1、Nuclear Power Plant Accidentsw 1952 Dec. 12, Chalk River, nr. Ottawa, Canadaw 1957 Oct. 7, Windscale Pile No. 1, north of Liverpool, England w South Ural Mountains:w 1976 nr. Greifswald, East Germanyw 1979 March 28, Three Mile Island, nr. Harrisburg, Pa.w 1986 April 26, Chernobyl, nr. Kiev, Ukrainew
2、 1999 Sept. 30, Tokaimura, JapanNuclear Power Plant Accidentsw 1952 Dec. 12, Chalk River, nr. Ottawa, Canada: a partial meltdown of the reactors uranium fuel core resulted after the accidental removal of four control rods. Although millions of gallons of radioactive water accumulated inside the reac
3、tor, there were no injuries.w 1957 Oct. 7, Windscale Pile No. 1, north of Liverpool, England: fire in a graphite-cooled reactor spewed radiation over the countryside, contaminating a 200-square-mile area. Nuclear Power Plant Accidents w South Ural Mountains: explosion of radioactive wastes at Soviet
4、 nuclear weapons factory 12 mi from city of Kyshtym forced the evacuation of over 10,000 people from a contaminated area. No casualties were reported by Soviet officials.w 1976 nr. Greifswald, East Germany: radioactive core of reactor in the Lubmin nuclear power plant nearly melted down due to the f
5、ailure of safety systems during a fire.Nuclear Power Plant Accidents w 1979 March 28, Three Mile Island, nr. Harrisburg, Pa.: one of two reactors lost its coolant, which caused overheating and partial meltdown of its uranium core. Some radioactive water and gases were released.Nuclear Power Plant Ac
6、cidentsw 1986 April 26, Chernobyl, nr. Kiev, Ukraine: explosion and fire in the graphite core of one of four reactors released radioactive material that spread over part of the Soviet Union, eastern Europe, Scandinavia, and later western Europe. 31 claimed dead. Total casualties are unknown. Worst s
7、uch accident to date.Nuclear Power Plant Accidentsw 1999 Sept. 30, Tokaimura, Japan: uncontrolled chain reaction in a uranium-processing nuclear fuel plant spewed high levels of radioactive gas into the air killing one worker and seriously injuring two others. Japans worst nuclear accident.Red Sun Streaming 太陽的融合反應w 太陽的輻射功率 = 3.9 1026 Ww 如為化學反應，以太陽質量，僅能維持 1000年；如為重力收縮 107年，但太陽的壽命已有 50億年，不可能是核分裂，因為沒那麼多鈾。 w 結論 : 融合反應（ P-P cycle） P-P cycle 1點火溫度：一千五百萬度氫 氦 P-P cycle 2w 氫燒完之後呢 ? 星球的演變 w 恆星是製造重元素的工廠 w 2個 (質子 ) 發生融合的機率 10-26，因此不會如同氫彈般爆炸。但恆星內部的氫密度極高，既使反應機率極低，仍可維持穩定的融合反應。另一方面，此反應之速率太慢，在地球上無法進行。
