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The correction of diurnal effects on CSTAR photometry

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Research in Astronomy and Astrophysics 2014年第3期14卷 345-356页

作者： Song-hu wang xu Zhou hui Zhang ji-Lin Zhou hui-Gen Liu Ze-Yang meng jun Ma tian-meng Zhang Zhou Fan hu Zou Department of Astronomy & Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education Nanjing University National Astronomical Observatories Chinese Academy of Sciences

In January, 2008 the Chinese Small Telescope ARray （CSTAR） was suc-cessfully deployed at Dome A, Antarctica. Because CSTAR consists of four static14.5 cm telescopes pointing at the same 4.5° x 4.5° field around the south celestialpole, diurnal motion can be seen in its field of view. The stars are centered at differentpositions in different exposure frames. During four months of continuous observationsduring the polar night of 2008, about 0.3 million/-band images were obtained. In thelatest version of the released photometric catalog, the effects of diurnal motion of thestars on the static CSTAR optical system can be obviously found. In this work, weupdate the CSTAR catalog by carefully analyzing and correcting the systematic errorscaused by diurnal motion of stars on imperfectly flat-fielded frames.

关键词： methods: data analysis techniques: photometric

基于第一性原理和热力学计算的TiAl-Nb金属间化合物稳定性和相关系研究

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原子与分子物理学报 2025年第5期42卷 151-162页

作者：汪文洋徐勇田彬甘信柱王志刚梁永锋林均品山东建筑大学材料科学与工程学院济南250101 北京科技大学新金属材料国家重点实验室北京100083

采用基于广义梯度近似密度泛函理论的第一性原理计算和相图计算方法,研究了TiAl-Nb合金中γ、α_(2)、O_(2)和ωo相的热力学和力学性质以及相转变关系.研究表明,第一性原理计算得到的化合物相的参数是准确的,且分析结果与相图计算结果... 详细信息

采用基于广义梯度近似密度泛函理论的第一性原理计算和相图计算方法,研究了TiAl-Nb合金中γ、α_(2)、O_(2)和ωo相的热力学和力学性质以及相转变关系.研究表明,第一性原理计算得到的化合物相的参数是准确的,且分析结果与相图计算结果相一致.四个化合物相都是能够稳定存在的相.通过热力学和力学性质的分析,发现α_(2)相更容易转变为O_(2)相,并且在一定条件下可以通过相变反应生成ωo相.而γ相更容易转变为ωo相,但无法生成O_(2)相.

关键词： TiAl合金第一性原理相图声子谱及态密度热力学性质

Cellulose Acetate Thermoplastics with High Modulus, Dimensicnal Stability and Anti-migration Properties by Using CA-g-PLA as Macromolecular Plasticizer

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Chinese Journal of Polymer Science 2020年第10期38卷 1141-1148,I0008页

作者： Ru-meng xu tian-tian Yang Elvira Vidovic Ruo-Nan jia jin-Ming Zhang Qin-yong Mi jun Zhang CAS Key Laboratory of Engineering Plastis CAS Research/Education Center for Exellence in Molecular SciencesIstute of Chemistry.Chinese Academy of Sciences(CAS)Beijing 100190China University ofChinese Academy ofSciences Bejing 10049 China Faculty ofChemical Engineering and Technology.University ofZagreb Zagreb 1000Croatia

Cellulose diacetate(CDA)can be melt processed to produce numerous and widely-used plastic ***,due to the high glass transition temperature(Tg)of CDA,the addition of up to 30 wt%of micromolecular plasticizers is indispensable,which significantly reduces the dimensional stability and raises safety concerns from the migration of *** this work,a series of CDA-graft poly(lactic acid)(CDA-g-PLA)copolymers were synthesized by ring-opening polymerization of lactide onto the hydroxyI groups of *** resultant CDA-g-PLA copolymers possess adjustable degrees of substitution(DSpua)and side chain length(DPpLa)by controlling the reaction time and feed *** Tgs and thermal flow temperatures(Ts)of CDA-g-PLA strongly depend on DPpA such as the Tgs decrease linearly with the increase of *** CDA-g-PLA copolymers with the DPLA of 3-9 can be directly processed to transparent plastics by melt processing without any external plasticizers,because of their low Tfs of 170-215℃.More *** CDA-g PLA can act as the macromolecular *** obtained CDA/CDA-g-PLA has higher storage modulus,flexural modulus and Young's modulus than the commercial CDA plasticized with triethyl *** addition,the CDA/CDA-g PLA exhibits high dimensional stabilty and anti-migration *** a long term treatment at 80℃ and 60%humidity,the CDA/CDA-g-PLA can retain the initial ***,this work not only proposes a facile method for achieving a direct thermoplastic processing of CDA,but also provides a macromolecular plasticizer for CDA to make lightweight,stable and safer biobased thermoplastics.

关键词： Cellulose diacetate Thermoplastic processing Macromolecular plasticizer Poly(actic acid)

Effect of low-temperature ausforming on bainitic transformation and mechanical properties in ultrahigh-strength bainitic steel

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Journal of Iron and Steel Research International 2023年第9期30卷 1843-1853页

作者： tian-yu Zhang Ling-yu wang Yu wang jun hu Hong-shuang Di Wei xu State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

Low-temperature ausforming(LT-AF)prior to bainitic transformation leads to a noticeable acceleration of bainitic transformation kinetics;however,the effect of LT-AF on the retained austenite(RA)features and the resulting mechanical properties is still ***-AF was applied to ultrahigh-strength bainitic steel before *** deformation behavior and the resulting dislocation substructures were investigated by thermomechanical simulator and transmission electron microscopy(TEM).The planar dislocation structures produced during deformation at 350℃ accelerate the bainitic transformation kinetics during isothermal *** effect of LT-AF on the bainitic transformation kinetics and the features of RA was elucidated via dilatometer measurement,TEM,scanning electron microscopy,and X-ray *** is observed that LT-AF not only retains more RA content but also facilitates improved RA *** trend is mainly due to the large amounts of planar dislocations in RA and bainitic laths inherited from undercooled austenite caused by LT-AF,the decrease in bainitic sheaves size,and the increase in filmy RA content compared to the sample without ausforming.A large fraction of filmy RA with high stability and the refinement of bainitic sheaves obtained by LT-AF remarkably enhance the strain hardening capacity and achieve significantly better ductility compared to the directly austempered sample.

关键词： Ultrahigh-strength bainitic steel Bainitic transformation Low-temperature ausforming Retained austenite Strain hardening rate

Interface characteristics between TiN and matrix and their effect on solidification structure

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Journal of Iron and Steel Research International 2021年第9期28卷 1149-1158页

作者： tian-peng Qu De-yong wang hui-hua wang Dong Hou jun tian Shao-yan hu Li-juan Su Shagang School of Iron and Steel Soochow UniversitySuzhou215021JiangsuChina

Heterogeneous nucleation is an effective way to promote the dispersion and precipitation of second-phase particles in steel and refine the grain size of the solidification *** only refining as-cast structure grain size,but TiN in ferritic stainless steel can also pin grain boundaries and restrain the overgrowth of grains during *** interface characteristics between TiN and heterogeneous phases(high-melting inclusions and ferrite phase)were studied based on the wetting angles between molten steel with different compositions and TiN substrate,and on the matching degree between TiN and ferrite *** was found that,for the molten steel with the same composition,the wetting angle with the TiN substrate was significantly smaller than the contact angles with the other three substrates,while the wetting angle between ferrite phase and TiN was the *** lattice matching was compared among MgAl_(2)O_(4),TiN andδmatrix by means of a high-resolution transmission electron microscope,which revealed that a coherent or semi-coherent interface was formed between the crystal plane(400)of MgAl_(2)O_(4)and the crystal plane(200)of TiN,as well as between the crystal plane(200)of TiN and the crystal plane(110)ofδmatrix,with a lattice misfit of 5.1%and 3.4%,***,these two characteristics between TiN and ferrite phase were both explained from the perspective of interfacial *** microstructure refinement mechanism from high temperature to room temperature can be better reflected by the proposed wetting–lattice misfit theory.

关键词： TiN Heterogeneous nucleation Interfacial wetting Lattice matching Grain refinement

Consolidation mechanism of gold concentrates containing sulfur and carbon during oxygen-enriched air roasting

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 386-392页

作者： Qian Li Fang-zhou ji Bin xu jian-jun hu yong-bin Yang Tao jiang School of Minerals Processing and Bioengineering Central South University Changsha 410083 China

Consolidation in calcines is a common problem in the oxygen-enriched air roasting of refractory gold concentrates containing sulfur and carbon when the initial temperature is greater than 600°C. To determine the phases that caused consolidation, gold concentrates were roasted under different conditions and the calcines were mainly detected by X-ray diffraction (XRD). The possible underlying mechanism was then studied through comparisons of the XRD patterns of different calcines. The results indicated that the generation of calcium magnesium silicate, iron-doped calcium aluminosilicate, and calcium aluminate caused the consolidation. Furthermore, an enriched oxygen atmosphere accelerated the oxidation reaction and the emitted heat increased the local temperature in calcines. The local temperature was inferred to have increased to the generation temperature zone of the corresponding liquid phases. Oxidation of the pyrite and decomposition of the dolomite and muscovite mainly occurred at the initial stage of oxygen-enriched air roasting. Calcium was confirmed to be essential to the consolidation process. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Calcination Calcium Consolidation Gold Mechanisms Mica Oxygen Silicates Sulfur X ray diffraction

Multicolor photometry of the nearby galaxy cluster A119

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Research in Astronomy and Astrophysics 2012年第10期12卷 1381-1401页

作者： jin-Tao tian Qi-Rong Yuan xu Zhou Zhao-ji jiang jun Ma jiang-hua Wu Zhen-Yu Wu tian-meng Zhang hu Zou National Astronomical Observatories Chinese Academy of Sciences Beiiing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academyof Sciences Beijing 100012 China Department of Physics Nanjing Normal University Nanjing 210046 China Department of Astronomy Beijing Normal University Beijing 100875 China

This paper presents multicolor optical photometry of the nearby galaxy cluster Abell 119 （z = 0.0442） with the Beijing-Arizona-Taiwan-Connecticut system of 15 intermediate bands. Within the BATC field of view of 58＇× 58＇, there are 368 galaxies with known spectroscopic redshifts, including 238 member galaxies （called sample I）. Based on the spectral energy distributions of 1376 galaxies brighter than iBATC ---- 19.5, the photometric redshift technique and the color-magnitude relation of early-type galaxies are applied to select faint member galaxies. As a result, 117 faint galaxies were selected as new member galaxies. Combined with sample I, an enlarged sample （called sample II） of 355 member galaxies is obtained. Spatial distribution and localized velocity structure for two samples demonstrate that A119 is a dynami- cally complex cluster with at least three prominent substructures in the central region within 1 Mpc. A large velocity dispersion for the central clump indicates a merging along the line of sight. No significant evidence for morphology or luminosity segrega- tions is found in either sample. With the PEGASE evolutionary synthesis model, the environmental effect on the properties of star formation is confirmed. Faint galaxies in the low-density region tend to have longer time scales of star formation, smaller mean stellar ages, and lower metallicities in their interstellar medium, which is in agreement with the context of the hierarchical cosmological scenario.

关键词： galaxies: clusters: individual (A119)- galaxies: distances and redshifts-- galaxies: evolution-- galaxies: kinematics and dynamics-- methods: data analysis

Immunohistochemical characterization of hepatic stem cell-related cells in developing human liver

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Frontiers of Medicine 2007年第3期1卷 264-268页

作者： xu jun hu yong wang jian ZHOU ji ZHANG Taiping YU Hongyu Department of Pathology No.105 Hospital of PLAHefei 230031China Department of Obstetrics and Gynecology Second People’s Hospital of Yaohai DisctrictHefei 230011China Department of Pathology Changzheng HospitalSecond Military Medical UniversityShanghai 200003China

Little is known about the expression characteristics of the various kinds of possible markers in hepatic stem cells(HSCs)and other HSC-related cells in human fetal liver in various developmental *** is significant to investigate the immunohistochemical expression for better understanding of the origin,differentiation and migration of HSCs in the developing human liver.H-E staining and immunohistochemical methods were used to observe the expression of hepatic/cholangiocellular differentiation markers(AFP,GST-p,CK7,CK19)and hematopoietic stem cell markers(CD34 and c-kit)in several kinds of HSC-related cells in thirty cases of fetal liver samples(4–35 weeks after pregnancy).AFP expression appears in fetal hepatocytes at four weeks’*** peaks at 16–24 weeks’gestation and decreases gradually ***,weak signals were only found in some ductal plate cells and a few limiting plate ***-p was detected in hepatic cord cells from the sixth week and in the ductal plate cells from the eighth ***-six weeks later,only some ductal plate cells and a few limiting plate cells show positive ***19 expression peaks during the 6th–11th weeks in hepatic cord cells and decreases gradually afterwards,except for the ductal ***7 expression was limited in the ductal plate cells and bile ducts cells from the 14th ***34 and c-kit were detected at the eighth week in some ductal plate cells and a few mononuclear cells in the hepatic cords/mesenchymal tissue of portal *** 21 weeks,CD34 and c-kit were found only in ductal plate cells and a few mononuclear cells in the hepatic mesenchymal tissue of portal *** hepatocytes at 4–16 weeks’gestation are mainly constituted by HSCs characterized with bi-potential differentiation *** 16 weeks’gestation,most hepatic cord cells begin to differentiate into hepatocytes and abundant HSCs remain in ductal plate(the origin site of Hering canals).It is also indicated that the hematopoieti

关键词： fetal stem cells immunohistochemistry liver

Spontaneous positive exchange bias effect in SrFeO_(3-x)/SrCoO_(3-x) epitaxial bilayer

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Rare Metals 2021年第7期40卷 1858-1864页

作者： tian-Cong Su jun Zhang Wei Zhang Ying-Ying wang hui-hui ji Xiao-jiao wang Guo-Wei Zhou Zhi-yong Quan Xiao-Hong xu School of Chemistry and Materials Science Shanxi Normal UniversityLinfen 041004China Department of Chemistry and Chemical Engineering Lvliang UniversityLvliang 033001China Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education Linfen 041004China Research Institute of Materials Science Shanxi Normal UniversityLinfen 041004China Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology Linfen 041004China

A novel phenomenon of spontaneous positive exchange bias(PEB)is reported in SrFeO_(3-x)/SrCoO_(3-x) epitaxial bilayer without undergoing any magnetic field *** inserting a thick SrTiO3(STO)nonmagnetic spacer(about 6 nm)into the bilayer interface,this phenomenon still *** on a series of testing means,the spontaneous PEB effect is supposed to be mainly related to short-range ferromagnetic(FM)exchange coupling at the interface when there is no STO *** the STO interlayer reaches up to a certain thickness,shortrange coupling interaction basically *** this time,the long-range dipole field may be responsible for the coupling of the FM and antiferromagnetic(AFM)layer across the nonmagnetic STO and then leads to the same bias *** discoveries provide a new way to realize and manipulate spontaneous exchange bias-based spintronics devices,such as magnetic recording heads and spin valves.

关键词： SrFeO_(3-x)/SrCoO_(3-x)bilayer Spontaneous positive exchange bias long-range dipole field Exchange coupling