EDUCATION OF ANALYTICAL METHOD FOR THE MIGRATION STUDY OF ENVIRONMENTAL PLUTONIUM

环境钚迁移研究分析方法的教学

基本信息

批准号：
11450198
负责人：
KUDO Akira
金额：
$ 9.41万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

An artificial single dose contaminant was released at Nagasaki, Japan on August 9,1945 detonating Plutonium (10-15kg) atomic bomb. A portion, 1.2 kg of 239Pu was fissioned releasing 21 kt TNT energy along with various fission products. The rest of the unexpended fissile material, 239+240Pu, 13.8 kg (3.49 x 10^<13> Bq), was dispersed into the atmosphere along with a fission product, 137Cs, 23.4 g (7.44 x 10^<13>Bq). The fate of 239+240Pu and 137Cs was investigated by analysing both local and global fallout. The highest concentration of 239+240Pu was 64.5 mBq/g (181 mBq/cm2) while it was 188 mBq/g (526 mBq/cm2) for 137Cs both at 2.8 km east from the hypocentre. The total amount of deposition in the local fallout region of 264 km2 was 37.5 g (9.48 x 10^<10>Bq) for 239+240Pu and 3.14 mg (5.88 x 10^<10>Bq) for 137Cs. The ratio of the local fallout against the total amount of the radionuclides released was 0.27% for 239+240Pu and 0.134% for 137Cs. Recent advancements in analytical technology made it possible for artificial radionuclides released from the Nagasaki explosion to be detected in the Arctic ice core layer of 1945. The 239+240Pu and the 137Cs, were measured by collecting 10 ice cores on the Agassiz ice cap, Ellesmere Island, Canada. The deposition was 0.16 μBq/cm2 for 239+240Pu and 20 μBq/cm2 for 137Cs. During the atmospheric testing, the deposition of 239+240Pu and 137Cs varied more than 100 times with the highest peaks of over 50 μBq/cm2 for 239+240Pu and over 800 μBq/cm2 for 137Cs both occurred in 1962. Analyzing Arctic data, there are many new information for long global transport, the history of nuclear weapons development etc.

1945年8月9日在日本长崎（Nagasaki）发行了一种人造单剂量污染物，爆炸prutating（10-15公斤）原子弹。一部分，1.2千克为239pu的裂变释放21 kt TNT能量以及各种裂变产物。其余意外的裂变材料，239+240pu，13.8 kg（3.49 x 10^<13> bq），与裂变产物，137cs，23.4 g（7.44 x 10^<13> bq）分散到大气中。通过本地和全球影响分析研究了239+240pu和137cs的命运。 239+240PU的最高浓度为64.5 MBQ/g（181 MBQ/cm2），而137C的浓度为188 MBQ/g（526 MBQ/cm2），均在距HypoSentre以东2.8 km的位置。对于239+240PU，局部辐射区域中264 km2的总存款量为37.5 g（9.48 x 10^<10> bq），137cs的总存款量为239+240PU和3.14 mg（5.88 x 10^<10> bq）。在239+240PU的局部影响与释放的放射线释放的总量为0.27％，而137C的比率为0.27％。分析技术的最新进步使得从长崎爆炸中释放出的人工放射线可以在1945年的北极冰核层中检测到。通过在加拿大Ellesmere Island的Agassiz Ice Cap，加拿大Ellesmere Island岛上收集10个冰块，测量了239+240PU和137CS。对于239+240PU的沉积物为0.16μBQ/cm2，对于137cs为20μBQ/cm2。在大气测试中，239+240PU和137cs的沉积量超过100倍，最高峰值超过50μbq/cm2的239+240PU和超过800μbq/cm2的最高峰对于137CS的最高峰值在1962年都发生在1962年。分析了许多新信息。