ストロンチウムイソトープ: 1965年5月14日の中国の核爆発後の世界的な循環
まとめ
1965年の中国の核実験で発生した放射性ストロンチウム-89とストロンチウム-90が,世界中に散らばった. この現象は,東京で観測されたストロンチウム-89/ストロンチウム-90比の有意な増加を引き起こした.
科学分野:
- 環境科学 環境科学
- 核化学 核化学とは
- 大気科学 大気科学
背景:
- 核兵器の実験は,放射性同位体を大気中に放出します.
- ストロンチウムイソトープは,Sr-89やSr-90のように,重要な分裂産物である.
- グローバルな大気循環パターンは,これらの同位体を世界中に分布させます.
研究 の 目的:
- ストロンチウム-89とストロンチウム-90の大気中の分散を追跡する.
- 降水中のストロンチウム-89とストロンチウム-90の比率を分析する.
- 特定の核事象が地球規模の放射性降下物パターンに与える影響を決定する.
主な方法:
- 大気中の放射性核素濃度の監視.
- ストロンチウムイソトープの降水サンプルを採取,分析する.
- 雨水のSr-89/Sr-90比率を計算する.
主要な成果:
- 1965年の中国の核実験のストロンチウム-89とストロンチウム-90は,急速に地球を回った.
- 1965年6月12日の東京の降雨では,Sr-89/Sr-90比の明確なピークが観察されました.
- この研究は,核降下物の地球規模の大気輸送の速度を示しています.
結論:
- 核降下物の世界的な分散は急速に進んでいます.
- 降水は,大気中の放射性核素を除去する重要なメカニズムとして機能することができます.
- 降水におけるSr-89/Sr-90比は,最近の核事象と大気輸送の動態についての洞察を提供します.
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