Radiation measurements at the campus of Fukushima Medical University through the 2011 off the Pacific Coast of Tohoku earthquake and subsequent nuclear power plant crisis
スポンサーリンク
概要
- 論文の詳細を見る
An earthquake, Tohoku region Pacific Coast earthquake, occurred on the 11th of March, 2011, and subsequent Fukushima nuclear power plant accidents have been stirring natural radiation around the author's office in Fukushima Medical University (FMU). FMU is located in Fukushima city, and is 57 km (35 miles) away from northwest of the Fukushima Daiichi nuclear power plant. This paper presents three types of radiation survey undertaken through the unprecedented accidents at the campus and the hospital of FMU. First, a group of interested people immediately began radiation surveillance; the group members were assembled from the faculty members of " Life Sciences and Social Medicine" and " Human and Natural Sciences." Second, the present author, regardless of the earthquake, had serially observed natural radiations such as gamma radiation in air with NaI scintillation counter, atmospheric radon with Lucas cell, and second cosmic rays with NaI scintillation. Gamma radiation indicated most drastic change, i.e., peak value (9.3 times usual level) appeared on March 16, and decreased to 1.7 times usual level after two months. A nonlinear least squares regression to this decreasing data gave short half-life of 3.6 days and long half-life of 181 days. These two apparent half-lives are attributed to two groups of radioisotopes, i.e., short half-life one of I-131 and long half-life ones of Cs-134, Cs-137 and Sr-90. Also, atmospheric radon concentration became high since a stop of ventilation, while second cosmic rays did not show any response. Third, late April, 2011, a team of radiation dosimetry under the direct control of Dean, School of Medicine, was established for the continuation of radiation survey in the campus and the hospital of Fukushima Medical University.
論文 | ランダム
- Introduccion sociocultural a la historia de Espana-2-
- 養豚農家と道都圏生協の産直運動--茨城・境食肉センタ- (食肉の流通)
- 甫足家蔵「百人一首抄」
- 肥後藩歌壇の研究(1)
- 文化の伝播と変容 : 文化科学における北海道の地位について