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Chinese Physics B 2017年第1期26卷 498-502页

作者： Xiang li De-gang Zhao De-Sheng Jiang Jing yang ping Chen Zong-Shun liu Jian-Jun Zhu wei liu Xiao-Guang He Xiao-Jing li Feng liang Jian-ping liu li-qun Zhang Hui yang Yuan-Tao Zhang Guo-Tong Du Heng Long Mo li State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China University of Chinese Academy of Sciences Beijing 100049 China suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences Suzhou 215125 China State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130023 China Microsystem & Terahertz Research Center Chinese Academy of Engineering Physics Chengdu 610200 China

Four blue-violet light emitting Ingan/gan multiple quantum well（MQW） structures with different well widths are grown by metal–organic chemical vapor deposition. The carrier localization effect in these samples is investigated mainly by temperature-dependent photoluminescence measurements. It is found that the localization effect is enhanced as the well width increases from 1.8 nm to 3.6 nm in our experiments. The temperature induced PL peak blueshift and linewidth variation increase with increasing well width, implying that a greater amplitude of potential fluctuation as well as more localization states exist in wider wells. In addition, it is noted that the broadening of the PL spectra always occurs mainly on the low-energy side of the PL spectra due to the temperature-induced band-gap shrinkage, while in the case of the widest well, a large extension of the spectral curve also occurs in the high energy sides due to the existence of more shallow localized centers.

关键词： Ingan/gan multiple quantum wells localization effect well thickness

Extracting spectroscopic factors from elastic transfer reactions

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Science China(Physics,Mechanics & Astronomy) 2019年第3期62卷 108-110页

作者： Zhi Hong li Yun Ju li Jun su Sheng Quan Yan you Bao Wang Bing Guo Ding Nan Er Tao li lin gan wei ping liu China Institute of Atomic Energy College of Physics and Energy Shenzhen University

Spectroscopic factor elucidates the overlap between the initial and final states as well as the occupancy of a given singleparticle *** plays an important role in nuclear reactions and nuclear ***-nucleon transfer reactions such as(J,p)and(d,n)have been used extensively to extract the spectroscopic information of the single-nucleon orbits in nuclei located at or near the stability line[1-3],by comparing the experimental and theoretical differential cross sections as expressed by eq.(1).The uncertainties of the extracted spectroscopic factors are from the statistics of the measurements(3%),the uncertainties of the target thickness(5%),the optical potential parameters for both entrance(15%)and exit channels(15%),the geometrical parameters for the bound states(20%),as well as the spectroscopic factor in d(15%).

关键词： Extracting spectroscopic factors elastic transfer reactions

Hard X-ray Imager (HXI) onboard the ASO-S mission

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Research in Astronomy and Astrophysics 2019年第11期19卷 49-62页

作者： Zhe Zhang Deng-Yi Chen Jian Wu Jin Chang Yi-Ming Hu yang su Yan Zhang Jian-ping Wang Yao-Ming liang Tao Ma Jian-Hua Guo Ming-Sheng Cai Yong-Qiang Zhang Yong-Yi Huang Xiao-Yan Peng Zong-Bin Tang Xuan Zhao Hong-He Zhou lian-Guo Wang Jing-Xing Song Miao Ma Guang-Zhou Xu Jian-Feng yang Di Lu Ying-Hong He Jin-you Tao Xiao-Long Ma Bao-gang Lv Yan-ping Bai Cai-Xia Cao Yu Huang wei-qun gan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201203China National Space Science Center Chinese Academy of SciencesBeijing 100190China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China

Hard X-ray Imager(HXI)is one of the three scientific instruments onboard the Advanced Spacebased Solar Observatory(ASO-S)mission,which is proposed for the 25th solar maximum by the Chinese solar *** is designed to investigate the non-thermal high-energy electrons accelerated in solar flares by providing images of solar flaring regions in the energy range from 30 keV to 200 *** imaging principle of HXI is based on spatially modulated Fourier synthesis and utilizes about 91 sets of bi-grid sub-collimators and corresponding LaBr3 detectors to obtain Fourier components with a spatial resolution of about 3 arcsec and a time resolution better than 0.5 *** engineering prototype has been developed and tested to verify the feasibility of *** this paper,we present background,instrument design and the development and test status of the prototype.

关键词： instrumentation:detectors space vehicles:instruments sun:X-ray techniques:imaging spectroscopy

Evaluation of polarization field in Ingan/gan multiple quantum well structures by using electroluminescence spectra shift

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Chinese Physics B 2020年第3期29卷 221-224页

作者： ping Chen De-gang Zhao De-Sheng Jiang Jing yang Jian-Jun Zhu Zong-Shun liu wei liu Feng liang Shuang-Tao liu Yao Xing li-qun Zhang State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences(CAS)Beijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Nano-devices and Applications of CAS Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China

In order to investigate the inherent polarization intensity in Ingan/gan multiple quantum well(MQW) structures,the electroluminescence(EL) spectra of three samples with different gan barrier thicknesses of 21.3 nm, 11.4 nm, and 6.5 nm are experimentally studied. All of the EL spectra present a similar blue-shift under the low-level current injection,and then turns to a red-shift tendency when the current increases to a specific value, which is defined as the turning *** value of this turning point differs from one another for the three Ingan/gan MQW samples. Sample A, which has the gan barrier thickness of 21.3 nm, shows the highest current injection level at the turning point as well as the largest value of blue-shift. It indicates that sample A has the maximum intensity of the polarization field. The red-shift of the EL spectra results from the vertical electron leakage in Ingan/gan MQWs and the corresponding self-heating effect under the high-level current injection. As a result, it is an effective approach to evaluate the polarization field in the Ingan/gan MQW structures by using the injection current level at the turning point and the blue-shift of the EL spectra profiles.

关键词： Ingan/gan multiple quantum well(MQW) polarization field electroluminescence spectra shift electron leakage current

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RHESSI耀斑中非热电子低能截止的研究

天文学报 2008年第4期49卷 403-412页

作者：韩钢李友平甘为群中国科学院紫金山天文台南京210008

太阳耀斑中硬X射线(HXR)光子谱的低能变平过去一般认为是由于耀斑中非热电子的低能截止造成的,但现在也有作者认为耀斑光子与下层大气的逆康普顿散射(albedo效应)或者其他作用也能够使得HXR光子谱出现低能变平的情形.采用gan et al.(200... 详细信息

太阳耀斑中硬X射线(HXR)光子谱的低能变平过去一般认为是由于耀斑中非热电子的低能截止造成的,但现在也有作者认为耀斑光子与下层大气的逆康普顿散射(albedo效应)或者其他作用也能够使得HXR光子谱出现低能变平的情形.采用gan et al.(2001,2002)中提出的求非热电子低能截止的方法,统计分析了Ramaty High Energy Solar Spectroscopy Imager(RHESSI)卫星在2002—2005年间观测的100个耀斑,发现经albedo校正,有18个耀斑的HXR光子谱可以利用单幂律谱来拟合,在80个可以用双幂律谱来拟合HXR光子谱的耀斑中,有21个耀斑可以直接用单幂律电子谱加一个低能截止来解释.低能截止范围为20—50keV,平均值约为30keV.同时也分析了耀斑光子谱特征的其他可能解释.

关键词：太阳耀斑,X-射线,伽玛射线

Influence of carrier gas H2 flow rate on quality of p-type gan epilayer grown and annealed at lower temperatures

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Chinese Physics B 2018年第12期27卷 499-503页

作者： Shuang-Tao liu Jing yang De-gang Zhao De-Sheng Jiang Feng liang ping Chen Jian-Jun Zhu Zong-Shun liu wei liu Yao Xing li-Yuan Peng li-qun Zhang Wen-Jie Wang Mo li State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China suzhou Institute of Nanotech and Nanobionics Chinese Academy of SciencesSuzhou 215123China Microsystem&Terahertz Research Center Chinese Academy of Engineering PhysicsChengdu 610200China

In this work, we study the influence of carrier gas H2flow rate on the quality of p-type gan grown and annealed at lower temperatures. It is found that the concentration of H atoms in Mg-doped gan epilayer can effectively decrease with appropriately reducing the carrier gas H2flow rate, and a high-quality p-type gan layer could be obtained at a comparatively low annealing temperature by reducing the carrier gas H2flow rate. Meanwhile, it is found that the intensity and wavelength of DAP peak are changed as the annealing temperature varies, which shows that the thermal annealing has a remarkable effect not only on the activation of acceptors but also on the compensation donors.

关键词： p-type gan thermal annealing H atom state

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耀斑日冕硬X射线源观测研究

天文学报 2011年第6期52卷 481-494页

作者：白伟东李友平甘为群中国科学院紫金山天文台南京210008 中国科学院暗物质与空间天文重点实验室南京210008 中国科学院研究生院北京100049

对于足点被日面边缘遮挡住的耀斑的观测研究是诊断日冕硬X射线辐射的一个重要方法.通过统计分析RHESSI(Reuven Ramaty High-Energy Solar SpectroscopicImager)卫星观测到的71个此类耀斑硬X射线源发现,前人提出的两类源,即日冕X射线辐... 详细信息

对于足点被日面边缘遮挡住的耀斑的观测研究是诊断日冕硬X射线辐射的一个重要方法.通过统计分析RHESSI(Reuven Ramaty High-Energy Solar SpectroscopicImager)卫星观测到的71个此类耀斑硬X射线源发现,前人提出的两类源,即日冕X射线辐射中热辐射与非热辐射源区空间分离较小的源和分离较大的源,在能谱、成像、光变曲线以及GOES持续时间等方面都没有显著的区别,其中辐射区的面积、耀斑总热能以及GOES持续时间与分离距离之间有很好的相关性.这些结果支持近年来提出的一些耀斑统一模型.同时也表明Masuda耀斑只是一类非常特殊的事件,不具有日冕硬X射线辐射的一般特征.

关键词：太阳耀斑太阳日冕太阳 X射线

linked color imaging vs Lugol chromoendoscopy for esophageal squamous cell cancer and precancerous lesion screening: A noninferiority study

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World Journal of Gastroenterology 2023年第12期29卷 1899-1910页

作者： Zi-Xin Wang Long-Song li Song su Jin-ping li Bo Zhang Nan-Jun Wang Sheng-Zhen liu Sha-Sha Wang Shuai Zhang Ya-wei Bi Fei Gao qun Shao Ning Xu Bo-Zong Shao Yi Yao Fang liu En-Qiang linghu Ning-li Chai Department of Gastroenterology The First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND Lugol chromoendoscopy(LCE)has served as a standard screening technique in high-risk patients with esophageal ***,LCE is not suitable for general population screening given its side *** color imaging(LCI)is a novel image-enhanced endoscopic technique that can distinguish subtle differences in mucosal *** To compare the diagnostic performance of LCI with LCE in detecting esophageal squamous cell cancer and precancerous lesions and to evaluate whether LCE can be replaced by LCI in detecting esophageal neoplastic *** In this prospective study,we enrolled 543 patients who underwent white light imaging(Wli),LCI and LCE *** compared the sensitivity and specificity of LCI and LCE in the detection of esophageal neoplastic *** features and color analysis of lesions were *** In total,43 patients(45 neoplastic lesions)were *** them,36 patients(38 neoplastic lesions)were diagnosed with LCI,and 39 patients(41 neoplastic lesions)were diagnosed with *** sensitivity of LCI was similar to that of LCE(83.7%vs 90.7%,P=0.520),whereas the specificity of LCI was greater than that of LCE(92.4%vs 87.0%,P=0.007).The LCI procedure time in the esophageal examination was significantly shorter than that of LCE[42(34,50)s vs 160(130,189)s,Psurrounding mucosa in LCI was significantly greater than that observed with ***,the color difference in LCI was similar in different pathological types of esophageal squamous cell *** LCI offers greater specificity than LCE in the detection of esophageal squamous cell cancer and precancerous lesions,and LCI represents a promising screening strategy for general populations.

关键词： linked color imaging Lugol chromoendoscopy Esophageal squamous cell cancer Precancerous lesions Color difference

The Lyman-alpha Solar Telescope (LST) for the ASO-S mission——Ⅰ. Scientific objectives and overview

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Research in Astronomy and Astrophysics 2019年第11期19卷 23-32页

作者： Hui li Bo Chen li Feng Ying li Yu Huang Jing-wei li Lei Lu Jian-Chao Xue Bei-li Ying Jie Zhao Yu-Tong yang wei-qun gan Cheng Fang Ke-Fei Song Hong Wang Quan-Feng Guo ling-ping He Bo Zhu Cheng Zhu Lei Deng Hai-Chao Bao Cai-Xia Cao Zhong-Guang yang Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Changchun Institute of Optics FineMechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201210China

As one of the payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is aimed at imaging the sun and the inner corona up to 2.5 R⊙(mean solar radius)in both the Lyα(121.6 nm)and visible wavebands with high temporo-spatial resolution,mainly targeting solar flares,coronal mass ejections(CMEs)and filaments/*** observations allow us to trace solar eruptive phenomena from the disk center to the inner corona,to study the relationships between eruptive prominences/filaments,solar flares and CMEs,to explore the dynamical processes and evolution of solar eruptions,to diagnose solar winds,and to derive physical parameters of the solar *** is actually an instrument suite,which consists of a Solar Disk Imager(SDI),a Solar Corona Imager(SCI),a White-light Solar Telescope(WST)and two Guide Telescopes(GTs).This is the first paper in a series of LST-related *** this paper,we introduce the scientific objectives,present an overview of the LST payload and describe the planned *** detailed design and data along with potential diagnostics are described in the second(Paper II)and third(Paper III)papers,respectively,appearing in this issue.

关键词： sun flares-sun coronal mass ejections(CMEs)-sun filaments,prominences-sun corona-sun chromosphere-sun UV radiation

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SMP2仿真引擎的多核并行化

宇航学报 2010年第7期31卷 1883-1891页

作者：苏年乐周鸿伟李群王维平国防科技大学信息系统与管理学院长沙410073 北京跟踪与通信技术研究所北京100094

仿真模型可移植性规范2(SMP2)是由欧洲航天局制定并得到广泛应用的仿真模型开发与集成规范。SMP2仿真引擎目前只支持串行仿真,并行化可提高其在多核平台上的运行速度。研究了并行SMP2仿真引擎的体系结构、运行过程及运行状态,采用C++和O... 详细信息

仿真模型可移植性规范2(SMP2)是由欧洲航天局制定并得到广泛应用的仿真模型开发与集成规范。SMP2仿真引擎目前只支持串行仿真,并行化可提高其在多核平台上的运行速度。研究了并行SMP2仿真引擎的体系结构、运行过程及运行状态,采用C++和OpenMP设计并实现了基于乐观时间同步协议的并行SMP2仿真引擎。最后开发了卫星导航系统全球格网精度因子分析的实例,在双路四核计算机上获得了5.8倍-6.3倍的加速比。

关键词：仿真模型可移植性规范仿真引擎并行离散事件仿真多核多线程