By statistical analyzing and contracting the two dimensional line-of-sight velocity fields which measured in Hα line, Hα fine structure and photospheric magnetic fields distributed in the same areas of quiet solar disk, we obtain the following most interesting results: (1) The correlation between chromospheric Hα absorption network and photospheric magnetic fieids (i.e. supergranulation boundary regions) is confirmed. (2) Most of magnetic network of quiet solar disk are mono-polarity, so that the nearby magnetic flux tubes in the network generally not form loops. (3) There are horizontal motions toward the network in chromosphere. And those motions are even evidenter in the vicinity of the network which is /found to exist upward motion. (4) The higher velocity regions in chromospheric network are not always corresponding to the stronger magnetic fields areas in photosphere. Some of them, in particular for upward motions, are corresponding to weaker magnetic fields areas in photosphere. (5) Most of bright mottles have upward motion features. But dark mottles have both upward and downward motion features almost in the same. (6) For individual flux tubes in the network, they are mainly upward motions. But for whole network, downward motion is its statistcal feature. Based on our results and previous workes in this field, we propose an idea that some spicules are results of a resonant buffeting of sides of mottles in the chromospheric network by periodic horizontal motions. For a critical wavespeed, the mottle drew energe from horizontal buffeting motions in maxism efficiency to accelerate its motion. We illustrate this effect in linear model by considering a two dimensional flux tube, i.e. mottle, embedded in an uniform compressible atmosphere. The instablity of the structure of the flux tube is discussed briefly from the dispersion relation which is drived from linera turbulent plasma equations of inside and outside of the flux tube.
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