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Astrometry of three near Earth asteroids with the Lijiang 2.4 m telescope

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Research in Astronomy and Astrophysics 2015年第3期15卷 435-442页

作者： Xi-Liang Zhang Yong Yu Xue-Li wang chuan-jun wang Liang Chang Yu-Feng Fan Zheng-Hong Tang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences

Under the framework of observational campaigns organized by the GAIA Follow Up Network for Solar System Objects, three near Earth asteroids, 367943 Duende, 99942 Apophis and 2013 TV135, were observed with the Lijiang 2.4m telescope administered by Yunnan Observatories. The software package PRISM was used to calibrate the CCD fields and measure the positions of 99942 Apophis and 2013 TV135, and our own software was used for 367943 Duende. A comparison of the results show that the ephemerides of INPOP10a and JPL are consistent for 99942 Apophis and 2013 TV135, however, they are quite inconsistent for 367943 Duende. Moreover, we have found that differences between the mean values in the ephemerides of INPOP10a and JPL are about 72＂ and -199＂ in right ascension and declination respectively for 367943 Duende. Moreover, the ephemeris published by JPL is reliable in terms of the mean observed-minus-calculated （O - C） residuals in right ascension and declination of about 2.72＂ and 1.49＂ respectively.

关键词： astrometry -- near Earth objects -- astrometric observation --ephemerides

Controlled synthesis of monodispersed spherical ruthenium powders

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Rare Metals 2023年第12期42卷 4246-4254页

作者： Feng-Shuo Xu Hao Cui Man-Men Liu Jia-Lin Chen Ming Wen chuan-jun wang Wei wang Song Li Xu-Dong Sun Shao-Hong Liu Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Yunnan Precious Metals Laboratory Co.Ltd.Kunming 650106China

Monodispersed spherical Ru powders are essential for fabricating high-performance Ru sputtering targets,which have applications in very-large-scale integration circuits and magnetic recording ***,the synthesis of such powders remains a major ***,we reported the synthesis of monodispersed spherical Ru powders through controlling the molar ratio of SO_(4)^(2-)to Ru^(3+)in urea homogeneous precipitation solution and the annealing *** the addition of(NH4)2SO_(4)into the reaction solution,only gel-like precipitation particles were *** introducing(NH_(4))_(2)SO_(4) into the reaction solution and controlling the molar ratio of SO_(4)^(2-)to Ru3+between 0.50 and 1.00,monodispersed spherical precursor powders were *** nucleation and growth of monodispersed spherical precursor particles in solution were found to conform to LaMer's *** controlled annealing at 450℃in a hydrogen atmosphere,the obtained metallic Ru powder with an average particle size of 135 nm inherited the spherical morphology and excellent dispersity from the monodispersed spherical precursor *** results and findings would deepen the understanding of the preparation of monodispersed Ru and Ru-like powders.

关键词： Ruthenium Sputtering target Spherical powder Integration circuits Magnetic recording

Quality Control of YFOSC Data I. The On-site Quick Analysis System

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Research in Astronomy and Astrophysics 2023年第3期23卷 119-127页

作者： Jian-Guo wang Jin-Ming Bai Ying-He Zhao Xiao-Bo Dong Kai-Xing Lu chuan-jun wang Ju-Jia Zhang Yu-Xin Xin Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan ObservatoriesKunming 65001lChina

The Lijiang 2.4 m Telescope(LJT)is one of the most important telescopes for general astronomical observations in *** Faint Object Spectrograph and Camera(YFOSC)is a widely used instrument mounted on the LJT,which occupies for~80%of the observing time of the LJT,and thus instrument health and data quality of the YFOSC are very important for both the telescope maintenance team and users of the *** we develop an automated data analysis system for the quality control(QC)of YFOSC *** system is also a new function of the observing support of the *** on the system,YFOSC data can be reduced quickly as they are acquired and QC parameters are *** can assess the quality of their data and make a possible revision of their observing plan in *** parameters can also be used to check the health of the YFOSC,which is helpful for the telescope maintenance team to find potential *** of these aim at improving the productivity of the LJT.

关键词： Quick Observer YFOSC

Rapid instrument exchanging system for the Cassegrain focus of the Lijiang 2.4-m Telescope

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Research in Astronomy and Astrophysics 2015年第6期15卷 918-928页

作者： Yu-Feng Fan Jin-Ming Bai Ju-Jia Zhang chuan-jun wang Liang Chang Yu-Xin Xin Rui-Long Zhang 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

As a facility used for astronomical research, the Lijiang 2.4-m telescope of Yunnan Astronomical Observatories, requires the ability to change one auxiliary instrument with another in as short a time as possible. This arises from the need to quickly respond to scientific programs （e.g. transient observation, time domain studies） and changes in observation conditions （e.g. seeing and weather conditions）. In this paper, we describe the design, construction and test of hardware and software in the rapid instrument exchange system （RIES） for the Cassegrain focal station of this telescope, which enables instruments to be quickly changed at night without much loss of observing time. Tests in the laboratory and at the telescope show that the image quality and pointing accuracy of RIES are satisfactory. With RIES, we observed the same Landolt standard stars almost at the same time with the Princeton Instruments VersArray 1300B Camera （PICCD） and the Yunnan Faint Object Spectrograph and Camera （YFOSC）, while both were mounted at the Cassegrain focus. A quasi-simultaneous comparison shows that the image quality of the optical system inside the YFOSC is comparable with that provided by the PICCD.

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

Substrate participation ultrafast synthesis of amorphous NiFe nanosheets on iron foam at room temperature toward highly efficient oxygen evolution reaction

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Journal of Energy Chemistry 2019年第8期28卷 197-203,I0007页

作者： Xiao Yang Qian-Qian Chen chuan-jun wang Chun-Chao Hou Yong Chen Key Laboratory of Photochemical Conversion and Optoelectronic Materials & HKU-CAS Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China College of Chemistry and Material Science Shandong Agricultural UniversityTai'an 271018 Shandong China

The earth-abundant transition metal based nanomaterials are regarded as state-of-the-art oxygen evolution reaction(OER) electrocatalyst. Recent studies have shown that amorphous materials are more active than their crystalline forms. Herein, we demonstrate a facile and rapid substrate participation method to fabricate amorphous NiFe nanosheets on iron foam(a-NiFe NS/IF) at ambient temperature as a highly efficient electrocatalyst for OER. This method only takes 200 s to fabricate the a-NiFe NS/IF and the electrocatalyst possesses excellent catalytic activities which only needs overpotentials of about 211 and 240 m V to reach 10 and 100 mA cm-2 current densities in 1.0 M KOH.

关键词： Electrocatalytic water oxidation Fast fabrication Amorphous nanomaterials NiFe nanosheets

The Coude Echelle Spectrograph for the Lijiang 1.8 m telescope

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Research in Astronomy and Astrophysics 2020年第3期20卷 76-83页

作者： Xiao-Li wang Liang Chang Lei wang Hang-Xin Ji Hao Xian Zhen Tang Yu-Xin Xin chuan-jun wang Shou-Sheng He Ju-Jia Zhang Bao-Li Lun Kai Wei Xi-Qi Li Xiao-jun Jiang Hui-Juan wang Hong-Bin Li Ji-Rong Mao Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China The Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of ScienccsBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The Coude Echelle Spectrograph(CES)was originally mounted on Xinglong 2.16 m telescope in *** the High Resolution Fiber-fed Spectrograph(HRS)was commissioned at Xinglong 2.16 m telescope,the red path of CES was moved to Lijiang 1.8 m telescope,following some redesign and *** CES of Lijiang 1.8 m telescope has the spectral resolution(R=λ/?λ)ranging from 20000 to 50000 corresponding to different slit *** a 2 k×2 k PI CCD,CES has a wavelength coverage between 570 nm to 1030 *** particular,the resolution of 37000 at 0.5 mm slit corresponds to 1.3′′on the *** limiting magnitude is V=11.5 with the use of the tip-tilt feedback system,and the S/N is about 40 for 1 hour exposure at 600 nm(R=37000).During the installation of CES,the tip-tilt mirror technology had successfully fulfilled high precision guiding and tracking for high resolution spectral observation and significantly improved the observation efficiency.

关键词： Instrumentation:spectrographs methods:observational techniques:spectroscopic

CALCULATION OF TURBULENT FLOW AND PREMIXED COMBUSTION IN A 2-D SUDDEN EXPANSION CHANNEL

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Chinese Journal of Aeronautics 1993年第4期 244-252页

作者： Xu Cheng-gang,Yan chuan-jun,wang Hong-ji (Northwestern Polytechnical University,Xi’an,China,710072)

The random vortex method is used to model turbulent flow and premixed combustionin a 2-D sudden expansion channel. The averaged and instantaneous velocity fields arepresented. In contrast with averaged velocity field, more than one large-scale vortex appearsin the instantaneous velocity field. Owing to the interaction between theselarge-scale vortexes, the length of recirculating flow region changes periodically about theaveraged value. The calculation of premixed combustion shows that these large-scale vortexstructures play an important role in the distribution of flame front in the flow field.

关键词： CALCULATION OF TURBULENT FLOW AND PREMIXED COMBUSTION IN A 2-D SUDDEN EXPANSION CHANNEL length

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