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The spectral properties of Fermi blazars:the spectral sequence and unification of blazars

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Research in Astronomy and Astrophysics 2013年第1期13卷 5-14页

作者： Luo-En Chen huai-zhen li Ting-Feng Yi Shu-Bai Zhou Kai-Yi li Physics Department Yuxi Normal University Physics Department Yunan Normal University Physics Department Yunan University

Using a large sample of blazars of the Fermi observations presented by Abdo et al., we constructed a sample of blazars including high energy peaked BL Lac objects （HBLs）, low energy peaked BL Lac objects （LBLs） and flat-spectral ra- dio quasars （FSRQs）. These unique characteristics make it possible to unambiguously address the question of how HBLs, LBLs and FSRQs are related. In this paper, we investigated the relationship between X-ray and 7-ray spectral indices （~^-aT）, as well as the relationship between the broadband spectral indices （~ro--ar~, ~ro--~ox, OZro--O^x7 and ~r^-~xT） for this sample. The color-color diagram shows that there is a significant correlation between both quantities when all three subclasses of blazars are considered, which suggests that there is a unified scheme for blazars. On the other hand, the a^-~7 diagram reveals that three kinds of blazars have different spectral energy distributions： the trend of HBLs is different from that of FSRQs and LBLs, whereas FSRQs and LBLs have a similar trend, which hints that FSRQs and LBLs have similar spectral properties, but HBLs have distinct spectral properties. In addi- tion, the broadband energy distributions also reveal the similar spectral properties with that of the Cx-C7 diagram. The spectral properties revealed from the Fermi sample do not support the blazar sequence reported by Fossati et al. and Ghisellini et al.

关键词： galaxies: active--BL Lacertae objects: general--galaxies: fundamentalparameters -- quasars: general

A Periodicity Analysis of the light Curve of 3C 454.3

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 421-429页

作者： huai-zhen li Guang-Zhong Xie Shu-Bai Zhou Hong-Tao liu Guang-Wei Cha li Ma li-Sheng Mao National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049 Yunnan Astronomical Center Yunnan University Kunming 650091 Physics Department Yunnan University Kunming 650091 Physics Department Yunnan Normal College Kunming 650091

We analyzed the radio light curves of 3C 454.3 at frequencies 22 and 37 GHz taken from the database of Metsaeovi Radio Observatory, and found evidence of quasi-periodic activity. The light curves show great activity with very complicated non-sinusoidal variations. Two possible periods, a very weak one of 1.57 ± 0.12 yr and a very strong one of 6.15 ±0.50 yr were consistently identified by two methods, the Jurkevich method and power specmun estimation. The period of 6.15 ± 0.50 yr is consistent with results previously reported by Ciaramella et al. and Webb et al. Applying the binary black hole model to the central structure we found black hole masses of 1.53 × 10^9M⊙ and 1.86 × 10^8M⊙, and predicted that the next radio outburst is to take place in 2006 March and April.

关键词： galaxies: individual (3C 454.3)-- galaxies: fundamental parameters-- methods:data analysis

Estimates of AGN Black Hole Mass and Minimum Variability Timescale

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 463-470页

作者： Guang-Zhong Xie Luo-En Chen huai-zhen li li-Sheng Mao Hong Dai Zhao-Hua Xie li Ma Shu-Bai Zhou National Astronomical Observatories Yunnan Observatory Chinese Academy of ScienceKunming 650011 Yunnan Astrophysics Center Yunnan University Kunming 650091 Physics Department Yunnan Normal University Kunming 650091 Physics Department Yuxi Normal College Yuxi 653100 Graduate University of Chinese Academy of Sciences Beijing 100049

Black hole mass is one of the fundamental physical parameters of active galactic nuclei （AGNs）, for which many methods of estimation have been proposed. One set of methods assumes that the broad-line region （BLR） is gravitationally bound by the central black hole potential, so the black hole mass can be estimated from the orbital radius and the Doppler velocity. Another set of methods assumes the observed variability timescale is determined by the orbital timescale near the innermost stable orbit around the Schwarzschild black hole or the Kerr black hole, or by the characteristic timescale of the accretion disk. We collect a sample of 21 AGNs, for which the minimum variability timescales have been obtained and their black hole masses （Mσ） have been well estimated from the stellar velocity dispersion or the BLR size-luminosity relation. Using the minimum variability timescales we estimated the black hole masses for 21 objects by the three different methods, the results are denoted by Ms, Mk and Md,respectively. We compared each of them with Mσ individually and found that：（1） using the minimum variability timescale with the Kerr black hole theory leads to small differences between Mσ and Mk, none exceeding one order of magnitude, and the mean difference between them is about 0.53 dex; （2） using the minimum variability timescale with the Schwarzschild black hole theory leads to somewhat larger difference between Mσ and Ms： larger than one order of magnitude for 6 of the 21 sources, and the mean difference is 0.74 dex; （3） using the minimum variability timescale with the accretion disk theory leads to much larger differences between Mσ and Md, for 13 of the 21 sources the differences are larger than two orders of magnitude; and the mean difference is as high as about 2.01 dex.

关键词： galaxies: active - galaxies: nuclei - galaxies: fundamental parameters

Possible properties of Te V spectra in PKS 2155–304

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Research in Astronomy and Astrophysics 2021年第3期21卷 227-234页

作者： Quan-Gui Gao Fang-Wu Lu Long-Hua Qin huai-zhen li Ju Ma Ji-Yang Ren Hai-Ru Zhao Ting-Feng Yi Physics Department Yuxi Normal UniversityYuxi 653100China Key Laboratory of Astroparticle Physics of Yunnan Province Kunming 650091China Department of Physics Yunnan Normal UniversityKunming 650092China

We present a one-zone homogeneous lepton-hadronic model and obtain steady-state spectra by solving the time-dependent equations to study a plausible origin of hard TeV spectra in PKS *** this model,we assume a steady electron and proton injection rate in the source and solve the non-linear time-dependent kinematic equations that self-consistently consist of proton-photon interaction,synchrotron radiation of electron/positron pairs and proton,inverse Compton scattering,and synchrotron *** employ this model to reproduce the multi-wavelength spectrum of PKS 2155-304,then find that the possible bump located at E~1 TeV which may originate from the synchrotron radiation of secondary electrons produced by Bethe-Heitler pair production,resulting in the hard TeV spectrum.

关键词： radiation mechanisms:non-thermal BL Lacertae objects:individual(PKS 2155–304) gamma rays:galaxies

Holographic superfluid ring with a weak link

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Science China(Physics,Mechanics & Astronomy) 2024年第11期Mechanics & Astronomy) .卷 33-42页

作者： Zhi-Hong li huai-Fan li Department of Physics Shanxi Datong University Institute of Theoretical Physics Shanxi Datong University

We explore the generation of topological defects in the course of a dynamical phase transition in a ring with a weak link, i.e., a SSS Josephson junction, from the AdS/CFT correspondence. By setting different parameters of the junction(width, steepness,depth) and the final temperature of the quench, the configurations of the charge density and condensate of the order parameters of the dual field theory are presented. Meanwhile, we observe that in the final equilibrium state, variations in parameters of the junctions only affect the configurations of the charge density and condensate of the order parameters, without altering their values outside the junction. However, variations in the final temperature will directly affect the values of the charge density and condensate of the order parameters outside of the junction. Moreover, in the final equilibrium state, we propose an analytic relation between the gauge-invariant velocity in the two superconducting states in the SSS Josephson junction, which agrees well with the numerical results.

关键词： AdS/CFT correspondence holographic superfluid holographic Josephson junction

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A three-dimensional co-continuous network structure polymer electrolyte with efficient ion transport channels enabling ultralong-life all solid-state lithium metal batteries

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Journal of Energy Chemistry 2024年第7期94卷 635-645页

作者： Meng Wang Hu Zhang Yewen li Ruiping liu huai Yang School of Chemical&Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering&School of Materials Science and Engineering Peking UniversityBeijing 100871China

Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility with ***,a novel all-solid polymer electrolyte(PPLCE)was fabricated by the copolymer network of liquid crystalline monomers and poly(ethylene glycol)dimethacrylate(PEGDMA)acts as a structural frame,combined with poly(ethylene glycol)diglycidyl ether short chain interspersed serving as mobile ion transport *** preparaed PPLCEs exhibit excellent mechanical property and out-standing electrochemical performances,which is attributed to their unique three-dimensional cocontinuous structure,characterized by a cross-linked semi-interpenetrating network and an ionic liquid phase,resulting in a distinctive nanostructure with short-range order and long-range ***,the addition of PEGDMA is proved to be critical to the comprehensive performance of the PPLCEs,which effectively modulates the microscopic morphology of polymer networks and improves the mechanical properties as well as cycling stability of the solid *** used in a lithiumion symmetrical battery configuration,the 6 wt%-PPLCE exhibites super stability,sustaining operation for over 2000 h at 30 C,with minimal and consistent overpotential of 50 *** resulting li|PPLCE|LFP solid-state battery demonstrates high discharge specific capacities of 160.9 and 120.1 mA h g^(-1)at current densities of 0.2 and 1 C,*** after more than 300 cycles at a current density of 0.2 C,it retaines an impressive 73.5%***,it displayes stable cycling for over 180 cycles at a high current density of *** super cycle stability may promote the application for ultralong-life all solid-state lithium metal batteries.

关键词： Solid-state electrolyte lithium-metal batteries liquid crystalline polymer Copolymer 3D co-continuous structure Long cycle stability

Mathematical Model,Numerical Simulation and Convergence Analysis of a Semiconductor Device Problem with Heat and Magnetic Influences

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 302-319页

作者： Chang-feng li Yi-rang YUAN huai-ling SONG School of Economics Shandong UniversityJinan 250100China Institute of Mathematics Shandong UniversityJinan 250100China College of Mathematics and Econometrics Hunan UniversityChangsha 410082China

In this paper,the authors discuss a three-dimensional problem of the semiconductor device type involved its mathematical description,numerical simulation and theoretical *** important factors,heat and magnetic influences are *** mathematical model is formulated by four nonlinear partial differential equations(PDEs),determining four major physical *** influences of magnetic fields are supposed to be weak,and the strength is parallel to the *** elliptic equation is treated by a block-centered method,and the law of conservation is *** computational accuracy is improved one *** equations are convection-dominated,thus are approximated by upwind block-centered *** difference can eliminate numerical dispersion and nonphysical *** diffusion is approximated by the block-centered difference,while the convection term is treated by upwind ***,the unknowns and adjoint functions are computed at the same *** characters play important roles in numerical computations of conductor device *** the theories of priori analysis such as energy estimates,the principle of duality and mathematical inductions,an optimal estimates result is *** a composite numerical method is shown for solving this problem.

关键词： three-dimensional conductor device problem with heat and magnetic influences upwind blockcentered differences elemental conservation of mass numerical analysis

Quasi-periodic Oscillation Analysis for the BL Lacertae Object 1823+568

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Research in Astronomy and Astrophysics 2022年第5期22卷 158-164页

作者： huai-zhen li Quan-Gui Gao Long-Hua Qin Ting-Feng Yi Qi-Rui Chen Physics Department Yuxi Normal UniversityYuxi 653100China Department of Physics Yunnan Normal UniversityKunming 650092China

We studied the optical band periodic variability of 1823+568 using the Jurkevich method,the Lomb-Scargle periodogram and the REDFIT38 software,and found evidence of quasi-periodic *** unprecedented variability with period P=283^(+17)_(-13) days was identified by three different analysis *** quasi-periodic variability most likely results from nonballistic helical jet motion driven by the orbital motion in a binary black hole *** the light-travel time effect,the real physical period is P_(d)=67.1 ***,we estimated that the primary black hole mass is M■1.92×10^(9) M_(⊙)to 3.43×10^(9) M_(⊙).

关键词： blazars(1823+568)-relativisticjets-non-thermalsources

Optimal dispatching strategy for residential demand response considering load participation

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Global Energy Interconnection 2024年第1期7卷 38-47页

作者： Xiaoyu Zhou Xiaofeng liu huai liu zhenya Ji Feng li School of Electrical and Automation Engineering Nanjing Normal UniversityNanjing 210023P.R.China

To facilitate the coordinated and large-scale participation of residential flexible loads in demand response(DR),a load aggregator(LA)can integrate these loads for *** this study,a residential DR optimization scheduling strategy was formulated considering the participation of flexible loads in ***,based on the operational characteristics of flexible loads such as electric vehicles,air conditioners,and dishwashers,their DR participation,the base to calculate the compensation price to users,was determined by considering these loads as virtual energy *** was quantified based on the state of virtual energy storage during each time ***,flexible loads were clustered using the K-means algorithm,considering the typical operational and behavioral characteristics as the cluster ***,the LA scheduling strategy was implemented by introducing a DR mechanism based on the directrix *** simulation results demonstrate that the proposed DR approach can effectively reduce peak loads and fill valleys,thereby improving the load management performance.

关键词： Residential demand response Flexible loads Load participation Load aggregator