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Two-photon spectroscopic behaviors and photodynamic effect on the BEL-7402 cancer cells of the new chlorophyll photosensitizer

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Science china Chemistry 2008年第6期51卷 529-538页

作者： ZHAO PeiDe1,2,CHEN Ping1,TANG GuoQing1,LIU JinWei2,LIN Lie1,GUO Peng1,YU Qing2, YAO JianZhong3,MA DongMing4,ZHANG GuiLan1 & CHEN WenJu1 1 Key Laboratory of Optoelectronic Information Science and technology,Ministry of Education,Institute of Modern Optics,Nankai university,tianjin 300071,china 2 department of physics,hebei university of technology,tianjin 300130,china 3 College of Pharmacy,Second Military Medical university,Shanghai 200433,china 4 tianjin College of the Traditional Chinese Medicine,tianjin 300193,china Key Laboratory of Optoelectronic Information Science and technology Ministry of Education Institute of Modern Optics Nankai University Tianjin China department of physics Hebei University of Technology Tianjin China College of Pharmacy Second Military Medical University Shanghai China tianjin College of the Traditional Chinese Medicine Tianjin China

The spectroscopic properties of a new chlorophyll derivate photosensitizer (CDP) are studied under the excitation wavelengths at 800 and 400 nm using femtosecond pulses from a Ti: sapphire laser. The damaging effect of CDP on the BEL-7402 cancer cells is also investigated upon two-photon illumination at 800 nm. The normalized fluorescence spectra of CDP in tetrahydrofuran (THF) show that two-photon and one-photon spectra have the same distributions and the same emission bands (675 nm). The lifetimes of two- and one-photon induced fluorescence of this molecule are of the order of 5.0 ns. By comparing the data it is shown that there is some difference between the two lifetimes, but the difference is less than one nanosecond. The two-photon absorption cross section of the molecule is also measured at 800 nm and estimated as about σ'_2 ≈ 31.5x10^(-50)cm^4·s·photon^(-1). The results of two-photon photodynamic therapy (TPPDT) tests show that CDP can kill all of the tested cancer cells according to the usual Eosine assessment. Our results indicate that the two-photon-induced photophysical, photochemical and photosensitizing processes of CDP may be basically similar to those of one-photon excitation. These behaviors of the sample suggest that one may find other possible methods to estimate some photosensitizers' effects in details such as their distribution in cells and the reactive targets of the sub-cellular parts of some tumor cells via two-photon excitation techniques.

关键词： photosensitizer chlorophyll derivate two-photon fluorescence two-photon absorption cross-section TPPDT BEL-7402 cell

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时空混沌的单向耦合同步

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物理学报 2002年第12期51卷 2702-2706页

作者：张旭沈柯河北工业大学理学院应用物理系长春理工大学理学院物理系长春130022 长春理工大学理学院物理系

以耦合映象格子模型为例 ,提出利用单向耦合驱动时空混沌的同步方案 ,并进行了数值分析 .结果表明 ,适当地选择耦合驱动强度因子和均衡系数 ,两个时空混沌系统可以达到准确同步 .通过计算最大条件Lyapunov指数 ,给出了可实现时空混沌同... 详细信息

以耦合映象格子模型为例 ,提出利用单向耦合驱动时空混沌的同步方案 ,并进行了数值分析 .结果表明 ,适当地选择耦合驱动强度因子和均衡系数 ,两个时空混沌系统可以达到准确同步 .通过计算最大条件Lyapunov指数 ,给出了可实现时空混沌同步的最小耦合强度以及最小耦合强度与系统参数之间的关系曲线 .数值模拟还证明 ,此方法工作鲁棒 .

关键词：时空混沌同步单向耦合最大条件Lyapunov指数数值模拟耦合映象格子模型

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ON THE CONDITIONAL VERSION OFKOLMOGOROV'S THREE-SERIES THEOREM

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Acta Mathematica Scientia 1999年第3期19卷 300-306页

作者：刘国欣 department of Mathematics Hebei University of Technology Tianjin 300130 China

This paper studies the conditional version of Kolmogorov’s three-series theorem, and gets a new extention form of the conditional version. The results here present us an answer to the question when (or where) the conditional version also provide necessary conditions for convergence in dependent cases. Furthermore, some new sufficient conditions are obtained.

关键词： Three-series theorem dependent r.v. ’s predictable local absolute continuity martingale

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Three-Dimensional and Cross-sectional Characteristics of Normal Grain Growth Based on Monte Carlo Simulation

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 129-133,139页

作者： Xiaoyan Song Guoquan Liu(Material Science and Engineering School, university of Science and technology Beijing, Beijing 100083, china)(department of Materials Science and Engineering, hebei university of technology, tianjin 300130, china) Material Science and Engineering School University of Science and Technology Beijing Beijing 100083 China departments of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China

An appropriate Monte Carlo method was developed to simulate the three-dimensional normal grain growth more completely. Comparative investigation on the three-dimensional and the cross-sectional characteristics of normal grain growth was done. It was found that the time exponent of grain growth determined from cross-section exhibits the same rule of increasing slowly with time and approaching the theoretical value n = 0.5 of steadygrain growth as the three-dimensional (3-D) system. From change of the number of grains per unit area with timemeasured in cross-section, the state of 3-D normal grain growth may be predicted. The gtain size distribution incross-section is different from that in 3-D system and can not express the evolution characteristic of the 3-D distribution. Furthermore, there exists statistical connection between the topological parameters in cross-section and thosein three-dimensions.

关键词： Monte Carlo simulation normal grain growth three-dimension cross-section characteristics

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ON THE NONEXISTENCE OF PERIODIC SOLUTIONS FOR LIENARD-TYPE EQUATIONS

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Systems Science and Mathematical Sciences 1999年第2期12卷 184-192页

作者： ZHOU Jin(department of Applied Mathematics, hebei university of technology, tianjin 300130, china) department of Applied Mathematics HebeiUniversity of Technology Tianjin 300130 China

In this paper, we investigate the nonexistence of periodic solutions for Lienardtype equationSome brief and practical sufficient conditions on the nonexistence of periodic solutions aregiven. Our results can be easily applied to the well-known Lienard equation x+f(x) x +g(x) =0, and substantially extend and improve some known results.

关键词： Lienard-type equations Lienard system periodic solutions nonexistence.

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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.

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Large Eddy Simulation of New Vortex Generator Enhancing Heat Exchange of Solar Energy

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湖南大学学报（自然科学版） 2009年第S1期36卷 186-192页

作者： WEN Juan,YANG Li,QI Cheng-ying(department of Thermal Power Engineering,hebei university of technology,tianjin 300401,china) department of Thermal Power Engineering Hebei University of Technology Tianjin 300401 China

This paper put forward a new-type vortex generator enhancing heat exchange of solar air-drier and air-heater on the gas side,and investigated the mechanism of heat transfer enhancement and drag reduction by the influence of vortex generators on the coherent structure of turbulent boundary *** flow and heat transfer characteristics of rectangle channel with bevel-cut half-elliptical column vortex generators were obtained using large eddy simulation(LES)and the hydromechanics software *** instantaneous properties of velocity,temperature and pressure in channel were *** coherent structure of turbulent boundary layer flow was showed,and the characteristic of vortex induced by inclined-cut semi-ellipse vortex generator and its influence on turbulent coherent structure were *** the effect mechanism of turbulent coherent structure on flow field,pressure field and temperature field was *** on the results,the heat transfer coefficient and drag reduction of the new vortex generator with different pitch angles were ***,the coherent effects of the increased wall heat transfer and the decreased skin friction do not satisfy the Reynolds *** turbulent coherent structure can be controlled through the geometry of the vortex generator,so the heat transfer and drag reduction can also be *** we can seek suitable form of vortex generator and structure parameters,in order to achieve the enhanced heat transfer and flow of drag reduction in the solar air-heater and solar air-drier.

关键词： large eddy simulation vortex generator bevel-cut half-elliptical column coherent structure heat transfer enhancement

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Partitioning series-parallel multigraphs into υ*-excluding edge covers

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Science china Mathematics 2006年第8期49卷 1082-1093页

作者： LIU Guizhen, DENG Xiaotie & XU Changqing School of Mathematics and System Science, Shandong university, Jinan 250100, china department of Computer Science, City university of Hong Kong, Kowloon, Hong Kong, china department of Applied Mathematics, hebei university of technology, tianjin 300130, china School of Mathematics and System Science Shandong University Jinan 250100 China department of Computer Science City University of Hong Kong Kowloon Hong Kong Hong Kong department of Applied Mathematics Hebei University of Technology Tianjin 300130 China

We prove that, for any given vertexν* in a series-parallel graph G, its edge set can be partitioned into k= min{k′(G) + 1,δ(G)} subsets such that each subset covers all the vertices of G possibly except forν*, whereδ(G) is the minimum degree of G and k′(G) is the edge-connectivity of G. In addition, we show that the results in this paper are best possible and a polynomial time algorithm can be obtained for actually finding such a partition by our proof.

关键词： series-parallel graph, edge-connectivity, edge cover coloring, min-max theorem.

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Principle of limitation of physical quantities and cyclic universe

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Science china(physics,Mechanics & Astronomy) 2008年第5期51卷 451-458页

作者： HE GuoZhu department of physics,Nankai university,tianjin 300071,china department of physics Nankai University Tianjin China

A close study of Heisenberg uncertainty principles reveals many significant facts,and all four major physical quantities,energy,time,momentum and length,have both lower and upper ***,many questions come *** are these limits?Some answers may lead to the understanding of the development of our *** is the shortest limit of time?At the beginning of big bang,there exists a tre-mendously short time,the Planck *** may be just the shortest time limit in our *** longest time limit might be the lifetime of our *** longest length might be the final diameter of our expanding *** these lead to a finite *** more coupling formulae are formed for the other two pairs of physical quantities,mass and speed,thermal energy and *** four physical quantities must also have *** already knew that speed has upper limit and temperature has lower *** these two formulae,Planck and Einstein equations are derived *** most other physical quantities are somewhat related to these major physical quantities,it seems that there exists a principle of limitation of physical quantities.A quantitative sketch of big bang is *** also shows that our universe will contract back to another big *** principle of limitation opens up some fields of *** may bring nature back to the harmony and determined world described by classical physics.

关键词： principle of limitation of physical quantities limits coupling formulae cyclic universe extension of conven-tional quantum mechanics no uncertainty for physical quantities quantitative evaluation of big bang

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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

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