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Multicolor Optical Monitoring of the γ-Ray Emitting Narrow-line Seyfert 1 Galaxy PMN J0948+0022 from 2020 to 2021

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Research in Astronomy and Astrophysics 2022年第7期22卷 60-72页

作者： Yu-Xin Xin ding-rong xiong Jin-Ming Bai Hong-Tao Liu Kai-Xing Lu Ji-rong Mao Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China

In order to study the physical properties of the γ-ray emitting narrow-line Seyfert 1(NLS1) galaxy population,photometric and spectral observations of the γ-ray emitting NLS1 PMN J0948+0022 were made with the Lijiang2.4 m optical telescope of Yunnan Observatories,Chinese Academy of *** data in the B and R bands were collected for 50 nights from 2020 January to 2021 *** the observation epoch,the variability amplitudes are 73.67% in the B band and 79.96% in the R ***-day variability is found in two observation nights,and the duty cycle value is 29% with variability amplitude> 12.9% in the R band,which support the presence of the relativistic jets in the *** redder-when-brighter(RWB) chromatic trend(or steeper-when-brighter trend) appears on intra-day and long *** RWB trend is dominated by the radiation of accretion disk and jet,and resembles those in flat spectrum radio *** PMN J0948+0022 is brighter than 17.5 in the R band,there is no color change *** analyzing the spectral data of PMN J0948+0022,we obtained the black hole mass of M.=1.61×10^(7) Mand accretion rate of M=93,and confirmed that PMN J0948+0022 is a super-Eddington accreting *** redshifts of reverberation mapped super-Eddington accreting active galactic nuclei can be expanded by PMN J0948+0022 up to above ***-Eddington accreting NLS1 galaxies were chosen as a new type of cosmological candle in the *** J0948+0022 may be used as a target for the next step of reverberation mapping monitoring project of super-Eddington accreting massive black holes.

关键词： galaxies:jets galaxies:photometry galaxies:Seyfert galaxies:active

The photometric monitoring of γ-ray-loud narrow-line Seyfert 1 galaxy 1H0323+342 from 2006 to 2010

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Research in Astronomy and Astrophysics 2017年第7期17卷 47-56页

作者： Fang Wang ding-rong xiong Jin-Ming Bai Shao-Kun Li Jian-Guo Wang Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Center for Astronomical Mega-Science Chinese Academy of Sciences

1H 0323＋342 is a γ-ray-loud narrow-line Seyfert 1 galaxy（NLS1）. The variability mechanism of γ-ray-loud NLS1 s remains unclear. We have observed 1H 0323＋342 photometrically from 2006 to2010 with a total of 41 nights of observations in order to constrain the variability mechanism. Intraday variabilities（IDVs） are detected on four nights. When considering the nights with time spans 〉 2 hours,the duty cycle is 28.3%. The average variability amplitude is 10.8% for IDVs and possibly variable nights. In the color-magnitude diagram, there are bluer-when-brighter chromatic trends for intraday and long-term timescales, which could be explained by the shock-in-jet model, and also could possibly be due to two distinct components or an accretion disk model.

关键词： galaxies active - galaxies individual (1H 0323+342)- galaxies jets

Optical multi-color monitoring of OJ 287 from 2006 to 2012

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Research in Astronomy and Astrophysics 2017年第8期17卷 57-68页

作者： Qian Guo ding-rong xiong Jin-Ming Bai Xu-Liang Fan Wei-Min Yi Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China

We present our optical multi-color monitoring of the BL Lac object OJ 287 from January 2006to December 2012 in the V,R and I bands.A relatively active state in OJ 287 has been found over all monitored epochs,among which the variations of average magnitude in V/R/I bands were measured with ?V=1.956 mag,?R=2.067 mag and ?I=2.115 mag,*** reliable intraday variability is detected,but possible variability is detected on 16 *** relative variation amplitudes fall into the range between 1% and 8%,with the majority between 2% and 4%.No time lags have been detected,but strong correlations exist among light curves in the three *** bluer-when-brighter trend is dominant over intraday timescales,which supports the shock-in-jet *** combining with additional V/R band data obtained from SMARTS and the Steward Observatory,we also find a bluer-when-brighter trend over a long-term *** possible periods of 513,176,36,30,26,17 and 14 d are found in all time-series data sets from 2006 to *** explanations about these periods are given.

关键词： BL Lacertae objects individual(OJ 287)—galaxies active—galaxies photometry

YFPOL: A Linear Polarimeter of Lijiang 2.4 m Telescope

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Research in Astronomy and Astrophysics 2022年第9期22卷 10-34页

作者： Yu-Xin Xin Jin-Ming Bai Zhong-Quan Qu Zhi Xu Ji-rong Mao Kai Ye Bao-Li Lun Xu ding Hong-Tao Liu Yue Zhong Yu-Feng Fan Xiao-Guang Yu Liang Xu Xiao-Bo Dong Jian-Guo Wang ding-rong xiong Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China

Polarimetry plays an important role in investigating physical properties for celestial objects. We present a polarimeter named YFPOL for the Cassegrain focus of the Lijiang 2.4 m Telescope(LJT) of Yunnan Observatories, Chinese Academy of Sciences. YFPOL is a traditional single-beam polarimeter with a rotating polarizer. As the focal-reducer instrument Yunnan Faint Object Spectrograph and Camera(YFOSC) is always positioned on the Cassegrain focal plane of LJT, we develop two sets of ultra-thin(thickness ding using the unpolarized domeflat, when the Cassegrain rotation angle is the same or nearest to that of the polarization observation. We develop a quasiautomatic pipeline for YFPOL and its effectiveness has been verified by tests of the polarimetric observation with blazar S5 0716+714. The calibration is performed by observing the zero-polarized and highly-polarized standard stars. We successfully reach high precision polarization in the 7’ field of view, and the systematic uncertainty is below 0.8% for a V = 11.68 target with a 10 s exposure. The instrument polarization angle offset is 2°. 6. YFPOL is not only a simple polarimeter, but also a spectropolarimeter with grisms that can be considered in the future.

关键词： polarization instrumentation:polarimeters techniques:image processing techniques:polarimetric

Astronomical Site Monitoring System at Lijiang Observatory

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Research in Astronomy and Astrophysics 2020年第9期20卷 291-308页

作者： Yu-Xin Xin Jin-Ming Bai Bao-Li Lun Yu-Feng Fan Chuan-Jun Wang Xiao-Wei Liu Xiao Guang Yu Kai Ye Teng-Fei Song Liang Chang Shou-Sheng He Jji-rong Mao Liang Xu ding-rong xiong Xi-Liang Zhang Jian-Guo Wang Xu ding Hai-Cheng Feng Xiang-Kun Liu Yang Huang Bing-Qiu Chen Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Sciences Chinese Academy of SciencesBeijing 100101China South-Western Institute for Astronomy Research Yunnan UiversityKunming 650500China

We installed two sets of Astronomical Site Monitoring Systems(ASMSs)at Lijiang Observatory(GMG),for the running of the 2.4-meter Lijiang optical telescope(LJT)and the 1.6-meter Multi-channel Photometric Survey Telescope(Mephisto).The Mephisto is under *** ASMS has been running on robotic mode since *** core instruments:Cloud Sensor,All-Sky Camera and AutonomousDIMM that are developed by our group,together with the commercial Meteorological Station and Sky Quality Meter,are combined into the astronomical optical site monitoring *** new Cloud Sensor's Cloud-Clear Relationship is presented for the first time,which is used to calculate the All-Sky cloud *** designed the Autonomous-DIMM located on a tower,with the same height as *** seeing data have been observed for a full ***'s data for the year 2019 are also analysed in detail,which are valuable to observers.

关键词： Astronomical Site Monitoring System Lijiang Observatory Cloud Sensor Autonomous-DIMM

Lijiang 2.4-meter Telescope and its instruments

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Research in Astronomy and Astrophysics 2019年第10期19卷 95-108页

作者： Chuan-Jun Wang Jin-Ming Bai Yu-Feng Fan Ji-rong Mao Liang Chang Yu-Xin Xin Ju-Jia Zhang Bao-Li Lun Jian-Guo Wang Xi-Liang Zhang Mei Ying Kai-Xing Lu Xiao-Li Wang Kai-Fan Ji ding-rong xiong Xiao-Guang Yu Xu ding Kai Ye Li-Feng Xing Wei-Min Yi Liang Xu Xiang-Ming Zheng Yuan-Jie Feng Shou-Sheng He Xue-Li Wang Zhong Liu Dong Chen Jun Xu Song-Nian Qin Rui-Long Zhang Hui-Song Tan Zhi Li Ke Lou Jian Li Wei-Wei Liu Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Astrophysics Center of Guangzhou University Guangzhou 510006China

The Lijiang 2.4-meter Telescope(LJT), the largest common-purpose optical telescope in China,has been available to the worldwide astronomical community since 2008. It is located at the Gaomeigu site,Lijiang Observatory(LJO), in the southwest of China. The site has very good observational *** its 10-year operation, several instruments have been equipped on the LJT. Astronomers can perform both photometric and spectral observations. The main scientific goals of LJT include recording photometric and spectral evolution of supernovae, reverberation mapping of active galactic nuclei, investigating the physical properties of binary stars and near-earth objects(comets and asteroids), and identification of exoplanets and all kinds of transients. Until now, the masses of 41 high accretion rate black holes have been measured, and more than 168 supernovae have been identified by the LJT. More than 190 papers related to the LJT have been published. In this paper, the general observation conditions of the Gaomeigu site is introduced at first. Then, the structure of the LJT is described in detail, including the optical, mechanical, motion and control system. The specification of all the instruments and some detailed parameters of the YFOSC is also presented. Finally, some important scientific results and future expectations are summarized.

关键词： telescopes Lijiang 2.4-m Telescope-instrumentation photometers-instrumentation spectrographs

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

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei xiong Xuan Ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

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航空电子系统SCI网络可靠性建模研究

系统工程与电子技术 2004年第10期26卷 1526-1528页

作者：姜震邵定蓉熊华钢汪健甄北京航空航天大学电子信息工程学院北京100083 中航第一集团第六一三研究所河南洛阳471009

针对航空电子系统对网络互连技术有严格实时要求的特点,首先建立了可扩展一致性接口(scalableco herentinterface,SCI)网络中的任务模型,然后通过在网络系统可靠性模型引入时间权函数建立了基于实时任务的SCI网络可靠性模型,得出了系统... 详细信息

针对航空电子系统对网络互连技术有严格实时要求的特点,首先建立了可扩展一致性接口(scalableco herentinterface,SCI)网络中的任务模型,然后通过在网络系统可靠性模型引入时间权函数建立了基于实时任务的SCI网络可靠性模型,得出了系统的可靠性矩阵,最后针对联合先进攻击技术(JAST)航空电子结构中SCI蝶型网络给出了建模实例。

关键词：航空电子系统可扩展一致性接口网络可靠性