(p-nitrophenylazo)anisole,plasticizer N-ethylcarbazole and different content fullerene *** two-beam coupling experiment was performed by using a cw He-Ne laser at *** two-beam-coupling gain coefficient as higher as 140cm^(-1) was measured at poling dc electric field of 76V/μm and it was also found to be relied on the content of photosensitizer C60.

关键词： carbazole coupling content

Precise Determination of Period of a Torsion Pendulum in Measurement of Gravitational Constant

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Chinese physics Letters 2005年第9期22卷 2169-2172页

作者：罗杰王典洪刘祺邵成刚 Faculty of Mechanical and Electronic engineering China University of Geosciences Wuhan 430074 department of physics Huazhong University of Science and Technology Wuhan 430074

The period of a torsion pendulum would vary under the disturbances of environmental noise factors. In order to subtract the period of the pendulum from external influence, we employ the correlation method to determine the period with a high precision. Theoretical analysis shows that the relative precision is improved to be proportional to 1/m^3/2 with the number of the period m, compared with the conventional statistical mean that is proportional to 1/m^1/2, which is significant for the determination of gravitational constant with the swing time method.

关键词： PHYSICAL OSCILLATOR FITTING METHOD

Influence of intermittently etching on quality of CVD diamond thin films

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中国有色金属学会会刊：英文版 2006年第B01期16卷 321-323页

作者：杨侃诚夏义本王林军刘建敏苏青峰徐闰彭鸿雁史伟民 School of Materials Science and engineering Shanghai UniversityShanghai 200072China department of physics Mudanjiang Normal CollegeMudanjiang 157012China

A new method, called growing-etching repetitional process based on hot filament chemical vapor deposition, was proposed to improve the quality of diamond film. During the deposition carbon source was intermittently closed letting hydrogen etch the surface of the diamond film from time to time. In order to find whether it is helpful to the films’ quality, a series of experiments were done. The results show that the new method can enhance the orientation of the chemical vapor deposition diamond films, reduce the graphite phase and increase the film’s surface resistivity.

关键词：金刚石薄膜 HFCVD法断续蚀刻质量

Modified-PVK-based Photorefractive Three-Component Low-T_(g) Composites

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Chinese physics Letters 1999年第5期16卷 353-355页

作者： WANG Feng CHEN Zhi-jian GONG Qi-huang CHEN Yi-wang CHEN Hui-ying department of physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871 department of Chemistry Peking UniversityBeijing 100871

Two modified poly(N-carbazole),poly(2-carbazolylethyl methacrylate)(PCEMA)and poly(3-carbazolylpropyl methacrylate)(PCPMA),were *** with electro-optic(EO)chromophore 1-n-butoxyl-2,5-dimethyl-4-(4'-nitrophenylazo)benzene and the photosensitizer 2,4,7-trinitro-9-fluorenone,the EO response and photore-fractive(PR)effect were studied *** to the shorter spacer between the carbazolyl and the main-chain and thus a higher glass-transition-temperature T_(g),PCEMA-based composite exhibited an effective EO coefficient as only a quarter as that in PCPMA-based ***,a slight higher two-beam coupling coefficient and much faster PR response were observed in the *** was suggested that both the spacer length and the polymerization degree changed the T_(g) and the number density of traps,which decided the EO and PR responses.

关键词： coefficient faster shorter

Response Time Characteristics and Holographic Gratings in an Azo-Dye Doped Photorefractive Polymeric Composite

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Chinese physics Letters 1998年第5期15卷 351-353页

Theoretical and experimental investigation on the applied electric field-and intensity-dependent photorefractive response in a photorefractive polymeric composite is *** decay time constant and the corresponding grating-amplitude for the composite consisting of 1-n-butoxy1-2,5-dimethy1-4-(4’-nitrophenylazo)benzene:poly(N-vinylcarbazole):2,4,7-trinitro-9-fluorenone with a weight ratio 44:55:1 were *** results revealed that there existed two gratings simultaneously,one was caused by the photorefractive effect,and the other was contributed from the photo-isomerization *** dynamic process for the photorefractive grating was explained with a modified band transport model.

关键词： Photorefractive composite grating