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1.
Zhi Xu Cheng Fang Wei-Qun Can Astronomy Department of Nanjing University Nanjing Purple Mountain Observatory Chinese Academy of Sciences Nanjing 《中国天文和天体物理学报》2005,5(5):519-530
Chromospheric lines, including Ha, Lyα, Lyβand CaⅡK, CaⅡ8542, are systemically and quantitatively investigated with respect to the non-thermal excitation and ionization due to particle beam bombardment for a series of solar semi-empirical atmospheric models. As a result we propose to use the contrast in the integrated intensity of hydrogen lines to estimate the total energy flux of the bombarding beam during the solar flare impulsive phase. Partial frequency redistribution is considered in the Lyαline calculation and a smaller intensity enhancement in the Ha line-centers is found than in the previous results of Fang et al. 相似文献
2.
A radiative seasonal model which incorporates a multilayer radiative transfer treatment at wave-lengths longward of 7 μm is presented and applied to Saturn's stratosphere. Opacities due to H2-He, CH4, C2H2, and C2H6 are included. Season-dependent insolation is shown to produce a strong hemispheric asymmetry decreasing with depth at the Voyager encounter times, and seasonal amplitudes of 30°K at the poles are predicted in the high stratosphere. The ring-modulated dependence of the insolation and the orbital eccentricity are shown to have a significant effect. Calculations agree closely with the Voyager 1 and 2 radio occultation ingress profiles recorded at 76°S and 36.5°S for CH4/H2 = 3.5 + 1.4/? 1.0 × 10?3;the estimated errors include modeling systematic errors and uncertainties in the occultations profiles. The possible role of aerosols in the stratospheric heating is analyzed. The Voyager 2 egress profile recorded at 31°S cannot be reproduced by calculations. Some constraints on the C2H2 and C2H6 abundances are derived. The upper portion of the occultation profiles (p < 3mbar) can be matched for C2H2/H2 = 1.0 + 1.3/?0.6 × 10?7, C2H6/H2 = 1.5 + 1.8/?0.9 × 10?6 at 76°S and C2H2/H2 = 4 + 6/?4 × 10?8, C2H6/H2 = 6 + 9/?6 × 10?7 at 36.5°N. At the northern occultation latitude, the discrepancy with the concentrations derived from analysis of IRIS spectra by R. Courtin, D. Gautier, A. Marten, B. Bézard, and R. Hanel (1984, Astrophys. J.287) can be explained by a sharp variation of the mixing ratios of these gases with altitude in the upper stratosphere. Other interpretations are discussed. 相似文献
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为建立社会主义市场经济的地矿工作新秩序,本文对国有地矿企业的经营者(厂长、经理)这一特殊群体进行了分析。着重研究了新形势下企业经营者实行年薪制的问题。指出年薪制就是以企业一个生产经营周期为单位确定经营者的报酬,这一周期通常为一年。进而阐述了为什么要实行企业经营者年薪制;企业经营者的收入应与职工工资完全脱钩;采用基础报酬加效益报酬的方法确定收入等等。并构想了实行经营者年薪制所需要的外部环境:建立经营者人才市场、经营者要能进能出、实行任职资格制度、建立风险机制、按劳动力市场经济规律办事。 相似文献
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从ROSAT巡天和定点观测结果的对比出发,发现了几个低银纬的巡天源表中的X射线源在定点观测中没有出现.本文计算了在这些位置的定点观测中出现点源的流强上限,发现比巡天源表中这些源的流强值低很多,这表明它们的流强变化很大,可能是X射线双星系统中的一类———X射线暂现源. 相似文献
6.
R. G. Gratton G. Bonanno P. Bruno A. CalÍ R. U. Claudi R. Cosentino S. Desidera F. Diego G. Farisato G. Martorana M. Rebeschini S. Scuderi 《Experimental Astronomy》2001,12(2):107-143
SARG is a cross dispersed echelle spectrograph in operation since late spring 2000 at the Italian Telescopio Nazionale Galileo
(TNG) 3.5 m telescope, La Palma. SARG offers both single object and long slit (up to 26 arcsec) observing modes covering a
spectral range from λ = 0.37 up to1 μm, with resolution ranging from R = 29,000 up to R = 164,000. Cross dispersion is provided by means of a selection of four grisms; interference filters may be used for the
long slit mode (up to 26 arcsec). A dioptric camera images the cross dispersed spectra onto a mosaic of two 2048 × 4096 EEV
CCDs (pixel size: 13.5 μm) allowing complete spectral coverage at all resolving power for λ < 0.8 μm. In order to reach a
high wavelength calibration precision an iodine-absorbing cell is provided. A Distributed Active Temperature Control System
(DATCS) maintains constant the temperature of all spectrograph components at a preset value. Early results show that SARG
works according to original specifications in terms of wavelength coverage, efficiency (measured peak efficiency is about
13%),resolution (maximum resolution R = 164,000 using a 0.3 arcsec slit, R ∼144,000 using an image slicer), and stability (preliminary estimates of radial velocity accuracy is ∼3 m/s using the iodine
cell and ±150 m/s without the iodine cell).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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STUDY ON GIS FOR YIELD ESTIMATION BY REMOTE SENSING IN JILIN MAIZE BELTSTUDYONGISFORYIELDESTIMATIONBYREMOTESENSINGINJILINMAIZ... 相似文献
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HUANGGuoqiang DONGShuanglin WANGFang 《中国海洋大学学报(英文版)》2005,4(1):56-60
Attractabilities of different diets and dietary selectivity of Chinese shrimp, Fenneropenaeus chinensis were studied through behavior observation and feeding experiment, respectively. The five diets used in the experiment are: Fish Flesh (FF), Shrimp Flesh (SF), Clam Foot (CF), Polychaete Worm (PW), and Formulated Diet (FD). No significant differences of attractability exist between any two different diets when every two natural diets or all five diets are provided simultaneously. On the other hand, significant differences of attractability exist between FD and every single natural diet when they are provided simultaneously. Results of behavioral observation indicate that natural diets are more attractive than FD. In feeding experiment, Chinese shrimp has distinct selectivity on different diets. It positively selects CF and PW, negatively selects FF and SF, and excludes FD absolutely. The results of the present studies indicate that the dietary selectivity of shrimp was based not only on the attractabilities of the diets, but also on the responses such as growth and food conversion. 相似文献