中文摘要：

根据SDO／AIA（SolarDynamicsObservatory／Atm08pheric Imaging Assembly）2013年12月25日到26日的171A观测，发现在活动区NOAA11931西南同一区域连续发生了一系列同源喷流事件，选取了其中的12次比较典型的喷流作了分析研究．与大部分喷流有关的磁场结构在抛射的过程中都有明显的解缠运动，少部分的几个没有．有的喷流的过程可以分为两个阶段：慢速无解缠抛射阶段和快速解缠抛射阶段．有的喷流在发生前，观测到有亮点沿着磁拱底部从远离喷流的一端向靠近喷流的一端延伸，而在喷流过程当中，靠近磁拱底部的区域有两部分磁力线同时在做旋转运动．在最后一次喷流过程中，喷流底部的磁结构东南端有两个磁拱先后出现，同时在西北端有一个小磁环浮现出来．对比SDO／HMI（Helioseismic and MagneticImagerl的视向磁图发现，大约在第1次喷流出现之前4h，一对正负磁极从有关磁结构的底部浮现，并且在整个喷流事件过程中一直在上浮．虽然在这12次喷流发生前后底部磁场整体上是浮现的，但是具体到每个喷流底部磁场的变化也不尽相同，有的喷流底部的磁拱附近磁场既有浮现过程又有对消过程，而有的喷流底部磁场附近只有明显磁浮现或者磁对消过程．

英文摘要：

According to SDO/AIA （Solar Dynamics Observatory/Atmospheric Imag- ing Assembly） 171A observation, a series of homologous jets are found in the southwest area of active region NOAA 11931 from 2013 December 25 to 26, from which 12 typical jets are selected to analyze and study. During the eruption process, the magnetic field structure of most jets have obvious untwisting movement, though a few of them don＇t. The movement of some jets can be divided into two phases： slow no untwisting movement, and rapid twisting movement. Before some jets start, a bright point grows along the base arcade, from the distant end of jet to the close end, and two kinds of magnetic field structures untwist near the base simultaneously during the ejection pro- cess. During the process of the last jet, two magnetic arcades appear to the southeast of the base arcade, and a magnetic loop emerges to the northwest of the base arcade. Compared with the SDO/HMI （Helioseismic and Magnetic Imager） line-of-sight magne- togram, about 4 h before the first jet appears, a magnetic bipolar emerges from the jet ejection region, and the bipolar continuously emerges during the recurrent jets. Even though the magnetic field emerges on the whole, for every single jet, the change pattern is different from one another： for some jets, there is not only magnetic emerging, but also magnetic cancellation occurs near the base arcade; however, for some jets, there is only obvious emerging or cancellation.