very good site explaining what happened: http://spectrum.ieee.org/tech-talk/energy/nuclear/explainer-what-went-wrong-in-japans-nuclear-reactors http://spectrum

very good site explaining what happened: http://spectrum.ieee.org/tech-talk/energy/nuclear/explainer-what-went-wrong-in-japans-nuclear-reactors http://spectrum.ieee.org/tech-talk/energy/nuclear/explainer-...