中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
首页 机构 成果 学者
  
  1. CAS IR Grid
机构
采集方式
内容类型
发表日期
学科主题
筛选

浏览/检索结果: 共41条，第1-10条 帮助

条数/页： 排序方式：
Carbon Kuznets curve in China: Nighttime light analysis in prefecture-level cities 期刊论文  OAI收割
HELIYON, 2024, 卷号: 10, 期号: 16, 页码: e36312
作者:  Zheng, Xiaoqi;  Wang, Jiaying;  Xu, Xiangbo;  Yu, Ran;  Zhang, Sheng
  |  收藏  |  浏览/下载：10/0  |  提交时间：2024/09/19
Leaf Carbon Exchange of Two Dominant Plant Species Impacted by Water and Nitrogen Application in a Semi-Arid Temperate Steppe 期刊论文  OAI收割
FRONTIERS IN PLANT SCIENCE, 2022, 卷号: 13
作者:  Zhang, Xiaolin;  Zhai, Penghui;  Huang, Jianhui
  |  收藏  |  浏览/下载：3/0  |  提交时间：2024/03/07
Photometric Study and Absolute Parameter Estimation of Six Totally Eclipsing Contact Binaries 期刊论文  OAI收割
Astronomical Journal, 2021, 卷号: 162, 期号: 1, 页码: 13
作者:  Li, Kai;  Xia, Qi-Qi;  Kim, Chun-Hwey;  Gao, Xing;  Hu, Shao-Ming
  |  收藏  |  浏览/下载：27/0  |  提交时间：2022/06/30
Characteristics and scenarios projection of NEE change in an alpine meadow on the Tibetan Plateau 期刊论文  OAI收割
INTERNATIONAL JOURNAL OF GLOBAL WARMING, 2021, 卷号: 24, 期号: 3-4
作者:  Du, Mingyuan;  Li, Yingnian;  Zhang, Fawei;  Zhao, Liang;  Li, Hongqin
  |  收藏  |  浏览/下载：40/0  |  提交时间：2021/11/18
The long-lived Type IIn SN 2015da: Infrared echoes and strong interaction within an extended massive shell star star star 期刊论文  OAI收割
Astronomy & Astrophysics, 2020, 卷号: 635, 页码: A39
作者:  Tartaglia, L.;  Pastorello, A.;  Sollerman, J.;  Fransson, C.;  Mattila, S.
  |  收藏  |  浏览/下载：24/0  |  提交时间：2021/06/25
The braking index of PSR B0540-69 and the associated pulsar wind nebula emission after spin-down rate transition 期刊论文  OAI收割
Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 494, 页码: 1865-1870
作者:  HXMT
  |  收藏  |  浏览/下载：54/0  |  提交时间：2022/02/08
stars: magnetic field  stars: neutron  pulsars: general  Astrophysics  - High Energy Astrophysical Phenomena  Abstract: In 2011 December, PSR B054-69 experienced a spin-down rate transition (SRT), after which the spin-down power of the pulsar increased by $\sim 36{{\ \rm per\ cent}}$. About 1000 d after the SRT, the X-ray luminosity of the associated pulsar wind nebula (PWN) was found to brighten by $32\pm 8{{\ \rm per\ cent}}$. After the SRT, the braking index n of PSR B0540-69 changes from n = 2.12 to 0.03 and then keeps this value for about five years before rising to n = 0.9 in the following years. We find that most of the current models have difficulties in explaining the measured braking index. One exceptive model of the braking index evolution is the increasing dipole magnetic field of PSR B0540-69. We suggest that the field increase may result from some instabilities within the pulsar core that enhance the poloidal component at the price of toroidal component of the magnetic field. The increasing dipole magnetic field will result in the X-ray brightening of the PWN. We fit the PWN X-ray light curve by two models: one assumes a constant magnetic field within the PWN during the brightening and the other assumes an enhanced magnetic field proportional to the energy density of the PWN. It appears that the two models fit the data well, though the later model seems to fit the data a bit better. This provides marginal observational evidence that magnetic field in the PWN is generated by the termination shock. Future high-quality and high-cadence data are required to draw a solid conclusion.  
An underlying clock in the extreme flip-flop state transitions of the black hole transient Swift J1658.2-4242 期刊论文  OAI收割
Astronomy and Astrophysics, 2020, 卷号: 641, 页码: A101
作者:  HXMT
  |  收藏  |  浏览/下载：58/0  |  提交时间：2022/02/08
accretion  accretion disks  black hole physics  X-rays: binaries  time  Astrophysics - High Energy Astrophysical Phenomena  Abstract:
Aims: Flip-flops are top-hat-like X-ray flux variations, which have been observed in some transient accreting black hole binary systems, and feature simultaneous changes in the spectral hardness and the power density spectrum (PDS). They occur at a crucial time in the evolution of these systems, when the accretion disc emission starts to dominate over coronal emission. Flip-flops remain a poorly understood phenomenon, so we aim to thoroughly investigate them in a system featuring several such transitions.
Methods: Within the multitude of observations of Swift J1658.2-4242 during its outburst in early 2018, we detected 15 flip-flops, enabling a detailed analysis of their individual properties and the differences between them. We present observations by XMM-Newton, NuSTAR, Astrosat, Swift, Insight-HXMT, INTEGRAL, and ATCA. We analysed their light curves, searched for periodicities, computed their PDSs, and fitted their X-ray spectra, to investigate the source behaviour during flip-flop transitions and how the interval featuring flip-flops differs from the rest of the outburst.
Results: The flip-flops of Swift J1658.2-4242 are of an extreme variety, exhibiting flux differences of up to 77% within 100 s, which is much larger than what has been seen previously. We observed radical changes in the PDS simultaneous with the sharp flux variations, featuring transitions between the quasi-periodic oscillation types C and A, which have never been observed before. Changes in the PDS are delayed, but more rapid than changes in the light curve. Flip-flops occur in two intervals within the outburst, separated by about two weeks in which these phenomena were not seen. Transitions between the two flip-flop states occurred at random integer multiples of a fundamental period of 2.761 ks in the first interval and 2.61 ks in the second. Spectral analysis reveals the high and low flux flip-flop states to be very similar, but distinct from intervals lacking flip-flops. A change of the inner temperature of the accretion disc is responsible for most of the flux difference in the flip-flops. We also highlight the importance of correcting for the influence of the dust scattering halo on the X-ray spectra.  
First photometric study of a short-period detached eclipsing binary NSVS 10441882 期刊论文  OAI收割
NEW ASTRONOMY, 2019, 卷号: 70, 页码: 1-6
作者:  Bin, Zhang;  Qian SB(钱声帮);  Liu NP(刘念平);  Qi-Jun, Zhi;  Zhu LY(朱俐颖)
  |  收藏  |  浏览/下载：114/0  |  提交时间：2019/05/21
Derivation of temporally continuous leaf maximum carboxylation rate (Vcmax) from the sunlit leaf gross photosynthesis productivity through combining BEPS model with light response curve at tower flux sites 期刊论文  OAI收割
Agricultural and Forest Meteorology, 2018, 卷号: 259, 期号: 0, 页码: 82-94
作者:  Xinyao Xie;  Ainong Li;  Huaan Jin;  Gaofei Yin;  Xi Nan
  |  收藏  |  浏览/下载：47/0  |  提交时间：2018/05/08
Derivation of temporally continuous leaf maximum carboxylation rate (V-cmax) from the sunlit leaf gross photosynthesis productivity through combining BEPS model with light response curve at tower flux sites 期刊论文  OAI收割
AGRICULTURAL AND FOREST METEOROLOGY, 2018, 卷号: 259, 页码: 82-94
作者:  Xinyao Xie;  Ainong Li;  Huaan Jin;  Gaofei Yin;  Xi Nan
  |  收藏  |  浏览/下载：48/0  |  提交时间：2018/07/24