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Evolution of surface and subsurface properties of Zr-4 alloy under the combined effects of laser heat treatment and laser gas nitriding: Microscopic morphology, chemical composition, and mechanical behavior 期刊论文  OAI收割
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, 2025, 卷号: 339, 页码: 22
作者:  Xu, Puhong;  Qian, Yongfeng;  An, Hong;  Guo, Haolin;  Zhang ZY(张治愚)
  |  收藏  |  浏览/下载：1/0  |  提交时间：2025/05/19
Detection of Flare Multiperiodic Pulsations in Mid-ultraviolet Balmer Continuum, Lyl Hard X-Ray, and Radio Emissions Simultaneously 期刊论文  OAI收割
The Astrophysical Journal, 2021, 卷号: 921, 页码: 179
作者:  HXMT
  |  收藏  |  浏览/下载：29/0  |  提交时间：2022/02/08
Solar flares  Solar oscillations  Solar ultraviolet emission  Solar  x-ray emission  Solar radio emission  1496  1515  1533  1536  1522  Astrophysics - Solar and Stellar Astrophysics  Abstract: Quasi-periodic pulsations (QPPs), which usually appear as temporal pulsations of the total flux, are frequently detected in the light curves of solar/stellar flares. In this study, we present the investigation of nonstationary QPPs with multiple periods during the impulsive phase of a powerful flare on 2017 September 6, which were simultaneously measured by the Hard X-ray Modulation Telescope (Insight-HXMT), as well as the ground-based BLENSW. The multiple periods, detected by applying a wavelet transform and Lomb-Scargle periodogram to the detrended light curves, are found to be ~20-55 s in the Ly`and mid-ultraviolet Balmer continuum emissions during the flare impulsive phase. Similar QPPs with multiple periods are also found in the hard X-ray emission and low-frequency radio emission. Our observations suggest that the flare QPPs could be related to nonthermal electrons accelerated by the repeated energy release process, i.e., triggering of repetitive magnetic reconnection, while the multiple periods might be modulated by the sausage oscillation of hot plasma loops. For the multiperiodic pulsations, other generation mechanisms could not be completely ruled out.  
Large solubility of silicon in an incongruent nitride: The case of reactively magnetron co-sputtered W-Si-N coatings 期刊论文  OAI收割
SURFACE & COATINGS TECHNOLOGY, 2021, 卷号: 412
作者:  Bai, Xue;  Li, Ke;  Chen, Yuyun;  Feng, Qing;  Ge, Fangfang
  |  收藏  |  浏览/下载：34/0  |  提交时间：2021/12/01
Insights into friction properties and mechanism of self-lubricating MoVN-Ag films at high temperature 期刊论文  OAI收割
VACUUM, 2020, 卷号: 176
作者:  Wang, Wenzhe;  Pu, Jibin;  Cai, Zhaobing;  Zheng, Shaoxian;  Wei, Yao
  |  收藏  |  浏览/下载：86/0  |  提交时间：2020/12/16
No pulsed radio emission during a bursting phase of a Galactic magnetar 期刊论文  OAI收割
Nature, 2020, 卷号: 587, 页码: 63-65
作者:  HXMT
  |  收藏  |  浏览/下载：48/0  |  提交时间：2022/02/08
Astrophysics - High Energy Astrophysical Phenomena  Abstract: Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources4-13, but no convincing evidence has been collected so far14. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft íray bursts15. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft íray/hard-X-ray flare18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-íray repeater (SGR) bursts were detected in íray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.  
Timing analysis of Swift J1658.2-4242's outburst in 2018 with Insight-HXMT, NICER and AstroSat 期刊论文  OAI收割
Journal of High Energy Astrophysics, 2019, 卷号: 24, 页码: 30-40
作者:  HXMT
  |  收藏  |  浏览/下载：57/0  |  提交时间：2022/02/08
Accretion  accretion disks  Black hole physics  X-rays: binaries:  Swift J1658.2-4242  Astrophysics - High Energy Astrophysical Phenomena  Abstract: We present the observational results from a detailed timing analysis of the black hole candidate Swift J1658.2-4242 during its 2018 outburst with the observations of Hard X-ray Modulation Telescope (Insight-HXMT), Neutron Star Interior Composition Explorer (NICER) and AstroSat in 0.1-250 keV. The evolution of intensity, hardness and integrated fractional root mean square (rms) observed by Insight-HXMT and NICER are presented in this paper. Type-C quasi-periodic oscillations (QPOs) observed by NICER (0.8-3.5 Hz) and Insight-HXMT (1-1.6 Hz) are also reported in this work. The features of the QPOs are analyzed with an energy range of 0.5-50 keV. The relations between QPO frequency and other characteristics such as intensity, hardness and QPO rms are carefully studied. The timing and spectral properties indicate that Swift J1658.2-4242 is a black hole binary system. Besides, the rms spectra of the source calculated from the simultaneous observation of Insight-HXMT, NICER and AstroSat support the Lense-Thirring origin of the QPOs. The relation between QPO phase lag and the centroid frequency of Swift J1658.2-4242 reveals a near zero constant when < 4Hz and a soft phase lag at 6.68 Hz. This independence follows the same trend as the high inclination galactic black hole binaries such as MAXI J1659-152.  
Scaled particle theory for bulk and confined fluids: A review 期刊论文  OAI收割
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2018, 卷号: 61, 期号: 7, 页码: 70501
作者:  Chen, XS;  Dong, W
  |  收藏  |  浏览/下载：37/0  |  提交时间：2018/12/27
Phase morphology, crystallization behavior and mechanical properties of poly(L-lactide) toughened with biodegradable polyurethane: Effect of composition and hard segment ratio 期刊论文  OAI收割
CHINESE JOURNAL OF POLYMER SCIENCE, 2015, 卷号: 33, 期号: 9, 页码: 1294-1304
作者:  Xing, Qian;  Li, Rong-bo;  Dong, Xia;  Zhang, Xiu-qin;  Zhang, Liao-yun
收藏  |  浏览/下载：40/0  |  提交时间：2015/10/27
Influence of sedimentation on crystallization of charged colloidal particles 期刊论文  OAI收割
CHINESE JOURNAL OF CHEMICAL PHYSICS, 2012, 卷号: 25, 期号: 3, 页码: 318-324
作者:  Du H(杜嬛);  Xu SH(徐升华);  Sun ZW(孙祉伟);  Liu L(刘蕾);  Sun, ZW
收藏  |  浏览/下载：83/0  |  提交时间：2013/01/18
Composition-Dependent Structural and Electronic Properties of alpha-(Si(1-x)C(x))(3)N(4) 期刊论文  OAI收割
Journal of Physical Chemistry C, 2011, 卷号: 115, 期号: 5, 页码: 2448-2453
M. Xu; S. Xu; M. Y. Duan; M. Delanty; N. Jiang; H. S. Li; L. C. Kwek; K. Ostrikov
收藏  |  浏览/下载：26/0  |  提交时间：2012/04/13