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Tunneling Through Black Rings

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Communications in Theoretical physics 2007年第5期47卷 835-842页

作者： ZHAO Liu department of physics,nankai university,tianjin 300071,china department of physics Nankai University Tianjin 300071 China

Hawking radiation of black ring solutions to 5-dimensional Einstein-Maxwell-dilaton theory is analyzedby use of the Parikh-Wilczek tunneling *** get the correct tunneling amplitude and emission rate,we adoptand develop the Angheben-Nadalini-Vanzo-Zerbini covariant approach to cover the effects of rotation and electronicdischarge all at once,and the effect of back reaction is also taken into *** constitutes a unified approach tothe tunneling *** the first law of thermodynamics for black rings holds,the emission rate is proportionalto the exponential of the change of Bekenstein-Hawking *** calculation for black ring temperatures agreesexactly with the results obtained via the classical surface gravity method and the quasi-local formalism.

关键词： black ring radiation tunneling method

Quantum Entanglement of Two Flux Qubits Induced by an Auxiliary SQUID

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Communications in Theoretical physics 2007年第12期48卷 1003-1008页

作者： SHI Tao SONG Zhi department of physics,nankai university,tianjin 300071,china department of physics Nankai University Tianjin 300071 China

We revisit a theoretical scheme to create quantum entanglement of two three-level superconducting quantuminterference devices (SQUIDs) with the help of an auxiliary *** this scenario,two three-level systems are coupledto a quantized cavity field and a classical external field and thus form dark *** quantum entanglement can beproduced by a quantum measurement on the auxiliary *** investigation emphasizes the quantum effect of theauxiliary *** the experimental feasibility and accessibility of the scheme,we calculate the time evolution of thewhole system including the auxiliary *** ensure the efficiency of generating quantum entanglement,relationsbetween the measurement time and dominate parameters of the system are analyzed according to detailed calculations.

关键词： superconducting quantum interference device entangled state quantum information dark state

Nonlinear Dynamical Behavior in BS Evolution Model Based on Small-World Network Added with Nonlinear Preference

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Communications in Theoretical physics 2007年第7期48卷 137-142页

作者： ZHANG Ying-Yue YANG Qiu-Ying CheN Tian-Lun department of physics,nankai university,tianjin 300071,china department of physics Nankai University Tianjin 300071 China

We introduce a modified small-world network adding new links with nonlinearly preferential connectioninstead of adding randomly,then we apply Bak-Sneppen(BS)evolution model on this *** study severalimportant structural properties of our network such as the distribution of link-degree,the maximum link-degree,and thegth of the shortest *** further argue several dynamical characteristics of the model such as the important criticalvalue f_c,the f_0 avalanche,and the mutating condition,and find that those characteristics show panticular behaviors.

关键词： power-law behavior small-world network evolution model nonlinear preference

Discussion of Some Problems About Nonlinear Time Series Prediction Using v-Support Vector Machine

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Communications in Theoretical physics 2007年第7期48卷 117-124页

作者： GAO Cheng-Feng CheN Tian-Lun NAN Tian-Shi department of physics,nankai university,tianjin 300071,china department of physics Nankai University Tianjin 300071 China

Some problems in using v-support vector machine(v-SVM)for the prediction of nonlinear time series *** problems include selection of various net parameters,which affect the performance of prediction,mixtureof kernels,and decomposition cooperation linear programming v-SVM regression,which result in improvements of *** simulations in the prediction of nonlinear time series produced by Mackey-Glass equation andLorenz equation provide some improved results.

关键词： v-SVM nonlinear time series prediction

Inherent mechanism of breakdown in laminar-turbulent transition of plane channel flows

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 228-236页

作者： LUO Jisheng, WANG Xinjun & ZHOU heng department of Mechanics, tianjin university Liu-Hui Center of Mathematics, nankai and tianjin university, tianjin 300071, china department of Mechanics Tianjin University Tianjin China Liu-Hui Center of Mathematics Nankai and Tianjin University Tianjin China

Laminar-turbulent transition is an old yet unsolved problem. Notwithstanding the great effort made, there is an important question that seems not to have been addressed yet, that is, what is the inherent mechanism of breakdown that eventually leads to transition? The conventional idea is that the transition starts from the amplification of disturbances, and when the disturbances become larger, higher harmonics will be generated due to nonlinear effect, making the flow more and more complicated, and finally turbulent. Though the scenario seems clear, yet there is a missing link, that is, what happens in the breakdown process. here we show by analyzing the results from direct numerical simulations that the change of stability characteristics of the mean flow profile plays a key role in the breakdown process.

关键词： laminar-turbulent transition, breakdown, plane channel flow.

Phenomenological Analysis of Binding Energies of ■ Hypernuclei

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Chinese journal of nuclear physics 1997年第1期19卷 6-11页

作者： Cai Chonghai Ning Pingzhi department of physics,nankai university,Tiaujin 300071 南开大学物理系天津

The ground-state(GS)binding energies of the■hyperon in a few known■hyper-nuclei are calculated by solving Schr■dinger and Dirac equations with phenomenological■nu-cleus potential of Woods-Saxon *** calculated binding energies are in good agreementwith the experimental *** optimal well depth of■-nucleus potential is extracted:U■=23.9 MeV.

关键词： ■ hypernucleus ■nucleus potential Binding energy Dirac equation

Wave-packet method for instability of three-dimensionalboundary layer of swept wing

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Chinese Science Bulletin 1998年第6期43卷 461-464页

作者： ZHAO Gengfu department of physics, tianjin university, tianjin 300072, china department of physics Tianjin University Tianjin China

A wave-packet method is proposed to study evolution the behavior of disturbances in 3-D boundary layer on a swept plate. It is proved that the constant-phase lines are equivalent to the streaks observed in flow-visual... 详细信息

关键词： swept plate wave packet structure of streaks.

Engineering oxygen vacancies on Tb-doped ceria supported Pt catalyst for hydrogen production through steam reforming of long-chain hydrocarbon fuels

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Chinese Journal of Chemical Engineering 2024年第4期68卷 181-192页

作者： Zhourong Xiao Changxuan Zhang Peng Li Desong Wang Xiangwen Zhang Li Wang Jijun Zou guozhu Li State Key Laboratory of Metastable Materials Science and Technology(MMST) Hebei Key Laboratory of Applied ChemistryCollege of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Steam reforming of long-chain hydrocarbon fuels for hydrogen production has received great attention for thermal management of the hypersonic vehicle and fuel-cell *** this work,Pt catalysts supported on CeO_(2)and Tb-doped CeO_(2)were prepared by a precipitation *** physical structure and chemical properties of the as-prepared catalysts were characterized by powder X-ray diffraction,scanning electron microscopy,transmission electron microscopy,Raman spectroscopy,H_(2)temperature programmed reduction,and X-ray photoelectron *** results show that Tb-doped CeO_(2)supported Pt possesses abundant surface oxygen vacancies,good inhibition of ceria sintering,and strong metal-support interaction compared with CeO_(2)supported *** catalytic performance of hydrogen production via steam reforming of long-chain hydrocarbon fuels(n-dodecane)was *** with 2Pt/CeO_(2),2Pt/Ce_(0.9)Tb_(0.1)O_(2),and 2Pt/Ce_(0.5)Tb_(0.5)O_(2),the 2Pt/Ce_(0.7)Tb_(0.3)O_(2)has higher activity and stability for hydrogen production,on which the conversion of n-dodecane was maintained at about 53.2%after 600 min reaction under 700℃at liquid space velocity of 9 ml·g^(-1)·h^(-1).2Pt/CeO_(2)rapidly deactivated,the conversion of n-dodecane was reduced to only 41.6%after 600 min.

关键词： Steam reforming n-Dodecane Hydrogen production Pt-based catalyst Oxygen vacancy CeO_(2)

Views on “Principle of limitation of physical quantities and cyclic universe”

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1772-1774页

作者： LI LianGang department of physics,School of Sciences,tianjin university,tianjin 300072,china department of physics School of Sciences Tianjin University Tianjin China

This paper presents an analysis of a paper entitled "Principle of limitation of physical quantities and cyclic universe" and proposes different results for some formulae from that *** addition,this paper shows that the principle of limits coupling may lead to an approximation of current theories(i.e.,quantum theory and relativistic theory),which have interesting correlations with the Plank formula and the special theory of relativity.

关键词： principle of limitation of physical quantities limits coupling formulae Plank formula theory of relativity