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Research in Astronomy and Astrophysics 2024年第6期24卷 225-233页

作者： Xue-Feng Lu li-ming song ming-Yu Ge Shuang-Nan Zhang Jin-Lu Qu Ce Cai Cong-Zhan liu Cheng-Kui li Yu-Cong Fu Ying-Chen Xu Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Department of Astronomy Beijing Normal UniversityBeijing 100875China

In October 2022,the magnetar SGR J1935+2154 entered the active outburst *** the episode,the InsightHXMT satellite carried out a long observation that lasted for 20 *** than 300 bursts were detected,and a certain amount of persistent radiation signals were also *** paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT *** the same time,the burst phase distribution characteristics,spectral lag results of burst,the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are *** found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+*** observed zero-lag burst does not have a unique *** time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the *** also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile.

关键词： radiation mechanisms:general dense matter magnetic fields

Timing and Spectral Analysis of the Black Hole X-Ray Binary MAXI J1803-298 with Insight-HXMT Data

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Research in Astronomy and Astrophysics 2024年第6期24卷 209-224页

作者： Ying-Chen Xu Jin-Lu Qu MMéndez Rui-Can Ma Long Ji liang Zhang Yue Huang Qing-Cui Bu li-ming song Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Kapteyn Astronomical Institute University of GroningenP.O.BOX 8009700 AV GroningenThe Netherlands Dongguan Neutron Science Center Dongguan 523808China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Institut für Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitätSand 1D-72076 TübingenGermany

We present a comprehensive analysis of the 2021 outburst of MAXI J1803–298 utilizing observations of the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)spanning from the low hard state to the high soft *** the Insight-HXMT data set,compared to the previous work,we identify a more prolonged presence of typeC quasi-periodic oscillations(QPOs)with centroid frequencies ranging from~0.16 to 6.3 Hz,which present correlations with the hardness ratio and the photon index of the Comptonized *** QPO frequencies less than~2 Hz,the QPO phase lags are hard(photons of 10–19 keV arrive later than those of 1–4 keV),while at higher frequencies,the lags become soft at and above~4 ***,the spectra in all Insight-HXMT observations consist of a multi-color blackbody component and a Comptonized component,as commonly observed in classical black hole X-ray *** analyze state transitions and the evolution of accretion geometry in this *** fitted inner disk radius increases abnormally during the low hard state,hypothesized to result from the corona condensing onto the inner ***,two significant drops in flux are observed during the soft intermediate state,maybe implying changes in the corona/jet and the disk,respectively.

关键词： X-rays:binaries accretion accretion disks stars:black holes

Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu Zhang Shao-lin Xiong Ji-Rong Mao Shuang-Nan Zhang Wang-Chen Xue Chao Zheng Jia-Cong liu Zhen Zhang Xi-Lu Wang ming-Yu Ge Shu-Xu Yi li-ming song Zheng-Hua An Ce Cai Xin-Qiao li Wen-Xi Peng Wen-Jun Tan Chen-Wei Wang Xiang-Yang Wen Yue Wang Shuo Xiao Fan Zhang Peng Zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

Effect of the microstructure of Al 7050-T7451 on anodic oxide formation in sulfuric acid

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 432-438页

作者： Jian-hua liu ming li song-mei li Min Huang School of Materials Science and Engineering Beihang University Beijing 100083 China

The effect of the microstructure of an Al 7050-T7451 substrate on the anodic oxide formation in sulfuric acid was studied in this article. The microstructure of the substrate was assessed by optical microscope （OM） and transmission electron microscope （TEM）. The surface and cross-section morphologies of the oxide films were examined by scanning electron microscope （SEM）. The chemical composition of intermetallic particles in the alloys and films was investigated using energy dispersive spectroscope （EDS）. The roles of intermetallic phases and grain or subgrain boundaries on the oxide film formation were researched using the potentiodynamic and potentiostatic polarization technique in sulfuric acid solution. The results show that the transition of coarse intermetallic particles or grain （subgrain） boundaries at the surface of Al alloys can be characterized by potentiodynamic polarization curves. The surface and cross-section micrographs of the anodic layer seem to preserve the microstructure of the substrate. Large cavities in the anodic films are caused by the preferential dissolution of coarse AItCuMg particles and the entrance of Cu-rich remnants into the electrolyte during anodizing. The Al7Cu2Fe particles tend to be occluded in the oxide layer or lose from the oxide surface because of peripheral trenching. Small pores in the films are induced by the dissolution of precipitates in grain or subgrain boundaries. The film surface of recrystallized grain bodies is smooth and homogeneous.

关键词： aluminum alloys anodic oxide intermetallic particles grain boundaries

Synthesis, Crystal Structure and Biological Activity of 2-Chloro-N-{2-fluoro-5-[N-(phenylsulfonyl) phenyl-sulfonamido]phenyl}benzamide

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Chemical Research in Chinese Universities 2008年第3期24卷 295-298页

作者： li Wen-ming WANG Jian-guo li Zheng-ming song Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry National Pesticide Engineering Research Center Nankai University Tianjin 300071 P R. China

2-Chloro-N-{2-fluoro-5-[N-（phenylsulfonyl）phenylsulfonamido]phenyl}benzamide was synthesized and its crystal structure was also determined by X-ray single-crystal diffraction. The title compound（C25H18ClFN2O5S2） belongs to monoclinic, space group P21/n with a=0.7377（3） nm, b=1.2036（5） nm, c=2.6846（11） nm, β=90.895（9）°, V=2.3833（16） nm3, Mr=544.98, Z=4, Dc=1.519 g/cm3, μ=0.385 mm–1, F（000）=1120, R1=0.0632, and wR2=0.1438. Its crystal structure belongs to a novel class that has not been reported yet, and its preliminary herbicidal activity was also tested. Its inhibition rate to seedling growth of barnyard grass reaches 15.1% at 100 μg/mL.

关键词： X-ray diffraction Crystal structure Synthesis Biological activity

The optical/ultraviolet excess of isolated neutron stars in the resonant cyclotron scattering model

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Research in Astronomy and Astrophysics 2011年第12期11卷 1371-1376页

作者： Hao Tong Ren-Xin Xu li-ming song Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China

X-ray dim isolated neutron stars are peculiar pulsar-like objects, characterized by their Planck-like spectrum. In studying their spectral energy distributions, optical/ultraviolet （UV） excess is a long standing problem. Recently Kaplan et al. measured the optical/UV excess for all seven sources, which is understandable in the resonant cyclotron scattering （RCS） model previously addressed. The RCS model calculations show that the RCS process can account for the observed optical/UV excess for most sources. The flat spectrum of RX J2143.0＋0654 may be due to contributions from the bremsstrahlung emission of the electron system in addition to the RCS process.

关键词： pulsars: individual (RX J0420.0-5022 RX J0720.4-3125 RX J0806.4-4123 RX J1308.6+2127 RX J1605.3+3249 RX J1856.5-3754 RX J2143.0+0654)-- stars: neutron

Synthesis and Crystal Structure of a Sodium Monosulfuron-ester (N-[2'-(4-Methyl)pyrimidinyl]-2-carbomethoxy Benzyl Sulfonylurea Sodium)

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1414-1417页

作者： KOU Jun-Jie li Zheng-ming song Hai-Bin National Pesticide Engineering Research Center State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

Monosulfuron-ester is a novel sulfonylurea herbicide with ultra-low dosage Herein sodium monosulfuron-ester was synthesized and its crystal structure was determined by X-ray diffraction method. The title compound belongs to monoclinic, space group P21/c with a = 9.335（5）, b = 20.632（12）, c = 13.853（8） A, β = 107.193（9）°, Mr = 487.46, Z = 4, Dc = 1.270 g/cm^3, μ = 0.293 mm^-1, F（000） = 1015, R = 0.0859 and wR = 0.2633. In the title compound, Na coordinates with N（1）, O（1） and O（3） from one monosulfuron-ester molecule, N（4A） and O（5A） from the other monosulfuron-ester molecule and one oxygen atom from DMSO to give six coordination bonds.

关键词： sulfonylurea sodium monosulfuron-ester crystal structure

Insight-HXMT observations of the Crab pulsar

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Research in Astronomy and Astrophysics 2019年第6期19卷 109-116页

作者： You-li Tuo ming-Yu Ge li-ming song lin-li Yan Qing-Cui Bu Jin-Lu Qu Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of the Chinese Academy of Sciences Beijing 100049 China School of Mathematics and Physics Anhui Jianzhu University Hefei 230601 China

We report on X-ray emission properties of the Crab pulsar(PSR B0531+21) using observations by Insight-HXMT during its first year after launch. We obtained high signal-to-noise profiles in the X-ray energy band 11–250 keV. We have confirmed an increase in the flux ratio of the second peak over the main peak with increasing energy, consistent with other missions. The separation of the two peaks shows no significant trend with increasing energy. The phase-averaged spectrum, fitted by a logpar model, and the phase-resolved spectra of the Crab pulsar, fitted by a powerlaw in the different energy bands of HXMT, are consistent with RXTE and NuSTAR in that photon indices evolve as a function of phase as well as a function of energy, contributing to a broadband modeling.

关键词： stars neutron star-pulsars individual(Crab)-X-rays

Synthesis and Crystal Structure of N-[4-(4-Methyl-phenylsulfamoyl)-phenyl]- 4-methyl-1,2,3-thiadiazole-5-carboxamide

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Chinese Journal of Structural Chemistry 2007年第5期26卷 501-504页

作者： WANG Jian-Guo XIAO Yong-Jun li Zheng-ming song Hai-Bin （Elemento-organic Chemistry hlstitute State Key Laboratory ofElemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of the title compound （C17H16N4O3S2, Mr = 388.46） has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 13.688（2）, b = 16.704（3）, c = 8.3308（12）A, β = 99.474（6）°, V = 1878.8（5） A^3, Mr = 388.46, Z = 4, Dc = 1.373 g/cm3, μ = 0.308 mm^–1, F（000） = 808, R = 0.0389 and wR = 0.0917. X-ray analysis reveals that the crystal structure involves intermolecular N–H…O and N–H…N hydrogen bonds, which link the molecules into a layer parallel to the ac plane.

关键词： X-ray diffraction crystal structure synthesis

Synthesis and Crystal Structure of 1-[4-(Pyrimidin-2-yl)piperazin-1-ylmethyl]-1H-benzotriazole

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Chinese Journal of Structural Chemistry 2006年第5期25卷 543-546页

作者： HE Feng-Qi WANG Bao-Lei li Zheng-ming song Hai-Bin Elemento-organic Chemistry Institute State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

The crystal structure of the title compound （C15H17N7, Mr = 295.36） has been determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1^- with a = 6.370（2）, b = 9.830（3）, c = 11.821（4） A, α = 89.603（6）, β = 86.018（6）, γ = 85.850（6）°, V = 736.5（4） A^3, Z= 2, F（000） = 312, Dc = 1.332 g/cm^3, μ = 0.087 mm^-1, the final R = 0.0476 and wR = 0.1079 for 1494 observed reflections with Ⅰ 〉 2σ（Ⅰ）. X-ray analysis reveals that the piperazine ring of the title compound is in a chair conformation. In addition, in the crystal structure there also exist intramolecular C-H…N hydrogen bonds and intermolecular π-π interactions between benzotriazole rings.

关键词： X-ray diffraction crystal structure synthesis