著者
坂本 文徳 大貫 敏彦 香西 直文 五十嵐 翔祐 山崎 信哉 吉田 善行 田中 俊一
出版者
Atomic Energy Society of Japan
雑誌
日本原子力学会和文論文誌 (ISSN:13472879)
巻号頁・発行日
pp.1111290030, (Released:2011-11-30)
参考文献数
12
被引用文献数
8 10

The environmental behavior of radioactive Cs in the fallout from the accident of the Fukushima Daiichi Nuclear Power Plant has been studied by measuring its spatial distribution on/in trees, plants, and surface soil beneath the plants using autoradiography analysis. The results of autoradiography analysis showed that radioactive Cs was distributed on the branches and leaves of trees that were present during the accident and that only a small fraction of radioactive Cs was transported to new branches and leaves grown after the accident. Radioactive Cs was present on the grass and rice stubble on the soils, but not in the soils beneath the grass and rice stubble, indicating that the radioactive Cs was deposited on the grass and the rice plant. In addition, the ratio of the radioactive Cs that penetrated into the soil layer by weathering was very small two months after the accident. These results indicate that trees and other plants are the reservoir of the fallout Cs and function to retard the fallout Cs migration with rain water.
著者
徳永 紘平 高橋 嘉夫 香西 直文
出版者
一般社団法人日本地球化学会
雑誌
日本地球化学会年会要旨集 2019年度日本地球化学会第66回年会講演要旨集
巻号頁・発行日
pp.193, 2019 (Released:2019-11-20)

福島第一原子力発電所事故によって放出された放射性ストロンチウム(Sr)は、海水中の他の元素の影響を受けやすいため従来の鉱物や樹脂を用いた処理が難しく、福島の海水を含む汚染水からの有効な除去技術は未だ開発されていない。本研究では、これら多種の放射性核種に対する新規の除去法として、バライト構造の一部をカルシウム(Ca) などの不純物で置換させ、結晶構造に不安定性を与えたバライト試料(Ca部分置換のバライト試料)を利用した、放射性Srの新しい固定化法の開発を行った。
著者
坂本 文徳 大貫 敏彦 香西 直文 五十嵐 翔祐 山崎 信哉 吉田 善行 田中 俊一
出版者
Atomic Energy Society of Japan
雑誌
日本原子力学会和文論文誌 (ISSN:13472879)
巻号頁・発行日
vol.11, no.1, pp.1-7, 2012 (Released:2012-02-15)
参考文献数
12
被引用文献数
8 10

The environmental behavior of radioactive Cs in the fallout from the accident of the Fukushima Daiichi Nuclear Power Plant has been studied by measuring its spatial distribution on/in trees, plants, and surface soil beneath the plants using autoradiography analysis. The results of autoradiography analysis showed that radioactive Cs was distributed on the branches and leaves of trees that were present during the accident and that only a small fraction of radioactive Cs was transported to new branches and leaves grown after the accident. Radioactive Cs was present on the grass and rice stubble on the soils, but not in the soils beneath the grass and rice stubble, indicating that the radioactive Cs was deposited on the grass and the rice plant. In addition, the ratio of the radioactive Cs that penetrated into the soil layer by weathering was very small two months after the accident. These results indicate that trees and other plants are the reservoir of the fallout Cs and function to retard the fallout Cs migration with rain water.
著者
木村 建貴 香西 直文 坂本 文徳 福谷 哲 池上 麻衣子
出版者
公益社団法人 土木学会
雑誌
土木学会論文集G(環境) (ISSN:21856648)
巻号頁・発行日
vol.76, no.7, pp.III_375-III_382, 2020 (Released:2021-03-17)
参考文献数
20

粘土鉱物に吸着したセシウムの一部が微生物の作用により溶出することが明らかになってきている.一般的に植物は微生物と共生関係を築くが,粘土鉱物からのセシウム溶出に係る植物と微生物間における相乗効果は報告されていない.本研究では,植物由来の有機酸に着目し,まず植物(シロツメクサ)が生産する有機酸分析を行った.次に,シロツメクサ由来として同定された乳酸を用いて,微生物の培養実験を黒雲母存在下で行った.その結果,増殖の誘導期において黒雲母から溶出した鉄等の量が乳酸の添加により増大した.また,セシウムを吸着させた黒雲母からセシウムが溶出した.これは黒雲母が部分的に溶解したことに伴い吸着していたセシウムが溶出したと考えられる.また,溶出したセシウムは,増殖した微生物に吸収されたことが示唆される.
著者
坂本 文徳 大貫 敏彦 香西 直文 山崎 信哉 吉田 善行 難波 謙二
出版者
一般社団法人 日本原子力学会
雑誌
日本原子力学会和文論文誌 (ISSN:13472879)
巻号頁・発行日
pp.J13.002, (Released:2013-10-10)
参考文献数
20
被引用文献数
4 5

The local area distribution and relocation of radioactive cesium deposited in trees after the 2011 tsunami-related accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) have been studied by measuring the spatial distribution of cesium on/in trees by autoradiography analysis. Samples of trees were collected from places located between 4 and 55 km from FDNPP approximately 2, 8, 20, and 22 months after the accident. The autoradiography analyses of Cryptomeria japonica, Torreya nucifera, and Thujopsis dolabrata var. hondae samples collected approximately 2 and 8 months after the accident showed that radioactive Cs was mainly distributed as spots on the branches and leaves of the trees emerged before the accident, and was detected in negligible amounts in new branch and leaves that emerged after the accident. On the contrary, radioactive Cs was detected at the outermost tip of the branches in the trees collected 20 months after the accident. Morus alba samples collected 22 months after the accident contained radioactive Cs inside and outside their stems, even though no radioactive Cs was detected in their roots, strongly suggesting that a certain amount of radioactive Cs was translocated from the outside to the inside of stems. These results indicate that the distribution of radioactive Cs deposited on/in the trees gradually changes with time (scale: year).
著者
坂本 文徳 香西 直文 鈴木 義規
出版者
独立行政法人日本原子力研究開発機構
雑誌
基盤研究(C)
巻号頁・発行日
2009

ウランを特異的に集めるタンパク質を効率的に特定する新規の手法を開発した。この方法は、サイズ排除カラムを利用した液体クロマトグラフィーと質量分析器を組み合わせた検出系を利用している。実際に、この方法を利用して、酵母タンパク質からウランを集めるタンパク質特定を試みたところ、46キロダルトン程度の大きさのタンパク質がウランを集めることを明らかにした。そして、そのタンパク質は硫黄を含むアミノ酸(メチオニンとシステイン)を構成要素としないことが示唆された。
著者
坂本 文徳 大貫 敏彦 香西 直文 山崎 信哉 吉田 善行 難波 謙二
出版者
Atomic Energy Society of Japan
雑誌
日本原子力学会和文論文誌 (ISSN:13472879)
巻号頁・発行日
vol.12, no.4, pp.257-266, 2013
被引用文献数
5

The local area distribution and relocation of radioactive cesium deposited in trees after the 2011 tsunami-related accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) have been studied by measuring the spatial distribution of cesium on/in trees by autoradiography analysis. Samples of trees were collected from places located between 4 and 55 km from FDNPP approximately 2, 8, 20, and 22 months after the accident. The autoradiography analyses of <i>Cryptomeria japonica</i>, <i>Torreya nucifera</i>, and <i>Thujopsis dolabrata</i> var. <i>hondae</i> samples collected approximately 2 and 8 months after the accident showed that radioactive Cs was mainly distributed as spots on the branches and leaves of the trees emerged before the accident, and was detected in negligible amounts in new branch and leaves that emerged after the accident. On the contrary, radioactive Cs was detected at the outermost tip of the branches in the trees collected 20 months after the accident. <i>Morus alba</i> samples collected 22 months after the accident contained radioactive Cs inside and outside their stems, even though no radioactive Cs was detected in their roots, strongly suggesting that a certain amount of radioactive Cs was translocated from the outside to the inside of stems. These results indicate that the distribution of radioactive Cs deposited on/in the trees gradually changes with time (scale: year).<br>
著者
坂本 文徳 大貫 敏彦 香西 直文 山崎 信哉 吉田 善行 難波 謙二
出版者
一般社団法人 日本原子力学会
雑誌
日本原子力学会和文論文誌 (ISSN:13472879)
巻号頁・発行日
vol.12, no.4, pp.257-266, 2013 (Released:2013-11-15)
参考文献数
20
被引用文献数
4 5

The local area distribution and relocation of radioactive cesium deposited in trees after the 2011 tsunami-related accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) have been studied by measuring the spatial distribution of cesium on/in trees by autoradiography analysis. Samples of trees were collected from places located between 4 and 55 km from FDNPP approximately 2, 8, 20, and 22 months after the accident. The autoradiography analyses of Cryptomeria japonica, Torreya nucifera, and Thujopsis dolabrata var. hondae samples collected approximately 2 and 8 months after the accident showed that radioactive Cs was mainly distributed as spots on the branches and leaves of the trees emerged before the accident, and was detected in negligible amounts in new branch and leaves that emerged after the accident. On the contrary, radioactive Cs was detected at the outermost tip of the branches in the trees collected 20 months after the accident. Morus alba samples collected 22 months after the accident contained radioactive Cs inside and outside their stems, even though no radioactive Cs was detected in their roots, strongly suggesting that a certain amount of radioactive Cs was translocated from the outside to the inside of stems. These results indicate that the distribution of radioactive Cs deposited on/in the trees gradually changes with time (scale: year).