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Complete multiple round quantum dense coding with quantum logical network

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Chinese science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2,LI XiHan1,2,DENG FuGuo1,2,3,ZHOU Ping1,2 & ZHOU HongYu1,2,3 1 Key Laboratory of Beam technology and Material Modification of Ministry of Education,beijing normal university,beijing 100875,china 2 Institute of Low Energy Nuclear Physics,and Department of Material science and Engineering,beijing normal university,beijing 100875,china 3 beijing Radiation Center,beijing 100875,china Key Laboratory of Beam technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠

Constraints of f(R) gravity in Palatini approach with observational Hubble data

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science china(Physics,Mechanics & Astronomy) 2011年第8期54卷 1378-1383页

作者： ZHAI ZhongXu & LIU WenBiao Department of Physics, Institute of Theoretical Physics, beijing normal university, beijing 100875, china 1. Department of Physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2/2 to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.41) by OHD only and (Ωm0, n) = (0.23, 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.

关键词： f(R) gravity OHD CMB BAO accelerating expansion dark energy

Estimation of Spectral Gap for Markov Chains

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Acta Mathematica Sinica,English Series 1996年第4期12卷 337-360页

作者： Chen Mufa Department of Mathematics beijing normal university beijing, 100875 china Department of Mathematics Beijing Normal University Beijing China

The study of the convergent rate (spectra gap) in the L^2-sense is motivated from several different fields: probability statistics, mathematical physics, computer science and so on and it is now an artive research topic. Based on a new approach (the coupling technique) introduced in [7] for the estimate of the convergent rate and as a continuation of [4],[5],[7-9],[23] and [24], this paper studies the estimate of the rate for time-continuous Markov chains. Two variational formulas for the rate are presented here for the first time for birth-death processes. For diffusions, similar results are presented in an accompany paper [10]. The new formulas enable us to recover or improve the main known results. The connection between the sharp estimate and the corresponding eigenfunction is explored and illustrated by various examples. A previous result on optimal Markovian couplings is also extended in the paper.

关键词： Markov chains Spectral gap Couplings

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2, LIU Chang-hua2, ZHANG He-bing2 1. college of resources science and technology, beijing normal university, beijing 100875, china 2. School of Surveying and Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000, china [a] college of resources science and technology Beijing Normal University Beijing 100875 China [b] School of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

Synthesis of superheavy nuclei with ^(238)U target

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3 & BAO JingDong2,4 1 Key Laboratory of Beam technology and Material Modification of Ministry of Education,beijing normal university,beijing 100875,china 2 Department of Physics,beijing normal university,beijing 100875,china 3 china Institute of Atomic Energy,beijing 102413,china 4 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 238U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112 and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 238U target

Effect of surfactants on the structure and photoelectric properties of ITO films by sol-gel method

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Rare Metals 2010年第2期29卷 143-148页

作者： LIU Jiaxiang, WU Da, ZHANG Nan, and WANG Yue college of Materials science and Engineering, beijing university of Chemical technology, beijing 100029, china college of Materials science and Engineering Beijing University of Chemical Technology

The Indium tin oxide（ITO） thin film possesses excellent photoelectric properties that enable it to act as an ideal transparent *** obtain high-quality ITO films through sol-gel method, the ionic surfactant monoethanolamine and the non-ionic surfactant polyethylene glycol（PEG） were added to the ITO precursor *** influences of surfactants on the structural and photoelectric properties of ITO film samples were *** patterns indicated that surfactant monoethanolamine contributed to film predominant grain orientation along the（400） *** high transmittance（over 95%） was attributed to the preferred orientation and the grain size expansion of ITO *** showed that the surface particle size and the morphology of ITO films were strongly dependent on the kind of surfactants *** to the shortwave region, the absorption edge of the films exhibited the Burstein-Moss shift.

关键词： surfactants indium tin oxide films sol-gel structure photoelectricity

The information entropy of a static dilaton black hole

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science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 113-125页

作者： LIU ChengZhou Institute of Theoretical Physics, Binzhou university, Binzhou 256600, china Department of Physics, beijing normal university, beijing 100875, china 1. Institute of Theoretical Physics Binzhou University Binzhou 256600 China 2. Department of Physics Beijing Normal University Beijing 100875 China

In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed.

关键词： black hole entropy holographic principle non-commutative quantum field theory event horizon loop quantum gravity

Problems in wavelet analysis of hydrologic series and some suggestions on improvement

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Progress in Natural science:Materials International 2007年第1期17卷 80-86页

作者： WANG Hongrui, YE Letian, LIU Changming, YANG Chi and LIU Peng ( college of Water sciences, beijing normal university, beijing 100875, china Key Laboratory for Water and Sediment sciences, Ministry of Education, beijing 100875, china School of Mathematical sciences, Peking university, beijing 100089, china college of Engineering sciences, university of Region, Canada) [a]college of Water sciences Beijing Normal University Beijing China [b]Key Laboratory for Water and Sediment sciences Ministry of Education Beijing China [c]School of Mathematical sciences Peking University Beijing China [d]college of Engineering sciences University of Region Canada

Applying the wavelet theory and methods to investigate the hydrologic processes such as precipitation and runoff is a hot field. However, several aspects in research are usually ignored: the effect of admissible condition of wavelet functions and the disturbance of noises for the detection of periods, the effect of the length of a hydrologic time-series on the final result, and the choice between the anomaly and the original time series for wavelet analysis. In this paper, these issues are fully discussed. Precipitation data from Lanzhou Precipitation Station are taken for case study. The result indicates that in the wavelet analysis of hydrologic series, denoise methods should be used to eliminate the influence of noises. The MexHat wavelet function satisfies the admissible condition, which ensures that the periodic properties of hydrologic processes can be well represented by using the MexHat wavelet for decomposition. The affected range of hydro-logic series which should be discarded before analysis is given. It is also suggested that the anomaly series should be used to highlight the actual undulation of the hydrologic series.

关键词： wavelet analysis hydrologic process admissible condition noise period.

Progress in the study of molecular organized assemblies by dielectric relaxation spectroscopy

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Progress in Natural science:Materials International 2006年第3期16卷 221-230页

作者： ZHAO Kongshuang, HE Kejuan and WEI Suxiang (Department of Chemistry, beijing normal university, beijing 100875, china Department of Chemistry, South china normal university, Guangzhou 510631, china) [a]Department of Chemistry Beijing Normal University Beijing China [b]Department of Chemistry South China Normal University Guangzhou China

Because dielectric spectroscopy covers a great many problems in physical and chemical systems occurring in an extremely wide frequency range, the study of this method plays an important role in physical chemistry. As an effective tool to detect inner properties of substance systems, the dielectric spectroscopy method is widely used in chemical systems and has been dramatically developed in recent decade. This review paper describes the applications of the dielectric spectroscopy in the chemical field, and main concentrations are focused on the micelle, microemulsion and other so-called molecular organized assemblies. Some dielectric principles and models proposed for these systems are introduced. In addition, recent technical developments in dielectric spectroscopy and developing trend of this method in other chemical systems are reviewed.

关键词： dielectric relaxation micelle microemulsion vesicle relaxation time.