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Fermi/LAT observations of lobe-dominant radio galaxy 3C 207 and possible radiation region of γ-rays

Research in Astronomy and Astrophysics 2018年第6期18卷 93-98页

作者： Sheng-Chu Guo hai-ming zhang Jin zhang En-Wei Liang Guangxi Key Laboratory for Relativistic Astrophysics Department of Physics Guangxi University Key Laboratory of Space Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences

3 C 207 is a lobe-dominant radio galaxy with a one sided jet and bright knots, spanning a kpcMpc scale, which have been resolved in the radio, optical and X-ray bands. This target was confirmed as a γ-ray emitter with Fermi/LAT, but it is uncertain whether the γ-ray emission region is the core or knots due to the low spatial resolution of Fermi/LAT. We present an analysis of its Fermi/LAT data acquired during the past 9 years. Different from the radio and optical emission from the core, it is found that theγ-ray emission is steady without detection of flux variation at over a 2σ confidence level. This likely implies that the γ-ray emission is from its knots. We collect the radio, optical and X-ray data of knot-A,the closest knot from the core at 1.4′′, and compile its spectral energy distribution(SED). Although the single-zone synchrotron+SSC+IC/CMB model that assumes knot-A is at rest can reproduce the SED in the radio-optical-X-ray band, the predicted γ-ray flux is lower than the LAT observations and the derived magnetic field strength deviates from the equipartition condition by 3 orders of magnitude. Assuming that knot-A is moving relativistically, its SED from radio to γ-ray bands would be represented well with the single-zone synchrotron+SSC+IC/CMB model under the equipartition condition. These results likely suggest that the γ-ray emission may be from knot-A via the IC/CMB process and the knot should have relativistical motion. The jet power derived from our model parameters is also roughly consistent with the kinetic power estimated with radio data.

关键词： galaxies: active galaxies: jets radiation mechanisms: non-thermal galaxies: individual(3C 207)

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Analytical model for straight hemming based on minimum energy method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 532-542页

作者： Qian WANG Xiang-huai DONG He-zong LI hai-ming zhang National Engineering Research Center of Die & Mold CAD Shanghai Jiao Tong University Shanghai 200030 China

An analytical model for straight hemming was developed based on minimum energy method to study the effect of flanging die corner radius on hemming *** order to calculate plastic strain and strain energy more exactly,the neutral layer of specimen corner after hemming is assumed to be a half ellipse with its major semi-axis *** hardening rule is adopted to describe bending and reverse bending processes neglecting Bauschinger *** model takes into account the material property parameters in order to satisfy a wide application range of different *** profile,creepage/growing(roll-in/roll-out) and maximum equivalent strain are predicted,which are greatly influenced by the flanging die corner *** facilities were designed and hemming experiments were *** predicted results of the present analytical model were compared to experimental data as well as finite element(FE) simulation *** was confirmed that they are in good agreement,and the model can be used to evaluate whether the material used as an outer panel for hemming is appropriate and to optimize process parameters when the material used for hemming is changed.

关键词： Analytical model Minimum energy method Defects Large deformation Hemming

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Research in Astronomy and Astrophysics 2016年第11期16卷 43-52页

作者： Yong-Kai Zhu Jin zhang hai-ming zhang En-Wei Liang Da-hai Yan Wei Cui Shuang-Nan zhang Guangxi Key Laboratory for Relativistic Astrophysics Department of Physics Guangxi University Nanning 530004 China Key Laboratory of Space Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Physics and Astronomy Purdue University West Lafayette IN 47907 USA

By modeling the broadband spectral energy distributions （SEDs） of a typical flat spectrum radio quasar （FSRQ, 3C 279） and two GeV narrow-line Seyfert 1 galaxies （NLSls, PMN J0948＋0022 and 1H 0323＋342） in different flux stages with one-zone leptonic models, we find a universal correlation between their Doppler factors （δ） and peak luminosities （Lc） of external Compton scattering bumps. Compiling a combined sample of FSRQs and GeV NLSls, it is found that both FSRQs and GeV NLSls in different stages and in different sources follow the same δ-Lc correlation well. This indicates that the variations of observed luminosities may be essentially due to the Doppler boosting effect. The universal δ-Lo relation between FSRQs and GeV NLS 1 s in different stages may be further evidence that the particle acceleration and radiation mechanisms for the two kinds of sources are similar. In addition, by replacing Lc with the observed luminosity in the Fermi/LAT band （LLAT）, this correlation holds and it may serve as an empirical indicator of δ. We estimate the δ values with LLAT for 484 FSRQs in the Fermi/LAT Catalog and they range from 3 to 41, with a median of 16, which are statistically consistent with the values derived by other methods.

关键词： galaxies: active - galaxies: jets - quasars: general - galaxies: Seyfert

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Effects of process parameters on fragment and refinement of millimeter- grade coarse grains for 316LN steel during hot cogging

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Journal of Iron and Steel Research International 2017年第5期24卷 529-535页

作者： Da-shan Sui hai-ming zhang Hong-yang Zhu Zhe Zhu Zhen-shan Cui National Die & Mold CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China Shanghai Heavy Machinery Plant Shanghai 200245 China

The heterogeneous mixed-grain microstructure is a common defect for the heavy forging of 316LN austenitie stainless steel. Isothermal compression experiments were performed on a Gleeble-3500 thermo-mechanical simulator to investigate the effect of process parameters on the fragment and re- finement of millimeter-grade coarse grains （MCGs） during hot cogging. The experimental results in- dicate that the stress of MCG specimens is much larger than that of fine grain （FG） ones at 1150 ℃, while the stress difference between MCG and FG samples became smaller at 1200 ℃. Moreover, the MCGs can be well fragmented and refined under the condition of temperature of 1200 ℃, strain rate of 0.01 s-1 , and reduction rate of 50%. Meanwhile, numerical simulations were conducted to study the influences of temperature, strain and strain rate on microstructure evolution. The results of ex- periments and simulations comprehensively demonstrate that the MCG results in the increase of de- formation resistance and incompatibility of deformation, and it can be fragmented and refined at 1200 ℃ so that the plastic deformation energy decreases remarkably with the increase of temperature from 1 150 to 1200 ℃.

关键词： 316LN steel Hot deformation Coarse grain Microstrueture evolution Numerical simulation

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Is TOL 1326–379 a Prototype ofγ-Ray Emitting FR0 Radio Galaxy?

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Research in Astronomy and Astrophysics 2022年第3期22卷 47-56页

作者： Wen-Jing Fu hai-ming zhang Jin zhang Yun-Feng Liang Su Yao En-Wei Liang Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China School of Physics Beijing Institute of TechnologyBeijing 100081China Max-Planck-Institute für Radioastronomie Auf dem Hügel 69D-53121 BonnGermany

With the possible spacial association to the Fermi/LAT source 3 FGL J 1330.0-3818,TOL 1326-379 may be the first one that is identified as a 7-ray emitting Fanaroff-Riley type 0 radio galaxy(FRO RG).We analyze the~12 yr Fermi/LAT observation data of thisγ-ray source and examine its association to TOL *** show that theγ-ray source(named as J1331.0-3818)is tentatively detected with a TS value of 28.7,3 FGL J 1330.0-3818 is out of the 95%containment of J1331.0-3818,and their positions are spatially separated~0°.2.4 FGL J1331.3-3818 falls into the 68%containment of J1331.0-3818,suggesting that our result agrees with that reported in the Fourth Fermi LAT Source *** 1326-379 is out of the 95%containment of J1331.0-3818,and their positions are spatially separated~0°.4,indicating that the association between J1331.0-3818 and TOL 1326-379 is quite ***,we do not find other possible potential radio or X-ray counterpart within the circle centered at J1331.0-3818 with a radius of 0°.*** spectral energy distribution(SED)of TOL 1326-379 shows a bimodal feature as seen in theγ-ray emitting *** fit the SED with the one-zone leptonic model and find that the average energy spectrum of J1331.0-3818 agrees with the model *** that J1331.0-3818 is an unidentified 7-ray source,we derive the upper-limit of theγ-ray flux for TOL *** is not tight enough to exclude this possibility with the SED *** on these results,we cautiously argue that theγ-ray source J1331.0-3818 is associated with TOL 1326-379 and its jet radiation physic is similar to thoseγ-ray emitting RGs.

关键词： radiation mechanisms:non-thermal galaxies:active galaxies galaxies:radio jets gamma-rays:galaxies

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Investigation of Combining Plant Genotypic Values and Molecular Marker Information for Constructing Core Subsets

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Journal of Integrative Plant Biology 2006年第11期48卷 1371-1378页

作者： Jian-Cheng Wang Jin Hu Ning-Ning Liu hai-ming Xu Sheng zhang Department of Agronomy Zhejiang University Hangzhou 310029 China

In the present study, a strategy was proposed for constructing plant core subsets by clusters based on the combination of continuous data for genotypic values and discrete data for molecular marker InformaUon. A mixed linear model approach was used to predict genotyplc values for eliminating the environment effect. The ＂mixed genetic distance＂ was designed to solve the difficult problem of combining continuous and discrete data to construct a core subset by cluster. Four commonly used genetic distances for continuous data （Euclidean distance, standardized Euclidean distance, city block distance, and Mahalanobls distance） were used to assess the validity of the conUnuous data part of the mixed genetic distance; three commonly used genetic distances for discrete data （cosine distance, correlaUon distance, and Jaccard distance） were used to assess the validity of the discrete data part of the mixed genetic distance, A rice germplasm group with eight quantitative traits and information for 60 molecular markers was used to evaluate the validity of the new strategy. The results suggest that the validity of both parts of the mixed geneUc distance are equal to or higher than the common geneUc distance. The core subset constructed on the basis of a combination of data for genotyplc values and molecular marker information was more representative than that constructed on the basis of data from genotypic values or molecular marker informaUon alone. Moreover, the strategy of using combined data was able to treat dominant marker informaUon and could combine any other continuous data and discrete data together to perform cluster to construct a plant core subset.

关键词： cluster core subset genotypic value mixed linear model molecular marker information

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Flux and spectral variation characteristics of 3C 454.3 at the GeV band

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Research in Astronomy and Astrophysics 2018年第4期18卷 23-42页

作者： hai-ming zhang Jin zhang Rui-Jing Lu Ting-Feng Yi Xiao-Li Huang En-Wei Liang Guangxi Key Laboratory for Relativistic Astrophysics Department of Physics Guangxi University Key Laboratory of Space Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences Department of Physics Yunnan Normal University

We analyze the long-term lightcurve of 3C 454.3 observed with Fermi/LAT and investigate its relation to flux in the radio,optical and X-ray *** fitting the 1-day binned Ge V lightcurve with multiple Gaussian functions（MGF）,we propose that the typical variability timescale in the Ge V band is 1–10 *** Ge V flux variation is accompanied by the spectral variation characterized as fluxtracking,i.e.,＂harder when brighter.＂The Ge V flux is correlated with the optical and X-ray fluxes,and a weak correlation betweenγ-ray flux and radio flux is also ***γ-ray flux is not correlated with the optical linear polarization degree for the global lightcurves,but they show a correlation for the lightcurves before MJD *** power density spectrum of the global lightcurve shows an obvious turnover at^7.7 d,which may indicate a typical variability timescale of 3C 454.3 in theγ-ray *** is also consistent with the derived timescales by fitting the global lightcurve with *** spectral evolution and an increase in the optical linear polarization degree along with the increase inγ-ray flux may indicate that the radiation particles are accelerated and the magnetic field is ordered by the shock processes during the *** addition,the nature of 3C 454.3 may be consistent with a self-organized criticality system,similar to Sagittariusand thus the outbursts could be from plasmoid ejections driven by magnetic *** may further support the idea that the jet radiation regions are magnetized.

关键词： gamma rays galaxies — galaxies jets — quasars individual(3C 454.3)

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Design and fabrication of a new fluorescence enhancement system of silver nanoparticles-decorated aligned silver nanowires

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Rare Metals 2019年第12期38卷 1178-1186页

作者： Jian-Chao Wang Hong-Sheng Luo ming-hai zhang Xi-Hong Zu Jie zhang Yu-Xin Gu Guo-Bin Yi School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of Advanced Coatings Research and Development China National Electric Apparatus Research Institute Co.Ltd.Guangzhou 510300China

A new substrate,aligned Ag nanowires decorated with silver nanoparticle composite structure(AgNWs@AgNPs),was fabricated to investigate metalenhanced fluorescence(MEF) and its *** new composite structure was fabricated via a three-phase interface assembly method followed by SnCl2 sensitization and AgNO3 reduction *** size and distribution of the nanoparticles on silver nanowires increased with the sensitization and reduction *** formation of AgNPs on the surfaces of AgNWs was confirmed by multiple characterization methods including scanning electron microscopy(SEM),transmission electron microscope(TEM),atomic force microscopy(AFM) and X-ray diffraction(XRD).The results show that the fluorescence intensity of the poly(3-hexylthiophene)(P3HT) on the composite structure was greatly enhanced compared with that on bare glass substrate,and the intensity increased with the increase in particle sizes and *** mechanism was basedo n the increase in excitation rate and the radiation decay *** new type of substrate could serve as a good and efficient MEF substrate for high-performance fluorescence-based devices.

关键词： Fluorescence enhancement Aligned Ag nanowires Self-assembly Mechanism

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Mechanism on Moho offset induced by aseismic slip of deeply buried faults

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Earthquake Science 2014年第3期27卷 247-256页

作者： Zhen Fu hai-ming zhang Shu-wen Dong Chinese Academy of Geological Sciences School of Earth and Space Sciences Peking University

Recent high-resolution deep seismic reflection profile across the Kunlun fault in northeastern Tibet shows clearly that the Moho is cut off by a complex thrust fault system. Moho offset is a general phenomenon, but little is known about the dynamic mechanism. In this study, contact models with Maxwell materials are used to simulate the mechanical process of Moho offset induced by the aseismic slip of deeply buried faults. Based on the seismic reflection data, we project a single fault model and a complex fault system model with two faults inter- secting. The deformations of the Moho, the aseismic slips, and contact stresses on faults in different models are discussed in detail. Results show that the Moho offset might be produced by aseismic slip of deeply buried faults, and the magnitude is influenced by the friction coefficient of faults and the viscosity of the lower crust. The maximum slip occurs near the Moho on the single fault or at the crossing point of two intersecting faults system. Stress concentrates mainly on the Moho, the deep end of faults, or the crossing point. This study will throw light on understanding the mechanism of Moho offset and aseismic slip of deeply buried faults. The results of complex fault system with two faults intersecting are also useful to understand the shallow intersecting faults that may cause earthquakes.

关键词： Moho offset Aseismic slip - Deeply buriedfaults Numerical simulation Viscoelastic contact model

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Highly variable γ-ray emission of CTD 135 and implications for its compact symmetric structure

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Research in Astronomy and Astrophysics 2021年第8期21卷 173-180页

作者： Ying-Ying Gan hai-ming zhang Jin zhang Xing Yang Ting-Feng Yi Yun-Feng Liang En-Wei Liang Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China School of Physics Beijing Institute of TechnologyBeijing 100081China Department of Physics Yunnan Normal UniversityKunming 650500China

Theγ-ray emission properties of CTD 135,a typical compact symmetric object(CSO),are investigated with-11-year Fermi/LAT *** show that it has bright and significantly variable GeV emission,with theγ-ray luminosity of L_(γ)-10^(47) erg s^(-1) and a variation index of TS_(var)=1002.A quasi-periodic oscillation(QPO)with a periodicity of-460 days is detected in the global 95%false-alarm ***γ-ray emission features are similar to that of *** broadband spectral energy distribution(SED)can be attributed to the radiations of the relativistic electrons accelerated in the core region and the extended *** SED modeling shows that theγ-rays are from the core region,which has a Doppler boosting factor ofδ-10.8 and relativistically moves with a small viewing angle,being similar to blazar *** the base of the analysis results,we propose that the episodic activity of the central engine in CTD135 results in a blazar-like jet and the bubble-like lobes as the Fermi bubbles in the *** strong 7-ray emission with obvious variability is from the jet radiations and the symmetric radio structure is attributed to the *** jet radiation power and disk luminosity in units of Eddington luminosity of CTD 135 follow the same relation as other young radio sources,indicating that its jet radiation may also be driven by the Eddington ratio.

关键词： galaxies:active galaxies:jets radio continuum:galaxies gamma rays:galaxies

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