中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共7条，第1-7条

帮助

条数/页：排序方式：
	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.
	Fabrication of highly dispersed Ru nanoparticles stabilized in coated carbon shell via one-pot co-synthesis strategy for aqueous hydrogenation of bio-based itaconic acid 期刊论文 OAI收割 CATALYSIS TODAY, 2019, 卷号: 319, 页码: 197-205 作者: Xu, Jie; Huang, Qianqian; Yu, Weiqiang; Lu, Fang; Lu, Rui \| 收藏 \| 浏览/下载：63/0 \| 提交时间：2019/06/20 High-dispersed Stabilized Ru Hydrogenation Itaconic acid
	High conversion efficiency distributed feedback laser from a dye-doped holographic transmission grating 期刊论文 OAI收割 Journal of Physics D-Applied Physics, 2018, 卷号: 51, 期号: 4, 页码: 7 作者: Liu, L. J.; Zhan, G. Y.; Kong, X. B.; Liu, Y. G.; Xuan, L. \| 收藏 \| 浏览/下载：17/0 \| 提交时间：2019/09/17 distributed feedback dye laser holographic polymer dispersed liquid crystal orientation high conversion efficiency dispersed liquid-crystal amplified spontaneous emission low-threshold Physics
	Facile synthesis of semiconductor and noble metal nanocrystals in high-boiling two-phase liquid/liquid systems 期刊论文 iSwitch采集 Journal of physical chemistry c, 2008, 卷号: 112, 期号: 7, 页码: 2266-2270 作者: Yu, Qiyu; Liu, Chunyan; Zhang, Zhiying; Liu, Yun 收藏 \| 浏览/下载：25/0 \| 提交时间：2019/05/10 Novel high-boiling liquid/liquid systems were introduced for the synthesis of semiconductor and noble metal Nanocrystals. polyols and long-chain hydrocarbons were utilized to form such two-phase systems. because Of the hiah-boiling nature These systems may be conveniently employed for nanocrystal synthesis at relatively High temperatures (under the normal pressure) and thus are useful alternatives to toluene/water. cds and ag Nanocrystals were successfully prepared in an octadecene (ode)/glycerol system via interfacial processes Demonstrating the effectiveness of this class of two-phase systems. as-prepared nanocrystals had hydrophobic Surfaces and were dispersed in the ode phase of the system. furthermore A congeneric two-phase system Of liquid paraffin/glycerol was also found to be effective for the synthesis of cds and ag nanocrystals.
	Oxidation of a novel chromium coating with CeO2 dispersions 期刊论文 OAI收割 Oxidation of Metals, 2004, 卷号: 62, 期号: 5-6, 页码: 411-426 L. Zhu; X. Peng; J. Yan; F. Wang 收藏 \| 浏览/下载：18/0 \| 提交时间：2012/04/14 electrodepostion chromizing CeO2-dispersed chromizing coating mild-carbon steel high-temperature oxidation reactive-element effect high-temperature oxidation ion-implanted yttrium reactive-element selective oxidation stainless-steels nickel segregation growth scales cr2o3
	Development and oxidation of a RexOy- modified chromizing coating 期刊论文 OAI收割 HIGH TEMPERATURE CORROSION AND PROTECTION OF MATERIALS 6, PRT 1 AND 2, PROCEEDINGS, 2004, 卷号: 461-464, 页码: 255-263 作者: Zhu, L; Peng, X; Wang, F; Wu, W \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2021/02/02 composite electrodepostion chromizing CeO2-dispersed chromizing coating high temperature oxidation reactive element effect
	Oxidation of a La2O3-modified aluminide coating 期刊论文 OAI收割 Scripta Materialia, 2001, 卷号: 44, 期号: 7, 页码: 1033-1038 X. Peng; T. Li; W. P. Pan 收藏 \| 浏览/下载：14/0 \| 提交时间：2012/04/14 electrodepostion aluminizing La2O3-dispersed aluminide coating high temperature oxidation reactive element effect reactive element behavior alloys stress nickel scale films