New development of study on atmospheric transport processes of environmental radioactivity

• Project/Area Number: 24360392
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Nuclear engineering
• Research Institution: Nagoya University
• Principal Investigator: YAMAZAWA Hiromi 名古屋大学, 工学(系)研究科(研究院), 教授 (70345916)
• Co-Investigator(Kenkyū-buntansha): MORIIZUMI Jun 名古屋大学, 大学院工学研究科, 准教授 (90303677) ; HIRAO Shigekazu 名古屋大学, 大学院工学研究科, 助教 (30596060)
• Research Collaborator: HIROUCHI Jun ; LIU Heng ; KONDO Daisuke
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥9,360,000 (Direct Cost: ¥7,200,000、Indirect Cost: ¥2,160,000); Fiscal Year 2014: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2012: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000)
• Keywords: 放射性核種 / ラドン壊変生成物 / 湿性沈着 / 洗浄係数 / 降水中濃度 / 空間線量率 / 地面上濃度推定 / 放射性核種濃度 / 除去効率 / モデル化 / 放射性核種沈着 / 環境放射線モニタリング

Outline of Final Research Achievements

A series of measurements were carried out for concentrations of radon decay products in rain water with a high time resolution. Temporal variations in the measured concentration, which followed the variation in rain intensity, were analyzed to formulate the washout coefficient of air-borne radionuclides as a function of rain intensity. It was demonstrated that the temporal variations in concentration in rain water were reproduced with a very high accuracy by using the proposed formula.
Methods for estimating surface concentrations of deposited radionuclides from temporal change in dose rate and from gamma-ray spectral information provided from monitoring installations were developed.

Research Products

• [Journal Article] Estimation of surface concentration of radon decay products from gamma dose rate change after rain (2014)
  • Author(s): J.Hirouchi, S. Hirao, J. Moriizumi, H. Yamazawa, A. Suzuki
  • Journal Title: Progress in Nuclear Science and Technology Volume: 4 Pages: 871-874
  • DOI: 10.15669/pnst.4.871
  • ISSN: 2185-4823
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] ON THE CHARACTERISTICS OF THE WET DEPOSITION PROCESS USING RADON AS ATRACER GAS (2014)
  • Author(s): Heng Liu*, Kondo Daisuke, Matsuda Motokiyo, Shigekazu Hirao, Jun Moriizumi and Hiromi Yamazawa
  • Journal Title: Radiation Protection Dosimetry Volume: 160 Issue: 1-3 Pages: 83-86
  • DOI: 10.1093/rpd/ncu093
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Estimation of infiltration and surface run-off characteristics of radionuclides from gamma (2014)
  • Author(s): Jun Hirouchi, Shigekazu Hirao, Jun Moriizumi, Hiromi Yamazawa and Atsuo Suzuki
  • Journal Title: Journal of Nuclear Science and Technology Volume: 51 Issue: 1 Pages: 48-55
  • DOI: 10.1080/00223131.2014.847808
  • Peer Reviewed
• [Journal Article] ESTIMATION OF SURFACE CONCENTRATION OF RADON DECAY PRODUCTS FROM GAMMA DOSE RATE CHANGE AFTER RAIN (2013)
  • Author(s): Jun Hirouchi, Shigekazu Hirao, Jun Moriizumi, Hiromi Yamazawa
  • Journal Title: Progress in Nuclear Science and Technology Volume: (in press)(掲載決定)
  • Peer Reviewed
• [Presentation] 御前崎半島での地上ラドン濃度観測とラドン長距離輸送モデルによる再現 (2015)
  • Author(s): 浅野恵史、廣内 淳、平尾茂一、森泉 純、山澤弘実
  • Organizer: 第16回「環境放射能」研究会
  • Place of Presentation: 筑波
  • Year and Date: 2015-03-09 – 2015-03-11
• [Presentation] ラドン長距離輸送モデルの冬期東アジア域における濃度過小評価の要因検討 (2015)
  • Author(s): 杉浦宏樹、平尾茂一、森泉 純、山澤弘実、田阪茂樹
  • Organizer: 第16回「環境放射能」研究会
  • Place of Presentation: 筑波
  • Year and Date: 2015-03-09 – 2015-03-11
• [Presentation] 雨水中ラドン壊変生成物濃度の測定と沈着モデルによる計算 (2014)
  • Author(s): 坂田慶介、劉コウ;、平尾茂一、森泉 純、山澤弘実
  • Organizer: 第46回日本原子力学会中部支部研究発表会
  • Place of Presentation: 名古屋
  • Year and Date: 2014-12-17 – 2014-12-18
• [Presentation] Effect of Geometric Structure around Detector and Infiltration of Radionuclides on Radioactivity Concentration Estimation from NaI(Tl) Pulse Height Distribution (2014)
  • Author(s): J. Hirouchi, Y. Terasaka, S. Hirao, J. Moriizumi and H. Yamazawa
  • Organizer: The 9th International Symposium on the Natural Radiation Environment(NRE-IX)
  • Place of Presentation: Hirosaki
  • Year and Date: 2014-09-23 – 2014-09-26
• [Presentation] Bi-214/Pb-214 Activity Radio in Rainwater for Residence time Estimation of Cloud Droplets and Raindrops (2014)
  • Author(s): J. Moriizumi D.Kondo, Y. Kojima, H. Liu, S. Hirao and H. Yamazawa
  • Organizer: The 9th International Symposium on the Natural Radiation Environment(NRE-IX)
  • Place of Presentation: Hirosaki
  • Year and Date: 2014-09-23 – 2014-09-26
• [Presentation] Inverse Estimation of Radio Flux Distribution for East Asia Using Measured Atmospheric Radon Concentration (2014)
  • Author(s): S. Hirao, R. Hayashi, J. Moriizumi, H. Yamazawa, Y. Tohjima and H. Mukai
  • Organizer: The 9th International Symposium on the Natural Radiation Environment(NRE-IX)
  • Place of Presentation: Hirosaki
  • Year and Date: 2014-09-23 – 2014-09-26
• [Presentation] NaI(TI)検出器で測定された波高分布の解析による地面上放射能濃度の推定(2)浸透が濃度推定に与える影響 (2014)
  • Author(s): 廣内 淳、寺阪裕太、平尾茂一、森泉 純、山澤弘実
  • Organizer: 日本原子力学会「2014年春の年会」
  • Place of Presentation: 東京
• [Presentation] NaI(TI)検出器で測定された波高分布の解析による地面上放射能濃度の推定(1)検出器周辺の幾何学的構造が濃度推定に与える影響 (2014)
  • Author(s): [14] 寺阪裕太、廣内 淳、平尾茂一、森泉 純、山澤弘実
  • Organizer: 日本原子力学会「2014年春の年会」
  • Place of Presentation: 東京
• [Presentation] Estimation of Surface Concentration of Radon Decay Products from Gamma Dose Rate Change after Rain (2013)
  • Author(s): [1] J. Hirouchi, S. Hirao, J. Moriizumi, A. Suzuki and H. Yamazawa
  • Organizer: 2013 ANS Winter Meeting
  • Place of Presentation: Washington DC, U.S.A.
  • Invited
• [Presentation] On the Characteristics of Wet Deposition Process Using Radon as Tracer Gas (2013)
  • Author(s): H. Liu, J. Moriizumi and Y. Yamazawa
  • Organizer: 7th Conference on Protection against Radon at Home and at Work (Radon2013)
  • Place of Presentation: Prague
• [Presentation] 波照間島起源ラドンの大気中ラドン濃度観測値に対する寄与の推定 (2013)
  • Author(s): 林 亮介、平尾茂一、森泉 純、山澤弘実
  • Organizer: 日本原子力学会「2013年秋の年会」
  • Place of Presentation: 八戸
• [Presentation] Deduction of Useful Information from Dose Rate Monitoring Data in an Emergency (2012)
  • Author(s): J. Hirouchi, T. Zhang, Y. Takamura, S. Hirao, J. Moriizumi, H. Yamazawa
  • Organizer: International Symposium on Environmental Monitoring and Dose Estimation of Residents after Accident of TEPCO's Fukushima Daiichi Nuclear Power Station
  • Place of Presentation: 京都
  • Year and Date: 2012-12-14
• [Presentation] 降雨後の空間カンマ線線量率変動の解析による放射性核種の浸透特性の推定 (2012)
  • Author(s): 廣内淳, 平尾茂一, 森泉 純, 山澤弘実
  • Organizer: 日本原子力学会「2012年秋の大会」
  • Place of Presentation: 広島
  • Year and Date: 2012-09-19
• [Presentation] 雨水中21Bi/214Pb放射能比による雲粒・雨粒の存在時間の推定 (2012)
  • Author(s): 近藤大祐, 劉絎,森泉 純, 平尾茂一, 山澤弘実
  • Organizer: 日本原子力学会「2012年秋の大会」
  • Place of Presentation: 広島
  • Year and Date: 2012-09-19
• [Presentation] Estimation of surface concentration of radon decay products from gamma dose rate change after rain (2012)
  • Author(s): Jun Hirouchi, Shigekazu Hirao, Jun Moriizumi, Hiromi Yamazawa
  • Organizer: 12^<th> International Conference on Radiation Shielding
  • Place of Presentation: 奈良
  • Year and Date: 2012-09-07
• [Presentation] Atmospheric Dispersion of Radioactive Materials Discharged from Fukushima Daiichi Nuclear Power Station (2012)
  • Author(s): H. Yamazawa, S. Hirao
  • Organizer: 12^<th> International Conference on Radiation Shielding
  • Place of Presentation: 奈良(招待講演)
  • Year and Date: 2012-09-02