RICHARD Handl of Sweden has been arrested for building a tiny nuclear reactor (核反应堆) in his kitchen. Handl says that building reactors is just a hobby. The amateur (业余的) nuclear scientist mixed americium (镅), radium (镭), beryllium (铍) and sulfuric acid (硫磺酸) in a cooker, causing a small “melt down” on his stove (炉子) top. Authorities became concerned after Handl recorded his hobby on the Internet. The Swedish Radiation Safety Authority says that no neighbors were in danger of radiation (辐射).