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A model of low-frequency quasi-periodic oscillations in black hole X-ray binaries

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Research in Astronomy and Astrophysics 2012年第6期12卷 661-670页

作者： Zhi-Yun wang Chang-Yin Huang ding-xiong wang Jiu-Zhou wang School of Physics and Electronic Engineering Hubei University of Arts and Science Xiangyang441053 China School of Physics Huazhong University of Science and Technology Wuhan 430074 China School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan430074 China

A model of low-frequency quasi-periodic oscillations （LFQPOs） of black hole X-ray binaries （BHXBs） is proposed based on the perturbed magnetohydrody- namic equations of an accretion disk. It turns out that the LFQPO frequencies of some BHXBs can be fitted by the frequencies of the toroidal Alfv6n wave oscillation cor- responding to the maximal radiation flux. In addition, the positive correlation of the LFQPO frequencies with the radiation flux from an accretion disk is well interpreted.

关键词： accretion accretion disks -- black hole physics -- magnetic fields --stars: individual (XTE J1550-564 GRO J1655--40)

A magnetic reconnection model for quasi-periodic oscillations in black hole systems

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Research in Astronomy and Astrophysics 2013年第6期13卷 705-718页

作者： Chang-Yin Huang ding-xiong wang Jiu-Zhou wang Zhi-Yun wang School of Physics Huazhong University of Science and Technology School of Mathematics and Statistics Huazhong University of Science and Technology School of Physics and Electronic Engineering Hubei University of Arts and Science

The quasi-periodic oscillations （QPOs） in black hole （BH） systems with different scales are interpreted based on the magnetic reconnection of large-scale mag- netic fields generated by toroidal electric currents flowing in the inner region of the accretion disk, where the current density is assumed to be proportional to the mass density of the accreting plasma. The magnetic connection （MC） is taken into account in resolving dynamic equations describing the accretion disk, in which the MC be- tween the inner and outer disk regions, between the plunging region and the disk, and between the BH horizon and the disk are involved. It turns out that a single QPO frequency associated with several BH systems with different scales can be fitted by in- voking the magnetic reconnection due to the MC between the inner and outer regions of the disk, including the BH binaries XTE J1859＋226, XTE J1650-500 and GRS 1915＋105 and the massive BHs in NGC 5408 X-1 and RE J1034＋396. In addition, the X-ray spectra corresponding to the QPOs for these sources are fitted based on the typical disk-corona model.

关键词： accretion, accretion disks -- black hole physics -- magnetic fields --stars individual (XTE J1859+226, XTE J1650-500, GRS 1915+105) -- galaxies:individual (NGC 5408, RE J1034+396)

A magnetic model for low/hard state of black hole binaries

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Research in Astronomy and Astrophysics 2016年第3期16卷 33-42页

作者： Yong-Chun Ye ding-xiong wang Chang-Yin Huang Xiao-Feng Cao School of Physics Huazhong University of Science and Technology School of Physics and Optoelectronic Engineering Yangtze University School of Physics and Electronic Information Hubei University of Education

A magnetic model for the low/hard state （LHS） of two black hole X-ray binaries （BHXBs）, H1743-322 and GX 339-4, is proposed based on transport of the magnetic field from a companion into an accretion disk around a black hole （BH）. This model consists of a truncated thin disk with an inner advection-dominated accretion flow （ADAF）. The spectral profiles of the sources are fitted in agreement with the data observed at four different dates corresponding to the rising phase of the LHS. In addition, the association of the LHS with a quasi-steady jet is modeled based on transport of magnetic field, where the Blandford-Znajek （BZ） and Blandford-Payne （BP） processes are invoked to drive the jets from BH and inner ADAE It turns out that the steep radio/X-ray correlations observed in H 1743-322 and GX 339-4 can be interpreted based on our model.

关键词： accretion accretion disks -- black hole physics -- magnetic field-- stars: individual (H 1743- 322) -- stars: individual (GX 339-4)

Hyperaccretion after the Blandford-Znajek Process:A New Model for GRBs with X-Ray Flares Observed in Early Afterglows

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Chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 404-410页

作者： Wei-Hua Lei ding-xiong wang Yuan-Chuan Zou Lei Zhang Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We propose a three-stage model with Blandford-Znajek （BZ） and hyperaccretion process to interpret the recent observations of early afterglows of Gamma-Ray Bursts （GRBs）. In the first stage, the prompt GRB is powered by a rotating black hole （BH） invoking the BZ process. The second stage is a quiet stage, in which the BZ process is shut off, and the accretion onto the BH is depressed by the torque exerted by the magnetic coupling （MC） process. Part of the rotational energy transported by the MC process from the BH is stored in the disk as magnetic energy. In the third stage, the MC process is shut off when the magnetic energy in the disk accumulates and triggers magnetic instability. At this moment, the hyperaccretion process may set in, and the jet launched in this restarted central engine generates the observed X-ray flares. This model can account for the energies and timescales of GRBs with X-ray flares observed in early afterglows.

关键词： accretion, accretion disks - black hole physics - magnetic fields - gammarays bursts

A two-component jet model based on the Blandford-Znajek and Blandford-Payne processes

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Research in Astronomy and Astrophysics 2012年第7期12卷 817-828页

作者： Wei Xie Wei-Hua Lei Yuan-Chuan Zou ding-xiong wang Qingwen Wu Jiu-Zhou wang School of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics and Astronomy University of Nevada Las Vegas 4505 MarylandParkway Box 454002 Las Vegas NV89154-4002 USA

We propose a two-component jet model consistent with the observations of several gamma ray bursts （GRBs） and active galactic nuclei （AGNs）. The jet consists of inner and outer components, which are supposed to be driven by the Blandford- Znajek （BZ） and Blandford-Payne （BP） processes, respectively. The baryons in the BP jet are accelerated centrifugally via the magnetic field anchored in the accretion disk. The BZ jet is assumed to be entrained in a fraction of accreting matter leaving the inner edge of the accretion disk, and the baryons are accelerated in the conversion from electromagnetic energy to kinetic energy. By fitting the Lorentz factors of some GRBs （GRB 030329, GRB 051221A and GRB 080413B） and AGNs （Cen A, Mkn 501 and Mkn 421） with this model, we constrain the physical parameters related to the accretion and outflow of these two kinds of objects. We conclude that the spine/sheath structure of the jet from these sources can be interpreted naturally by the BZ and BP processes.

关键词： gamma rays: bursts -- galaxies: jets -- accretion accretion disks --magnetic fields -- jets and outflows

Extending the correlation of L_R-L_X to gamma-ray bursts

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Research in Astronomy and Astrophysics 2015年第5期15卷 617-622页

作者： Jing L Jing-Wen Xing Yuan-Chuan Zou Wei-Hua Lei Qing-Wen Wu ding-xiong wang GXU-NAOC Center for Astrophysics and Space Sciences Department of PhysicsGuangxi University Guangxi Key Laboratory for Relativistic Astrophysics School of Physics Huazhong University of Science and Technology

The well-known correlation between radio luminosity （LR） and X-ray luminosity （Lx）, LR/LX 10^-5, holds for a variety of objects, such as active galactic nuclei, Galactic black holes, solar flares and cool stars. Here we extend the relation to gamma-ray bursts （GRBs） and find that the GRBs also obey a similar LR - LX relation, with a slightly different slope of LR ∝ LX^1.1. This relation implies that the explosions that occur on different scales may have a common underlying origin.

关键词： gamma-ray bursts general -- quasars general -- stars black holes

A Magnetic Model for Low/Hard States Associated with Jets in Black Hole X-Ray Binaries

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International Journal of Astronomy and Astrophysics 2012年第3期2卷 156-166页

作者： ding-xiong wang Jiu-Zhou wang Zhao-Ming Gan Chang-Yin Huang School of Physics Huazhong University of Science and Technology Wuhan China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China

A model for the low/hard (LH) state associated with a steady jet in black hole X-ray binaries (BHXBs) is proposed based on disc-corona model with open magnetic fields trapped in magnetic patches, which arises from ‘flux expulsion’ effect of convective turbulence. We fit the spectral profiles of the LH state for the BHXBs, 4U 1543-475, GX 339-4, XTE J1550-564 and GRO J1655-40, and fit the relation between jet power and X-ray luminosity dynamically in the LH state by adjusting accretion rate and the outer boundary of the corona over the disc.

关键词： Accretion Accretion Disks Black Hole Physics X-Rays Binaries Magnetic Fields

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan xiong Xin wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

蛇床子素对大鼠视网膜缺血再灌注损伤的防护作用及机制研究

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解放军药学学报 2016年第4期32卷 311-313,317页

作者：丁熊刘辉王平三峡大学第2临床医学院仁和医院眼科湖北宜昌443000

目的探讨蛇床子素对视网膜缺血-再灌注损伤的作用及其潜在机制。方法大鼠腹腔注射蛇床子素(20、40、80 mg·kg^(-1))0.5 h后采用前房灌注升高眼压的方法构建大鼠缺血-再灌注损伤模型。通过观察各组视网膜厚度,视网膜电图b波振幅,肿瘤坏... 详细信息

目的探讨蛇床子素对视网膜缺血-再灌注损伤的作用及其潜在机制。方法大鼠腹腔注射蛇床子素(20、40、80 mg·kg^(-1))0.5 h后采用前房灌注升高眼压的方法构建大鼠缺血-再灌注损伤模型。通过观察各组视网膜厚度,视网膜电图b波振幅,肿瘤坏死因子、单核细胞趋化蛋白和白细胞介素,丙二醛,过氧化氢酶、谷胱甘肽过氧化物酶和超氧化物歧化酶的水平评估蛇床子素对大鼠视网膜缺血-再灌注损伤的作用。结果蛇床子素呈剂量依赖性降低丙二醛、肿瘤坏死因子、单核细胞趋化蛋白和白细胞介素的水平,但增加视网膜厚度、视网膜电图b波振幅以及过氧化氢酶、谷胱甘肽过氧化物酶和超氧化物歧化酶水平。结论蛇床子素通过减轻炎症和氧化应激而减轻视网膜缺血-再灌注损伤。

关键词：蛇床子素视网膜缺血再灌注损伤炎症氧化应激