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991.
讨论了如何将SOPC技术用于大天区多目标光纤光谱天文望远镜(LAMOST)项目的低分辨率光谱仪IP控制核的设计,并在NIOSⅡ软核基础上设计实现了光谱仪IP控制核。整个IP控制核主要分为底层电机控制单元和通信单元两部分。通过工业以太网,远程控制计算机可以方便地控制低分辨率光谱仪,使其完成指定动作。也可以从本地控制计算机上实行控制。设计中采用将步进电机控制器封装成IP再复用的方法,大大缩短了研发时间,减少错误的发生。通信控制中串口通信和以太网可以互为冗余,保证了通信的顺利进行。 相似文献
992.
北太行紫荆关基性岩体的成因: 岩石学和地球化学证据 总被引:3,自引:0,他引:3
通过对北太行紫荆关晚中生代基性岩体的岩石学和地球化学特征研究, 讨论其岩浆源区特征及成因.结果表明, 紫荆关岩体主要由橄榄二辉石岩、角闪辉长岩和闪长岩等岩石组成.橄榄二辉石岩具有明显的堆晶结构, 可能是堆晶成因, 而角闪辉长岩和闪长岩可能是堆晶形成之后的残余岩浆的结晶.闪长岩中的斜长石显示复杂的结构和成分环带, 相对富钠的核部见富钙斜长石叠加, 后者又向富钠斜长石演化.闪长岩中的单斜辉石也显示复杂的成分环带, 主要是最边部的MgO含量比紧邻的内侧辉石更高.这表明在闪长岩形成过程中有新的幔源高温富镁的岩浆注入.以上各岩石类型具有类似的地球化学性质, 包括较强的稀土分异((La/Yb)N比值为5.76~23.13), 高Sr/Y比值(50.95~146.13), 富集K、Sr、Ba等大离子亲石元素和LREE, 亏损Nb、Zr、Ti等高场强元素和HREE, Eu异常不明显.都显示富集的Sr-Nd同位素特征, ISr=0.7058~0.7066, εNd(t) =-13.8~-18.2.这些特征表明紫荆关基性岩体的母岩浆来源于EM1型富集地幔的部分熔融.橄榄辉石岩和角闪辉长岩具有类似的Nd同位素成分(主要为εNd(t) =-15.0~-16.6), 但形成较晚的闪长岩的εNd(t) 值却比较高(-13.8~-14.6), 也支持新的幔源岩浆在晚期的注入. 相似文献
993.
中国大陆新生代上地幔铅同位素特征 总被引:2,自引:0,他引:2
收集了新生代(含少量晚中生代) 301件幔源玄武岩的Pb同位素数据, 编制了系统的Pb同位素变化趋势(等值线) 图件, 现仅提供“中国大陆新生代上地幔的206Pb/204Pb比值变化趋势图”.图件显示, Pb同位素在南北方向的差异比较显著, 南北的界线大体从合肥-郑州-银川-汗腾格里峰, 结合Nd同位素的资料, 以206Pb/204Pb比值为18~18.5作为分界, 以北小于18~18.5;以南大于该值.此外初步辨认出该时期存在3种类型的地幔: 造山带地幔、裂谷型地幔及“非典型地幔”.与依据不同时代、各种类型的样品铅同位素的比值, 统一编制的“中国大陆岩石圈206Pb/204Pb比值变化趋势图”进行比较, 显示出在东北的西北部的206Pb/204Pb比值、南北向东经104°附近的高206Pb/204Pb比值区是否存在、渤海周边Pb异常区的强度以及华南DUPAL异常区问题等方面都有区别, 表明晚中生代-新生代时期, 中国大陆进入了一个新的软流圈地幔对流体系, 近代地幔并没有完全继承老地幔的全部特征而是被注入了新的软流圈物质.此外, 两张趋势图都显示了南北分块的特征, 而东西向的系统变化, 仅在近代Pb比值趋势图中华南块体的东南沿海地区出现, 暗示太平洋板块俯冲对中国大陆的影响处于次要地位. 相似文献
994.
We collected centric diatom Stephanopyxis palmeriana samples in coastal waters of Xiamen for characteristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual reproduction. The result showed that pre-illumination of 2-3h red light before darkness could induce sexualization of S.palmeriana, while the follow-up illumination of far red light could reverse the effect of red light, which is a featured reaction of phytochrome. The Southern Dot Blot was carried out to identify the type of phytochrome that induces the sexualization. The result also showed high homogeneity of DNA fragment of S. palmeriana with phyB, but phyA. This means the photoreceptor in the process of sexual reproduction of S. palmeriana is phytochrome B (phyB). 相似文献
995.
Yuan-Gui Yang School of Physics Electronic Information Huaibei Normal University Huaibei China 《中国天文和天体物理学报》2011,(2)
We present charge-coupled device (CCD) photometry for the short-period K-type binary EI CVn,observed on 2009 February 28 at the Xinglong Station of National Astronomical Observatories,Chinese Academy of Sciences.By using the Wilson-Devinney program,the photometric solution was first deduced from our V R observations.The results show that EI CVn is a W-type weak-contact binary with a mass ratio of qph=0.2834(±0.0010) and an overcontact degree of f=20.0%(±0.7%).The distorted light curves were modeled by a dar... 相似文献
996.
Qiang Liu Ji Yang Yan Sun Ye Xu Purple Mountain Observatory Chinese Academy of Science Nanjing China Graduate University of Chinese Academy of Sciences Beijing China 《中国天文和天体物理学报》2011,(6)
For the first time, the OMC-2/3 region was mapped in C2H (1-0), HC3N (10-9) and HNC (1-0) lines. In general, the emissions from all the three molecular species reveal an extended filamentary structure. The distribution of C2H cores almost follows that of the 1300μm condensations, which might suggest that C2H is a good tracer to study the core structure of molecular clouds. The core masses traced by HNC are rather ?at, ranging from 18.8 to 49.5 M , while also presenting a large span for those from C2H, rangi... 相似文献
997.
Qing-Hua Tan Yu Gao Zhi-Yu Zhang Xiao-Yang Xia Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of Sciences Beijing China Tianjin Astrophysics Center Tianjin Normal University Tianjin China 《中国天文和天体物理学报》2011,(7)
We present simultaneous observations of 12CO,13CO and C18O J=1-0 emission in 11 nearby(cz<1000 km s-1) bright infrared galaxies.Both 12CO and 13CO are detected in the centers of all the galaxies,except for 13CO in NGC 3031. We have also detected C18O,CSJ=2-1 and HCO+J=1-0 emission in the nuclear regions of M82 and M51.These are the first systematical extragalactic detections of 12CO and its isotopes from the PMO 14 m telescope.We have conducted half-beam-spaced mapping of M82 over an area of 4×2.5 and major... 相似文献
998.
Fan Li Xin-Wu Cao Key Laboratory for Research in Galaxies Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of Chinese Academy of Sciences Beijing China 《中国天文和天体物理学报》2011,(8)
A tight correlation between γ-ray and radio emission is found for a sample of BL Lacertae(BL Lac) objects detected by the Fermi Gamma-ray Space Telescope(Fermi) and the Energetic Gamma-Ray Experiment Telescope(EGRET) . The γ-ray emission of BL Lac objects exhibits strong variability,and the detection rate of γ-ray BL Lac objects is low,which may be related to the γ-ray duty cycle of BL Lac objects. We estimate the γ-ray duty cycle,δγ 0.11,for BL Lac objects detected by EGRET and Fermi. Using the empirical r... 相似文献
999.
Yong Zhang Gen-Rong Liu Yue-Fei Wang Ye-Ping Li Ya-Jun Zhang Liang Zhang Yi-Zhong Zeng Jie Zhang National Astronomical Observatories /Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China Key Laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology China Graduate University of Chinese Academy of Sciences Beijing China 《中国天文和天体物理学报》2011,(9)
A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror,and so the larger version is always pursued by astronomers and astronomical technicians.Instead of using a monolithic primary mirror,more and more large telescopes,which are currently being planned or in construction,have adopted a segmented primary mirror design.Therefore,how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infr... 相似文献
1000.
Li-Heng Yang Yun-Chun Jiang Jia-Yan Yang Yi Bi Rui-Sheng Zheng Jun-Chao Hong National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming China Graduate University of Chinese Academy of Sciences Beijing China 《中国天文和天体物理学报》2011,(10)
We present simultaneous observations of three recurring jets in EUV and soft X-ray (SXR), which occurred in an active region on 2007 June 5. By comparing their morphological and kinematic characteristics in these two different wavelengths, we found that EUV and SXR jets had similar locations, directions, sizes and velocities. We also analyzed their spectral properties by using six spectral lines from the EUV Imaging Spectrometer (EIS) onboard Hinode and found that these jets had temperatures from 0.05 to 2.... 相似文献