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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

Resonant cyclotron scattering in pulsar magnetospheres and its application to isolated neutron stars

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Research in Astronomy and Astrophysics 2010年第6期10卷 553-568页

作者： Hao Tong Ren-Xin Xu Qiu-He Peng li-ming song Department of Astronomy Nanjing University Nanjing 210093 China Department of Astronomy Peking University Beijing 100871 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Resonant cyclotron scattering （RCS） in pulsar magnetospheres is considered. The photon diffusion equation （Kompaneets equation） for RCS is derived. The photon system is modeled three dimensionally. Numerical calculations show that there exist not only up scattering but also down scattering of RCS, depending on the parameter space. RCS＇s possible applications to spectral energy distributions of magnetar candidates and radio quiet isolated neutron stars （INSs） are pointed out. The optical/UV excess of INSs may be caused by the down scattering of RCS. The calculations for RX J1856.5-3754 and RX J0720.4-3125 are presented and compared with their observational data. In our model, the INSs are proposed to be normal neutron stars, although the quark star hypothesis is still possible. The low pulsation amplitude of INSs is a natural consequence in the RCS model.

关键词： radiation mechanism nonthermal -- scattering -- stars neutron -- pulsars general -- pulsars individual (RX J1856.5-3754, RX J0720.4-3125)

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

Synthesis and Crystal Structure of 5-N-i-Propyl-2-(2′-nitrobenzenesulfonyl)-glutamine

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Chemical Research in Chinese Universities 2006年第6期22卷 760-762页

作者： XIAO Yong-jun WANG Jian-guo WANG Bao-lei li Zheng-ming song Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

The title compound, 5 -N-i-propyl-2-（2＇ -nitrobenzenesulfonyl）-glutamine, was synthesized and its structure was confirmed by IB, MS, ^1H NMB, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2（ 1 ）, with a =0. 69281 （ 11 ） nm, b = 0. 76508（12）, c = 1. 5843（3） nm, α=90°, β =90. 941 （3）°, γ =90°, V=0. 8397（2） nm^3, Z =-2, Dc = 1.477 g/cm^3,μ =0. 236 mm^-1, F（000） =392, R =0. 0297, and wR=0.0664.

关键词： 5 -N-i-Propyl-2-( 2' -nitrobenzenesulfonyl) -glutamine Synthesis Crystal structure

A Study on the Correlations between the Twin kHz QPO Frequencies in Sco X-1

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Chinese Journal of Astronomy and Astrophysics 2005年第6期5卷 595-600页

作者： Hong-Xing Yin Cheng-Min Zhang Yong-Heng Zhao li-ming song Fan Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039

For the bright neutron star low-mass X-ray binary Sco X-l, we analyzed all updated frequencies of the twin kilohertz quasi-periodic oscillations （kHz QPOs）, their correlations and distributions. We found that the frequency separation of the kHz QPO peaks appears not to be a constant, rather, it decreases with increasing inferred mass accretion rate. We show that the currently available data of Sco X-1 by Rossi X-ray Timing Explorer are inconsistent with the proposals of the beat model that the frequency separation is a constant. Our conclusions are consistent with those of some previous researchers and we discuss further implications for the kilohertz QPO models.

关键词： X-rays accretion disks - stars neutron - X-rays stars