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	On the Terrestrial Gamma Ray Flashes Preceding Narrow Bipolar Events 期刊论文 OAI收割 Geophysical Research Letters, 2021, 卷号: 48, 页码: e92160 作者: HXMT \| 收藏 \| 浏览/下载：32/0 \| 提交时间：2022/02/08 low frequency magnetic sferics narrow bipolar events (NBEs) relativistic feedback mechanism Terrestrial Gamma ray Flashes (TGFs) Abstract: Narrow bipolar events (NBEs) are occasionally reported to occur within a few ms after Terrestrial Gamma ray Flashes (TGFs), while the formation mechanism remains mysterious partially due to the lack of sufficient observations. Here, nine more TGFs of this scenario are reported with concurrent LF sferics and lightning location data. The gamma ray production in these TGFs preceded the occurrence of NBEs by a minimum of 60 µs up to 13.5 ms, and no other fast leader discharge was found within 20 ms before the TGF. The TGF preceded positive NBEs occurred at altitudes of 8.6-11 km in thunderstorms, likely in the high electric field (E field) region of lightning initiation. The analyses show that the NBE preceding TGFs bear harder energy spectrum with larger proportion of high energy photons than EIP related TGFs produced in association with lightning leader. Our findings support the relativistic feedback mechanism of gamma ray generation in the large scale thunderstorm E field.
	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：52/0 \| 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 distances^1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources^4-13, 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 flare^18-21. 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.
	Thermal-Induced Dissociation and Unfolding of Homodimeric DsbC Revealed by Temperature-Jump Time-Resolved Infrared Spectra 期刊论文 OAI收割 BIOPHYSICAL JOURNAL, 2009, 卷号: 97, 期号: 10, 页码: 2811 Li, H; Ke, HM; Ren, GP; Qiu, XG; Weng, YX; Wang, CC 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/09/23 DISULFIDE BOND FORMATION HELIX-COIL TRANSITION ESCHERICHIA-COLI SECONDARY STRUCTURES PROTEIN-STRUCTURE CRYSTAL-STRUCTURE CYTOCHROME-C FAST EVENTS SPECTROSCOPY ISOMERASE
	Nanosecond-time-resolved infrared spectroscopic study of fast relaxation kinetics of protein folding by means of laser-induced temperature-jump 期刊论文 OAI收割 CHINESE PHYSICS, 2005, 卷号: 14, 期号: 12, 页码: 2484 Zhang, QL; Wang, L; Weng, YX; Qiu, XG; Wang, WC; Yan, JX 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/09/24 FAST EVENTS DYNAMICS PEPTIDE SYSTEMS RANGE