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Structural Properties of Early-Type Galaxies from the SDSS DR2

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 503-521页

作者： feng-shan liu Zu-Gan Deng Hong Wu Xiao-Yang Xia National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate School of Chinese Academy of Sciences Beijing 100049 China Department of Physics Tianjin Normal University Tianjin 300074 China

Two-dimensional bulge/disk light decomposition with GIM2D in both the r- and g-bands has been applied to a sample of 129 early-type galaxies brighter than 13.5 magnitude in the r-band, selected from the Sloan Digital Sky Survey Data Release 2. Intensity-weighted Fourier coefficient （α4/α） was also derived for each sample galaxy. Our analysis shows that there are correlations between bulge-to-total light ratio （B/T） with bulge Sersic index nB and between bulge and disk scale sizes. Isophotal shape parameter （α4/α） is not correlated with BIT and riB. Both bulge and disk components satisfy a color-magnitude relation. The space Fundamental Plane analysis shows that galaxies with larger B/T tend to lie tighter and closer to the line of k1 ＋ k2 = 8 （the so-called ＂zone of avoidance＂） than the galaxies with smaller B/T. It indicates that existence of the disk component may lead to scatter of the distribution on the Fundamental Plane. Our analysis also shows that k1 ＋ k2 correlates with （g-r） color and B/T, but does not correlate with （α4/α） for early-type galaxies. The fitted parameters and other retrieved parameters used in this paper for all sample galaxies are available online.

关键词： galaxies elliptical and lenticular, cD -galaxies photometry -galaxies structure - galaxies

Conditions for galaxy quenching at 0.5

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Research in Astronomy and Astrophysics 2020年第8期20卷 143-156页

作者： Xue Ge feng-shan liu Qiu-Sheng Gu Emanuele Contini Yi-Zhou Gu School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Modern Astronomy and Space Exploration Nanjing 210093China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China

We investigate two classes of conditions for galaxy quenching at 0.510^10 M⊙)have much higher stellar mass surface densities within the central 1 kpc(∑1)and smaller sizes than star-forming galaxies in the same stellar mass *** addition,the quiescent fractions significantly increase with the increase of∑1 regardless of whether galaxies are centrals or *** contrast,we find that the overall lower-mass quiescent galaxies(M*<~10^10M⊙)have slightly higher E1 and comparable sizes compared to starforming galaxies of the same mass and at the same *** z<1.5,satellites have higher halo masses and larger quiescent fractions than those of centrals at a given∑1(stellar mass).Our findings indicate that the significant growth of the galaxy cores is closely related to the quenching of massive galaxies since z^2.5,while the environmental effect plays an important role in the quenching of low-mass galaxies at z≤1.5.

关键词： galaxies:evolution galaxies:formation galaxies:high-redshift

The properties of a large volume-limited sample of face-on low surface brightness disk galaxies

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Research in Astronomy and Astrophysics 2012年第11期12卷 1486-1498页

作者： Guo-Hu Zhong Yan-Chun Liang feng-shan liu Francois Hammer Karen Disseau Li-Cai Deng National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academyof Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China GEPI Observatoire de Paris-Meudon 92195 Meudonl France College of Physical Science and Technology Shenyang Normal University Shenyang 110034China Univ Paris Diderot Sorbonne Paris Cit6 GEPI UMR8111 CNRS Observatoire de ParisF-92190 Meudon France

We select a large volume-limited sample of low surface brightness galax- ies （LSBGs, 2021） to investigate in detail their statistical properties and their dif- ferences from high surface brightness galaxies （HSBGs, 3639）. The distributions of stellar masses of LSBGs and HSBGs are nearly the same and they have the same me- dian values. Thus this volume-limited sample has good completeness and is further removed from the effect of stellar masses on their other properties when we compare LSBGs to HSBGs. We found that LSBGs tend to have lower stellar metallicities and lower effective dust attenuations, indicating that they have lower dust than HSBGs. The LSBGs have relatively higher stellar mass-to-light ratios, higher gas fractions, lower star forming rates （SFRs）, and lower specific SFRs than HSBGs. Moreover, with the decreasing surface brightness, gas fraction increases, but the SFRs and spe- cific SFRs decrease rapidly for the sample galaxies. This could mean that the star formation histories between LSBGs and HSBGs are different, and HSBGs may have stronger star forming activities than LSBGs.

关键词： galaxies fundamentalparameters--galaxies general--galaxies statis-tics -- galaxies stellar content

Discovery of four gravitational lensing systems by clusters in the SDSS DR6

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 5-10页

作者： Zhong-Lue Wen Jin-Lin Han Xiang-Yang Xu Yun-Ying Jiang Zhi-Qing Guo Peng-Fei Wang feng-shan liu National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China College of Science Guizhou University Guiyang 550025 China College of Physics Science and Technology Shenyang Normal University Shenyang 110034 China

We report the discovery of 4 strong gravitational lensing systems by visual inspections of the Sloan Digital Sky Survey images of galaxy clusters in Data Release 6 （SDSS DR6）. Two of the four systems show Einstein rings while the others show tangen- tial giant arcs. These arcs or rings have large angular separations （〉 8″） from the bright central galaxies and show bluer color compared with the red cluster galaxies. In addition, we found 5 probable and 4 possible lenses by galaxy clusters.

关键词： galaxies clusters general -- gravitational lensing

Hepatic steatosis with mass effect:A case report

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World Journal of Clinical Cases 2022年第30期10卷 11066-11073页

作者： Na Hu Shi-Jun Su Jin-Ye Li Hui Zhao shan-feng liu Lin-Sheng Wang Ruo-Zhen Gong Chuan-Ting Li Department of Radiology Shandong Provincial ENT HospitalShandong UniversityJinan 250023Shandong ProvinceChina Department of Radiology The Fifth People's Hospital of JinanJinan 250022Shandong ProvinceChina Innovation Studio Shandong Provincial ENT HospitalShandong UniversityJinan 250023Shandong ProvinceChina Department of Radiology Shandong Provincial HospitalShandong UniversityJinan 250021Shandong ProvinceChina

BACKGROUND Hepatic steatosis is a common radiologic *** imaging inklings are the absence of a mass effect,and there is currently no report of hepatic steatosis with mass *** SUMMARY A 23-year-old female was admitted due to a liver mass for half a *** obvious abnormalities were found in physical and laboratory ***,computed tomography,and magnetic resonance imaging showed a huge mass between the liver and stomach with a significant mass effect,and the caudate lobe and left lobe of the liver were *** signal on T2-and T1-weighted fat-saturated images of the mass was significantly reduced,and the enhanced scan showed inhomogeneous *** and pathological findings indicated the diagnosis of hepatic *** operation and re-review of the patient’s images showed that the lesion was supplied by the branch of the hepatic *** signal on T1-weighted out-of-phase images of the lesion was lower than on in-phase images,and there was no black rim cancellation artifact around the hepatic steatosis area on T1-weighted out-of-phase *** dynamic enhancement pattern of the lesion was similar to that of the adjacent normal liver *** above characteristics suggested that the lesion was hepatic ***,in this case,the lesion showed exogenous growth and was mass-like,with an obvious mass effect,which has not been reported *** Hepatic steatosis could grow exogenously and has an obvious mass *** needs to be distinguished from fat-rich *** T1-weighted in-and out-of-phase images and dynamic enhanced scanning are valuable for differential diagnosis of this lesion.

关键词： Hepatic steatosis Computed tomography Magnetic resonance imaging In-phase and out-of-phase imaging Case report

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变负载条件下柔性臂自适应预整形振动控制

浙江大学学报（工学版） 2012年第8期46卷 1520-1525页

作者：倪初锋刘山浙江大学工业控制研究所浙江杭州310027

针对单连杆柔性臂负载发生变化的情况,提出克服柔性臂末端振动的在线自适应输入预整形(OAPCA)方法.该方法将柔性臂连杆角速度的变化看作2阶振动模态的组合,在线设计前馈脉冲预整形输入,脉冲的时间和幅值由模态频率和阻尼值计算得到.当... 详细信息

针对单连杆柔性臂负载发生变化的情况,提出克服柔性臂末端振动的在线自适应输入预整形(OAPCA)方法.该方法将柔性臂连杆角速度的变化看作2阶振动模态的组合,在线设计前馈脉冲预整形输入,脉冲的时间和幅值由模态频率和阻尼值计算得到.当系统振动频率随负载变化后,预整形器失去振动抑制作用,将前馈输入整形控制、比例积分(PD)控制及快速傅里叶变换(FFT)算法相结合,设计自适应整形器抑制柔性臂末端振动.理论上证明OAPCA方法的可行性,并对频率失配的情况进行鲁棒性能分析,进行仿真研究.结果表明,柔性臂OAPCA方法具有良好的末端振动抑制能力和关节角跟踪能力,能够有效解决变负载单模态振动控制问题.

关键词：柔性臂自适应振动输入预整形

The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： Jieying Wu shan Ye Xiangyi liu Yingsheng Xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread

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环保投资在国民生产总值中所占比重的研究

华中理工大学学报 1988年第5期 41-48页

作者：冯珊刘翔华中理工大学自动控制工程系华中理工大学自动控制工程系

本文建立了把经济发展、人口增长与环境治理需求联系在一起的数学模型。运用系统工程的多目标线性规划框架构造了二级递阶优化的算法结构,从按15个产业部门编制的经济环境投入产出表出发,研究各部门环保投资占本部门最终产品的比重和各... 详细信息

本文建立了把经济发展、人口增长与环境治理需求联系在一起的数学模型。运用系统工程的多目标线性规划框架构造了二级递阶优化的算法结构,从按15个产业部门编制的经济环境投入产出表出发,研究各部门环保投资占本部门最终产品的比重和各部门对治理“三废”(废水、废气、废渣)的投资分配,进而在此基础上确定总环保投资占国民生产总值的合理比重。文中给出模型可用于工业行业的仿真实例及结果分析。

关键词：经济人口环境数学模型投入产出表环保投资仿真

Ru doping triggering reconstruction of cobalt phosphide for coupling glycerol electrooxidation with seawater electrolysis

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Journal of Energy Chemistry 2025年第1期100卷 317-326页

作者： Binglu Deng Jie Shen Jinxing Lu Chuqiang Huang Zhuoyuan Chen feng Peng Yunpeng liu School of Materials Science and Hydrogen Energy Foshan University School of Chemistry and Chemical Engineering Guangzhou University Guangdong Key Laboratory for Hydrogen Energy Technologies

Seawater electrolysis is a promising approach for sustainable energy without relying on precious ***,the large-scale seawater electrolysis is hindered by low catalytic efficiency and severe anode corrosion caused by the harmful *** contrast to the oxygen evolution reaction （OER）and chlorin ion oxidation reaction （ClOR）,glycerol oxidation reaction （GOR） is more thermodynamically and kinetically favorable ***,a Ru doping cobalt phosphide （Ru-CoP2） is proposed as a robust bifunctional electrocatalyst for seawater electrolysis and GOR,for the concurrent productions of hydrogen and value-added *** in situ and ex situ characterization analyses demonstrated that Ru doping featured in the dynamic reconstruction process from Ru-CoP2to Ru-CoOOH,accounting for the superior GOR *** coupling GOR with hydrogen evolution was realized by employing Ru-CoP2as both anode and cathode,requiring only a low voltage of 1.43 V at 100 mA cm-2,which was 250 m V lower than that in alkaline *** work guides the design of bifunctional electrocatalysts for energy-efficient seawater electrolysis coupled with biomass resource upcycling.

关键词： Glycerol electrooxidation Hydrogen evolution Ru doping Cobalt phosphide Bifunctional electrocatalysts