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Multi-wavelength emission from 3C 66A: clues to its redshift and gamma-ray emission location

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Research in Astronomy and Astrophysics 2013年第4期13卷 411-419页

作者： Da-hai Yan zhong-Hui Fan Yao Zhou Ben-zhong Dai Department of Physics Yunnan University

The quasi-simultaneous multi-wavelength emission of TeV blazar 3C 66A is studied by using a one-zone multi-component leptonic jet model. It is found that the quasi-simultaneous spectral energy distribution of 3C 66A can be well reproduced; in particular, the first three months of its average Fermi-LAT spectrum can be well reproduced by the synchrotron self-Compton component plus external Compton component of the broad line region （BLR）. Clues to its redshift and gamma-ray emission location are obtained. The results indicate the following. （i） On the redshift： The theoretical intrinsic TeV spectra can be predicted by extrapolating the reproduced GeV spectra. Through comparing these extrapolated TeV spectra with the corrected observed TeV spectra from extragalactic background light, it is suggested that the redshift of 3C 66A could be between 0.1 and 0.3, with the most likely value being ~ 0.2. （ii） On the gamma-ray emission location： To well reproduce the GeV emission of 3C 66A under different assumptions on the BLR, the gamma-ray emission region is always required to be beyond the inner zone of the BLR. The BLR absorption effect on gamma-ray emission confirms this point.

关键词： BL Lacertae objects: individual (3C 66A) - galaxies: active - gamma-rays: theory - radiation mechanisms: non-thermal

Development of Continuous Coating and Plating Strip Steel

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Journal of Iron and Steel Research International 2001年第2期8卷 34-41页

作者： ZHANG Qi-fu HUANG Jian-zhong ZHAO Pei zhong hai-feng Central Iron & Steel Research Institute

The development trend of coated and plated technology for continuous strip steels,which include hot dip plating,electroplating,organic coating and vacuum plating technology,were summarized.

关键词： strip steel coating technology plating technology development

Temperature and solar radiation utilization of rice for yield formation with different mechanized planting methods in the lower reaches of the Yangtze River,China

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Journal of Integrative Agriculture 2017年第9期16卷 1923-1935页

作者： XING Zhi-peng WU Pei ZHU Ming QIAN hai-jun HU Ya-jie GUO Bao-wei WEI hai-yan XU Ke huo zhong-yang DAI Qi-gen ZHANG Hong-cheng Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Co-Innovation Center for Modem Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009P.R.China

Several studies have demonstrated the effect of planting methods on rice yield, but information on the climate resources is limited. This study aims to reveal the effects of planting methods on climate resources associated with rice yield in a rice-wheat rotation system in the lower reaches of the Yangtze River, China. Field experiments were conducted in 2014 and 2015 with two japonica, two indica hybrid, and two japonica-indica hybrid varieties grown under three mechanized planting methods： carpet seedling of mechanical transplanting（CT）, mechanical direct seeding（DS）, and pot-hole seedling of mechanical transplanting（PT）. The rice yield and total dry matter under PT were greater than those under CT and DS methods. Besides, the entire growth duration and daily production showed significant positive relations with rice yield. Compared with CT and DS, the effective accumulated temperature and cumulative solar radiation of rice under PT were higher in phenological phases. In addition, the dry matter/effective accumulated temperature and solar energy utilization of rice under CT and DS were higher during vegetative phase and lower during reproductive and grain filling phases in contrast to PT. The mean daily temperature and mean daily solar radiation in the entire growth duration showed significant positive correlation with rice yield, total dry matter, and harvest index. This study demonstrated that when the mean daily temperature is 〈25.1°C in vegetative phase and 〉20.1°C in grain filling phase, rice yield could be increased by selecting mechanized planting methods. Most varieties under PT method exhibited high yield and climate resources use efficiency compared with CT and DS. In conclusion, the PT method could be a better cultivation measure for high rice yield, accompanied with high temperature and solar radiation use efficiency in a rice-wheat rotation system in the lower reaches of the Yangtze River, China.

关键词： rice mechanized planting methods temperature solar radiation

A Hybrid FETD-FDTD Method with Nonconforming Meshes

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Communications in Computational Physics 2011年第3期9卷 828-842页

作者： Bao Zhu Jiefu Chen Wanxie zhong Qing huo Liu State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116023P.R.China Department of Electrical and Computer Engineering Duke UniversityDurham NC 27708USA

A quasi non-overlapping hybrid scheme that combines the finite-difference time-domain(FDTD)method and the finite-element time-domain(FETD)method with nonconforming meshes is developed for time-domain solutions of Maxwell’s *** FETD method uses mixed-order basis functions for electric and magnetic fields,while the FDTD method uses the traditional Yee’s grid;the two methods are joined by a buffer zone with the FETD method and the discontinuous Galerkin method is used for the domain decomposition in the FETD *** main features of this technique is that it allows non-conforming meshes and an arbitrary numbers of FETD and FDTD *** hybrid method is completely stable for the time steps up to the stability limit for the FDTD method and FETD *** results demonstrate the validity of this technique.

关键词： Finite-element time-domain finite-difference time-domain discontinuous Galerkin domain decomposition non-conforming mesh

Cu掺杂及缺陷共存对ZnO光催化影响的理论研究

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原子与分子物理学报 2025年第2期42卷 24-32页

作者：张海峰赵晋忠伊思静卢士香山西农业大学基础部太谷030801 北京理工大学化学与化工学院北京100081

采用密度泛函理论研究了Cu掺杂及缺陷共存对ZnO光催化性能的影响.计算时考虑了富O和贫O两种掺杂条件.研究结果表明富O条件有利于Cu的掺杂,贫O条件则产生抑制作用.当Cu掺杂浓度较低时,不论在何种掺杂条件下,Cu的主要掺杂方式均为Cu_(Zn)... 详细信息

采用密度泛函理论研究了Cu掺杂及缺陷共存对ZnO光催化性能的影响.计算时考虑了富O和贫O两种掺杂条件.研究结果表明富O条件有利于Cu的掺杂,贫O条件则产生抑制作用.当Cu掺杂浓度较低时,不论在何种掺杂条件下,Cu的主要掺杂方式均为Cu_(Zn)型.当Cu掺杂浓度较高时,富O条件下以Cu_(Zn)-Cu_(Zn)型掺杂方式为主,贫O条件下Cu_(Zn)-Cu_(Zn)和Cu_(Zn)-Cui这两种掺杂方式都有可能出现.富O条件下Cu掺杂会促进V_(Zn)和O_(i)缺陷的产生,且引入的V_(Zn)和O_(i)缺陷趋向于距离Cu原子最近.Cu掺杂可有效降低ZnO的带隙宽度,且随着掺杂浓度的增加,相应模型的带隙宽度会继续降低.V_(Zn)、O_(i)和V_(O)缺陷共存使相应模型的带隙宽度有所增加.Cu掺杂及V_(Zn)、O_(i)、V_(O)缺陷共存使模型对可见光发生响应,扩展了模型对太阳光的吸收范围.对于Cu掺杂模型,富O条件下Cu_(Zn)-Cu_(Zn)是有利的光催化模型.对于缺陷共存模型,富O条件下Cu_(Zn)-Cu_(Zn)-V_(Zn)是有利的光催化模型,其次是Cu_(Zn)-V_(Zn)和Cu_(Zn)-O_(i),贫O条件下Cu_(Zn)-V_(O)是有利的光催化模型.

关键词： ZnO Cu掺杂缺陷共存密度泛函理论光催化

A fast ellipsoid model for asteroids inverted from lightcurves

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Research in Astronomy and Astrophysics 2013年第4期13卷 471-478页

作者： Xiao-Ping Lu hai-Bin Zhao zhong You Faculty of Information Technology Macao University of Science and Technology Purple Mountain Observatory Chinese Academy of Sciences

Research about asteroids has recently attracted more and more attention, especially focusing on their physical structures, such as their spin axis, rotation period and shape. The long distance between observers on Earth and asteroids makes it impossible to directly calculate the shape and other parameters of asteroids, with the exception of Near Earth Asteroids and others that have passed by some spacecrafts. Photometric measurements are still generally the main way to obtain research data on asteroids, i.e. the lightcurves recording the brightness and positions of asteroids. Supposing that the shape of the asteroid is a triaxial ellipsoid with a stable spin, a new method is presented in this article to reconstruct the shape models of asteroids from the lightcurves, together with other physical parameters. By applying a special curvature function, the method calculates the brightness integration on a unit sphere and Lebedev quadrature is employed for the discretization. Finally, the method searches for the optimal solution by the Levenberg-Marquardt algorithm to minimize the residual of the brightness. By adopting this method, not only can related physical parameters of asteroids be obtained at a reasonable accuracy, but also a simple shape model of an ellipsoid can be generated for reconstructing a more sophisticated shape model.

关键词： ellipsoid model - lightcurves - photometric - shape: asteroids

Low-leakage diode-triggered silicon controlled rectifier for electrostatic discharge protection in 0.18-μm CMOS process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第7期10卷 1060-1066页

作者： Xiao-yang DU Shu-rong DONG Yan HAN Ming-xu huo Da-hai HUANG ESD Lab Department of Information Science & Electronic Engineering Zhejiang University Hangzhou 310027 China

A diode-triggered silicon controlled rectifier (DTSCR) is being developed as an electrostatic discharge (ESD) pro- tection device for low voltage applications. However, DTSCR leaks high current during normal operation due to the Darlington effect of the triggering-assist diode string. In this study, two types of diode string triggered SCRs are designed for low leakage consideration; the modified diode string and composite polysilicon diode string triggered SCRs (MDTSCR & PDTSCR). Com- pared with the conventional DTSCR (CDTSCR), the MDTSCR has a much lower substrate leakage current with a relatively large silicon cost, and the PDTSCR has a much lower substrate leakage current with similar area and shows good leakage performance at a high temperature. Other DTSCR ESD properties are also investigated, especially regarding their layout, triggering voltage and failure current.

关键词： Electrostatic discharge (ESD) protection Diode-triggered silicon controlled rectifier (DTSCR) Leakage current

2D sandwich-like nanosheets of ultrafine Sb nanoparticles anchored to graphene for high-efficiency sodium storage

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Nano Research 2017年第12期10卷 4360-4367页

作者： Xiaowu Liu Man Gao hai Yang Xiongwu zhong Yan Yu CAS Key Materiels for Energy Conversion Department of Materials Science and Engineering University of Science and Technology of Chine Hefei 230026 China Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University Tianjin 300071 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China

Sb is considered a promising anode material for high-performance sodium-ion batteries （NIBs） owing to its high theoretical specific capacity （660 mAh-g-1）. However, Sb shows a very large volume change （-200%） during sodiation and desodiation, leading to poor electrochemical performance. Here, we designed and tested a sandwich-like graphene-supported Sb nanocomposite （denoted Sb@RGO@Sb）, in which ultrafine Sb nanoparticles are uniformly anchored on a reduced graphene oxide （RGO） surface. The ultrafine Sb nanocrystals anchored on the RGO surface minimize the aggregation of Sb and inhibit restacking of the RGO sheets, leading to a minimum transport length for both ions and electrons. The graphene layer not only accommodates the large volume variation of Sb during cycling but also promotes the electron conductivity of the whole electrode. Owing to its unique structure, this sandwich-like composite exhibits superior sodium storage properties.

关键词： Sb/graphene composites sodium ion battery anode sandwich-like structure

State and parameter identification of linearized water wave equation via adjoint method

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Science China(Information Sciences) 2024年第10期67卷 283-297页

作者： Yang YU Cheng-zhong XU hai-Long PEI Jinpeng YU School of Automation Qingdao University LAGEP Batiment CPE University Claude Bernard-Lyon 1 School of Automation Science and Engineering Key Laboratory of Autonomous Systems and Networked ControlMinistry of Education Guangdong Engineering Technology Research Center of Unmanned Aerial Vehicle SystemSouth China University of Technology

In this paper, we focus on the state and parameter identification problem of a hydrodynamical system. This system is modeled as a linearized water wave equation(LWWE), a hyperbolic state-space model coupled with a Laplace equation. We assume that the wave elevation at two distinct points is the only measurement of water waves. We show that the state and water depth can be reconstructed from this point measurement records. The identification problem is recast as an optimization problem over an infinite-dimensional space. We propose the adjoint method-based identification algorithm to generate an estimated state and water depth. We then performed a numerical simulation to show the effectiveness of our designed algorithm by comparing it with existing studies.

关键词： linearized water wave equation (LWWE) point observation state estimation parameter identification adjoint method numerical simulation