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Eremophilane-type sesquiterpenes from Ligularia hodgsonii: isolation , structural characterization, and pro-angiogenic potential 期刊论文  OAI收割
PHYTOCHEMISTRY, 2026, 卷号: 246, 页码: 12
作者:  
Wan, Zhenhua;  Peng, Huilin;  Tang, Chunping;  Qin, Jiangjiang;  Hu, Bintao
  |  收藏  |  浏览/下载:5/0  |  提交时间:2026/04/01
Application of the rapid leaf A-Ci response (RACiR) technique: examples from evergreen broadleaved species 期刊论文  OAI收割
PHOTOSYNTHESIS RESEARCH, 2023, 卷号: 155, 期号: 2, 页码: 139-146
作者:  
Lin, Quanhong;  Tian, Di;  Zhao, Changti
  |  收藏  |  浏览/下载:81/0  |  提交时间:2024/03/07
Tabernaesine J, a Novel Vincamine-Type Indole Alkaloid with 6/5/6/6/6/5/5 Heptacyclic-Ring System Scaffold from Tabernaemontana pachysiphon 期刊论文  OAI收割
CHINESE JOURNAL OF CHEMISTRY, 2022, 卷号: 40, 期号: 4, 页码: 475-479
作者:  
Yi,Wen-Fang;  Adelakun,Tiwalade A.;  Bai,Xue;  Zhang,Yu;  Hao,Xiao-Jiang
  |  收藏  |  浏览/下载:80/0  |  提交时间:2022/04/02
Gevrey genericity of Arnold diffusion in a priori unstable Hamiltonian systems 期刊论文  OAI收割
Nonlinearity, 2021, 卷号: 34, 期号: 1
作者:  
Chen,Qinbo;  Cheng,Chong-Qing
  |  收藏  |  浏览/下载:38/0  |  提交时间:2021/04/26
High-content screening of diterpenoids from Isodon species as autophagy modulators and the functional study of their antiviral activities 期刊论文  OAI收割
CELL BIOLOGY AND TOXICOLOGY, 2021, 卷号: 37, 期号: 5, 页码: 695-713
作者:  
Huang,Lihong;  Fu,Qiang;  Dai,Jia-Meng;  Yan,Bing-Chao;  Wang,Dawei
  |  收藏  |  浏览/下载:141/0  |  提交时间:2022/04/02
Synchronous X-ray/Optical QPOs from the Black Hole LMXB MAXI J1820+070 期刊论文  OAI收割
Monthly Notices of the Royal Astronomical Society, 2021
作者:  
HXMT
  |  收藏  |  浏览/下载:103/0  |  提交时间:2022/02/08
black hole physics  Low Mass X-ray Binaries  accretion  accretion  discs  stars: individual (MAXI J1820+070)  Astrophysics - High Energy  Astrophysical Phenomena  Abstract: We present high-speed optical photometry from SAAO and SALT on the black hole LMXB MAXI J1820+070 (ASSASN-18ey), some of it simultaneous with NICER, Swift and Insight-HXMT X-ray coverage. We detect optical Quasi-Periodic Oscillations (QPOs) that move to higher frequencies as the outburst progresses, tracking both the frequency and evolution of similar X-ray QPOs previously reported. Correlated X-ray/optical data reveal a complex pattern of lags, including an anti-correlation and a sub-second lag that evolve over the first few weeks of outburst. They also show correlated components separated by a lag equal to the QPO period roughly centered on zero lag, implying that the inter-band variability is strongly and consistently affected by these QPOs at a constant phase lag of roughly ±Ю The synchronisation of X-ray and optical QPOs indicates that they must be produced in regions physically very close to each other  we thus propose that they can be explained by a precessing jet model, based on analogies with V404 Cyg and MAXI J1348-630.  
Periodicity Search on X-Ray Bursts of SGR J1935+2154 Using 8.5 yr of Fermi/GBM Data 期刊论文  OAI收割
The Astrophysical Journal, 2021, 卷号: 923, 页码: L30
作者:  
HXMT
  |  收藏  |  浏览/下载:52/0  |  提交时间:2022/02/08
Ten picrotoxane-type sesquiterpenoids from the stems of Dendrobium wardianum Warner 期刊论文  OAI收割
PHYTOCHEMISTRY, 2021, 卷号: 190, 页码: 112858
作者:  
Fan,Wei-Wei;  Yang,Dan;  Cheng,Zhong-Quan;  Xu,Feng-Qing;  Dong,Fa-Wu
  |  收藏  |  浏览/下载:53/0  |  提交时间:2022/04/02
Insight-HXMT observations of Swift J0243.6+6124: the evolution of RMS pulse fractions at super-Eddington luminosity 期刊论文  OAI收割
Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 497, 页码: 5498-5506
作者:  
HXMT
  |  收藏  |  浏览/下载:78/0  |  提交时间:2022/02/08
stars: neutron  pulsars: individual: Swift J0243.6+6124  X-rays:  binaries  Astrophysics - High Energy Astrophysical Phenomena  Abstract: Based on Insight-HXMT data, we report on the pulse fraction evolution during the 2017-2018 outburst of the newly discovered first Galactic ultraluminous X-ray (ULX) source Swift J0243.6+6124. The pulse fractions of 19 observation pairs selected in the rising and fading phases with similar luminosity are investigated. The results show a general trend of the pulse fraction increasing with luminosity and energy at supercritical luminosity. However, the relative strength of the pulsation between each pair evolves strongly with luminosity. The pulse fraction in the rising phase is larger at luminosity below 7.71 × 1038 erg s-1, but smaller at above. A transition luminosity is found to be energy independent. Such a phenomenon is first confirmed by Insight-HXMT observations and we speculate that it may have relation with the radiation-pressure-dominated accretion disc.  
Constraining the X-Ray-Infrared Spectral Index of Second-timescale Flares from SGR 1935+2154 with Palomar Gattini-IR 期刊论文  OAI收割
The Astrophysical Journal, 2020, 卷号: 901, 页码: L7
作者:  
HXMT
  |  收藏  |  浏览/下载:46/0  |  提交时间:2022/02/08
Radio transient sources  Magnetars  Soft gamma-ray repeaters  2008  992  1471  Astrophysics - High Energy Astrophysical Phenomena  Astrophysics - Instrumentation and Methods for Astrophysics  Abstract: The Galactic magnetar SGR 1935+2154 has been reported to produce the first example of a bright millisecond-duration radio burst (FRB 200428) similar to the cosmological population of fast radio bursts (FRBs). The detection of a coincident bright X-ray burst represents the first observed multiwavelength counterpart of an FRB. However, the search for similar emission at optical wavelengths has been hampered by the high inferred extinction on the line of sight. Here, we present results from the first search for second-timescale emission from the source at near-infrared (NIR) wavelengths using the Palomar Gattini-IR observing system in the J band, enabled by a novel detector readout mode that allows short exposure times of ?0.84 s with 99.9% observing efficiency. With a total observing time of ?12 hr (?47,728 images) during its 2020 outburst, we place median 3Ҡlimits on the second-timescale NIR fluence of ?18 Jy ms (13.1 AB mag). The corresponding extinction-corrected limit is ?125 Jy ms for an estimated extinction of AJ = 2.0 mag. Our observations were sensitive enough to easily detect an NIR counterpart of FRB 200428 if the NIR emission falls on the same power law as observed across its radio to X-ray spectrum. We report nondetection limits from epochs of four simultaneous X-ray bursts detected by the Insight-HXMT and NuSTAR telescopes during our observations. These limits provide the most stringent constraints to date on fluence of flares at 1014 Hz, and constrain the fluence ratio of the NIR emission to coincident X-ray bursts to RNIR ? 0.025 (fluence index ?0.35).