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Kinematic properties of the dual AGN system J0038+4128 based on long-slit spectroscopy

Research in Astronomy and Astrophysics 2016年第3期16卷 43-50页

作者： yang-Wei Zhang yang Huang Jin-ming Bai Xiao-Wei Liu jian-Guo Wang Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China University of Chinese Academy of Sciences Beijing 100049China

The study ofkiloparsec-scale dual active galactic nuclei （AGN） provides important clues for understanding the co-evolution between host galaxies and their central supermassive black holes undergoing a merging process. We present long-slit spectroscopy of J0038 ＋4128, a kiloparsec-scale dual AGN candidate, discovered recently by Huang et al., using the Yunnan Faint Object Spectrograph and Camera （YFOSC） mounted on the Lijiang 2.4-m telescope administered by Yunnan Observatories. From the long-slit spectra, we find that the average relative line-of-sight （LOS） velocity between the two nuclei （J0038＋4128N and J0038＋4128S） is about 150 km s-1. The LOS velocities of the emission lines from the gas ionized by the nuclei activities and of the absorption lines from stars governed by the host galaxies for different regions of J0038＋4128 exhibit the same trend. The same trend in velocities indicates that the gaseous disks are co-rotating with the stellar disks in this ongoing merging system. We also find several knots/giant H II regions scattered around the two nuclei with strong star formation revealed by the observed line ratios from the spectra. Those regions are also clearly detected in images from HST F336W/U-band and HST F555W/V-band.

关键词： techniques: spectroscopic -- galaxies: kinematics and dynamics -- galaxies: active -- galax- ies: interactions -- galaxies: nuclei -- galaxies: individual (J0038+4128)

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Raman scattering under extreme conditions

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Chinese Physics B 2018年第7期27卷 120-132页

作者： Feng Jin yang yang An-Min Zhang jian-Ying Ji Qing-ming Zhang Department of Physics Renmin University of ChinaBeijing 100872China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Science and Technology Lanzhou UniversityLanzhou 730000China

Raman scattering is a versatile and powerful technique and has been widely used in modern scientific research and vast industrial applications. It is one of the fundamental experimental techniques in condensed matter physics, since it can sensitively probe the basic elementary excitations in solids like electron, phonon, magnon, etc. The application of extreme conditions （low temperature, high magnetic field, high pressure, etc.） to Raman scattering, will push its capability up to an unprecedented level, because this enables us to look into new quantum phases driven by extreme conditions, trace the evolution of the excitations and their coupling, and hence uncover the underlying physics. This review contains two topics. In the first part, we will introduce the Raman facility under extreme conditions, belonging to the optical spectroscopy station of Synergetic Extreme Condition User Facilities （SECUF）, with emphasis on the system design and the capability the facility can provide. Then in the second part we will focus on the applications of Raman scattering under extreme conditions to a variety of condensed matter systems such as superconductors, correlated electron systems, charge density waves （CDW） materials, etc. Finally, as a rapidly developing technique, time-resolved Raman scattering will be highlighted here.

关键词： Raman scattering technique extreme conditions correlated electron systems time-resolved Ra-man scattering

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Corrosion behaviour of NiCrFeAl-hBN seal coatings in oxidation environments at a high temperature

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Rare Metals 2021年第1期40卷 212-218页

作者： Su-Yuan yang Dan Guo Xing-Wang Cheng jian-ming Liu Yue-Guang Yu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081.China National Key Laboratory of Science and Technol Beijing General Research

The purpose of this investigation was to evaluate the microstructure,high-temperature oxidation behaviour,and hardness of a seal coating under controlled exposures at 750℃with different exposure *** results reveal that the main phases in the coating are Ni,FeNi3,and hexagonal BN,withα-Al_(2)O_(3)peaks appearing after 2-h *** the exposure time increases,the diffraction peak intensity ofα-Al_(2)O_(3)begins to decrease and Cr_(2)O_(3)peaks appear after 200 *** 1000 h,Cr_(2)O_(3)becomes dominant with only small amounts ofα-Al_(2)O_(3)*** high-temperature oxidation process of the coating includes three stages:the fast stage,transition stage,and slow *** oxidation rate is constant in each stage,and in the fast stage and slow stages with values of7.9×10^(-4)and 8.37×10^(-5)mg^(2)·cm^(-4)·s^(-1),***,α-Al_(2)O_(3)forms near the pores in the coating,followed by the formation of Cr_(2)O_(3).As the exposure time increases,oxidation penetrates into the interior of the coating along phase boundaries to form island-shaped inner oxide layers with high concentrations of Cr,Ni,and ***,hardness increases with increasing oxide percentage.

关键词： NiCrFeAl-hBN Seal coating Oxidation Microstructure High temperature

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Effects of moss-dominated biocrusts on soil detachment by overland flow in the Three Gorges Reservoir Area of China

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Journal of Mountain Science 2020年第10期17卷 2418-2431页

作者： ZHANG Guan-hua DING Wen-feng PU jian LI jian-ming QIAN Feng SUN Bao-yang Soil and Water Conservation Department Changjiang River Scientific Research InstituteWuhan430010China Research Center on Mountain Torrent&Geologic Disaster Prevention of Ministry of Water Resources Wuhan430010China

Biological soil crusts(biocrusts)are important landscape components that exist in various climates and *** roles of biocrusts in numerous soil processes have been predominantly recognized in many dryland regions ***,little is known about their effects on soil detachment process by overland flow,especially in humid *** study quantified the effects of moss-dominated biocrusts on soil detachment capacity(Dc)and soil erosion resistance to flowing water in the Three Gorges Reservoir Area which holds a subtropical humid *** factors driving soil detachment variation and their influencing mechanism were analyzed and *** designed five levels of coverage treatments(1%–20%,20%–40%,40%–60%,60%–80%,and 80%–100%)and a nearby bare land as control in a mossdominated *** soil samples were taken and subjected to water flow scouring in a hydraulic flume under six shear stresses ranging from 4.89 to 17.99 *** results indicated that mean Dc of mosscovered soil varied from 0.008 to 0.081 kg m^-2 s^-1,which was 1.9 to 21.0 times lower than that of bare soil(0.160 kg m^-2 s^-1).Rill erodibility(Kr)of mosscovered soil ranged from 0.0095 to 0.0009 s m^-1,which was 2 to 20 times lower than that of bare soil(0.0187 s m^-1).Both relative soil detachment rate and Kr showed an exponential decay with increasing moss coverage,whereas the critical shear stress(τc)for different moss coverage levels did not differ *** coverage,soil cohesion,and sand content were key factors affecting Dc,while moss coverage and soil bulk density were key factors affecting Kr.A power function of flow shear stress,soil cohesion,and moss coverage fitted well to estimate Dc(NSE=0.947).Our findings implied that biocrusts prevented soil detachment directly by their physical cover and indirectly by soil properties *** could be rehabilitated as a promising soil conservation measure during ecological recovery to enhance so

关键词： Soil detachment Soil erosion resistance Rill erodibility Biological soil crusts yangtze River

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Corrosion Behavior of the Ni-Cr-Fe Base Superalloy GH984G in a Synthetic Coal Ash and Flue Gas Environment

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 863-868页

作者： Guang-ming Liu Hua-Chun yang Qin Liang Xiao-Chuan yang Shan-Ping Ren jian-Hang Huang School of Materials Science and Engineering Nanchang Hangkong University Dongfang Boiler Group Co. Ltd Material Research Institute

The corrosion behavior of the new Ni-Cr-Fe base superalloy GH984G in a synthetic coal ash and flue gas environments was studied at 700 ℃. The results showed that the corrosion rate was slow during the initial corrosion stage, then followed by a stage of faster mass loss. During the corrosion test, the scale trended to spall slightly, resulting in the formation of corrosion pits on the sample surfaces. The main corrosion products were identified as NiFeCrO4 and a small amount of Cr2O3. The scale microstructure involved the presence of three corrosion layers. The outer layer contained Cr, Ni, Fe, O and a small amount of S. Many micro-cracks were detected in the Cr-rich intermediate oxide layer. The inner corrosion layer was thin and rich in S. Internal sulfidation and internal oxidation occurred in the substrate. Because of its relatively high Cr content, the GH984G superalloy exhibited a good corrosion resistance under the test conditions.

关键词： Ni-Fe-Cr base superalloy Coal ash SO2 Corrosion

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在线式PIV系统应用于旋流射流的研究

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天津大学学报（自然科学与工程技术版） 2001年第5期34卷 674-677页

作者：汪剑鸣杨延相刘昌文刘杰天津大学电气自动化与能源工程学院天津300072 天津大学内燃机燃烧学国家重点实验室天津300072 天津大学机械工程学院天津300072

开发了一套在线式粒子图像测速系统 ( PIV) ,并用水杯中水涡流实验验证了系统的可靠性 .利用该系统研究了旋流喷嘴射流的液滴运动速度 ,在线得到喷雾流场的双脉冲曝光数字化图像 ,即时用系统软件的图像分析模块进行分析 ,得到旋流喷嘴... 详细信息

开发了一套在线式粒子图像测速系统 ( PIV) ,并用水杯中水涡流实验验证了系统的可靠性 .利用该系统研究了旋流喷嘴射流的液滴运动速度 ,在线得到喷雾流场的双脉冲曝光数字化图像 ,即时用系统软件的图像分析模块进行分析 ,得到旋流喷嘴喷雾场的两维速度分布 .但在喷嘴近区域内得不到合理的速度结果 ,原因是该区域内液体未雾化成液滴 .液滴速度都小于理论喷射速度 ,且沿喷射方向呈减小趋势 ,表明液体在破碎成液滴后速度一直衰减 .旋流喷嘴射流轴线中心区域速度有一极小值。

关键词：粒子图像测速系统图像处理旋流喷嘴液体雾化旋流射流喷雾流场内燃机

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Optimization of Uncertain Structures with Interval Parameters Considering Objective and Feasibility Robustness

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 124-136页

作者： Jin Cheng Zhen-Yu Liu jian-Rong Tan yang-Yan Zhang ming-yang Tang Gui-Fang Duan State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang University State Key Laboratory of CAD&CG Zhejiang University Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education Harbin Institute of Technology

For the purpose of improving the mechanical performance indices of uncertain structures with interval parameters and ensure their robustness when fluctuating under interval parameters, a constrained interval robust optimization model is constructed with both the center and halfwidth of the most important mechanical performance index described as objective functions and the other requirements on the mechanical performance indices described as constraint functions. To locate the optimal solution of objective and feasibility robustness, a new concept of interval violation vector and its calculation formulae corresponding to different constraint functions are proposed. The math?ematical formulae for calculating the feasibility and objective robustness indices and the robustness?based preferential guidelines are proposed for directly ranking various design vectors, which is realized by an algorithm integrating Kriging and nested genetic algorithm. The validity of the proposed method and its superiority to present interval optimization approaches are demonstrated by a numerical example. The robust optimization of the upper beam in a high?speed press with interval material properties demonstrated the applicability and effectiveness of the proposed method in engineering.

关键词： Robust optimization Uncertain structure Interval violation vector Feasibility robustness Objective robustness Nested genetic algorithm

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Clinical features, outcomes and treatment-related pneumonitis in elderly patients with esophageal carcinoma

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World Journal of Gastroenterology 2014年第36期20卷 13185-13190页

作者： jian He Zhao-Chong Zeng Shi-ming Shi Ping yang Department of Radiation Oncology Zhongshan Hospital Fudan University

AIM: To investigate the clinical features and prognoses of elderly patients with esophageal carcinoma and to compare the effects of radiotherapy and rates of treatment-related pneumonitis (TRP) between elderly and non... 详细信息

关键词： Esophageal carcinoma Radiation therapy Elderly patients Treatment-related pneumonitis Survival rate

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Pyrometallurgical recycling of stainless steel pickling sludge: a review

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Journal of Iron and Steel Research International 2019年第6期26卷 547-557页

作者： Cong-cong yang jian Pan De-qing Zhu Zheng-qi Guo Xiao-ming Li School of Minerals Processing and Bioengineering Central South University Changsha 410083 Hunan China School of Metallurgical Engineering Xi'an University of Architecture and Technology Xi'an 710055 Shaanxi China

Stainless steel pickling sludge (SSPS), generated from the lime neutralization process of spent pickling liquor, is classified as a hazardous waste consisting of abundant metals like Fe, Cr and Ni, and other elements like F, S and Na, etc. Rather than a common disposal in landfill, recovering these metals and other valuable components from SSPS can not only create economic benefits, but also eliminate its adverse impacts on human health and the environment. A review of the formation mechanism and basic properties of SSPS was made, and the technical features, advantages and limitations of a series of pyrometallurgical treatment processes were summarized. Based on these, the main challenges for recycling of SSPS through the existing techniques are demonstrated. The traditional pelletizing/sintering-blast furnace process can only be used as a partial solution. Direct use of SSPS as flux in an argon-oxygen decarburization converter or electric arc furnace is a promising way, but low S sludges are preferred. The STAR process shows excellent recovery for metals, but it also has a low tolerance to the S and F contents in SSPS. And theINMETCO process is highly flexible in treatment of various wastes, whereas it exhibits relatively low Cr recovery and produces poor-quality pig iron. In addition, the feasibility of the rotary kiln-electric furnace, solid -state reduction of chromite and reduction-magnetic separation processes requires further studies. An urgent task at present is to develop a system for scientific classification and separate collection of SSPS in terms of chemical composition, notably S and F contents.

关键词： Stainless steel pickling sludge Hazardous waste Recycling Pyrometallurgical process Reduction Recovery

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Formation of G-phase in 20Cr32Ni1Nb Stainless Steel and its Effect on Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 829-839页

作者： Xiao-Feng Guo Ying-Ying Ni jian-ming Gong Lu-yang Geng jian-Qun Tang Yong jiang Xian-Kai Jia Xin-Yu yang School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China Key Lab of Design and Manufacture of Extreme Pressure Equipment Nanjing 210037China

A series of tensile tests, Charpy impact tests, optical microscopy observations, and field emission-scanning electron microscopy examinations, were carded out to investigate the mechanical properties and microstructural evolution of 20Cr32NilNb steel. Experimental results indicate that the as-cast microstructure of the steel typically consists of a supersaturated solid solution of austenite matrix with a network of interdendritic primary carbides （NbC and M23C6）. In the ex-service samples, large amounts of secondary carbides precipitate within austenite matrix. Besides the growth and coarsening of NbC and M23C6 carbides during service condition, the Ni-Nb silicides known as G-phase （Nil6Nb6Si7） are formed at the interdendritic boundaries. The microstructural evolution results in the degradation of the mechanical properties of the ex-service steel. In addition, the precipitate rate of G-phase, depending in part on Si content, varies greatly for the 20Cr32NilNb steel, which plays a key role in the long-term microstructural stability of the steel. Based on the X-ray diffraction data, time-temperature-transformation curve for the steel is obtained from the aged specimens.

关键词： 20Cr32NilNb Embrittlement G-phase TTT dial, ram

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