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The FAST all sky HI survey(FASHI):The first release of catalog

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 112-133页

作者： Chuan-Peng Zhang Ming Zhu Peng Jiang Cheng Cheng Jing Wang Jie Wang Jin-Long Xu xiao-lan liu Nai-Ping Yu Lei Qian Haiyang Yu Mei Ai Yingjie Jing Chen Xu Ziming liu Xin Guan Chun Sun Qingliang Yang Menglin Huang Qiaoli Hao FAST Collaboration Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China National Astronomical Observatories Chinese Academy of Sciences(CAS)Beijing 100101China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The FAST All Sky HI survey(FASHI)was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope(FAST),spanning approximately 22000 square degrees of declination between-14°and+66°,and in the frequency range of 1050-1450 MHz,with the expectation of eventually detecting more than 100000 HI *** August 2020 and June 2023,FASHI had covered more than 7600 square degrees,which is approximately 35%of the total sky observable by *** has a median detection sensitivity of around 0.76 m Jy beam-1and a spectral line velocity resolution of~6.4 km s-1at a frequency of~1.4 *** of now,a total of 41741 extragalactic HI sources have been detected in the frequency range 1305.5-1419.5 MHz,corresponding to a redshift limit of z■*** cross-matching FASHI sources with the Siena Galaxy Atlas(SGA)and the Sloan Digital Sky Survey(SDSS)catalogs,we found that 16972(40.7%)sources have spectroscopic redshifts and 10975(26.3%)sources have only photometric *** of the remaining 13794(33.0%)HI sources are located in the direction of the Galactic plane,making their optical counterparts difficult to identify due to high extinction or high contamination of Galactic stellar *** on current survey results,the FASHI survey is an unprecedented blind extragalactic H I *** has higher spectral and spatial resolution and broader coverage than the Arecibo Legacy Fast ALFA Survey(ALFALFA).When completed,FASHI will provide the largest extragalactic HI catalog and an objective view of HI content and large-scale structure in the local universe.

关键词： surveys redshifts galaxies telescope radio lines HI line

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New HⅠObservations Toward the NGC 5055 Galaxy Group with FAST

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Research in Astronomy and Astrophysics 2024年第7期24卷 249-256页

作者： xiao-lan liu Ming Zhu Jin-Long Xu Peng Jiang Chuan-Peng Zhang Nai-Ping Yu Jun-Jie Wang Yan-Bin Yang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China GEPI Observatoire de ParisUniversite PSLCNRSPlace Jules Janssen92195 MeudonFrance

We report a new high-sensitivity HⅠmapping observation of the NGC 5055 galaxy group over an area of 1°.5×0°.75 with the Five-hundred-meter Aperture Spherical radio Telescope(FAST).Our observation reveals that the warped HⅠdisk of NGC 5055 is more extended than what was previously observed by WSRT,out to239(61.7 kpc).The total HⅠmass of NGC 5055 is determined to be~1.1×10^(10)M_Θ.We identified three HⅠclouds with HⅠmasses of the order of~10^(7)M_Θat the southeastern edge of the HⅠdisk,as well as a candidate high-velocity cloud with an HⅠmass of(1.2±0.5)×10^(6)M_Θto the north of NGC *** HⅠcontent of UGCA337 is robustly detected for the first time by the FAST *** has a narrow HⅠlinewidth of W_(50)=17.4±3.8 km s^(-1)with a total HⅠmass of(3.5±0.3)×10^(6)M_Θ.Comparing the gas content and g-r color of UGCA 337 with typical low-mass dwarf galaxies,UGCA 337 appears relatively gas-poor despite its blue *** suggests that UGCA 337 may have undergone gas stripping in the *** also analyzed the possible origin of the diffuse HⅠclouds located at the outskirts of NGC 5055,and speculate that they might be the remnant features of a merger event in the past.

关键词： galaxies evolution-galaxies structure-galaxies individual(NGC 5055)-galaxies kinematics and dynamics-galaxies interactions

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Properties of the high-mass star forming region IRAS 22475+5939

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Research in Astronomy and Astrophysics 2012年第7期12卷 845-856页

作者： xiao-lan liu Jun-Jie Wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

IRAS 22475＋5939 has been we can still discover new characteristics well studied by previous astronomers, but about it, using the first observations of the lines from CO J=2-1, 13C0 J=2-1 and 13CO J=3-2 by the KOSMA 3m telescope. The mapping of the intensity ratio of 13CO J=3-2 and 13CO J=2-1 shows that the distribution of the temperature has two peaks, neither of which coincide with the IRAS 22475＋5939 source or the center of the HII region, but rather are located at the edge of the HII region. Overlays of the Spitzer IRAC 8 p.m with CO contours indicate that they are associated with each other and that the strongest polycyclic aro- matic hydrocarbon （PAH） emission is at the IRAS 22475＋5939 source position. The IRAS LRS spectrum at 7μm-23 μm and the PHT-s spectrum at 2μm-12μm of the IRAS 22475＋5939 source also exhibit strong PAH emission characteristics in the main PAH bands： The diversity of the PAH family should be responsible for the plateaus in the PAH emission in the PHT-s and IRAS-LRS spectra. Analysis and mod- eling in the infrared bands suggest that IRAS 22475＋5939 is more likely to be a class I young stellar object. Where this is the case, the star is likely to have a tempera- ture of Tefr-9995.8K, mass-15.34Mo, luminosity -1.54×104 L- and age 1.54-104 yr. The model shows that circumstellar disc emission is important for wavelengths between 1 and 10μm, otherwise, the envelope fluctuates for A 〉 10μm. Bipolar outflow is confirmed in the molecular cloud, and the excited star of the HII region could be the driving source of the outflow. High resolution is required fm better results.

关键词： ISM: jets and outflow -- ISM: molecular -- ISM: kinematical and dy-namics -- star formation

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Convex Relaxation Algorithm for a Structured Simultaneous Low-Rank and Sparse Recovery Problem

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Journal of the Operations Research Society of China 2015年第3期3卷 363-379页

作者： Le Han xiao-lan liu Department of Mathematics South China University of TechnologyGuangzhou 510641China

This paper is concerned with the structured simultaneous low-rank and sparse recovery,which can be formulated as the rank and zero-norm regularized least squares problem with a hard constraint diag(■)=*** this class of NP-hard problems,we propose a convex relaxation algorithm by applying the accelerated proximal gradient method to a convex relaxation model,which is yielded by the smoothed nuclear norm and the weighted l1-norm regularized least squares problem.A theoretical guarantee is provided by establishing the error bounds of the iterates to the true solution under mild restricted strong convexity *** the best of our knowledge,this work is the first one to characterize the error bound of the iterates of the algorithm to the true ***,numerical results are reported for some random test problems and synthetic data in subspace clustering to verify the efficiency of the proposed convex relaxation algorithm.

关键词： Simultaneous low-rank and sparse recovery Convex relaxation Error bound

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Optical monitoring and IDV analysis of the blazars S50716+714 and 3C 273

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Research in Astronomy and Astrophysics 2021年第4期21卷 297-310页

作者： xiao-lan liu Yu-Hai Yuan Hong-Ren Huang Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

S50716+714 and 3C 273 are frequently studied blazars,which show obvious optical variabilities with different *** the 1.0 m telescope at the Yunnan Observatory,we monitored the two *** S50716+714,we report 990 observations during the monitoring duration from JD 2458536 to JD *** 3C 273,there are 884 observations during the monitoring duration from JD 2458539 to *** on those observations,we obtain the following results.(1)For S50716+714,there lie intraday optical variabilities(IDVs),with timescales from 0.31 hours to 2.64 *** 3C 273,it is possible that there lie IDVs,with timescales from 0.36 hours to 0.49 hours.(2)The time delay of S50716+714 isτRI=3.46 min between R and I bands,and the time delay of 3C273 isτIV=6.42 min between I and V bands.(3)We find that,for S50716+714,there lies a suspected intra-day period,P≈185.78 min;for 3C273,there lie intra-day periods,which are about~60 min and~80 min.

关键词： quasars:general quasars:individual(S50716+714 3C 273) galaxies:photometry

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A statistical study towards high-mass BGPS clumps with the MALT90 survey

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Research in Astronomy and Astrophysics 2018年第1期18卷 31-58页

作者： xiao-lan liu Jin-Long Xu Chang-Chun Ning Chuan-Peng Zhang xiao-Tao liu National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China NAOC-TU Joint Center for Astrophysics Lhasa 850000 China Tibet University Lhasa 850000 China Department of Finance Central China Normal University Wuhan 430079 China

In this work,we perform a statistical investigation towards 50 high-mass clumps using data from the Bolocam Galactic Plane Survey（BGPS）and Millimetre Astronomy Legacy Team 90-GHz survey（MALT90）.Eleven dense molecular lines（N2H^＋（1–0）,HNC（1–0）,HCO^＋（1–0）,HCN（1–0）,HN^（13）C（1–0）,H^（13）CO^＋（1–0）,C2H（1–0）,HC3N（10–9）,SiO（2–1）,^（13）CS（2–1）and HNCO（4（4,0）-3（0,3）））are detected.N2H^＋ and HNC are shown to be good tracers for clumps in various evolutionary stages since they are detected in all the *** detection rates of N-bearing molecules decrease as the clumps evolve,but those of O-bearing species increase with ***,the abundance ratios[N2H^＋]/[HCO^＋]and log（[HC3N]/[HCO^＋]）decline with log（[HCO^＋]）as two linear functions,*** suggests that N^＋2H^＋ and HC3N transform to HCOas the clumps *** also find that C2H is the most abundant molecule with an order of magnitude 10^（-8）.In addition,three new infall candidates,G010.214–00.324,G011.121–00.128 and G012.215–00.118（a）,are discovered to have large-scale infall motions and infall rates with an order of magnitude 10^（-3）M⊙yr^（-1）.

关键词： stars:formation ISM:abundance ISM:molecules radio lines:ISM ISM:kinematics and dynamics

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Gas emission and dynamics in the infrared dark cloud G31.23＋0.05

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Research in Astronomy and Astrophysics 2017年第4期17卷 35-48页

作者： xiao-lan liu Jun-Jie Wang Jin-Long Xu Chuan-Peng Zhang National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China NAOC-TU Joint Center for Astrophysics Lhasa 850000China

We performed a multiwavelength study towards the infrared dark cloud （IRDC） G31.23＋0.05 with new CO observations from Purple Mountain Observatory and archival data （the GLIMPSE, MIPSGAL, HERSCHEL, ATLASGAL, BGPS and NVSS surveys）. From these observations, we iden- tified three IRDCs with systemic velocities of 108.36 ± 0.06 （cloud A）, 104.22 ± 0.11 （cloud B） and 75.73 ± 0.07 km s-1 （cloud C） in the line of sight towards IRDC G31.23. Analyses of the molecular and dust emission suggest that cloud A is a filamentary structure containing a young stellar object; clouds B and C both include a starless core. Clouds A and B are gravitationally bound and have a chance to form stars. In addition, the velocity information and the position-velocity diagram suggest that clouds A and B are adjacent in space and provide a clue hinting at a possible cloud-cloud collision. Additionally, the distribution of dust temperature shows a temperature bubble. The compact core in cloud A is associated with an UCHII region, an IRAS source, H20 masers, CH3OH masers and OH masers, suggesting that massive star formation is active there. We estimate the age of the HII region to be （0.03-0.09）Myr, indicating that the star inside is young.

关键词： stars formation - ISM HII regions - ISM molecules - ISM individual (IRDCG31.23+0.05) - ISM kinematics and dynamics

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Resonance Light Scattering Method for Determination of Amikacin with Potassium Ferrioxalate as a Probe

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Chemical Research in Chinese Universities 2010年第3期26卷 366-370页

作者： HU xiao-li AN lan-xiang liu Shao-pu liu Zhong-fang LI Cui-xia Key Laboratory of Luminescence and Real-Time Analysis Ministry of Education School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 P. R. China

In a weak acid medium, potassium ferrioxalate（PF） can react with some aminoglycoside（AGs） antibiotics, such as amikacin（AMK）, kanamycin（KANA）, tobramycin（TOB） and gentamicin（GEN）, to form ion-association complexes. It results in the enhancement of resonance light scattering（RLS） in different degrees. The maximum scattering peaks are all located at 345 nm. Among them, the relative scattering intensity（AIRLs） of AMK system is much higher than that of KANA, TOB or GEN. Therefore the method is more propitious to the determination of trace amounts of AMK. The optimum reaction conditions, influencing factors, and the relationship between scattering intensity and concentration of antibiotics were investigated by means of the proposed method. The enhancement of RLS signals is directly proportional to the concentration of antibiotics in a certain range of concentration. A new resonance light scattering method for the determination of AMK and other aminoglycoside antibiotics with [Fe（C2O4）3]^3- as a probe is thus established based on it. The method exhibits high sensitivity and good selectivity. The detection limit（3σ） for AMK is 1.8 ng/mL. The method can be applied to the determination of AMK in clinical serum samples. The reaction mechanism and the reasons for RLS enhancement are discussed in this paper.

关键词： Resonance light scattering Amikacin Aminoglycoside antibiotics Potassium ferrioxalate

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Recent advances in catalytic enantioselective direct C–H bond functionalization of electrondeficient N-containing heteroarenes

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Organic Chemistry Frontiers 2022年第1期9卷 265-280页

作者： xiao-lan liu Luo-Bin Jiang Mu-Peng Luo Zhi Ren Shou-Guo Wang Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences1068 Xueyuan AvenueShenzhenChina College of Pharmacy Shenzhen Technology University3002 Lantian RoadShenzhenChina School of Medical Imaging Xuzhou Medical UniversityXuzhouChina

Catalytic enantioselective direct C–H bond functionalization of electron-deficient N-containing heteroarenes represents one of the most straightforward and powerful protocols to construct diverse enantioenriched highly functionalized N-heteroarene *** catalytic systems and a variety of strategies for highly chemo-and stereoselective C–H functionalization of electron-deficient N-containing heteroarenes have been developed over the past few *** review summarized the rapid progress in the catalytic asymmetric C–H functionalization of N-containing heteroarenes and discussed the challenges and potential of the field in the current stage.

关键词： deficient catalytic enantioselective

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Synthesis and Structure of Zinc Complex of N, N-bis ( benzimidazol-2-yl-methyl ) amine

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Chinese Chemical Letters 2001年第6期12卷 563-564页

作者： xiao lan liu Qing Yan CHENG Xia YANG Zhi Wei MIAO Wei liu Fang Ming MIAO College of Chemistry and Life Science Tianjin Normal UniversityTianjin 300074

The Zinc complex of N, N-bis (benzimidazol 2-yl-methy])amine has been synthesized and its crystal structure determined by X-ray diffraction method. The structure features of the complex are described.

关键词： Zinc compex N N-bis (benzimidazol-2-yl-methyl)amine superoxide dismutase (SOD)

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