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A study of the dynamical-fluctuation property inside jets in e^+e^-collisions

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Science China(Physics,Mechanics & Astronomy) 2003年第3期46卷 268-283页

作者：陈刚张昆实刘连寿 Institute of Particle Physics Huazhong Normal UniversityWuhan 430079China Jingzhou Teacher's CollegeJingzhou 434020China Institute of Particle Physics Huazhong Normal UniversityWuhan 430079China

A study of the dynamical-fluctuation property of 2-jet events is carried out. It is found that the dynamical fluctuations of the hadronic system inside 2-jet events change with the variation of the cut parameter ycut. There is a transition point, where the dynamical fluctuations in these systems are circular in the transverse plane; and are elliptical in the longitudinal-transverse planes. It is shown that this transition point corresponds to the scale of visible jets. Meanwhile, the dynamical fluctuation properties inside a single-jet in 2-jet and 3-jet events are compared. The dynamical fluctuations inside quark- and gluon-jets are found to be qualitatively different. A scale for the 'visible gluon jet' production is thus obtained.

关键词： high energy multi-production, dynamical fluctuation, gluon-jets, quark-jets, scale.

Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China

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Science China Earth Sciences 2004年第12期47卷 1065-1075页

作者： YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100029,China 2.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China Chinese Academy of Sciences Institute of Tibetan Plateau Research Beijing China Chinese Academy of Sciences Cold and Arid Regions Environmental and Engineering Research Institute Lanzhou China

Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in China is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in China has an important impact on the water resource of the arid regions in Northwest China. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest China. In the Tarim River basin, the increase of river runoff is higher than 5.5%.

关键词： High Asia, glacial fluctuation, impact on water resource.

Stochastic bi-resonance induced by external noise for Ca^2+ signaling in hepatocytes

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Science China Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2,HOU Zhonghuai1 & XIN Houwen1 1.Department of Chemical Physics,University of Science and Technology of China,Hefei 230026,China 2.College of Physics and Electronic Information,Anhui Normal University,Wuhu 241000,China Department of Chemical Physics University of Science and Technology of China Hefei China College of Physics and Electronic Information Anhui Normal University Wuhu China

The influence of external noise on intracellular Ca2+ oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2+ oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Stochastic bi-resonance in non-isothermal carbon monoxide catalytic oxidation system

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Science China Chemistry 2007年第6期50卷 731-736页

作者： GONG YuBing1, XU Bo1, HAN JiQu2, XU XiuWei1 & LIU ShengDian1 1 School of Physics & Electronic Engineering, Ludong University, Yantai 264025, China 2 School of Photoelectricity Information Science Technology, Yantai University, Yantai 264005, China School of Physics & Electronic Engineering Ludong University Yantai China School of Photoelectricity Information Science Technology Yantai University Yantai China

The Pt(110)/CO+O2 system subject to reaction heat, heat conduction and radiative heat transfer is non-isothermal and its temperature varies in time and space. In this paper, taking support temperature (ST) as the control parameter, the effect of the ST fluctuations in the oscillatory dynamics of the non-isothermal Pt(110)/CO+O2 system is numerically studied. It is found that the ST fluctuations may induce stochastic oscillations and the oscillations exhibit stochastic bi-resonance (SBR) with the change of the strength or correlation time of the fluctuations. This result shows that the temperature fluctuations may enhance the chemical reaction oscillations. Moreover, the system can selectively and repeatedly employ the temperature fluctuations to enhance its reaction oscillations. It is also shown when the distance of the ST temperature to the oscillatory region increases a little, the effect of the temperature fluctuations would obviously weaken.

关键词： non-isothermal system of CO catalytic oxidation, reaction rate oscillation, temperature fluctuation, stochastic bi-resonance

The Squeezing Effect in a Mesoscopic RLC Circuit

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Communications in Theoretical Physics 2002年第5期38卷 611-614页

作者： JI Ying-Hua LUO Hai-Mei LEI Min-Sheng Department of Physics Jiangxi Normal University Nanchang 330027 China Department of Physics Jiangxi Normal University Nanchang 330027 China Department of Physics Jiangxi Normal University Nanchang 330027 China

Using the path integral method we derive quantum wave function and quantum fluctuations of charge andcurrent in the mesoscopic RLC circuit. We find that the quantum fluctuation of charge decreases with time, oppositely,the quantum fluctuation of current increases with time monotonously. Therefore there is a squeezing effect in the *** some more charge devices are used in the mesoscopic-damped circuit, the quantum noise can be reduced. We also findthat uncertainty relation of charge and current periodically varies with the period π/2 in the under-damped case.

关键词： dissipative mesoscopic RLC circuit, quantum fluctuation, squeezing effect

Charge fluctuations in Au+Au collisions at RHIC energy

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Science China(Physics,Mechanics & Astronomy) 2003年第5期46卷 535-541页

作者：周代梅萨本豪蔡勖 Institute of Particle Physics Huazhong Normal University Wuhan 430079 China China Institute of Atomic Energy Beijing 102413 China

A hadron and string cascade model, JPCIAE, together with the corresponding Monte Carlo event generator, has been employed in this paper to investigate further the charge fluctuations in Au+Au collisions at √ s nn = 130 GeV. The default JPCIAE calculations are in good agreement with PHENIX and STAR data. We found that the thermal predictions for the π gas, the resonance π gas and quark matter deviate, respectively. from the corresponding dynamical simulations from the JPCIAE model. The discrepancies were also found between the π charge fluctuations and the charge fluctuations of all species of hadrons. However the charge fluctuations for “π from ρ and ω decay” and for all the hadrons from resonance decay are close to each other, indicating the correlation between positively and negatively charged hardrons is not sensitive to the species of hardrons. This work shows further that it is questionable to use the charge fluctuations as a signature of QGP.

关键词： relativistic heavy-ion collision, charge fluctuation, thermal model, JPCIAE model.