90Sr and 137Cs Contamination of Wheat Produced in Japan. Survey and Analysis during the Years 1959 through 1995 Including the Chernobyl Accident.:—Survey and Analysis during the Years 1959 through 1995 Including the Chernobyl Accident—
スポンサーリンク
概要
- 論文の詳細を見る
<I>This paper attempts to discuss the influences of global-scale radioactive fallout on wheat produced in Japan. For this purpose, a set of wheat samples was collected annually from sixteen National and Prefectural Experimental Farms during the years from 1959 to 1995</I>.<BR><I>According to the graph presenting year-to-year variations in the nationwide averages of</I> <SUP>90</SUP>Sr <I>and</I> <SUP>137</SUP>Cs <I>contents</I> (mBq/kg) <I>in wheat kernels, the sharp peak was first marked in 1963 with 12 300 for</I> <SUP>90</SUP>Sr <I>and 43600 for</I> <SUP>137</SUP>Cs. <I>In 1966, however, the nuclide contents dropped drastically to 2360 for</I> <SUP>90</SUP>Sr <I>and 2 870 for</I> <SUP>137</SUP>Cs <I>respectively. In the years following, both nuclides continued to decrease slowly although there were minor fluctuations</I>.<BR><I>It is noticeable that low-level</I> <SUP>137</SUP>Cs <I>contamination was caused in Japan's wheat in 1981, the year after the nuclear testing in China. It is also noticeable that</I> <SUP>137</SUP>Cs <I>contents in wheat kernels increased to 5960 in 1986 when the Chernobyl nuclear power plant accident happened, although it dropped back to its normal level of 40 in the year after</I>.<BR><I>The following are also discussed in this paper : (1) Year to year variations in the ratio of</I> <SUP>90</SUP>Sr <I>to</I> <SUP>137</SUP>Cs <I>contents in wheat kernels and wheat flour. (2) Regional differences in</I> <SUP>90</SUP>Sr <I>and</I> <SUP>137</SUP>Cs <I>contents in wheat kernels. (3) Comparison of</I> <SUP>90</SUP>Sr <I>and</I> <SUP>137</SUP>Cs <I>contents in wheat kernels and unpolished rice. (4) Direct and indirect pathways of</I> <SUP>90</SUP>Sr <I>and</I> <SUP>137</SUP>Cs <I>that contaminate wheat. (5) Influence of the Chernobyl power plant accident. (6) Suggestions about the ways of estimating the level of</I> <SUP>137</SUP>Cs <I>contamination in case of nuclear accidents, if any</I>.
- 社団法人 日本アイソトープ協会の論文
社団法人 日本アイソトープ協会 | 論文
- Distortion of Pulse Height Spectra Due to Absorbers in the Measurement of Low-energy .BETA.-rays with a Silicon Detector.
- タイトル無し
- Estimation of Angular Distributions of the Low-Energy .BETA.-Ray Emission from a Sealed Source.
- Comparison of SPECT images with four kinds of 99nTc collimators.
- Cross Talks on to 201Tl- and 123I-Photopeak Windows with Simultaneous Administration of Them, Using of a Gamma Camera.