A5023075452- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Cosmic Phenomena
- Polymer crystallization and properties
- Catalysis for Biomass Conversion
- Solar and Space Plasma Dynamics
- Catalysis and Hydrodesulfurization Studies
- Stellar, planetary, and galactic studies
- Spectroscopy and Quantum Chemical Studies
- Polymer Nanocomposites and Properties
- Chemical and Physical Properties in Aqueous Solutions
- biodegradable polymer synthesis and properties
- Astronomy and Astrophysical Research
- Nanomaterials for catalytic reactions
- Advanced Measurement and Detection Methods
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- Advanced Algorithms and Applications
- Free Radicals and Antioxidants
- Injection Molding Process and Properties
- Advanced NMR Techniques and Applications
- Nonlinear Optical Materials Research
- Electrocatalysts for Energy Conversion
- Intellectual Capital and Performance Analysis
National Astronomical Observatories
2018-2023
Chinese Academy of Sciences
2015-2023
Peking University
2023
Institute of Physics
2023
Central South University
2023
Songshan Lake Materials Laboratory
2023
University of Chinese Academy of Sciences
2018-2020
Polar Research Institute of China
2018
China University of Petroleum, Beijing
2017
State Key Laboratory of Chemical Engineering
2006-2010
A new, complete sample of 14,584 broad-line AGNs at $z<0.35$ is presented, which are uncovered homogeneously from the database galaxies and quasars observed spectroscopically in Sloan Digital Sky Survey Seventh Data Release. The stellar continuum properly removed for each spectrum with significant host absorption line features, careful analyses emission-line spectra, particularly H$\rm \alpha$ \beta$ wavebands, carried out. broad Balmer emission line, particularly, \alpha$, used to indicate...
As a novel X-ray focusing technology, lobster eye micro-pore optics (MPO) feature both wide observing field of view and true imaging capability, promising sky monitoring with significantly improved sensitivity spatial resolution in soft X-rays. Since first proposed by Angel (1979), the have been extensively studied, developed trialed over past decades. In this Letter, we report on first-light results from flight experiment Lobster Eye Imager for Astronomy ($LEIA$), pathfinder wide-field...
Abstract The Lobster Eye Imager for Astronomy (LEIA) detected a new X-ray transient on 2022 November 7, identified as superflare event occurring nearby K-type giant star HD 251108. flux increase was also in follow-up observations at X-ray, UV, and optical wavelengths. flare lasted about 40 days soft observations, reaching peak luminosity of ∼1.1 × 10 34 erg s −1 0.5–4.0 keV, which is roughly 60 times the quiescent luminosity. Optical brightening observed only one night. light curve well...
Abstract This work provided the first example of selective hydrodeoxygenation 5‐hydroxymethylfurfural (HMF) to 2,5‐dimethylfuran (DMF) over heterogeneous Fe catalysts. A catalyst prepared by pyrolysis an Fe‐phenanthroline complex on activated carbon at 800 °C was demonstrated be most active catalyst. Under optimal reaction conditions, complete conversion HMF achieved with 86.2 % selectivity DMF. The pathway investigated thoroughly, and hydrogenation C=O bond in rate‐determining step during...
The Lobster Eye Imager for Astronomy (LEIA), a pathfinder of the Wide-field X-ray Telescope Einstein Probe (EP) mission, was successfully launched onboard SATech-01 satellite Chinese Academy Sciences on 27 July 2022. In this paper, we introduce design and on-ground test results LEIA instrument. Using state-of-the-art Micro-Pore Optics (MPO), wide field-of-view (FoV) 346 square degrees (18.6 * 18.6 degrees) imager is realized. An optical assembly composed 36 MPO chips used to focus incident...
Abstract We report the discovery of a tidal disruption event (TDE) candidate occurring in active galactic nucleus (AGN) SDSS J022700.77-042020.6. A sudden increase flux from J0227-0420 during second half 2009 appears long-term optical, UV, and near-IR (NIR) light curves. plateau phase, following an initial decline, is seen near-UV (NUV) optical find possible evidence that NUV band may lag behind ones by ∼70–80 days with also much shorter duration, is, ∼7–15 against ∼40–50 days. The...
Abstract As Fe is more abundant and economic than Cu Ni, it probably a attractive non‐noble alternative to precious metals in biomass conversions, for which usually require promising catalysts large‐scale production. In this work, environmental benign heterogeneous iron prepared by simultaneous pyrolysis of graphitic carbon nitride precursors on activated carbon, were demonstrated be active the hydrodeoxygenation biomass‐derived 5‐hydroxymethylfurfural 2,5‐dimethylfuran. The effect...
We report on the identification of a new {\gamma}-ray-emitting narrow-line Seyfert 1 (NLS1) galaxy, SDSS J211852.96-073227.5 (hereinafter J2118-0732). The at redshift 0.26, is associated with radio source flat/inverted spectrum high frequencies. analysis its optical obtained in Sloan Digital Sky Survey (SDSS) revealed small linewidth broad component H{\beta} line (full width half-maximum = 1585 km s^{-1}), making it radio-loud NLS1 galaxy -- an intriguing class active galactic nuclei...
Abstract Nitrogen‐modified carbon nanotube‐supported ruthenium catalyst was demonstrated to be effective in the conversion of crude cyperus esculentus oil into linear liquid alkanes. The model compound stearic acid nearly quantitatively converted alkanes, and yields n‐heptadecane n‐octadecane were 89.5 % 8.5 %, respectively. mass yield alkanes from 76.6 which very close theoretical yield. could reused at least six times without loss catalytic activity during oil. We found that nitrogen...
ABSTRACT RX J0134.2-4258 is one of the most super-Eddington narrow-line Seyfert 1 (NLS1) galaxies, on which we conducted a monitoring campaign from radio to X-rays. In this paper, present detailed analysis its optical/UV spectra and broad-band spectral energy distribution. Our study shows that preferred black hole mass MBH ∼ 2 × 107 M⊙, giving accretion rate through outer disc $\dot{m}_{\rm out} \sim 20$ (assuming zero spin), compared observed luminosity ratio Lbol/LEdd 6. This reduction in...
The broad-band spectral energy distribution (SED) of active galactic nuclei (AGNs) is investigated for a well-selected sample composed 23 Seyfert 1 galaxies observed simultaneously in the optical/ultraviolet (UV) and X-ray bands with Neil Gehrels Swift Observatory. optical to UV continuum spectra are modelled, first time, emission from an accretion disc generalized radial temperature profile, order account intrinsic which found be generally redder than model prediction standard...
Abstract The imidization of poly(styrene‐ co ‐maleic anhydride) with amines may improve some its end‐use properties. objective this study was to examine the mechanism and kinetics aniline (ANL) as an amine preparation ‐ N ‐phenyl maleimide). reaction carried out in a tetrahydrofuran solution at 25–55°C ethylbenzene 85–120°C. extent determined by conductance titration, new simple method. Two consecutive reactions were involved imidization: ring opening produce acido‐amide group closing form...
A new sample of 204 low-mass black holes (LMBHs) in active galactic nuclei (AGNs) is presented with hole masses the range (1-20) * 10^5 M_sun. The AGNs are selected from a systematic search among galaxies Seventh Data Release (DR 7) Sloan Digital Sky Survey (SDSS), and careful analyses their optical spectra precise measurement spectral parameters. Combining them our previous SDSS DR 4 makes it largest LMBH so far, totaling over 500 objects. Some statistical properties combined AGN briefly...
Abstract The imidization of poly(styrene‐ co ‐maleic anhydride) (SMA) was conducted, and the glass‐transition temperatures ( T g 's) resulting products were measured with differential scanning calorimetry. contributions from functional groups maleic anhydride, N ‐phenylmaleamic acid, ‐phenylmaleimide to examined. increased in order SMA < styrene– ‐phenyl maleimide copolymer maleamic acid followed Fox equation. imidized could be controlled by conversions both ring‐opening ring‐closing...
Abstract We present multiwavelength studies of a transient X-ray source, XMMSL1 J131952.3+225958, associated with the galaxy NGC 5092 at z = 0.023 detected in XMM-Newton SLew survey (XMMSL). The source brightened <?CDATA $0.2\mbox{--}2\,\mathrm{keV}$?> band by factor $\gt 20$?> 2005 as compared previous flux limits and then faded >200 observed 2013 Swift 2018. At flaring state spectrum can be modeled blackbody temperature ∼60 eV an overall luminosity $\sim \,1.5\times {10}^{43}$?> erg s...
Low surface brightness galaxies (LSBGs) are defined as that fainter than dark night sky and important for studying our universe. Particularly, edge-on useful the study of rotational velocity dynamical properties galaxies. Hence here we focus on searching LSBGs. In order to find these dim galaxies, a series effects caused by inclination, including profile, internal extinction, scale length, have been corrected. this work, present catalog 281 LSBG candidates, which selected from crossmatch...
We report the discovery of large amplitude X-ray variability in low luminosity AGN (LLAGN) MGC 7589, and present possible observational evidence for accretion mode transition this source. Long-term flux variations by a factor more than 50 are found using data obtained Swift/XRT XMM-Newton over 17 years. Results long-term monitoring UV, optical infrared bands ~20 years also presented. The Eddington ratio increased from $10^{-3}$ to $\sim0.13$, suggesting flow an ADAF standard thin disc....
Abstract On the basis of competitive reactions intermediate poly(styrene‐ co ‐ N ‐phenyl maleamic acid) (SNPMA) to produce either ‐maleic anhydride) (SMA) or maleimide) (SNPMI), imidization kinetics SMA with aniline in molten state were investigated by a novel approach. The volatiles emitted during reaction SNPMA monitored online both thermogravimetric analysis and Fourier transform infrared (FTIR) integrated technology. experimental results directly definitely indicate that amidization from...
A dozen X-ray supernova shock breakout (SN SBO) candidates were reported recently based on XMM-Newton archival data, which increased the selected SN SBO sample by an order of magnitude. Assuming they are genuine SBOs, we study luminosity function (LF) improving upon method used in our previous work. The light curves and spectra to derive maximum volume within these objects could be detected with simulation. results show that LF can described either a broken power law (BPL) indices (at 68$\%$...
LEIA (Lobster Eye Imager for Astronomy) detected a new X-ray transient on November 7, 2022, identified as superflare event occurring nearby RS CVn-type binary HD 251108. The flux increase was also in follow-up observations at X-ray, UV and optical wavelengths. flare lasted about 40 days soft observations, reaching peak luminosity of ~1.1 * 10^34 erg/s 0.5-4.0 keV, which is roughly 60 times the quiescent luminosity. Optical brightening observed only one night. light curve well described by...
Abstract Although flares from late-type main-sequence stars have been frequently detected in the multiwavelength, associated dynamical process has rarely reported so far. Here, we report follow-up observations of an X-ray transient triggered by Wide-field Telescope onboard Einstein Probe at UT08:45:08 2024, May 7. The photometry multibands and time-resolved spectroscopy started 3 hr 7.5 after trigger, which enables us to identify as a flare M-dwarf 2MASS J12184187−0609123. bolometric energy...