| The formation and evolution of Galaxies is one of the great outstanding problems of astrophysics. The metallicity abundance and kinematics of stars in Galactic disk is an important basis for discriminating the thin and thick disks, which provides fundamental constraints on the chemical evolution of this important component of the Galaxy. Investigating the relations of the stellar metallicity [Fe/H] with kinematics, and orbital parameters are very important to explain some questions in the chemical evolution of the Galactic disk. We constructed an unbiased stellar sample from the common objects of two large observations. The sample consists of 4004 disk stars in the solar neighborhood with the range of metallicity [Fe/H] from ~-1.0 to ~0.5, including 3855 thin disk stars and 146 thick disk stars. The range of their mean Galactocentric distances Rm is from ~4 to ~11 kpc, and the range of their maximum vertical distance from the Galactic Plane Zmax is from 0 to ~3.5 kpc. The relations of the stellar metallicity [Fe/H] with velocity dispersions, the age-velocity dispersion relation (AVR), [Fe/H] with the orbital eccentricity e, and [Fe/H] with Rm, as well as [Fe/H] with Zmax are investigated in detail. We find the kinematic properties are different and can be discriminated in the thick and thin disks. The main results and conclusions showed that:(1) The rotational velocities VLSR are distinct and well separated for the thin and thick disks, there is VLSR≥-60km/s for thin disk stars and -180km/s≤VLSR<-60km/s for thick disk stars. The velocity dispersions are also larger in the thick disk than in the thin disk. (σU,σV,σW)=(58±3,34±2,39±2)km/s, and (σU,σV,σW)=(31±1,18±1,15±1)km/s for the thick and thin disks, respectively.(2) The U, V, W velocity dispersions have an increasing trend with the age increasing, while there is a statistically significant and abrupt increase in all velocity components of the velocity dispersion at a stellar age of 10 Gyrs. The thin disk AVR show velocity dispersion in U and V seems to increase smoothly, with saturation in 41km/s and 22km/s at 8 Gyrs, respectively. The Velocity dispersion in W with saturation reaching 21km/s at 6 Gyrs. The AVR in thick disk shows no strong correlations. The existence of a velocity dispersion gap between the thin and thick disks.(3) The orbital eccentricity of disk stars decreases with increasing metallicity, while this trend becomes flat for stars with [Fe/H]>?0.2. The orbital eccentricities are distinct and well separated for the thin and thick disks, there is e < 0.20 for thin disk stars and e > 0.25 for thick disk stars.(4) There is a shallow radial iron abundance gradient with a slope of ?0.030 dex/kpc in the range 4.0 < Rm < 11.0 kpc for the Galactic disk as a whole, but the true radial gradient of the galactic disk maybe discontinuous at Rm≈8 kpc. For the thin disk, the metallicity gradient is discontinuous when moving from the innermost to the external disk regions: a slope of 0 dex/kpc in the inner disk (Rm < 8kpc), and a slope of ?0.12 dex/kpc in the outer disk (Rm≥8kpc). For the thick disk, there is no radial metallicity gradient.(5) The vertical gradient of iron abundance is steeper than the radial gradient, which is ?0.217 dex/kpc for the Galactic disk in general, and the gradient distribution is linearly continuous. In addition, the vertical abundance gradient of the thin disk (?0.251 dex/kpc) is larger than that of thick disk (?0.146 dex/kpc). Moreover, the vertical gradient shows an evolution trend with time, which the vertical iron gradient for the younger stars is considerably steeper than that for the older stars either for the thin disk or thick disk.
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