Contribution to risk reduction in decommissioning works by the elucidation of basic property of radioactive microparticles (Contract research); FY2018 Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development

Collaborative Laboratories for Advanced Decommissioning Science; Ibaraki University*

JAEA-Review 2019-041, 71 Pages, 2020/03

JAEA-Review-2019-041.pdf:3.38MB

JAEA/CLADS, has been conducting the Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development (hereafter referred to "the Project") since FY2018. The Project aims at solving problems in nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. For this purpose, intelligence has been collected from all over the world, and basic research and human resource development have been promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. Among the adopted proposals in FY2018, this report summarizes the research results of the "Contribution to Risk Reduction in Decommissioning Works by the Elucidation of Basic Property of Radioactive Microparticles". In order to establish the decommissioning procedures (recovery of the melted fuels, decontamination inside the reactors, ensuring the safety of the workers, etc.) of the Fukushima Daiichi Nuclear Power Station, radioactive microparticles released by the accident are an important information source for clarifying what had happened inside the reactors in the course of the accident. The purpose of the present study is to obtain detailed knowledge on the basic properties (particle size, composition, electrical/optical properties, etc.) of the radioactive microparticles, as well as to further elucidate the various properties of the radioactive microparticles including the quantitative evaluation of alpha-ray-emitters, through the Japan-UK synergetic research. Thus, we are conducting research and development that will contribute to the comprehensive works towards the risk reduction in the "decommissioning" plan.

Development of frequency stabilized laser system for long-lived isotope analysis, 1; Development of Littrow configuration extended cavity diode laser

Miyabe, Masabumi; Oda, Koichi*; Oba, Masaki; Kato, Masaaki; Wakaida, Ikuo; Watanabe, Kazuo

JAERI-Tech 2004-064, 33 Pages, 2004/10

JAERI-Tech-2004-064.pdf:1.89MB

In nuclear waste materials there are various radionuclides to which standard analytical techniques are difficult to be applied. We are developing an analytical technique where such nuclides are analyzed using multi-step resonance ionization mass spectrometry. In this study, we have developed an external cavity diode laser applicable to the analysis. The wavelength and output power dependence on injection current and temperature were investigated for various types of laser diodes. Based on the data, we have obtained a suitable condition to operate the ECDL in stable single-mode oscillation, so that a continuous scanning range of about 100 GHz was realized. Additionaly, to evaluate the bandwidth of the developed ECDL, we have performed Doppler-free spectroscopy. The reasonable agreement of the measured isotope shift and HFS splitting with the reported values demonstrated that the developed ECDL is applicable to a precise laser spectroscopy as well as a laser trace analysis.

Proceedings of the Colloquium on Ultra-trace Analysis of Environmental Samples; 28 Nov. 2001, JAERI, Tokai, Japan

Takai, Konomi; Sakurai, Satoshi; Usuda, Shigekazu; Watanabe, Kazuo

JAERI-Conf 2002-002, 98 Pages, 2002/03

JAERI-Conf-2002-002.pdf:4.66MB

The Colloquium on Ultra-trace Analysis of Environmental Samples was held on November 28, 2001 at CLEAR (Clean Laboratory for Environmental Analysis and Research) located at JAERI Tokai Establishment. Eight presentations were made at the colloquium, covering wide area of the relevant works such as development of analytical technology, environmental sample analysis and application to the safeguards. Each presentation was followed by animated discussion. This report assembles the full papers for the presentations reported at the colloquium.

Estimation of longitudinal and transverse dispersivities in the Twin Lake natural gradient tracer tests

Takeda, Seiji; Moltyaner, G. L.*

JAERI-Research 98-031, 28 Pages, 1998/06

JAERI-Research-98-031.pdf:1.29MB

no abstracts in English

Intra-organic change of trace elements in fetal development; Measurement by neutron activation analysis

Shin, Sumio*; Sato, Kiichi*; Nishida, Hiroshi*; Sakamoto, Shoichi*; Yamabayashi, Hisamichi; Motoki, Ryozo; Terunuma, Kusuo; Yamamoto, Takeo

Igaku No Ayumi, 140(1), p.51 - 52, 1987/01

Trace elements serve as key components of enzyme systems and have especially important correlation with fetal maturity.