The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST's special design allows both a large aperture (effective aperture of 3.6 m-4.9 m) and a wide field of view (FOV) (5 • ). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror's surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67 m×6.05 m) and active Schmidt mirror (5.74 m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects.
The Large sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 million spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2011 and ended in June 2012, and the data have been released to the public as the LAMOST Pilot Data Release in August 2012. The regular survey started in September 2012, and completed its first year of operation in June 2013. The LAMOST DR1 includes a total of 1202 plates containing 2 955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio (SNR) ≥ 10. All data with SNR ≥ 2 are formally released as LAMOST DR1 under the LAMOST data policy. This data release contains a total of 2 204 696 spectra, of which 1 944 329 are stellar spectra, 12 082 are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters: late A,FGK-type stars with high quality spectra (1 061 918 entries), A-type stars (100 073 entries), and M-type stars (121 522 entries). This paper introduces the survey design, the observational and instrumental limitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided.
This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information about the FITS headers of spectra are also introduced. The released data set includes 319 000 spectra and a catalog of these objects.
Vanadium(III) complexes bearing salicylaldiminato ligands (2a-k) [RNdCH(ArO)]VCl 2 (THF) 2 (Ar ) C 6 H 4 , R ) Ph, 2a; p-CF 3 Ph, 2b; p-CH 3 Ph, 2c; 2,6-Me 2 Ph, 2d; 2,6-iPr 2 Ph, 2e; cyclohexyl, 2f; Ar ) C 6 H 3 tBu(2), R ) Ph, 2g; 2,6-iPr 2 Ph, 2h; Ar ) C 6 H 2 tBu 2 (2,4), R ) Ph, 2i; 2,6-iPr 2 Ph, 2j; Ar ) C 6 H 2 Br 2 , R ) Ph, 2k) were prepared from VCl 3 (THF) 3 by treating with 1.0 equiv of (RNdCH)ArOH in tetrahydrofuran (THF) in the presence of excess triethylamine (TEA). The reaction of VCl 3 (THF) 3 with 2.0 equiv of (RNdCH)ArOH in THF in the presence of excess TEA afforded vanadium(III) complexes bearing two salicylaldiminato ligands (3a-k), [RNdCH(ArO)] 2 VCl(THF) x (Ar ) C 6 H 4 , x ) 1, R ) Ph, 3a; p-CF 3 Ph, 3b; p-CH 3 Ph, 3c; 2,6-Me 2 Ph, 3d; 2,6-iPr 2 Ph, 3e; cyclohexyl, 3f; Ar ) C 6 H 3 tBu(2), x ) 1, R ) Ph, 3g; x ) 0, 2,6-iPr 2 Ph, 3h; Ar ) C 6 H 2 tBu 2 (2,4), x ) 1, R ) Ph, 3i; 2,6-iPr 2 Ph, x ) 0, 3j; Ar ) C 6 H 2 Br 2 , x ) 1, R ) Ph, 3k). These complexes were characterized by FTIR and mass spectra as well as elemental analysis. Structures of complexes 2a, 2b, 2g, 2i, 2k, 3b, 3c, 3e, 3j, and 3k were further confirmed by X-ray crystallographic analysis. The complexes were investigated as catalysts for ethylene polymerization in the presence of Et 2 AlCl. Complexes 2a-k exhibited high catalytic activities (up to 22.3 kg PE/mmol V · h · bar) and afforded high molecular weight polymers (M w > 100 kg/mol) with unimodal molecular weight distributions at room temperature, while displaying relatively low catalytic activities, and produced polymers with low molecular weight (M w < 30 kg/mol) and broad molecular weight distributions at 70°C. Complexes 3a-k were also effective catalyst precursors for ethylene polymerization. Even at 70°C these complexes produced polyethylenes with unimodal distributions. These results indicated that the structural model of the salicylaldiminato vanadium(III) complexes greatly affected the ethylene polymerization behaviors.
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