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Calculations for the Pre-Calibration of LAMOST Active Optics

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chinese Journal of Astronomy and Astrophysics 2005年第3期5卷 302-314页

作者： Yong Zhang and Xiang-Qun Cui national astronomical Observatories / Nanjing Institute of astronomical Optics & Technology, chinese academy of sciences, Nanjing 2.0042.Graduate School of the chinese academy of sciences, beijing 100039 Graduate School of the chinese academy of {2. Beijing 100039

Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) is one of the major on-going national large scientific projects in china. Active optics is a {2. technology for the LAMOST with which the thin-mirror active optics and segmented-mirror active optics are tied in. A pre-calibration method considering all active forces and displacements specially for LAMOST has been developed in early 2.04. We give a detailed mathematical derivation and calculation including numerical simulation and computer program realization of the pre-calibration method of LAMOST open-loop control for the third-order aspherical aberration. We have also carried out calculations on the application of the pre-calibration method and the parameters of actuator design in LAMOST active optics in observation mode, including estimations of the actuator ranges, the interval of active optics correction and the ranges and trends of load changes on all the actuators during LAMOST tracking a given star.

关键词： active optics telescopes instrumentation

Metallicity calibration for solar type stars based on red spectra

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Research in Astronomy and Astrophysics 2011年第5期11卷 563-576页

作者： Jing-KunZhao GangZhao Yu-QinChen A-LiLuo keylaboratoryofOpticalAstronomy NationalAstronomicalObservatoriesChineseAcademyofSciencesBeijing100012China

Based on a high resolution and high signal-to-noise ratio （S/N） spectral analysis of 90 solar-type stars, we have established several new metaUicity calibrations in the Tefr range [5600, 6500] K based on red spectra with the wavelength range of 560-880 nm. The new metallicity calibrations are applied to determine the metallicity of solar analogs selected from Sloan Digital Sky Survey （SDSS） spectra. There is a good consistent result with the adopted value presented in SDSS-DR7 and a small scatter of 0.2. dex for stars with S/N 〉 50 being obtained. This study provides a new reliable way to derive the metallicity for solar-like stars with low resolution spectra. In particular, our calibrations are useful for finding metal-rich stars, which are missing in the SEGUE Stellar Parameter Pipeline.

关键词： techniques: radial velocities - stars: temperatures - stars: abundances

Spectroscopic and photometric observations of unidentified ultraviolet variable objects in the GUVV-2.Catalog

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Research in Astronomy and Astrophysics 2011年第7期11卷 833-842页

作者： You Li Jing Wang Jian-Yan Wei Xiang-Tao He Department of Astronomy Beijing Normal University Beijing 100875 China national astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

An NUV-optical diagram composed from sources from the second Galaxy Evolution Explorer（GALEX） Ultraviolet Variability（GUVV-2. Catalog provides us with a method to tentatively classify the unknown GUVV-2.sources by their NUV-optical *** the purpose of testing the correctness and generality of the method,we carry out a program on the spectroscopic observations of the unidentified GUVV-2.*** spectroscopic identification of these 37 sources are 19 type-A to-F stars,10 type-G to-K stars and 7 M dwarf stars together with an *** also present the light curves in the R-band for two RR Lyrae star candidates selected from the NUV-optical diagram,both of which undergo cyclic *** their light curves and colors,we classify them as RR Lyrae *** confirm the re-sults,we show a color-color diagram for the 37 newly identified spectroscopic objects compared with previously identified ones,which are consistent with our previous re-sults,indicating that the ultraviolet variable sources can initially be classified by their NUV/optical color-color diagram.

关键词： stars:variables:general—galaxies:active—methods:observational—ultraviolet emission

A cyclic behavior of CME accelerations for accelerating and decelerating events

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Research in Astronomy and Astrophysics 2009年第10期9卷 1165-1172页

作者： Peng-Xin Gao Ke-Jun Li national astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate University of chinese academy of {2. Beijing 100049 China

We investigate the cyclic evolutionary behavior of CME accelerations for accelerating and decelerating CME events in cycle 2. from 1997 January to 2.07 December. It is found that the absolute values of semiannual mean accelerations of both accelerating and decelerating CME events roughly wax and wane in a cycle, delaying the sunspot cycle in time phase. We also investigate the semiannual number of CMEs with positive and neg- ative acceleration and find that there are more decelerating CME events than accelerating CME events during the maximum period of a cycle （about three years）, but there are more accelerating CME events than decelerating CME events during the rest of the time interval of the cycle. Our results seem to suggest that the different driving mechanisms may be acting accelerate and decelerate CME events; for accelerating CME events, the propelling force （Fp） statistically seems to play a significant role in pushing CMEs outward; for decelerating CME events, the drag （Fd） statistically seems to play a more effective role in determining CME kinematic evolution in the outer corona. During the maximum period of a cycle, because of the V^2.dependence, Fd is generally stronger; because of the magnetic field dependence, Fp is also generally stronger. Thus, the absolute values of both the negative and positive accelerations are generally larger during that time. Because of the V^2.dependence, Fd may be more effective during the maximum period of a cycle. Hence, there are more decelerating CME events than accelerating CME events during that time. During the minimum time interval of a cycle, CMEs have relatively small speeds, and Fp may be more effective. Therefore, there are more accelerating CME events than decelerating CME events during that time.

关键词： Sun corona -- Sun coronal mass ejections (CMEs)

Can Asymmetry of solar activity be Extended into Extended Cycle?

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chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 66-70页

作者： Ke－JunLi Jing－XiuWang 等 YunnanObservatory ChineseAcademyofSciencesKunming650011 nationalastronomicalObservatories ChineseAcademyofSciencesBeijing100012

With the use of the Royal Greenwich Observatory data set of sunspot groups, an attempt is made to examine the north-south asymmetry of solar activity in the 'extended' solar cycles. It is inferred that the asymmetry e... 详细信息

关键词： Sun: sunspot - Sun: active cycle - Sun: activity

Induction of nicotine in tobacco by herbivory and its relation to glucose oxidase activity in the labial gland of three noctuid caterpillars

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chinese Science Bulletin 2004年第15期49卷 1596-1601页

作者： ZONG Na1,2.& WANG Chenzhu1 1.State key laboratory of Integrated Management of Insects & Rodents,Institute of Zoology,{2. academy of sciences.beijing 100080,china 2.Graduate School of {2. academy of sciences.beijing 100080,china Correspondence should be addressed to Wang Chenzhu(e-mail: czwang@***) State key laboratory of Integrated Management of Insects & Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100080 China Graduate School of chinese academy of {2. Beijing 100080 China

Tobacco Nicotiana tabacum L. is a host plant of Helicoverpa armigera (Hübner), Helicoverpa assulta Guenée and Spodoptera litura (Fabricius) (Lepidoptera, Noctuidae). The difference in leaf nicotine response to the feeding by these three larvae and the mechanical simulation of their feeding was examined by HPLC. Results indicated that nico- tine induction was suppressed by H. armigera and H. assulta larvae feeding or by simulated damage treated with their labial glands extracts. The production of nicotine was also suppressed by the glucose oxidase from Aspergillus niger when it was treated on mechanically wounded leaf area. On the contrary, the nicotine production was stimulated by S. litura larva feeding or by simulated damage treated with its labial gland extract. Heat denature can not counteract the stimulation effect of the S. litura labial gland extracts to to- bacco nicotine production. The glucose oxidase activity was detected in labial gland extracts of both H. armigera and H. assulta, but the activity in H. armigera was significantly higher than that in H. assulta. No glucose oxidase activity was detected in labial gland extracts of S. litura. It is shown that the glucose oxidase activity in labial glands of caterpil- lars plays an important role in the nicotine response to her- bivory. The glucose oxidase was mainly contained in the la- bial gland of H. armigera larva, and had the highest activity at pH 7.0. D-Glucose was the optimal substrate of the glucose oxidase. Labial gland glucose oxidase activities varied daily during larval development with high activities found when larvae were actively feeding.

关键词：烟碱烟草葡萄糖氧化酶三夜蛾毛虫棉铃虫烟毒虫斜纹夜蛾

Further study on Ca_(2.) -mediated inhibition of human erythrocyte D-glucose transporter

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chinese Science Bulletin 1997年第10期42卷 871-875页

作者： XIE Wensheng, TU Yaping and YANG FuyuState key laboratory of Biomacromolecules, Institute of Biophysics, {2. academy of sciences, beijing 100101, china State key laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing China

THE transport of D-glucose to erythrocytes is catalyzed by an integral membrane protein,*** D-glucose *** specifically carries D-glucose,driven by glucose’s *** of its relative abundance and higher transport activity... 详细信息

关键词： Ca2. glucose transporter transporting activity inhibition.

Anisotropic Beam Model for the Spectral Observations of Radio Burst Fine Structures on 1998 April 15

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chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 475-482页

作者： V.G. LedenevE-mail:yyh@*** , Yi-Hua Yan, and Qi-Jun Fu (national astronomical Observatories, {2. academy of sciences, beijing 100012) (Institute of solar-Terrestrial Physics, Siberian Division of Russian academy of sciences 664033, Irkutsk, P. 0 Institute of solar-Terrestrial Physics Siberian Division of Russian Academy of Sciences 664033 Irkutsk P. O. Box 4026 Russia

A fine structure consisting of three almost equidistant frequency bands was observed in the high frequency part of a solar burst on 1998 April 15 by the spectrometer of beijing {2. Observatory in the range 2.6-3.8 GHz. A model for this event based on beam-anisotropic instability in the solar corona is presented. Longitudinal plasma waves are excited at cyclotron resonance and then transformed into radio emission at their second harmonic. The model is in accordance with the observations if we suppose a magnetic field strength in the region of emission generation of about 2.0 G.

关键词： Sun: radio radiation Sun: activity - Sun: corona

Virus rejection with two model human enteric viruses in membrane bioreactor system

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Science china Chemistry 2007年第3期50卷 397-404页

作者： ZHENG Xiang1,2.& LIU JunXin1 1 Research Center for Eco-Environmental sciences, chinese {2. of sciences, beijing 100085, china 2.School of Environment & Natural Resources, Renmin University of china, beijing 100872. china 1. Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China 2. School of Environment & Natural Resources Renmin University of China Beijing 100872 China

A membrane bioreactor (MBR) with gravity drain was tested for virus rejection with two coliphages, T4 and f2. which were used as surrogates for human enteric viruses. Virus rejection was investigated by PVDF and PP membrane modules, with the pore sizes of 0.2. and 0.1 μm, respectively. In tap water system, 2.1 lg rejection of coliphage T4 could be achieved by PVDF membrane compared with complete rejection by PP membrane, while for coliphage f2.with smaller diameter, 0.3―0.5 lg rejection of the influent virus was removed by the two membranes. In domestic wastewater system, cake layer and gel layer on the membrane surface changed the cut-off size of the membrane so that there was no significant difference between PP and PVDF for each coliphage. The removal ratios of coliphage T4 and f2.in the MBR were more than 5.5 and 3.0 lg, respectively. Compared with 5.5 lg removal for virus T4 in the MBR system, only 2.1 lg (96.8%―99.9%) removal rate was observed in the conventional activated sludge system with the influent virus concentration fluctuating from 1830 to 57000 PFU/mL. Only 0.8%―2.% virus removal was the effect of adsorption to activated sludge, which showed a decreasing tendency with the retention time, while 75%―98% was the effect of virus inactivation by microbial activity. It indicated that the major mechanism of virus removal was not the transfer of viruses from the water phase to the sludge phase but inactivation in the biological treatment process.

关键词： MBR model virus enteric virus inactivation