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Deviation Property of Periodic Measures in C^1 Non-uniformly Hyperbolic Systems with Limit Domination

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Acta Mathematica Sinica,English Series 2012年第9期28卷 1727-1740页

作者： sheng qian Wen Xiang SUN Xue Ting TIAN Department of Mathematics Peking University Academy of Mathematics and Systems Science Chinese Academy of Sciences

In a C1 non-uniformly hyperbolic systems with limit domination, we consider the periodic measures that supported on the Pesin set and keep a distance at least 6 to a hyperbolic ergodic measure μ given before. And then, we bound from top the exponential growth rate of such periodic measures by the supremum of measure theoretic entropy on a closed set.

关键词： Exponential growth rate generalized entropy large deviation limit domination Pesin set

ALTERNATING PROJECTION BASED PREDICTION-CORRECTION METHODS FOR STRUCTURED VARIATIONAL INEQUALITIES

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Journal of Computational Mathematics 2006年第6期24卷 693-710页

作者： Bing-sheng He Li-zhi Liao Mai-jian qian Department of Mathematics Nanjing University Nanjing 210093 China Department of Mathematics Hong Kong Baptist University Hong Kong China Department of Mathematics California State University FuUerton CA 92834 USA

The monotone variational inequalities VI（Ω, F） have vast applications, including optimal controls and convex programming. In this paper we focus on the VI problems that have a particular splitting structure and in which the mapping F does not have an explicit form, therefore only its function values can be employed in the numerical methods for solving such problems. We study a set of numerical methods that are easily implementable. Each iteration of the proposed methods consists of two procedures. The first （prediction） procedure utilizes alternating projections to produce a predictor. The second （correction） procedure generates the new iterate via some minor computations. Convergence of the proposed methods is proved under mild conditions. Preliminary numerical experiments for some traffic equilibrium problems illustrate the effectiveness of the proposed methods.

关键词： Structured variational inequality Monotonicity Prediction-correction method.

Estimating and Mapping Extreme Ice Accretion Hazard and Load Due to Freezing Rain at Canadian Sites

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International Journal of Disaster Risk Science 2023年第1期14卷 127-142页

作者： Chao sheng qian Tang H.P.Hong Department of Civil and Environmental Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

The ice accretion load in Canadian structural design codes is developed based on an operational ice accretion prediction *** the present study,three models are employed to predict the ice accretion amount on a flat surface and horizontal wire at Canadian *** results confirm that the model used by Canadian practice for predicting ice accretion leads to a conservative estimate as compared to the remaining two *** results also indicate that the use of the Gumbel distribution for the annual maximum ice accretion is adequate for regions prone to ice accretion and that the lognormal distribution may be considered for regions with a moderate or negligible amount of ice *** of the ice accretion hazard at five selected Canadian sites are *** analysis of an equivalent wind speed that is concurrent with the iced wire is carried out,showing that the concurrent wind speed for the 50-year return period value of the annual maximum ice accretion amount is smaller than the 50-year return period value of the annual maximum wind *** is shown that the statistical characteristics of the annual maximum concurrent wind speed on iced wire differ from that of the annual maximum wind speed.

关键词： Canada Concurrent wind speed Hazard mapping Ice accretion Probabilistic analysis

Further Notes on the Gaussian Beam Expansion

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Chinese Physics Letters 2012年第2期29卷 116-118页

作者： dai Yu-Rong DING De-sheng Department of Physics Southeast UniversityNanjing 210096 School of Electronic Science and Engineering Southeast UniversityNanjing 210096 Laboratory of Modern Acoustics of MOE Nanjing UniversityNanjing 210093

We provide alternatively a simple way of computing the Fresnel field integral,a further extension to the Gaussianbeam *** a known result that the circ function is approximately decomposed into a sum of Gaussian functions,the zero-order Bessel function of the first kind is similarly expanded by the Bessel-Fourior *** expansions are together inserted in this integral,which is then expressible in terms of the simple algebraic *** approach is useful in treatment of the field radiation problem for a large and important group of piston sources in *** examples,the calculation results for the uniform and the simply supported piston sources are presented,in a good agreement with those evaluated by numerical integration.

关键词： functions Gaussian Bessel

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer Constructed by 3,5-Dimethylbenzoic Acid with 4,4'-Bipyridine

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1213-1216页

作者： ZHANG Chun-Hua CHEN Man-sheng KUANG dai-Zhi Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China

A novel manganese coordination polymer [Mn（L）2（bipy）]n （HL = 3,5-dimethylbenzoic acid, 4,4＇-bipy = 4,4＇-bipyridine） has been synthesized by a hydrothermal method. The molecular and crystal structures were determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 2.0996（8）, b = 1,1835（5）, c = 0.9958（4） nm, β = 110.161（5）°, V = 2,3229（16） nm^3, Z = 4, C28H26MnN2O4, Mr = 509.45, Dc= 1.457 g/cm^3,μ = 0.607 mm^-1, F（000） = 1060, Rim = 0.0566, R = 0.0334 and wR = 0.1078. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 4,4＇-bipy and four oxygen atoms from 3,5-dimethylbenzolate molecules, completing an octahedral geometry. The 4,4＇-bipy molecules bridge the infinite chain [Mn（L）2（bipy）]n to form a two-dimensional layer.

关键词： manganese coordination polymer hydrothermal synthesis crystal structure

Nucleosomal Context of Binding Sites Influences Transcription Factor Binding Affinity and Gene Regulation

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Genomics, Proteomics & Bioinformatics 2009年第4期7卷 155-162页

作者： Zhiming dai Xianhua dai qian Xiang Jihua Feng Electronic Department Sun Yat-Sen University Guangzhou 510006 China.

Transcription factor （TF） binding to its DNA target site plays an essential role in gene regulation. The location, orientation and spacing of transcription factor binding sites （TFBSs） also affect regulatory function of the TF. However, how nucleosomal context of TFBSs influences TF binding and subsequent gene regulation remains to be elucidated. Using genome-wide nucleosome positioning and TF binding data in budding yeast, we found that binding affinities of TFs to DNA tend to decrease with increasing nucleosome occupancy of the associated binding sites. We further demonstrated that nucleosomal context of binding sites is correlated with gene regulation of the corresponding TF. Nucleosome-depleted TFBSs are linked to high gene activity and low expression noise, whereas nucleosome-covered TFBSs are associated with low gene activity and high expression noise. Moreover, nucleosome-covered TFBSs tend to disrupt coexpression of the corresponding TF target genes. We conclude that nucleosomal context of binding sites influences TF binding affinity, subsequently affecting the regulation of TFs on their target genes. This emphasizes the need to include nucleosomal context of TFBSs in modeling gene regulation.

关键词： gene regulation nucleosome transcription factor binding site

Advanced Transmission Electron Microscopy for Identification of Atomic-Scale Configurations of Zeolite-Supported Metal Catalysts

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Chinese Journal of Chemistry 2022年第19期40卷 2371-2373页

作者： Xuan Tang Jiajie Ye Yun Guo sheng dai Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science and TechnologyShanghai200237 China Key Laboratory for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237 China

Zeolite-supported metal catalysts have important applications in various catalytic reactions,but unveiling their atomic-scale structures is always a grand *** developed transmission electron microscopy(TEM)characterization techniques,e.g.,integrated differential-phase contrast(iDPC)scanning transmission electron microscopy(STEM)is emerging as a powerful tool for visualizing the electron beam-sensitive materials at atomic resolution,thus,providing new opportunities for imaging the exact configurations of metal species in the various channels of *** emerging topic summarizes recent progress utilizing iDPC-STEM-related technique for determination of the structures of metal species in zeolites that should offer insights into the structure-property relationships of zeolite-supported metal catalysts.A brief perspective about the new TEM technique is also presented,showing prospects in this field that will stimulate further scientific research in zeolite-supported metal catalysts.

关键词： Metal-zeolite Catalyst structure Heterogeneous catalysis TEM characterization Electron microscopy

Non-Gaussian feature of the output field from a double qubit-cavity ultrastrong coupling system

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Communications in Theoretical Physics 2024年第7期76卷 30-36页

作者： sheng-wen Xu Shi-yu dai Teng Zhao Center for Quantum Science and Technology Jiangxi Normal UniversityNanchang 330022China

We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode *** the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy *** further analyze the intensity-amplitude correlation of the output field in these two novel *** the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output *** findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are ***,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more *** suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.

关键词： ultrastrong coupling non-Gaussian intensity-amplitude correlation

Strong quartic anharmonicity,ultralow thermal conductivity,high band degeneracy and good thermoelectric performance in Na_(2)TlSb

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npj Computational Materials 2023年第1期9卷 2167-2175页

作者： Tongcai Yue Yinchang Zhao Jun Ni sheng Meng Zhenhong dai Department of Physics Yantai UniversityYantai 264005P.R.China Department of Physics Tsinghua UniversityBeijing 100084P.R.China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190P.R.China Collaborative Innovation Center of Quantum Matter Beijing 100084P.R.China

We employ first-principles calculations combined with self-consistent phonon theory and Boltzmann transport equations to investigate the thermal transport and thermoelectric properties of full-Heusler compound Na_(2)*** findings exhibit that the strong quartic anharmonicity and temperature dependence of the Tl atom with rattling behavior plays an important role in the lattice stability of Na_(2)*** find that soft Tl-Sb bonding and resonant bonding in the pseudocage composed of the Na and Sb atoms interaction is responsible for ultralowκ***,the multi-valley band structure increases the band degeneracy,results in a high power factor in p-type Na_(2)*** coexistence of ultralowκL and high power factor presents that Na_(2)TlSb is a potential candidate for thermoelectric ***,these findings help to understand the origin of ultralowκL of full-Heusler compounds with strong quartic anharmonicity,leading to the rational design of full-Heusler compounds with high thermoelectric performance.

关键词： harmonic bonding thermal