Based on observations carried out at the Beijing Astronomical Observatory, Xinglong, PR China.

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Tables 3, 4 and 5 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html or
http://www.edpsciences.org

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...)

In the present work, U is defined to be positive in the anticentric direction.

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... iron

Here and in the following sections and figures, the iron abundance is the mean abundance derived from all Fe I and Fe II lines with equal weight to each line.

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