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	Concentrations, Compound Profiles, and Possible Sources of Organic UV Filters in Human Milk in China 期刊论文 OAI收割 ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2022, 页码: 1-11 作者: Liu, Yang; Gao, Lirong; Qiao, Lin; Huang, Di; Lyu, Bing \| 收藏 \| 浏览/下载：18/0 \| 提交时间：2023/02/06 ultraviolet filters human milk profiles possible sources risk assessment
	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：44/0 \| 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.
	Intra-Urban Levels, Spatial Variability, Possible Sources and Health Risks of PM2.5 Bound Phthalate Esters in Xi'an 期刊论文 OAI收割 AEROSOL AND AIR QUALITY RESEARCH, 2018, 卷号: 18, 期号: 2, 页码: 485-496 作者: Wang, Gehui; Cao, Junji; Xiao, Shun; Ho, Steven Sai Hang; Gao, Meiling \| 收藏 \| 浏览/下载：36/0 \| 提交时间：2018/09/26 Phthalate Esters Nineteen Communities Spatial Variability Possible Sources Health Risks
	Occurrence and levels of polybrominated diphenyl ethers in surface sediments from the Yellow River Estuary, China 期刊论文 OAI收割 ENVIRONMENTAL POLLUTION, 2016, 卷号: 212, 期号: 2016, 页码: 147-154 作者: Lam, Michael Hon Wah; Liu, Guijian; Liu, Houqi; Da, Chunnian; Yuan, Zijiao \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2018/10/29 Yellow River Polybrominated Diphenyl Ethers Surface Sediments Congener Profiles Possible Sources
	Polychlorinated dibenzo-p-dioxins and dibenzofurans in soils and sediments from Daliao River Basin, China 期刊论文 OAI收割 chemosphere, 2008, 卷号: 73, 期号: 10, 页码: 1640-1648 作者: Zhang, Haijun; Ni, Yuwen; Chen, Jiping; Su, Fan; Lu, Xianbo 收藏 \| 浏览/下载：27/0 \| 提交时间：2015/11/11 PCDD/F Daliao River Principal component analysis Possible sources Organochlorine chemicals Metal smelting