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Low-mass and high-mass supermassive black holes in radio-loud AGNs are spun-up in different evolution paths

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Research in Astronomy and Astrophysics 2019年第10期19卷 59-64页

作者： Jing Wang Min-Zhi Kong Shun-Fang Liu da-wei xu Qiang Zhang Jian-Yan wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology Guangxi University Nanning 530004 China Key Laboratory of Space Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing 100049 China Department of Physics Hebei Normal University Shijiazhuang 050024 China

How supermassive black holes(SMBHs) are spun-up is a key issue in modern astrophysics. As an extension to the study in Wang et al., here we address the issue by comparing the host galaxy properties of nearby(z 10^7.9 M⊙)have a preference for being spun-up in classical bulges, and low-mass SMBHs(i.e., MBH = 10^6-10^7 M⊙)in pseudo-bulges. This dichotomy suggests and confirms that high-mass and low-mass SMBHs are spun-up in different ways, i.e., a major "dry" merger and a secular evolution respectively.

关键词： galaxies bulges-galaxies nuclei-galaxies Seyfert

Prone position combined with high-flow nasal oxygen could benefit spontaneously breathing, severe COVID-19 patients:A case report

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World Journal of Clinical Cases 2021年第17期9卷 4381-4387页

作者： da-wei xu Guang-Liang Li Jiong-Han Zhang Fei He Emergency Medicine The Affiliated Suqian Hospital of Xuzhou Medical UniversitySuqian 223800Jiangsu ProvinceChina Intensive Care Unit The Infectious Disease Control CenterSuqian 223800Jiangsu ProvinceChina Emergency Medicine Nanjing Drum Tower HospitalNanjing University Medical SchoolNanjing 210008Jiangsu ProvinceChina

BACKGROUND Since the outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China in December 2019,the overall fatality rate of severe and critical patients with COVID-19 is high and the effective therapy is *** SUMMARY In this case report,we describe a case of the successful combination of the prone position(PP)and high-flow nasal oxygen(HFNO)therapy in a spontaneously breathing,severe COVID-19 patient who presented with fever,fatigue and hypoxemia and was diagnosed by positive throat swab COVID-19 RNA *** therapy significantly improved the patient's clinical symptoms,oxygenation status,and radiological characteristics of lung injury during hospitalization,and the patient showed good tolerance and avoided ***,we did not find that medical staff wearing optimal airborne personal protective equipment(PPE)were infected by the new coronavirus in our *** We conclude that the combination of PP and HFNO could benefit spontaneously breathing,severe COVID-19 *** therapy does not increase risk of healthcare workers wearing optimal airborne PPE to become infected with virus particles.

关键词： COVID-19 Hypoxemia High-flow nasal oxygen Intubation and prone position Case report

Multiple scenario simulation and optimization of an urban green infrastructure network based on complex network theory:a case study in Harbin City,China

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Ecological Processes 2022年第1期11卷 439-454页

作者： Shuang Song Shao‑Han Wang Meng‑Xi Shi Shan‑Shan Hu da‑wei xu College of Landscape Architecture Northeast Forestry UniversityHarbin 150000China Key Lab for Garden Plant Germplasm Development&Landscape Eco‑Restoration in Cold Regions of Heilongjiang Province Harbin 150000China

Background:Urban green infrastructure(GI)networks play a significant role in ensuring regional ecological security;however,they are highly vulnerable to the influence of urban development,and the optimization of GI networks with better connectivity and resilience under different development scenarios has become a practical problem that urgently needs to be *** Harbin,a megacity in Northeast China,as the case study,we set five simulation scenarios by adjusting the economic growth rate and extracted the GI network in multiple scenarios by integrating the minimal cumulative resistance model and the gravity *** low‑degree‑first(LDF)strategy of complex network theory was introduced to optimize the GI network,and the optimization effect was verified by robustness ***:The results showed that in the 5%economic growth scenario,the GI network structure was more complex,and the connectivity of the network was better,while in the other scenarios,the network structure gradually degraded with economic *** optimization by the LDF strategy,the average degree of the GI network in multiple scenarios increased from 2.368,2.651,2.189,1.972,and 1.847 to 2.783,3.125,2.643,2.414,and 2.322,respectively,and the GI network structure connectivity and resilience were significantly enhanced in all ***:Economic growth did not necessarily lead to degradation of the GI network;there was still room for economic development in the study area,but it was limited under existing GI conditions,and the LDF strategy was an effective method to optimize the GI *** research results provide a new perspective for the study of GI network protection with urban economic growth and serve as a methodological reference for urban GI network optimization.

关键词： GI network Simulation Complex network theory LDF strategy Robustness

The intra-day optical monitoring of BL Lacerate object 1ES 1218+304 at its highest X-ray flux level

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Research in Astronomy and Astrophysics 2021年第8期21卷 135-140页

作者： Si-Si Sun Hua-Li Li Xing Yang Jing Lü da-wei xu Jing Wang Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100101China

We here report a monitor of the BL Lac object 1 ES 1218+304 in both B-and R-bands by the GWAC-F60 A telescope in eight nights,when it was triggered to be at its highest X-ray flux in history by the VERITAS Observatory and Swift *** ANOVA and χ^(2)-test enable us to clearly reveal an intraday variability in optical wavelengths in seven out of the eight nights.A bluer-when-brighter chromatic relationship has been clearly identified in five out of the eight nights,which can be well explained by the shock-in-jet *** addition,a quasi-periodic oscillation phenomenon in both bands could be tentatively identified in the first night.A positive delay between the two bands has been revealed in three out of the eight nights,and a negative one in the other *** identified minimum time delay enables us to estimate the MBH=2.8 × 10^(7) M_(⊙) that is invalid.

关键词： BL Lacertae objects:general BL Lacertae objects:individual(1ES1218+304) galaxies:active method:statistical

1RXS J232953.9+062814: a New SU UMa Dwarf Nova below the Period Minimum

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Chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 483-486页

作者： Jian-Yan wei, Xiao-Jun Jiang, da-wei xu, Ai-Ying Zhou and Jing-Yao Hu National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

RXS 1232953.9+062814 was identified as a cataclysmic variable by wei et al. (1999). Four low-resolution spectra of 1RXS J232953.9+062814 were obtained with the 2.16-rn telescope of the National Astronomical Observatories, of which two were at outburst, and two were at quiescence. The system is about 16.8 B and 16.5 V at quiescence, and 12.6 B and 12.6 V at outburst. The quiescent spectra were dominated by double-peaked Balmer emissions, which indicates a hydrogen-rich system with a high-inclination accretion disc. MgH and TiO absorption bands appeared in the quiescent spectrum which implies a companion with a spectral type of early M dwarf. If we take it as a MO dwarf, then the system is located at a distance of 350 pc with a proper motion velocity 150 km s-1. The superhump period of 0.046311 days was confirmed by our V photometry. The short period and the hydrogen-rich nature reveal that this system is another SU Ursae Majoris-type dwarf nova below the period minimum after V485 Centauri. 1RXS J23 2953.9+062814 is one of the most important systems for studying the evolutionary scenario of cataclysmic variables since it is much brighter than V485 Cen.

关键词： stars: dwarf novae - stars: cataclysmic variables: individual: 1RXS J232953.9 +062814

Study on Phospholipid Composition of Erythrocyte Membrane in Hypophosphatemic Cows

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Agricultural Sciences in China 2002年第3期1卷 328-332页

作者： SHI Fa-qing, xuAN da-wei, xu Shi-Wen and WANG Zhen-yong(The College of Animal Medicine , Northeast Agricultural University, Harbin 150030) The College of Animal Medicine Northeast Agricultural University Harbin 150030

The phospholipid constituents of the erythrocyte membrane of cows in hypophosophorus were detected with the field cases and the group comparison. The cows were divided into three groups: the hemoglobinuria group (HN), the hypophosphatemia group (HP) and the control group (CK). The content of the phospholipid constituent in HN and HP obviously changed: phosphatidylethaanolamine (PE) content in HN was significantly lower than that in HP and CK; but sphingomyline (SM) and phosphatidycholine (PC) + phosphatidylserine (PS) content in HN were significantly higher than that in the two other groups; in comparison between HP and CK, PC + PS content was lower and SM content was higher in HP; significant positive correlation and negative correlation were observed between serum phosphorus and PE content, serum phosphorus and SM content respectively.

关键词： Cows Phosphorus Phospholipid composition Erythrocyte membrane

基于CT的股骨有限元模型的建立及髋关节中空多孔假体植入后受力分布的初步研究(英文)

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生物化学与生物物理进展 2011年第11期38卷 1072-1078页

作者：吕大伟蔡胥王岩中国人民解放军总医院骨科北京100853

利用有限元分析的方法,对髋关节中空多孔假体植入后的受力分布改变进行研究,为改进中空多孔人工关节假体的设计提供依据.建立了股骨和假体三维有限元模型,应用有限元分析软件Ansys5.7模拟单腿负重状态,考察应力分布并进行比较.使用SPSS ... 详细信息

利用有限元分析的方法,对髋关节中空多孔假体植入后的受力分布改变进行研究,为改进中空多孔人工关节假体的设计提供依据.建立了股骨和假体三维有限元模型,应用有限元分析软件Ansys5.7模拟单腿负重状态,考察应力分布并进行比较.使用SPSS Statistics 17.0软件进行分析处理,绘制折线图.结果表明:a.开孔后张力侧最大压应力有所减小,开孔部位的应力水平变化不明显.b.与周围骨质形成连接后孔缘局部应力增加,张力侧受力改变不明显.c.短柄假体受力模式仍为远端应力集中;张力侧应力减小,开孔部位应力明显增加.d.下孔受力均大于上孔,受力方向基本一致.

关键词：有限元分析生物力学髋关节假体

The mini-GWAC optical follow-up of gravitational wave alerts – results from the O2 campaign and prospects for the upcoming O3 run

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Research in Astronomy and Astrophysics 2020年第1期20卷 107-123页

作者： damien Turpin Chao Wu xu-Hui Han Li-Ping Xin Sarah Antier Nicolas Leroy Li Cao Hong-Bo Cai Bertrand Cordier Jin-Song Deng Wen-Long Dong Qi-Chen Feng Lei Huang Lei Jia Alain Klotz Cyril Lachaud Hua-Li Li En-wei Liang Shun-Fang Liu Xiao-Meng Lu Xian-Min Meng Yu-Lei Qiu Hui-Juan Wang Jing Wang Shen Wang Xiang-Gao Wang Jian-Yan wei Bo-Bing Wu Yu-Jie Xiao da-wei xu Yang xu Yuan-Gui Yang Pin-Pin Zhang Ruo-Song Zhang Shuang-Nan Zhang Ya-Tong ZhengandSi-Cheng Zou Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China LAL Univ.Paris-SudCNRS/IN2P3Universite Paris-SaclayF-91898 OrsayFrance APC Univ Paris DiderotCNRS/IN2P3CEA/lrfuObs de ParisSorbonne Paris CiteFrance CEA Saclay DRF/IRFU/Departement d’astrophysique91191 Gif-sur-YvetteFrance School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China Universite de Toulouse IRAP 14 Av.Edouard BelinF-31000 ToulouseFrance Institut de Recherche en Astrophysique et Planetologie(IRAP) UPS-OMPToulouseFrance Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000China

The second(O2)observational campaign of gravitational waves(GWs)organized by the LIGO/Virgo Collaborations has led to several breakthroughs such as the detection of GW signals from merger systems involving black holes or neutrons *** O2,14 GW alerts were sent to the astronomical community with sky regions mostly covering over hundreds of square *** them,six were finally confirmed as real astrophysical *** 2013,a new set of ground-based robotic telescopes called Ground-based Wide Angle Camera system(GWAC)project and its pathfinder mini-GWAC has been developed to contribute to the various challenges of multi-messenger and time domain *** GWAC system is built up in the framework of the ground-segment system of the SVOM mission that will be devoted to the study of the multi-wavelength transient sky in the next *** O2,only the mini-GWAC telescope network was fully *** to the wide field of view and fast automatic follow-up capabilities of the mini-GWAC telescopes,they were adept to efficiently cover the sky localization areas of GW event *** this paper,we present the mini-GWAC pipeline we have set up to respond to GW alerts and we report our optical follow-up observations of eight GW alerts detected during the O2 *** observations provided the largest coverage of the GW localization areas with a short latency made by any optical *** found tens of optical transient candidates in our images,but none of those could be securely associated with any confirmed black hole-black hole merger *** on this first experience and the near future technical improvements of our network system,we will be more competitive in detecting the optical counterparts from some GW events that will be identified during the upcoming O3 run,especially those emerging from binary neutron star mergers.

关键词： gravitational waves methods:data analysis methods:observational (stars:)gammaray burst:general

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新型混合式高压直流输电DC/DC变换器

电力系统自动化 2018年第7期42卷 116-122页

作者：李彬彬张书鑫程达王卫徐殿国哈尔滨工业大学电气工程及自动化学院黑龙江省哈尔滨市150001

针对高压直流电网中现有DC/DC变换器拓扑在成本、效率方面的不足,提出了一种基于模块串联技术以及晶闸管、二极管串联技术的混合式DC/DC变换器拓扑,以实现高压直流电网中不同电压等级的互联。对该拓扑结构的工作原理、控制策略、元器件... 详细信息

针对高压直流电网中现有DC/DC变换器拓扑在成本、效率方面的不足,提出了一种基于模块串联技术以及晶闸管、二极管串联技术的混合式DC/DC变换器拓扑,以实现高压直流电网中不同电压等级的互联。对该拓扑结构的工作原理、控制策略、元器件参数设计、经济性等方面进行了全面的分析论证。最后,在MATLAB中进行了仿真,验证了所提DC/DC变换器的可行性。

关键词：高压直流输电直流电网 DC/DC变换器模块串联技术模块化多电平换流器