检索结果-南通市图书馆

活动区物质运动、电流演化与耀斑爆发的物理关系

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

天文学报 1992年第1期33卷 25-35页

作者：许敖敖张和棋南京大学天文系南京210008 中国科学院紫金山天文台南京210008

本文基于:(i)日珥(暗条)以及部分EUV环,x-ray环可能构成活动区中主要电流回路;(ii)活动区磁场由活动区电流系所激发的场和所谓背景磁场组成;(iii)活动区磁场和电流的演化与活动区光球物质运动密切相关。采用Kuperus-Raadu型电流回路,并... 详细信息

本文基于:(i)日珥(暗条)以及部分EUV环,x-ray环可能构成活动区中主要电流回路;(ii)活动区磁场由活动区电流系所激发的场和所谓背景磁场组成;(iii)活动区磁场和电流的演化与活动区光球物质运动密切相关。采用Kuperus-Raadu型电流回路,并根据由观测确定的活动区光球物质运动的几种主要形式,通过数值方法,求解电流的运动方程和能量方程,获得了活动区电流演化的动态规律。所得结果从理论上阐明了耀斑的发生及其基本物理过程,与活动区物质运动及电流演化之间的内禀关系。

关键词：活动区物质运动电流演化耀斑

在线全文

学校读者我要写书评

暂无评论

人造卫星观测中重叠像的分离

天文学报 2008年第3期49卷 321-326页

作者：平一鼎中国科学院紫金山天文台南京210008

在人造卫星观测中,由于观测目标相对背景恒星的运动,观测目标成点状像而背景恒星的像则被拉长.该现象极易造成观测目标与背景恒星发生重叠.从而给卫星跟踪观测或是进行同步目标探测造成困难.本文利用图像处理的方法对重叠的目标像和恒... 详细信息

在人造卫星观测中,由于观测目标相对背景恒星的运动,观测目标成点状像而背景恒星的像则被拉长.该现象极易造成观测目标与背景恒星发生重叠.从而给卫星跟踪观测或是进行同步目标探测造成困难.本文利用图像处理的方法对重叠的目标像和恒星像进行分离,取得了较为理想的效果.

关键词：航天器,技术图像处理

在线全文

学校读者我要写书评

暂无评论

关于太阳白光耀斑连续发射起源的讨论

天文学报 1997年第4期38卷 394-396页

作者：甘为群中国科学院紫金山天文台南京210008

At present there are three kinds of explanations of the origin of solar white-lightflares. One view holds that the chromospheric condensation is responsible for thecontinuous emission of white-light flares, either belonging to type Ⅰ or type ⅡAnother interpretation snys that the non-thermal effects may increase the opacity ofthe upper photosphere and consequently the deeper layers can be heated *** still other view is that the strong chromospheric heating can radatively heat thetemperature minimum region and the upper photosphere. We examine each of thesemechanisms and point out that none of them may be considered to be quitesatisfactory in interpreting the continua of white-light flares. Then a possible outlet istentatively proposed, which may take into account both chromospheric condensationand non-thermal effects. A semiempirical model will be requlred to justify thissuggestion.

关键词：太阳白光耀斑耀斑连续发射起源机制

在线全文

学校读者我要写书评

暂无评论

中国古历定朔推步综述

天文学进展 1996年第1期14卷 66-76页

作者：李勇张培瑜南京大学天文系南京210008 中国科学院紫金山天文台南京210008

“朔”简言之表日月黄经相等，先民对其认识经历了一个从平朔到定朔的过程。通过研读古历，文中分析并归纳了不同时期中国古历日制度的基本元素之一──朔的两种推步方法：“积年法”和“《授时历》法”，其中包括平朔、日躔、月离、及... 详细信息

“朔”简言之表日月黄经相等，先民对其认识经历了一个从平朔到定朔的过程。通过研读古历，文中分析并归纳了不同时期中国古历日制度的基本元素之一──朔的两种推步方法：“积年法”和“《授时历》法”，其中包括平朔、日躔、月离、及定朔的推步方法等；得出了由各历的基本历数直接推出的中国古历定朔计算的一般公式；同时亦给出了《授时历》的推朔法和部分算例。

关键词：天文学史古历定朔推步法

Two-dimensional materials for future information technology: status and prospects

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2024年第6期67卷 1-147页

作者： Hao QIU Zhihao yu Tiange ZHAO Qi ZHANG Mingsheng XU Peifeng LI Taotao LI Wenzhong BAO Yang CHAI Shula CHEN Yiqi CHEN Hui-Ming CHENG Daoxin DAI Zengfeng DI Zhuo DONG Xidong DUAN yuhan FENG yu FU Jingshu GUO Pengwen GUO yue HAO Jun HE Xiao HE Jingyi HU Weida HU Zehua HU Xinyue HUANG Ziyang HUANG Ali IMRAN Ziqiang KONG Jia LI Qian LI Weisheng LI Lei LIAO Bilu LIU Can LIU Chunsen LIU Guanyu LIU Kaihui LIU Liwei LIU Sheng LIU yuan LIU Donglin LU Likuan MA Feng MIAO Zhenhua NI Jing NING Anlian PAN Tian-Ling REN Haowen SHU Litao SUN yue SUN Quanyang TAO Zi-Ao TIAN Dong wang Hao wang Haomin wang Jialong wang Junyong wang Wenhui wang Xingjun wang Yeliang wang yuwei wang Zhenyu wang Yao WE... School of Electronic Science and Engineering Nanjing University School of Integrated Circuits Interdisciplinary Research Center for Future Intelligent Chips (Chip-X)Nanjing University School of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications State Key Laboratory of Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences School of Physics and Key Lab of Quantum Materials and devices of the Ministry of Education School of Electronic Science & EngineeringSoutheast University College of Integrated Circuits State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University Suzhou Laboratory State Key Laboratory of Integrated Chips and Systems School of MicroelectronicsFudan University Shaoxin Laboratory department of Applied Physics The Hong Kong Polytechnic University Key Laboratory for Micro-Nano Physics and Technology of Hunan Province College of Materials Science and EngineeringHunan University College of Integrated Circuits Zhejiang University Shenzhen Geim Graphene Center Shenzhen Key Laboratory of Layered Materials for Value-Added ApplicationsTsinghua-Berkeley Shenzhen Institute & Institute of Materials ResearchTsinghua Shenzhen International Graduate SchoolTsinghua University State Key Laboratory of Extreme Photonics and Instrumentation College of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZijingang CampusZhejiang University National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences CAS Key Laboratory of Nanophotonic Materials and devices & Key Laboratory of Nanodevices and Applications i-LabSuzhou Institute of Nano-Tech and Nano-Bionics (SINANO)Chinese Academy of Sciences College of Chemistry and Chemical Engineering Hunan University Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education) Department of PhysicsRenmin University of China School

Over the past 70 years, the semiconductor industry has undergone transformative changes,largely driven by the miniaturization of devices and the integration of innovative structures and materials. Two-dimensional(2D) materials like transition metal dichalcogenides(TMDs) and graphene are pivotal in overcoming the limitations of silicon-based technologies, offering innovative approaches in transistor design and functionality, enabling atomic-thin channel transistors and monolithic 3D integration. We review the important progress in the application of 2D materials in future information technology, focusing in particular on microelectronics and optoelectronics. We comprehensively summarize the key advancements across material production, characterization metrology, electronic devices, optoelectronic devices, and heterogeneous integration on silicon. A strategic roadmap and key challenges for the transition of 2D materials from basic research to industrial development are outlined. To facilitate such a transition, key technologies and tools dedicated to 2D materials must be developed to meet industrial standards, and the employment of AI in material growth, characterizations, and circuit design will be essential. It is time for academia to actively engage with industry to drive the next 10 years of 2D material research.

关键词： two-dimensional (2D) materials information technology production technology standardization of characterization microelectronicdevices optoelectronic devices multi-functional integration

天体物理学讲座第三讲恒星形成:从星际分子云到原始行星系统

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

物理 2001年第11期30卷 712-716页

作者：杨戟中国科学院紫金山天文台南京210008

对行星系统起源问题的研究在近年来已经取得很大进展 .一方面是星际分子云与恒星形成的天文研究取得了令人瞩目的成就 .研究表明 ,包括太阳在内的恒星是由冷暗的星际分子云收缩形成的 .在形成恒星的过程中 ,普遍伴随出现围绕恒星的盘状... 详细信息

对行星系统起源问题的研究在近年来已经取得很大进展 .一方面是星际分子云与恒星形成的天文研究取得了令人瞩目的成就 .研究表明 ,包括太阳在内的恒星是由冷暗的星际分子云收缩形成的 .在形成恒星的过程中 ,普遍伴随出现围绕恒星的盘状的原始行星系统 .在这种原始行星系统中间 ,尘埃颗粒逐渐生长 ,并凝聚成行星、彗星等 .从分子云到原始行星系统大约经历百万年 .而木星这样的大行星有可能在恒星收缩阶段同时形成 ,并且在行星系统的发展过程中逐渐发展 .行星系统起源的另一方面进展来自包括彗星、太阳系行星际探测 ,从而对太阳系这样的行星系统的组成和性质、对行星大气等有了更精确的了解 ,以此为参考 ,能够测定那些远离太阳系的其他新近发现的行星系统的物理化学性质 ,从而提供了一系列互相联系和对比的样本 .通过上述进展。

关键词：星际分子云恒星形成原始行星系统天体物理学

在线全文

学校读者我要写书评

暂无评论

太阳活动与长江中下游地区旱涝的规律

天文学报 1992年第2期33卷 179-185页

作者：孙长安杨本有中国科学院紫金山天文台南京210008

本文通过对太阳周不同时段旱涝频率的分析,得到长江中下游地区大面积旱涝存在22年和11年重现周期,这恰好与太阳黑子11年周期有关,在太阳周升时段以旱灾为主,平均旱涝比为3.2比1,经过5.5年左右到降时段,则以涝灾为主,平均涝旱比为1.8比1,... 详细信息

本文通过对太阳周不同时段旱涝频率的分析,得到长江中下游地区大面积旱涝存在22年和11年重现周期,这恰好与太阳黑子11年周期有关,在太阳周升时段以旱灾为主,平均旱涝比为3.2比1,经过5.5年左右到降时段,则以涝灾为主,平均涝旱比为1.8比1,第22太阳周峰年已经过去,粗略估计1996年是第23太阳周的谷年,因而在目前的降时段(最近几年),长江中下游地区以大涝为主,以后大涝再逐时段减少.在1990—1995年期间,预计发生大涝3次,大旱1次;在1995—1997年期间,大涝1次,大旱1次;在1997—2000年,大涝1次,大旱2次.

关键词：太阳活动旱涝规律灾情长江

First Digit Distributions of Gamma-Ray Bursts

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第5期24卷 70-75页

作者： Hou-yu Lai Jun-Jie Wei purple mountain observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

The occurrence of the first significant digits from real world sources is usually not equally distributed,but is consistent with a logarithmic distribution instead,known as Benford’s *** this work,we perform a comprehensive investigation on the first digit distributions of the duration,fluence,and energy flux of gamma-ray bursts (GRBs) for the first *** a complete GRB sample detected by the Fermi satellite,we find that the first digits of the duration and fluence adhere to Benford’s ***,the energy flux shows a significant departure from this law,which may be due to the fact that a considerable part of the energy flux measurements is restricted by lack of spectral *** on the conventional duration classification scheme,we also check if the durations and fluences of long and short GRBs (with duration T_(90)>2 s and T_(90)≤2 s,respectively) obey Benford’s *** find that the fluences of both long and short GRBs still agree with the Benford distribution,but their durations do not follow Benford’s *** results hint that the long–short GRB classification scheme does not directly represent the intrinsic physical classification scheme.

关键词： (stars:)gamma-ray burst general-methods statistical-astronomical databases miscellaneous

ERRATUM:“Statistical study of EUV and X-ray transient brightenings”(RAA, 10, 696 [2010])

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2010年第12期 1315-1315页

作者： Jing-Wei Li and Hui Li purple mountain observatory, Chinese Academy of Sciences, nanjing 210008, china

As a result of an author’s error, the paper "Statistical study of EUV and X-ray transient bright-enings" by Jing-Wei Li and Hui Li (RAA, 10, 696 [2010]) contains errors in the abstract and in page

关键词： EUV 2010 ERRATUM Statistical study of EUV and X-ray transient brightenings