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Isospin dependence of nucleon effective masses in neutron-rich matter

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Nuclear Science and Techniques 2016年第6期27卷 25-32页

作者： bao-An li bao-Jun Cai lie-Wen Chen Xiao-Hua li Department of Physics and Astronomy Texas A&MUniversity-Commerce Department of Physics and Astronomy and Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong University School of Nuclear Science and Technology University of South China

In this talk,we first briefly review the isospin dependence of the total nucleon effective mass M Jinferred from analyzing nucleon-nucleus scattering data within an isospin-dependent non-relativistic optical potential model,and the isospin dependence of the nucleon E-mass M;E J obtained from applying the Migdal–Luttinger theorem to a phenomenological single-nucleon momentum distribution in nuclei constrained by recent electron-nucleus *** information about the isospin dependence of both the nucleon total effective mass and E-mass,we then infer the isospin dependence of nucleon k-mass using the well-known relation M_J~*=M_ J^(*1E).Implications of the results on the nucleon mean free path in neutron-rich matter are discussed.

关键词：同位旋相关有效质量单核子核物质丰中子平均自由程非相对论分析数据

Flow stress model considering the transformation-induced plasticity effect and the inelastic strain recovery behavior

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 185-191页

作者： Hai-yan Yu li bao School of Automotive Engineering Tongji University Shanghai 200092 China

On the basis of continuum mechanics and the Mori-Tanaka mean field theory, a micro-mechanical flow stress model that considered both the transformation-induced plasticity （TRIP） effect and the inelastic strain recovery behavior of TRIP multiphase steels was presented. The relation between the volume fraction of constituent phases and plastic strain was introduced to characterize the transformation-induced plasticity effect of TRIP steels. Loading-unloading-reloading uniaxial tension tests of TRIP600 steel were carried out and the strain recovery behavior after unloading was analyzed. From the experimental data, an empirical elastic modulus expression is extracted to characterize the inelastic strain recovery. A comparison of the predicted flow stress with the experimental data shows a good agreement. The mechanism of the transformation-induced plasticity effect and the inelastic recovery effect acting on the flow stress is also discussed in detail.

关键词： flow stress transformation-induced plasticity inelastic strain elastic modulus

Existence of 3-round zero-knowledge proof systems for NP

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Science in China(Series F) 2008年第3期51卷 273-282页

作者： li HongDat li bao State Key Lab of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049China

This paper considers the existence of 3-round zero-knowledge proof systems for NP. Whether there exist 3-round non-black-box zero-knowledge proof systems for NP language is an open problem. By introducing a new interactive proof model, we construct a 3-round zero-knowledge proof system for graph 3-coloring under standard assumptions. Our protocol is a non-black-box zero-knowledge proof because we adopt a special strategy to prove the zero-knowledge property. Consequently, our construction shows the existence of 3-round non-black-box zero-knowledge proof for all languages in NP under the DDH assumption.

关键词： interactive proof zero-knowledge proof non-black-box simulation DDH assumption

Syndrome series of one point algebraic-geometric codes and majority voting scheme

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Chinese Science Bulletin 1998年第7期43卷 540-544页

作者： bao li Guozhen Xiao Xidian Univ Inst Informat Secur Xian 710071 Peoples R China

A type of recurring relations on syndrome series is presnted. After some important theorems are established, an algorithm for computing a minimal polynomial set is presented. Finally an algorithm for determining the u... 详细信息

关键词： algebraic-geometric code decoding recurring relation majority voting.

Discontinuous Galerkin Finite Element Method for a Nonlinear Boundary Value Problem

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 521-532页

作者： Tie ZHANG Jian-bao li Department of Mathematics Northeastern University

In this paper, we investigate the a priori and a posteriori error estimates for the discontinuous Galerkin finite element approximation to a regularization version of the variational inequality of the second kind. We show the optimal error estimates in the DG-norm （stronger than the H1 norm） and the L2 norm, respectively. Furthermore, some residual-based a posteriori error estimators are established which provide global upper bounds and local lower bounds on the discretization error. These a posteriori analysis results can be applied to develop the adaptive DG methods.

关键词： variational inequality DG method optimal error estimate a posteriori error analysis

Astrophysical constraints on a parametric equation of state for neutron-rich nucleonic matter

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Nuclear Science and Techniques 2018年第12期29卷 62-70页

作者： Nai-Bo Zhang bao-An li Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Institute of Space Sciences Shandong University Department of Physics and Astronomy Texas A&M University-Commerce

Extracting the equation of state(EOS) and symmetry energy of dense neutron-rich matter from astrophysical observations is a long-standing goal of nuclear astrophysics. To facilitate the realization of this goal, the feasibility of using an explicitly isospin-dependent parametric EOS for neutron star matter was investigated recently in [1–3]. In this contribution, in addition to outlining the model framework and summarizing the most important findings from [1–3], we report a few new results regarding constraining parameters characterizing the highdensity behavior of nuclear symmetry energy. In particular,the constraints on the pressure of neutron star matter extracted from combining the X-ray observations of the neutron star radius, the minimum–maximum mass M=2:01 M_⊙, and causality condition agree very well with those extracted from analyzing the tidal deformability data by the liGO ? Virgo Collaborations. The limitations of using the radius and/or tidal deformability of neutron stars to constrain the high-density nuclear symmetry energy are discussed.

关键词：中子星物质天体物理学方程状态核子数据提取调查结果模型框架

A novel blind deconvolution algorithm using single frequency bin

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1271-1276页

作者： ZHANG Gui-bao li Jia-wen li Cong-xin National Die ＆ Mold CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China

Former frequency-domain blind devolution algorithms need to consider a large number of frequency bins and recover the sources in different orders and with different amplitudes in each frequency bin,so they suffer from permutation and amplitude indeterminacy troubles. Based on sliding discrete Fourier transform,the presented deconvolution algorithm can directly recover time-domain sources from frequency-domain convolutive model using single frequency bin. It only needs to execute blind sepa-ration of instantaneous mixture once there are no permutation and amplitude indeterminacy troubles. Compared with former algorithms,the algorithm greatly reduces the computation cost as only one frequency bin is considered. Its good and robust per-formance is demonstrated by simulations when the signal-to-noise-ratio is high.

关键词： Blind deconvolution Single frequency bin Convolutive mixture

Causes for the Unimodal Pattern of Leaf Carbon Isotope Composition in Abies faxoniana Trees Growing in a Natural Forest along an Altitudinal Gradient

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Journal of Mountain Science 2015年第1期12卷 39-48页

作者： ZHAO Hong-xia DUAN bao-li LEI Yan-bao Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences

Leaf morphological and physiological traits of Abies faxoniana growing in a natural forest along an altitudinal gradient were measured with the aim to identify the central mechanism for the marked variation in foliar δ13C determined by an isotope ratio mass spectrometer. There is a unimodal pattern of plant functional traits in these temperate and semi- humid areas. Stomatal parameters, specific leaf area, and C/N ratio increased, whereas C, N and δ13C values decreased with increasing altitude below 3000 m a.s.1. In contrast, they exhibited opposite trends above 3000 m a.s.l.. Our results demonstrated that high-altitude plants achieve higher water use efficiency （WUE） at the expense of decreasing nitrogen use efficiency （NUE）, whereas plants at 3000 m can maintain a relatively higher NUE but a lower WUE. Such intra-specific differences in the trade-off between NUE and WUE may partially explain the altitudinal distribution of the plants in relation to moisture and nutrient availability. Our results clearly indicate that the functional relations between nutritional status and the structure of leaves are responsible for the altitudinal variations associated with δ13C. The pivotal role of specific leaf area in regulating plant adaptive responses provides a potential physiological mechanism for the observed growth advantage of populations occupying the medium altitude. These adaptive responses altitudinal gradients showed that an altitude to of approximately 3000 m a.s.1, is the optimum distribution zone for A. faxoniana, allowing the most vigorous growth and metabolism. These results improve our understanding of the various roles of environmental and biotic variables upon δ13C dynamics and provide useful information for subalpine coniferous forest management.

关键词： Abiesfaxoniana Age Altitude Carbonisotope ratio Nitrogen content

HEAT-RESISTANT COMPOSITES CURED BY ELECTRON BEAM

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Chinese Journal of Polymer Science 2001年第1期19卷 53-57页

作者： Jian-wen bao Yang li Xiang-bao Chen Feng-mei li National Key Lab of Advanced Composites Institute of Aeronautical Materials Beijing 100095 China National Key Lab of Advanced Composites Institute of Aeronautical Materials Beijing 100095 China National Key Lab of Advanced Composites Institute of Aeronautical Materials Beijing 100095 China Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100877 China

Electron beam (EB) curing of composites has many advantages. Heat-resistant EB-curing composites could substitute polyimide composites used in aeronautical engines. In this paper, the effects of catalyst and dose on the cured resin were investigated. The heat-resistance of the resin cured by EB was evaluated by dynamic mechanical analysis (DMA). The experimental results show that the mechanical properties of the composites cured by EB could meet the specifications of aeronautical engines at 250 degreesC.

关键词： electron beam curing composites epoxy heat-resistance