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Predicting Supermassive Black Hole Mass with Machine Learning Methods

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Research in Astronomy and Astrophysics 2022年第8期22卷 182-190页

作者： Yi He Qi Guo shi shao Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

It is crucial to measure the mass of supermassive black holes(SMBHs)in understanding the co-evolution between the SMBHs and their host *** methods usually require spectral data which are expensive to *** use the AGN catalog from the Sloan Digital Sky Survey project Data Release 7(DR7)to investigate the correlations between SMBH mass and their host galaxy *** apply the machine learning algorithms,such as Lasso regression,to establish the correlation between the SMBH mass and various photometric properties of their host *** find an empirical formula that can predict the SMBH mass according to galaxy luminosity,colors,surface brightness,and *** root-mean-square error is 0.5 dex,comparable to the intrinsic scatter in SMBH mass *** 1σscatter in the relation between the SMBH mass and the combined galaxy properties relation is 0.48 dex,smaller than the scatter in the SMBH mass versus galaxy stellar mass *** relation could be used to study the SMBH mass function and the AGN duty cycles in the future.

关键词： (galaxies:)quasars:supermassive black holes galaxies:evolution methods:data analysis

Study on the diamond/ultrafine WC-Co cermets interface formed in a SPS consolidated composite

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Rare Metals 2006年第2期25卷 150-155页

作者： shi Xiaoliang shao Gangqin DUAN Xinglong YUAN Runzhang State Key Laboratory of Advanced Technology for Materials Synthesis ＆ Processing Wuhan University of Technology Wuhan 430070 China

Nanocrystalline WC-Co composite powder and coated tungsten diamond by using vacuum vapor deposition were consolidated by the spark plasma sintering （SPS） process to prepare diamond-enhanced WC-Co cemented carbide composite materials. The interface microstructures between coated tungsten diamond and WC-Co cemented carbide matrix were investigated by scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDXS）. The results showed that there is a transitional layer between the diamond and the matrix, in which the carbon content is 62.97wt.%, and the content of cobalt in the transitional zone is 6.19wt.%; the content of cobalt in the WC-Co cemented carbide matrix is 6.07wt.%, in which the carbon content is 15.95wt.%, and the content of cobalt on the surface of diamond is 7.30wt.%, in which the carbon content is 80.38wt.%. The transitional zone prevents the carbon atom of the diamond from spreading to the matrix, in which the carbon content does coincide with the theoretical value of the raw nanocomposite powders, and the carbon content forms a graded distribution among the matrix, transitional zone, and the surface of diamond; after the 1280℃ SPS consolidated process the diamond still maintains a very good crystal shape, the coated tungsten on the surface of the diamond improves thermal stability of the diamond and increases the bonding strength of the interface between the diamond and the matrix.

关键词： diamond nanocrystalline WC-Co composite powders interface spark plasma sintering

Atomic force microscope study of WC-10Co cemented carbide sintered from nanocrystalline composite powders

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Journal of University of Science and Technology Beijing 2005年第6期12卷 558-563页

作者： Xiaoliang shi Gangqin shao Xinglong Duan Runzhang Yuan State Key Laboratory of Advanced Technology for Materials Synthesis ＆ Processing Wuhan University of Technology Wuhan 430070 China

In order to compare the spark plasma sintedng （SPS） process plus hot isostatic press （HIP） with vacuum sintedng plus HIP, an investigation was carried out on the topography, microstructure and gain size distribution of nanocrystalline WC-10Co composite powder and the sintered specimens prepared by SPS plus HIP and by vacuum sintering plus HIP by means of atomic force microscopy （AFM）. The mechanical properties of the sintered specimens were also investigated. It is very easy to find cobalt lakes in the specimen prepared by vacuum sintering plus HIP process. But the microstructure of the specimen prepared by SPS plus HIP is more homogeneous, and the grain size is smaller than that prepared by vacuum sintering plus HIP. The WC-10Co ultrafine cemented carbide consolidated by SPS plus HIP can reach a relative density of 99.4%, and the transverse rupture strength （TRS） is higher than 3540 MPa, the Rockwell A hardness （HRA） is higher than 92.8, the average grain size is smaller than 300 nm, and the WC-10Co ultrafine cemented carbide with excellent properties is achieved. The specimen prepared by SPS with HIP has better properties and microstructure than that prepared by vacuum sintering with HIP.

关键词： WC-10Co nanocrystalline composite powder atomic force microscopy (AFM) spark plasma sintering (SPS) hot isostatic pressing (HIP)

Colorimetric Detection of Aniline Based on Di(hydroxymethyl)- di-(2-pyrrolyl)methane-TCNQ System

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Chinese Chemical Letters 2006年第3期17卷 377-379页

作者： Jian XU Yong GUO shi Jun shao Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000

The blue color system of supramolecular assembly formed by di（hydroxymethyl）- di-（2-pyrrolyl）methane and tetracyanoquinodimethane （TCNQ） may be used for effective and selective detection of aniline through the visual color change in CH3CN/H2O mixed solvent. The excellent properties of the system make the supramolecular assembly to be a highly selective colodmetric probe for aniline.

关键词： Dipyrromethane charge-transfer complex aniline detection sensor.

New applications of poly(arylene ether)s in organic light-emitting diodes

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Chinese Chemical Letters 2016年第8期27卷 1201-1208,1466页

作者： shi-Yang shao Jun-Qiao Ding Li-Xiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

Compared with conventional π-conjugated polymers,poly（arylene ether）s（PAEs） may take advantages of excellent thermal properties,well-defined effective conjugated length and no catalyst ***,their applications have been extended from engineering plastics to optoelectronic *** this review,various kinds of functional PAEs used as fluorescent polymers,host polymers and phosphorescent polymers in organic light-emitting diodes（OLEDs） are outlined,and their molecular design,synthesis and device performance are overviewed.

关键词： Poly(arylene ether)s Organic light-emitting diodes Fluorescent polymers Host polymers Phosphorescent polymers

Subhalo Abundance and Satellite Spatial Distribution in Milky Way-Andromeda-like Paired Haloes

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Research in Astronomy and Astrophysics 2022年第12期22卷 344-352页

作者： Kemeng Li shi shao Ping He Qing Gu Jie Wang College of Physics Jilin UniversityChangchun 130012China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Center for High Energy Physics Peking UniversityBeijing 100871China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

We study the subhalo and satellite populations in haloes similar to the Milky Way(MW)-Andromeda paired configuration in the Millennium II and P-Millennium *** find subhaloes are 5%–15%more abundant in paired haloes than their isolated counterparts that have the same halo mass and large-scale environmental *** haloes tend to reside in a more isotropic environment than isolated haloes,the shear tensor of their large-scale tidal field is possibly responsible for this *** also study the thickness of the spatial distribution of the top 11 most massive satellite galaxies obtained in the semi-analytic galaxy sample constructed from the Millennium II ***,satellites that have lost their host subhaloes due to the resolution limit of the simulation have been taken into *** a result,we find that the difference in the distribution of the satellite thickness between isolated and paired haloes is indistinguishable,which suggests that the paired configuration is not responsible for the observed plane of satellites in the *** results in this study indicate the paired configuration could bring some nonnegligible effect on the subhalo abundance in the investigation of the MW's satellite problems.

关键词： galaxies:abundances galaxies:halos galaxies:structure (galaxies:)Local Group (cosmology:)dark matter methods:numerical

Development of an innovative detection system for pebble bed kinematic studies

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Nuclear Science and Techniques 2016年第2期27卷 115-121页

作者： Ying Zhao shi-Xiang Qu Xing-Wang Zhu shi-Wei shao Zhao-Zhong He Kun Chen Shanghai Institute of Applied Physics Chinese Academy of Sciences Jiading Campus Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

Pebble bed reactors enable the circulation of pebble fuel elements when the reactors are in *** unique design helps to optimize the burnup and power distribution, reduces the excessive reactivity of the reactor,and provides a mean to identify and segregate damaged fuel elements during operation. The movement of the pebbles in the core, or the kinematics of the pebble bed,significantly affect the above features and is not fully understood. We designed and built a detection system that can measure 3-axis acceleration, 3-axis angular velocity,3-axis rotation angles, and vibration and temperature of multiple pebbles anywhere in the pebble bed. This system uses pebble-shaped detectors that can flow with other pebbles and does not disturb the pebble movement. We used new technologies to enable instant response, precise measurement, and simultaneous collection of data from a large number of detectors. Our tests show that the detection system has a negligible zero drift and the accuracy is better than the designed value. The residence time of the pebbles in a moving pebble bed was also measured using the system.

关键词：检测系统卵石床运动学创新精确测量燃料元件反应堆设计值

Diabetic mastopathy in an elderly woman misdiagnosed as breast cancer: A case report and review of the literature

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World Journal of Clinical Cases 2021年第14期9卷 3458-3465页

作者： Xiao-Xiao Chen shi-Jun shao Hua Wan Department of Breast Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 200001China

BACKGROUND Diabetic mastopathy is a rare benign disease in clinical practice that mainly occurs in young and middle-aged women with type 1 *** has also been reported that this disease can be found in patients with type 2 diabetes and other autoimmune diseases,such as Hashimoto's thyroiditis,as well as in *** pathogenesis of diabetic mastopathy is not yet clear,and it is easily confused with breast cancer due to their similar clinical manifestations and imaging *** SUMMARY A 69-year-old female patient was admitted because of painless breast masses,with a history of type 2 *** imaging and physical examination suggested a high risk of breast *** histopathological analysis showed dense lymphocytes infiltrating around the lobules of the breast,and extensive fibrosis of the surrounding ***,diabetic mastopathy was *** The diagnosis of diabetic mastopathy in elderly patients with painless breast masses is difficult to distinguish from breast cancer,and its imaging manifestations are not specific.

关键词： Diabetic mastopathy Diabetes Mammary gland disease Literature review Autoimmunity Case report

Effect of Sb dopant amount on the structure and electrocatalytic capability of Ti/Sb-SnO_2 electrodes in the oxidation of 4-chlorophenol

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Journal of Environmental Sciences 2007年第11期19卷 1380-1386页

作者： KONG Jiang-tao shi shao-yuan ZHU Xiu-ping NI Jin-ren Key Laboratory of Water and Sediment Sciences Ministry of Education of China Department of Environmental Engineering Peking University Beijing 100871 China State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

Ti/Sb-SnO2 anodes were prepared by thermal decomposition to examine the influence of the amount of Sb dopant on the structure and electrocatalytic capability of the electrodes in the oxidation of 4-chlorophenol. The physicochemical properties of the Sb-SnO2 coating were markedly influenced by different amounts of Sb dopant. The electrodes, which contained 5% Sb dopant in the coating, presented a much more homogenous surface and much smaller mud-cracks, compared with Ti/Sb-SnO2 electrodes containing 10% or 15% Sb dopant, which exibited larger mud cracks and pores on the surface. However, the main microstructure remained unchanged with the addition of the Sb dopant. No new crystal phase was observed by X-ray diffraction （XRD）. The electrochemical oxidation of 4-chlorophenol on the Ti/SnO2 electrode with 5% Sb dopant was inclined to electrochemical combustion; while for those containing more Sb dopant, intermediate species were accumulated. The electrodes with 5% Sb dopant showed the highest efficiency in the bulk electrolysis of 4-chlorophenol at a current density of 20 mA/cm^2 for 180 min; and the removal rates of 4-chlorophenol and COD were 51.0% and 48.9%, respectively.

关键词： 4-chlorophenol cyclic voltammogram electrochemical oxidation Sb dopant Ti/Sb-SnO2 electrode