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.

Since September 2018, LAMOST starts a new 5-year medium-resolution spectroscopic survey (MRS) using bright/gray nights. We present the scientific goals of LAMOST-MRS and propose a near optimistic strategy of the survey. A complete footprint is also pro-

Inspired by the molecular mechanics of mussel adhesive formation, a novel water-soluble fluorescent macromolecule (polydopamine-polyethyleneimine (PDA-PEI)) is prepared by one-pot copolymerization of dopamine (DA) and PEI. In this method, DA is polymerized to form PDA, which is then coupled with PEI mainly through Michael addition. The fluorescence property of PDA-PEI is mainly attributed to the Michael addition of PEI on the 5,6-dihydroxyindole (DHI) units of PDA, where PEI can form hydrogen bonds with oxidative products such as DHI and force the DHI units to twist out of plane, resulting in a decrease in the intra- and intermolecular coupling of PDA. In addition, the influence of various metal cations on the fluorescence of the PDA-PEI copolymer is investigated. This work may facilitate the development of new strategies for controlling the emission characteristics of PDA.

This paper presents a relative flux calibration method for the Guoshoujing Telescope (LAMOST), which may be applied to connect a blue spectrum to a red spectrum to build the whole spectrum across the total wavelength range (3700 ∼ 9000 Å).In each spectrograph, we estimate the effective temperatures of selected stars using a grid of spectral line indices in the blue spectral range and a comparison with stellar atmosphere models. For each spectrograph, stars of types A and F are selected as pseudo-standard stars, and the theoretical spectra are used to calibrate both the blue (3700 ∼ 5900 Å) and red spectrograph arms (5700 ∼ 9000 Å). Then the spectral response function for these pseudo-standard stars could be used to correct the raw spectra provided by the other fibers of the spectrograph, after a fiber efficiency function has been derived from twilight flat-field exposures. A key problem in this method is the fitting of a pseudo stellar continuum, so we also give a detailed description of this step. The method is tested by comparing a small sample of LAMOST spectra calibrated in this way on stars also observed by the Sloan Digital Sky Survey. The result shows that the T eff estimation and relative flux calibration method are adequate.

Hypervelocity stars are believed to be ejected out from the Galactic center through dynamical interactions of (binary) stars with the central massive black hole(s). In this letter, we report 13 metal-poor F-type hypervelocity star candidates selected from 370,000 stars of the data release 7 of the Sloan Digital Sky Survey. With a detailed analysis of the kinematics of these stars, we find that seven of them were likely ejected from the Galactic center (GC) or the Galactic disk, four neither originated from the GC nor the Galactic disk, and the other two were possibly ejected from either the Galactic disk or other regions. Those candidates which unlikely originated from the GC or the Galactic disk, may be explained by other mechanisms, like the tidal disruption of the Milky Way's dwarf galaxies in the Galactic potential, or the gravitational interactions with a massive black hole at the center of M31 or M32.

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Photoresponsive polymer with azobenzene pendant group (PDMAA-co-PAPA) was synthesized by radical polymerization of N,N-dimethylacrylamide (DMAA) and N-4-phenylazophenyl acrylamide (PAPA), and the characterization of the inclusion complexes of the PDMAA-co-PAPA with a-cyclodextrin (a-CD) were performed by FTIR, GPC, 1 H NMR, 2D NOESY, and UV-vis spectroscopy. It was found that the solubility of PDMAA-co-PAPA and a-CD inclusion complexes in aqueous solution showed tunable property, which could be triggered by alternating UV-vis light irradiation at a certain temperature due to the effect of molecular recognition of a-CD with azobenzene moiety in the polymer. After UV irradiation, the lower critical solution temperature (LCST) of the polymer aqueous solution increased slightly without a-CD while the LCST decreased sharply at presence of a-CD. Furthermore, UV spectroscopy showed that the photoisomerization of the polymer solution went on rapidly and reversibly, and 2D NOESY data suggested that the inclusion complexation of a-CD with trans azobenzene moiety and the decomplexation with cis azobenzene resulted in reversible solubility behavior when objected to UV and Vis light irradiation alternately.