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On September 14–18, 2000, a medium-small solar active region was observed at Ganyu Station of Purple Mountain Observatory. Its spots were not large, but it had a peculiar active filament. On Sep.16, a flare of importance IIIb with rather intense geophysical effects was produced. Our computation of the magnetic structure of the active region reveals that the rope-shaped filament was concerned with a low magnetic arc close to magnetic neutral line. An intense shear of magnetic field occurred near magnetic rope. The QSL analysis shows that a 3-D magnetic reconnection might appear in the vicinity of filament, and this can be used to interpret the formation of a large flare. [Copyright &y& Elsevier]

On June 18, 2000, a small ejection phenomenon at the western limb of the sun was observed by Ganyu Station of Purple Mountain Observatory. Its lifetime was merely 15 minutes, and it did not belong to the ejection phenomena in late stages of solar flares. A very fine helical structure was visible. Assuming a velocity of 100 km/s produced by magnetic reconnection in the lower atmosphere and ignoring the Lorentz force, the height attainable by a column of ejecta of quasi-uniform density is derived, and the result is consistent with the observations. [Copyright &y& Elsevier]