Morphological reproductive characteristics of testes and fertilization capacity of cryopreserved sperm after the Fukushima accident in raccoon ()

Komatsu, Kazuki*; Iwasaki, Tsugumi*; Murata, Kosuke*; Yamashiro, Hideaki*; Goh, V. S. T.*; Nakayama, Ryo*; Fujishima, Yohei*; Ono, Takumi*; Kino, Yasushi*; Shimizu, Yoshinaka*; et al.

Reproduction in Domestic Animals, 56(3), p.484 - 497, 2021/03

https://doi.org/10.1111/rda.13887

We have established an archive system of livestock and wild animals from the surrounding ex-evacuation zone. Wildlife within the alert zone have been exposed to low-dose-rate (LDR) radiation for a long and continuous time. In this study, we analysed the morphological characteristics of the testes and in vitro fertilization (IVF) capacity of cryopreserved sperm of raccoons from the ex-evacuation zone of the FDNPP accident. This study revealed that the chronic and LDR radiation exposure associated with the FDNPP accident had no adverse effect on the reproductive characteristics and functions of male raccoons.

Spallation and fragmentation cross sections for 168 MeV/nucleon Xe ions on proton, deuteron, and carbon targets

Sun, X. H.*; Wang, H.*; Otsu, Hideaki*; Sakurai, Hiroyoshi*; Ahn, D. S.*; Aikawa, Masayuki*; Fukuda, Naoki*; Isobe, Tadaaki*; Kawakami, Shunsuke*; Koyama, Shumpei*; et al.

Physical Review C, 101(6), p.064623_1 - 064623_12, 2020/06

https://doi.org/10.1103/PhysRevC.101.064623

The spallation and fragmentation reactions of Xe induced by proton, deuteron and carbon at 168 MeV/nucleon were studied at RIKEN Radioactive Isotope Beam Factory via the inverse kinematics technique. The cross sections of the lighter products are larger in the carbon-induced reactions due to the higher total kinetic energy of carbon. The energy dependence was investigated by comparing the newly obtained data with previous results obtained at higher reaction energies. The experimental data were compared with the results of SPACS, EPAX, PHITS and DEURACS calculations. These data serve as benchmarks for the model calculations.

Experimental determination of the topological phase diagram in Cerium monopnictides

Kuroda, Kenta*; Ochi, Masayuki*; Suzuki, Hiroyuki*; Hirayama, Motoaki*; Nakayama, Mitsuhiro*; Noguchi, Ryo*; Bareille, C.*; Akebi, Shuntaro*; Kunisada, So*; Muro, Takayuki*; et al.

Physical Review Letters, 120(8), p.086402_1 - 086402_6, 2018/02

https://doi.org/10.1103/PhysRevLett.120.086402

Synthesized research report in the second mid-term research phase; Mizunami Underground Research Laboratory Project, Horonobe Underground Research Laboratory Project and Geo-stability Project

Hama, Katsuhiro; Mizuno, Takashi; Sasao, Eiji; Iwatsuki, Teruki; Saegusa, Hiromitsu; Sato, Toshinori; Fujita, Tomoo; Sasamoto, Hiroshi; Matsuoka, Toshiyuki; Yokota, Hideharu; et al.

JAEA-Research 2015-007, 269 Pages, 2015/08

JAEA-Research-2015-007.pdf:68.65MB
JAEA-Research-2015-007(errata).pdf:0.07MB

We have synthesised the research results from Mizunami/Horonobe URLs and geo-stability projects in the second mid-term research phase. It could be used as technical bases for NUMO/Regulator in each decision point from sitting to beginning of disposal (Principal Investigation to Detailed Investigation Phase). High quality construction techniques and field investigation methods have been developed and implemented and these will be directly applicable to the National Disposal Program (along with general assessments of hazardous natural events and processes). It will be crucial to acquire technical knowledge on decisions of partial backfilling and final closure by actual field experiments in Mizunami/Horonobe URLs as main themes for the next phases.

Spin mixing conductance at a well-controlled platinum/yttrium iron garnet interface

Qiu, Z.*; Ando, Kazuya*; Uchida, Kenichi*; Kajiwara, Yosuke*; Takahashi, Ryo*; Nakayama, Hiroyasu*; An, Toshu*; Fujikawa, Yasunori*; Saito, Eiji

Applied Physics Letters, 103(9), p.092404_1 - 092404_4, 2013/08

https://doi.org/10.1063/1.4819460

A platinum (Pt)/yttrium iron garnet (YIG) bilayer system with a well-controlled interface has been developed; spin mixing conductance at the Pt/YIG interface has been studied. A clear interface with good crystal perfection is experimentally demonstrated to be one of the important factors for an ultimate spin mixing conductance. The spin mixing conductance is obtained to be 1.310m at the well-controlled Pt/YIG interface, which is close to a theoretical prediction.

Decontamination of outdoor school swimming pools in Fukushima after the nuclear accident in March 2011

Saegusa, Jun; Kurikami, Hiroshi; Yasuda, Ryo; Kurihara, Kazuo; Arai, Shigeki; Kuroki, Ryota; Matsuhashi, Shimpei; Ozawa, Takashi; Goto, Hiroaki; Takano, Takao; et al.

Health Physics, 104(3), p.243 - 250, 2013/03

https://doi.org/10.1097/HP.0b013e318277b3ee

After the Nuclear accident on March 2011, water discharge from many outdoor swimming pools in the Fukushima prefecture was suspended out of concern that radiocesium in the pool water would flow into farmlands. We have reviewed the existing flocculation method for decontaminating pool water and established a practical decontamination method by demonstrating the process at several pools in the Fukushima prefecture.

R&D of removal technology of radioactive contaminants from the environment by using polymer absorbents

Ito, Hisayoshi; Seko, Noriaki; Kuroki, Ryota; Yaita, Tsuyoshi; Naganawa, Hirochika; Nakayama, Shinichi

Hoshasen Kagaku (Internet), (93), p.31 - 36, 2012/03

For removing radioactive contaminants from the environment due to the nuclear plant accident, we have synthesized highly efficient cesium absorbents by introducing molybdophosphoric acid groups into polyethylene matrix with radiation grafting. Cesium absorbents based on protein or crown ether materials have been newly developed. We have also established immobilization-collection technology of cesium-adsorbed surface soil by using a mixture of polyion and bentonitic clay material. The effectiveness of these materials has been demonstrated through the field examination in Fukushima.

Environmental clean-up projects of JAEA, developments for recovery and decontamination methods of radioactive materials by the polymer-like compounds, 1; Environmental clean-up project of JAEA

Nakayama, Shinichi; Ito, Hisayoshi; Matsuhashi, Shimpei; Kuroki, Ryota; Suzuki, Shinichi; Seko, Noriaki; Yaita, Tsuyoshi

no journal, , 

no abstracts in English

The Training for young educators to learn the correct understanding about handling of radioactive materials and radiation

Usui, Toshihide; Nakayama, Naoto; Iwasa, Atsutoshi; Miura, Yoshiyuki; Ishida, Keiichi; Irokawa, Hiroyuki; Hamazaki, Masaaki; Okawa, Yasuhisa; Iwai, Ryo

no journal, , 

no abstracts in English

Verification of removal technology of radioactive contaminants from the environment by using polymer adsorbents

Ito, Hisayoshi; Seko, Noriaki; Kuroki, Ryota; Yaita, Tsuyoshi; Naganawa, Hirochika; Nakayama, Shinichi

no journal, , 

For developing the removal technology of radioactive contaminants from the environment, we have performed R&D of superior cesium adsorbents. As a result, we have synthesized highly efficient cesium adsorbents by introducing molybdophosphoric acid groups into polyethylene matrix with radiation grafting. We have designed and prepared several mutant proteins with high cesium affinity, which are appropriate for cesium adsorbents. Adsorbents based on dibenzo-20-crown 6-ether (DB20C6) with high cesium selectivity have been also developed. Furthermore, we have developed immobilization-collection technology of cesium-adsorbed surface soil by using synergetic functions of polyion and bentonitic clay. The effectiveness of the decontamination technology newly developed has been verified through the field tests in Iitate-mura, Fukushima.