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991.
Photon quantum statistics of light can be shown by the high-order coherence. The fourth-order coherences of various quantum states including Fock states, coherent states, thermal states and squeezed vacuum states are investigated based on a double Hanbury Brown–Twiss (HBT) scheme. The analytical results are obtained by taking the overall efficiency and background into account. 相似文献
992.
<正>Photon quantum statistics of light can be shown by the high-order coherence.The fourth-order coherences of various quantum states including Fock states,coherent states,thermal states and squeezed vacuum states are investigated based on a double Hanbury Brown-Twiss(HBT) scheme.The analytical results are obtained by taking the overall efficiency and background into account. 相似文献
993.
Based on a systematic investigation of J/ψ(ψ) → VP,where V and P stand for light vector and pseudoscalar mesons,we identify the role played by the electromagnetic(EM) transitions and intermediate meson loop transitions,which are essential ingredients for understanding the J/ψ and ψ couplings to VP.We show that on the one hand,the EM transitions have relatively larger interferences in ψ→ρπ and K*K+c.c.as explicitly shown by vector meson dominance(VMD).On the other hand,the strong decay of ψ receives relatively larger destructive interferences from the intermediate meson loop transitions.By identifying these mechanisms in an overall study of J/ψ(ψ)→VP,we provide a coherent understanding of the so-called "ρπ puzzle". 相似文献
994.
As feature size keeps scaling down,process variations can dramatically reduce the accuracy in the estimation of interconnect performance.This paper proposes a statistical Elmore delay model for RC interconnect tree in the presence of process variations.The suggested method translates the process variations into parasitic parameter extraction and statistical Elmore delay evaluation.Analytical expressions of mean and standard deviation of interconnect delay can be obtained in a given fluctuation range of interconnect geometric parameters.Experimental results demonstrate that the approach matches well with Monte Carlo simulations.The errors of proposed mean and standard deviation are less than 1% and 7%,respectively.Simulations prove that our model is efficient and accurate. 相似文献
995.
LI ZhiHong SU Jun GUO Bing LI ZhiChang BAI XiXiang LIU JianCheng LI YunJu YAN ShengQuan WANG BaoXiang WANG YouBao LIAN Gang ZENG Sheng LI ErTao CHEN YongShou SHU NengChuan FAN QiWen & LIU WeiPing China Institute of Atomic Energy Beijing China 《中国科学:物理学 力学 天文学(英文版)》2010,(4)
The angular distribution of the 12C(7Li,6He)13N reaction at E(7Li) = 44.0 MeV was measured at the HI-13 tandem accelerator of Beijing, China. The asymptotic normalization coefficient (ANC) of 13N → 12C + p was derived to be (1.64 ± 0.11) fm-1/2 through the distorted wave Born approximation (DWBA) analysis. The ANC was then used to deduce the astrophysical S (E) factors and reaction rates for the 12C(p,γ)13N direct capture reaction at energies of astrophysical relevance. 相似文献
996.
CHEN RuiLin ZENG QingYuan HUANG YunQing XIANG Jun WEN Ying GUO XiaoGang YIN ChangJun DONG Hui & ZHAO Gang Hunan Key Laboratory for Computation Simulation in Science Engineering Xiangtan University Xiangtan China School of Civil Engineering & Mechanics School of Civil Architecture Central South University Changsha AMEC Toronto MAG Canada 《中国科学:物理学 力学 天文学(英文版)》2010,(4)
Based on the analysis theory of random energy of train derailment, an analysis theory of random energy of train derailment in wind is suggested. Two methods are proposed -the time domain method and the frequency domain method of analysis theory of random energy of train derailment in wind. The curves of σ pw -v under various wind speeds are obtained through the computation. The original curve of σ p -v is expanded, which turns the analysis theory of random energy of train derailment into the all-weather theory. Train derailment condition has been established under wind action. The first and second criterions of train derailment have been proposed in light of wind action. The analysis of train derailment cases at home or abroad is made, in- cluding the first analysis of Xinjiang train derailment case encountered 13-level of gale, which explained the inevitability of train derailment. The analysis theory of random energy of train derailment in wind shows its validity and accuracy. The input energy σ pw of the transverse vibration of train-track(bridge)-wind system is linked to train speed. With the establishment of the analysis theory of random energy of train derailment in wind, It is likely to initiate an all-weather speed limit map for a train or any high-speed train. 相似文献
997.
Lin‐Jian Zhu Jian Wang Tie‐Gang Reng Chun‐Yan Li Dong‐Cai Guo Can‐Cheng Guo 《Journal of Physical Organic Chemistry》2010,23(3):190-194
Six tetraphenylporphyrins (TRPPH2) with different horizontal substituents R (R = H, CH3, OH, F, Cl, Br) were synthesized, and the organic light‐emitting diode (OLED) devices with a general configuration of ITO/TPD/Alq3:2%TRPPH2/Alq3/Al were prepared. The substituted TRPPH2 was used as the host dopant, 4,4‐bis‐(m‐tolyphenylamino)biphenyl (TPD) was used as a hole‐transporting material, and aluminum tris(8‐quinolinolato) (Alq3) was used as an electron‐transporting material. The electroluminescent (EL) properties of these devices were studied to understand the light emitting properties of the substituted TRPPH2. Previous studies have found that the color emitted by the devices was dependent on the TRPPH2 dye concentration. The electronic effect of the horizontal substituents R of TRPPH2 influenced the turn‐on voltage, brightness, and power efficiency of the devices. Also, the electroluminescence performance of the porphyrin‐doped OLED devices depended on the effectual overlaps between the emission of electron‐transporting material and the absorption of the dopants. This means that it is possible to evaluate the electroluminescence performance of the porphyrin‐doped OLED devices based on the emission of electron‐transporting material and the absorption of the dopants. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
998.
Gang Yu 《Transactions of the American Mathematical Society》2006,358(4):1563-1584
In this paper, we study a class of elliptic curves over with -torsion group , and prove that the average order of the -Selmer groups is bounded.
999.
Zhang Guangji Zhang Cheng Liu Zixin Gang Jiatai 《Fuzzy Optimization and Decision Making》2006,5(2):177-186
Following the seminal work of Xi on the definition of fuzzy ideal in BCI-algebras, three new kinds of definitions of fuzzy
ideal of BCI-algebras are proposed. First, by the use of the relations between fuzzy points and fuzzy sets, the definition
of a (s,t]-fuzzy ideals of BCI-algebras is introduced. The acceptable nontrivial concepts obtained in this manner are the
- fuzzy ideals and
-fuzzy ideals. Second, based on the concept of falling shadow, a theoretical approach of fuzzy ideal is established and the
fuzzy ideal based on t-norm is proposed. Finally, by the use of the implication operators of fuzzy logic, an R-fuzzy ideals
is proposed and relations between the (s,t]-fuzzy ideals and R-fuzzy ideals are discussed.
*Foundation Item:Supported by NNSF of China(60274016). Biography:Zhang Guang-ji(1947-),male,Professor 相似文献
1000.