“The type of accident that is occurring in Japan is known as the ___1___: loss of off-site AC power—power lines are down—and then a subsequent failure of emergency power on-site, the diesel generators. ___2(句子)___.”
Physicist Ken Bergeron, speaking on March 12 during a ___3___. He worked on nuclear reactor accident analysis at Sandia National Laboratories.
“The probability is hard to calculate primarily because of the possibility of what are called ___4___, where the loss of off-site power and of on-site power are caused by the same thing. In this case the earthquake and tsunami. We’re hoping that all of the barriers to release of radioactivity will not fail. So far the first barrier, which is the fuel cladding, has apparently failed, because they are detecting cesium. We now have to hope that the ___5___, including primarily the containment building, will succeed in preventing release of major amounts of radioactivity.”

【视听版科学小组荣誉出品】
station blackout The station blackout has been one of the great concerns for decades. press briefing common-cause accidents subsequent layers
“日前日本核电站发生的事故类型属核电站断电：站外交流电断路——核电站停电——站内用以紧急供电的柴油发电机也因此失效。几十年来，核电站断电一直是令人提心吊胆的问题之一。” 物理学家肯•伯杰龙在桑迪亚国家实验室做过核反应堆事故模拟的研究。3月12日，这是他在某新闻简报中的讲话。“发生此类事故的概率很难估计，因为发生由于同种因素导致核电站内外同时断电的概率难以计算。而发生此次事故，就是因为地震和海啸。我们希望隔绝放射性物质的屏障不要全部失效。目前，第一道屏障——燃料包壳，已经明显失去功用，因为专家已经在核电站附近检测到了铯元素。现在我们只能希望包括遏制建筑在内的后面几道屏障能够成功隔绝大量放射性物质。”