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IRAS F21013-0739:a possible evolutionary successor of an ultraluminous infrared galaxy

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Research in Astronomy and Astrophysics 2011年第4期11卷 419-433页

作者： xian-Min meng hong Wu Chen Cao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Shandong University at Weihai Weihai 264209 China

We present a stellar population synthesis study of a type II luminous infrared galaxy, IRAS F21013-0739. Optical images show clear characteristics of a merger remnant. The H-band absolute magnitude is MH = -25.1, which is -2 times as luminous as L＊ galaxies. Stellar populations are obtained through the stellar synthesis code STARLIGHT. We find that it experienced a recent starburst （SB） phase - 100 Myr ago. By reconstructing the ultraviolet-to-optical spectrum, and adopting Calzetti et al. and Leitherer et al.＇s extinction curves, we estimate the past infrared （IR） luminosities of the host galaxy and find it may have experienced an ultraluminous infrared galaxy phase which lasted for about 100 Myr. Its i-band absolute magnitude is Mi = -22.463, and its spectral type shows type 2 active galactic nucleus （AGN） characteristics. The mass of the supermassive black-hole is estimated to be MBH = 1.6 × 107 M⊙ （lower- limit）. The Eddington ratio Lbol/LEdd is 0.15, which is typical of Palomar-Green （PG） quasars. Both the nuclear SB and AGN contribute to the present IR luminosity budget, and the SB contributes -67%. On the diagram of IR color versus IR/opfical excess, it is located between IR quasars and PG quasars. These results indicate that IRAS F21013-0739 has probably evolved from a ULIRG, and it can possibly evolve into an AGN.

关键词： infrared galaxies -- galaxies evolution -- galaxies starburst --galaxies: individual (IRAS F21013-0739) -- galaxies stellar content

Assessments of the Arctic amplification and the changes in the Arctic sea surface

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Advances in Climate Change Research 2019年第4期10卷 193-202页

作者： CHEN Jin-Lei KANG Shi-Chang meng xian-hong YOU Qing-Long State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Centre fo r Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing100101China Key Laboratory of Land Surface Processes and Climate Change Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Institute of Atmospheric Sciences Fudan UniversityShanghai200433China

Although dramatic warming is occurring in the Arctic,it is incomplete to provide an estimate to the Arctic Amplification(AA)based only on the surface air temperature(SAT)obtained at a few land *** this study,a comprehensive evaluation has been made with sea surface temperature(SST)and SAT from the Arctic land and ***,the variations of sea surface parameters were analyzed for a better understanding of the updated Arctic changes in recent *** was underestimated by 4.3%when only considering the *** 1982—2018,the Arctic and global SSTs increased dramatically after 2002 with a near-synchronous trend in 2011—*** ice extent exhibited negative anomalies in September and March after 2002,which were more significant in *** warming was more remarkable in March than that in September,and the negative SST anomaly entirely disappeared in March in the last two years(2017—2018).However,sea ice thickness and snow depth in September increased with the positive anomaly in the southwestern Arctic Ocean.

关键词： Arctic Warming Arctic amplification Sea ice Snow depth

Synthesis of Ladder-like Polyphenylsilsesquioxanes with Fairly High Regularity Using 1,2-Ethylenediamine as Endo-template

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Chinese Journal of Polymer Science 2015年第9期33卷 1305-1312页

作者：杨雄发 Cheng Cao Zhong-hong Chen Jia Liu meng-xian Luo 来国桥 Key Laboratory of Organosilicon Chemistry and Material Technology of Education Ministry Hangzhou Normal University Department of Materials Science and Engineering Zhejiang University

Ladder-like polyphenylsilsesquioxanes with fairly high regularity were synthesized using an endo-template 1,2-ethylenediamine at mild temperature via direct co-hydrolysis and condensation reactions in the presence of acid catalysts in the mixture of 1,4-dioxane/H20. The features for synthesis of ladder-like polyphenylsilsesquioxanes were investigated in detail. The products obtained were characterized by FTIR, SEC, XRD and NMR.

关键词： Ladder-like Poly(phenyl silsesquioxanes) Endo-template.

Characteristic analysis of a Smith–Purcell terahertz source

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Photonics Research 2016年第5期4卷 162-167页

作者： xian-Zhu meng Ming-hong Wang Li-Ming Zhang Zhong-Min Ren Shandong Provincial Key Laboratory of Optical Communication Science and Technology School of Physics Science and Information Engineering Liaocheng University

We investigate a novel Smith–Purcell terahertz source. This device is composed of an electron gun, a cylindrical resonator, a metallic grating, and a collector. The characteristics of the Smith–Purcell terahertz source are discussed with the help of three-dimensional particle-in-cell simulation. In this device, coherent and high-power Smith–Purcell radiation(SPR) at the terahertz frequency range can be produced for the reasonable parameters of charge energy and grating. Our results indicate that coherent SPR at 506.529 GHz with a power around 1000 W can be obtained for a grating of period l=0.3 mm operating at the beam energy E=50 keV and beam current I=10 A.

关键词： cell THz Purcell terahertz source Characteristic analysis of a Smith

Identification and Quantitative Analysis of Significantly Accumulated Proteins During the Arabidopsis Seedling De-etiolation Process

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Journal of Integrative Plant Biology 2006年第1期48卷 104-113页

作者： Bai-Chen Wang Ying-hong Pan Da-Zhe meng Yu-xian Zhu The National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing 100871 China

Proteomic analysis was performed on seedlings after different light treatments. A total of （1 350±31） protein spots was separated and visualized on each silver nitrate-stained two-dimensional gel using protein samples prepared from light-grown or etiolated seedlings with or without 6-9 h light treatment. Twenty-five protein spots （encoded by 19 genes） that were significantly accumulated upon light treatment were identified using the matrix-assisted laser desorption ionization time-of-flight mass spectrometry method. Functional proteomics indicated that these proteins involved mainly in chloroplast development, energy metabolism, cell cycle progression and membrane electron transport. For 18 of the protein-coding genes we identified through an internet search, the transcript levels of 17 genes matched roughly with their protein content in etiolated and green seedlings, suggesting that these genes were regulated by light mainly at the transcriptional level. Despite a very significant increase in the amount of proteins upon light treatment, similar RNA levels were found in dark-grown or green seedlings for the carbonic anhydrase gene At3g05100, indicating a possible post-transcriptional regulatory mechanism. Elucidation of light-induced protein accumulation will undoubtedly enhance our understanding of plant photomorphogenesis.

关键词： Arabidopsis de-etiolation light two-dimensional electrophoresis.

Specific Expression of a Novel Nodulin GmN479 Gene in the Infected Cells of Soybean (Glycine max) Nodules

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Agricultural Sciences in China 2011年第10期10卷 1512-1524页

作者： CHENG xian-guo WANG Li WANG He YU Guo-hong BAI You-lu LIU meng-meng Key Laboratory of Crop Nutrition and Fertilizer Agriculture of Ministry/Insititute of Agricultural Resource and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Shanxi Normal University College of Life Science Linfen 041004 P.R. China

A novel nodulin gene, GmN479 genomic clone composing of 3 630 nucleotides was isolated from mature soybean nodules using GmN479 cDNA as a probe by subtractive hybridization procedure. GmN479 encodes 170 amino acids with 2.09 kb nucleotides promoter region, and contains two important upstream promoter elements, one is a conserved cis-acting sequence motif 5′-AAAGAT-3′ controlling nodulin gene expression, and the other is typical CAAT boxes. GmN479 gene has a single zinc-finger C2H2 domain YSCAFCQRGFSNAQALLGGHMNIH and a conserved motif, QALGGHMN in the zinc-finger with a short leucine repeat in the LDLELRLGL motif closed to C-terminal. These two conserved motifs share respectively higher identity with those in the floral regulator SUPERMAN gene, indicating that GmN479 may function as a transcriptional regulator, and is a likely candidate for playing a role in nodule-morphogenesis. Blotting data showed that GmN479 is a single copy presenting in the genome of soybean nodule, and its expression profile is similar to that of Lb-a, but it is different from that of ENOD2. GUS staining showed that GmN479 promoter just functions in the infected cells of nodules, indicating that the GmN479 is one of the truly symbiotically induced host genes, and belongs to a late nodulin gene. The expression pattern of GmN479 gene seems to imply that it may be closely related to the development of the nodule. In a sense, it may be a useful marker for identifying the development of the infected cell system in the nodules of soybean.

关键词： nodulin GmN479 promoter soybean nodule transgenic plants

有机金属卤化物钙钛矿CH_(3)NH_(3)PbBr_(3)的各向异性Rashba效应

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原子与分子物理学报 2025年第6期42卷 153-158页

作者：蔡锦鸿余达明周贤中广东工业大学集成电路学院广州510006

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出... 详细信息

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出强烈的各向异性.Rashba带分裂的最大系数可达2.0 eV?,并通过分析能级和电荷密度分布解释了Rashba效应的形成机制.这些研究结果有助于深化对CH_(3)NH_(3)PbBr_(3)性质的理解,同时为其在自旋电子学领域的潜在应用提供了理论基础.

关键词：钙钛矿 CH_3NH_3PbBr_3 密度泛函理论自旋轨道耦合

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Biodegradable Polymers,History Tells Polymer Science's Fortune

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Chinese Journal of Polymer Science 2022年第5期40卷 431-432页

作者： xian-hong Wang Changchun Institute of Applied Chemistry CAS

Origin and Overview Biodegradable polymer,according to the International Union of Pure and Applied Chemistry(IUPAC),is defined as“polymer susceptible to degradation by biological activity,with the degradation accompanied by a lowering of its molar mass”.More specifically,biodegradable polymer should ultimately degrade into CO_(2) and water.

关键词： polymer IUPAC molar

Experimental study on WFeNiMo high-entropy alloy projectile penetrating semi-infinite steel target

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Defence Technology（防务技术） 2022年第8期18卷 1470-1482页

作者： Hai-hua Chen xian-feng Zhang Lan-hong Dai Chuang Liu Wei Xiong meng-ting Tan School of Mechanical Engineering Nanjing University of Science&TechnologyNanjingXiaolingwei 200Jiangsu210094China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing101408China

The appearance of high-entropy alloys (HEAs) makes it possible for a material to possess both high strength and high ductility. It is with great potential to apply HEAs under extreme conditions such as in the penetration process. In this paper, experiments of WFeNiMo HEA and tungsten heavy alloy (WHA) projectiles penetrating medium-carbon steel were conducted by using the ballistic gun and two-stage light-gas gun that can accelerate projectiles to impact velocities ranging from 1162 m/s to 2130 m/s. Depth of penetration (DOP) at elevated impact velocities of HEA and WHA projectiles were obtained firstly. Combined with the macroscopic and microscopic analysis of the residual projectiles, the transition of the penetration mode of the WFeNiMo HEA projectile was identified systemically. The experimental results indicated that the penetration mode of the HEA projectile changes from self-sharpening to mushrooming with the increase of impact velocity, while for the WHA projectile, the penetration mode is always mushrooming. The microstructure of the residual HEA projectiles showed that the phases tangle with each other and the morphology of the microstructure of the phases differs in the two penetration modes. Besides, the evolution of shear bands and fractures varies in the two modes. The evolution of the microstructure of HEAs causes the sharp-pointed nose to disappear and the HEA projectile ultimately becomes blunt as the impact velocity increases.

关键词： WFeNiMo high-entropy alloys Tungsten heavy alloys Penetration mode Self-sharpening penetration Mushrooming deformation