| 1 | Repeating fast radio bursts from collapses of the crust of a strange star显示文摘Strange stars(SSs)are compact objects made of deconfined quarks.It is hard to distinguish SSs from neutron stars as a thin crust composed of normal hadronic matter may exist and obscure the whole surface of the SS.Here we suggest that the intriguing repeating fast radio bursts(FRBs)are produced by the intermittent fractional collapses of the crust of an SS induced by refilling of materials accreted from its low-mass companion.The periodic/sporadic/clustered temporal behaviors of FRBs could be well understood in our scenario.Especially,the periodicity is attributed to the modulation of accretion rate through the disk instabilities.To account for a~16-day periodicity of the repeating FRB source of 180916.J0158+65,a Shakura-Sunyaev disk with a viscosity parameter of 0.004 and an accretion rate of 3×10^(16)gs^(-1) is invoked.Our scenario,if favored by future observations,will serve as indirect evidence for the strange quark matter hypothesis. | Jinjun Geng Bing Li Yongfeng Huang | 2021 | The Innovation2021，2，4： | 1 |
| 2 | Science with the 2.5-meter Wide Field Survey Telescope(WFST)显示文摘The Wide Field Survey Telescope(WFST) is a dedicated photometric surveying facility being built jointly by University of Science and Technology of China(USTC) and the Purple Mountain Observatory(PMO). It is equipped with a 2.5-meter diameter primary mirror, an active optics system, and a mosaic CCD camera with 0.73 gigapixels on the primary focal plane for highquality image capture over a 6.5-square-degree field of view. The installation of WFST near the summit of Saishiteng mountain in the Lenghu region is scheduled in summer of 2023, and the operation is planned to start three months later. WFST will scan the northern sky in four optical bands(u, g, r and i) at cadences from hourly/daily in the deep high-cadence survey(DHS) program, to semi-weekly in the wide field survey(WFS) program. During a photometric night, a nominal 30 s exposure in the WFS program will reach a depth of 22.27, 23.32, 22.84, and 22.31(AB magnitudes) in these four bands, respectively, allowing for the detection of a tremendous amount of transients in the low-z universe and a systematic investigation of the variability of Galactic and extragalactic objects. In the DHS program, intranight 90 s exposures as deep as 23(u) and 24 mag(g), in combination with target of opportunity follow-ups, will provide a unique opportunity to explore energetic transients in demand for high sensitivities, including the electromagnetic counterparts of gravitational wave events, supernovae within a few hours of their explosions,tidal disruption events and fast, luminous optical transients even beyond redshift of unity. In addition, the final 6-year co-added images, anticipated to reach g■25.8 mag in WFS or 1.5 mags deeper in DHS, will be of fundamental importance to general Galactic and extragalactic science. The highly uniform legacy surveys of WFST will serve as an indispensable complement to those of the Vera C. Rubin Observatory's Legacy Survey of Space and Time(LSST) that monitors the southern sky. | Tinggui Wang Guilin Liu Zhenyi Cai Jinjun Geng Min Fang Haoning He Ji-an Jiang Ning Jiang Xu Kong Bin Li Ye Li Wentao Luo Zhizheng Pan Xuefeng Wu Ji Yang Jiming Yu Xianzhong Zheng Qingfeng Zhu Yi-Fu Cai Yuanyuan Chen Zhiwei Chen Zigao Dai Lulu Fan Yizhong Fan Wenjuan Fang Zhicheng He Lei Hu Maokai Hu Zhiping Jin Zhibo Jiang Guoliang Li Fan Li Xuzhi Li Runduo Liang Zheyu Lin Qingzhong Liu Wenhao Liu Zhengyan Liu Wei Liu Yao Liu Zheng Lou Han Qu Zhenfeng Sheng Jianchun Shi Yiping Shu Zhenbo Su Tianrui Sun Hongchi Wang Huiyuan Wang Jian Wang Junxian Wang Daming Wei Junjie Wei Yongquan Xue Jingzhi Yan Chao Yang Ye Yuan Yefei Yuan Hongxin Zhang Miaomiao Zhang Haibin Zhao Wen Zhao | 2023 | Science China(Physics,Mechanics & Astronomy)2023，66，10： | 1 |
| 3 | Phase Transformation and Magnetic Properties of Mechanically Alloyed PrCo5-based Magnets显示文摘基于 PrCo_5 的 nanograin Pr_xCo_(100x )(x=14~22 ) 有高 coercivitywere 的合金由机械 alloying 并且随后的退火综合了。结晶化,阶段部件和合金的磁性系统地被调查。为 x=14 的合金的主要阶段与菱形的 Th_2Zn_(17 ) 类型是 Pr_2Co_(17 ) 。Pr_2Co_(17 ) 的数量与增加 Pr 内容分阶段执行减少,并且有 hexagonalCaCu_5 类型的将近单个的阶段 PrCo_5 在 Pr_(19 )Co_(81 ) 合金被形成。 Pr 内容的另外的增加与它大约 350 deg C.Remanences 减少单调地与增加 Pr 满足的居里温度导致另一个有磁力地难的 Pr_2Co_7 阶段的形成,而 coercivities 增加,为更高的 Pr 内容为 2 min ,然后减少为 5 h 和退火的 at973 K 在Pri_( 19 )Co_( 81 )粉末 milled 到达 2040 kA/m ( 25.6 kOe )的最大值。高 coercivity 被归因于 PrCo_5 阶段和它的 nanoscale 谷物尺寸的高 anisotropy 地。 | Xinguo ZHAO Zhidong ZHANG Qi YAO Jinjun LIU Weijun REN Wei LIU Dianyu GENG | 2006 | Journal of Materials Science & Technology2006，22，6： | 1 |
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