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Maurer, C.*; Galmarini, S.*; Solazzo, E.*; Ku
mierczyk-Michulec, J.*; Bar
, J.*; Kalinowski, M.*; Schoeppner, M.*; Bourgouin, P.*; Crawford, A.*; Stein, A.*; et al.
Journal of Environmental Radioactivity, 255, p.106968_1 - 106968_27, 2022/12
被引用回数:9 パーセンタイル:43.51(Environmental Sciences)2015, 2016年のモデル比較演習を経て、2019年に包括的なXe-133大気輸送モデル比較試験を企画した。欧米の医療用RI製造施設であるIREやCNLからの排出の影響が大きいヨーロッパと北米にある4つのCTBT国際モニタリングシステム局を対象とし、約30の参加モデルの結果の比較とアンサンブルを実施した。第2回ATMチャレンジの教訓により、参加者は事務局の指定する条件に基づいて計算を実施した。その結果、IREとCNLからの正確な日別スタック排出量を使用しても、拡散過程における誤差、残存排出源の適切な特性化、長いIMSサンプリング時間(12
24時間)のデメリットと相殺され、平均すればスコアの改善が見られないことが確認された。一方、任意のモデル計算結果を用いたアンサンブルを実施したところ、今回対象とした4つの観測所でのXe-133バックグラウンドを十分に予測できることが確認できた。有効なアンサンブルのサイズは5以下であった。
Xia, C.-J.*; 丸山 敏毅; Li, A.*; Sun, B. Y.*; Long, W.-H.*; Zhang, Y.-X.*
Communications in Theoretical Physics, 74(9), p.095303_1 - 095303_15, 2022/08
被引用回数:34 パーセンタイル:92.03(Physics, Multidisciplinary)In the framework of the Thomas-Fermi approximation, we study the EOSs and microscopic structures of neutron star matter in a vast density range with
-
, where various covarriant density functionals are adopted, i.e., those with nonlinear self couplings (NL3, PK1, TM1, GM1,MTVTC) and density-dependent couprings (DD-LZ1, DDME-X, PKDD, DD-ME2, DD2, TW99)It is found that the EOSs generally coincide with each other at
fm
and
fm
fm
, while in other density regions they are sensitive to the effective interactions between nucleons. By adopting functionals with a larger slope of symmetry energy
the curvature parameter
and neutron drip density generally increases, while the droplet size, proton number of nucleus, core-crust transition density and onset density of non-spherical nuclei, decrease. All functionals predict neutron stars, with maximum masses exceeding the two-solar-mass limit, while those of DD2, DD-LZ2, DD-ME2, and DDME-X predict optimum neutron star radii according to the observational constraints. Nevertheless, the corresponding skewness coefficients
are much larger than expected, while only the functionals MTVTC and TW99 meet the start-of-art constraints on
. More accurate measurements on the radius of PSR J0740+6620 and the maximum mass of neutron stars are thus essential to identify the functional that satisfies all constraints from nuclear physics and astrophysical observations. Approximate linear correlations between neutron stars' radii at
and
, the slope
and curvature parameter
of symmetry energy are adopted here. The results presented here are applicable for investigations of the structures and evolutions of compact stars in a unified manner.
Xia, C.-J.*; Sun, B. Y.*; 丸山 敏毅; Long, W.-H.*; Li, A.*
Physical Review C, 105(4), p.045803_1 - 045803_14, 2022/04
被引用回数:23 パーセンタイル:92.72(Physics, Nuclear)Assuming spherical and cylindrical approximations for the Wigner-Seitz cell, typical nuclear matter structures (droplet, rod, slab, tube, bubble, and uniform) are observed. We then investigate the equations of state and microscopic structures of nuclear matter with both fixed proton fractions and beta equilibration, where two covariant density functionals, DD-LZ1 and DD-ME2, are adopted. Despite the smaller slope
of symmetry energy obtained with the functional DD-LZ1, the curvature parameter
is much larger than that of DD-ME2. Consequently, different mass-radius relations of neutron stars are predicted by the two functionals. Different microscopic structures of non-uniform nuclear matter are obtained as well, which are expected to affect various physical processes in neutron star properties and evolutions.
Passerini, S.*; Carardi, C.*; Grandy, C.*; Azpitarte, O. E.*; Chocron, M.*; Japas, M. L.*; Bubelis, E.*; Perez-Martin, S.*; Jayaraj, S.*; Roelofs, F.*; et al.
Proceedings of 2015 International Congress on Advances in Nuclear Power Plants (ICAPP 2015) (CD-ROM), p.780 - 790, 2015/05
The IAEA recently established a CRP on "Sodium properties and safe operation of experimental facilities in support of the development and deployment of Sodium Cooled Fast Reactors - NAPRO", to be carried out in the period 2013 - 2017. The first phase of the CRP is focused on the collection and assessment of sodium properties, and it will lead to a consistent property data set which will be published in the form of a handbook. This work is carried out by the 11 participating organizations from 10 Member States through the review and evaluation of the existing available data, the identification of the data gaps and the development of recommendations for experimental programmes to support closing these data gaps. A specific work package (WP 1.1), under the leadership of Argonne National Laboratory, is focused on the analysis of physical properties of sodium: thermodynamic properties and transport properties. The expected outcome includes the improved understanding of the availability, accuracy and range of applications of sodium properties centered on fast reactors and other technological applications. The implemented methodology for WP 1.1 is described and so the properties included in WP 1.1 and their classification. Major findings to date related to WP 1.1 are presented in this work, including detailed analysis of two selected properties.
Monti, S.*; Latge, C.*; Long, B.*; Azpitarte, O. E.*; Chellapandi, P.*; Stieglitz, R.*; Eckert, S.*; 大平 博昭; Lee, J.*; Roelofs, F.*; et al.
Proceedings of 2014 International Congress on the Advances in Nuclear Power Plants (ICAPP 2014) (CD-ROM), p.474 - 481, 2014/04
In order to address some inconsistencies regarding sodium physical and chemical properties, and internationally agreed standard rules for designing sodium experimental facilities, good practices and safety guidelines, the IAEA recently established a CRP on "Sodium properties and safe operation of experimental facilities in support of the development and deployment of Sodium Cooled Fast Reactors - NAPRO", to be carried out in the period 2013 - 2017. The CRP will be focused on the collection and assessment of sodium properties, and it will lead to a consistent property data set which will be published in the form of a handbook. This work will be carried out by the 11 participating organizations from 10 Member States through the review and evaluation of the existing available data, the identification of the data gaps and the development of recommendations for experimental programmes to support closing these data gaps. The CRP will also focus on the definition of design rules and best practice for sodium experimental facilities and guidelines for the safe handling of sodium, which poses hazard due to its chemical reactivity with water and air. Outcomes of this part of the CRP will include shared functional requirements, good practices, codes and standards and safety criteria for the design, construction and operation of experimental Na loops in support of innovative SFR.
Pewlong, W.*; Sudatis, B.*; 竹下 英文; 吉井 文男; 久米 民和
食品照射, 35(1-2), p.54 - 58, 2000/09
絹タンパク質は優れた生理学的な特性を有しており、新しい機能材料としての利用開発が期待されている。そこで、環境汚染防止及び資源のリサイクルに役立てることを目的に、絹タンパク質の放射線加工処理による改質効果に関する検討を行った。絹繊維は、500~2500kGyの照射で引張強度が低下し、とくに酸素存在下での劣化が著しかった。また、絹繊維は水に対して不溶であるが、放射線分解により著しく溶解性が増大した。照射した絹繊維を純水中で121
、1時間加熱した場合、酸素中2500kGyで約40%が溶解した。また、0.5N HCl溶液で100
、1hの加水分解を行った場合、未照射では約10%しか溶解しなかったが、酸素中2500kGyの照射では70%以上が溶解した。
Pewlong, W.*; Sudatis, B.*; 竹下 英文; 吉井 文男; 久米 民和
JAERI-Conf 2000-003, p.146 - 152, 2000/03
絹は重要な天然高分子資源の一つであり、タイにおける年間生産量1300トンは世界で五番目である。絹タンパク質は優れた生理学的な特性を有しており、新しい機能材料としての利用開発が期待されている。そこで、環境汚染防止及び資源のリサイクルに役立てることを目的に、絹タンパク質の放射線加工処理による改質効果に関する検討を行った。絹繊維は500~2500kGyの照射で引張強度が低下し、とくに酸素存在下での劣化が著しかった。また、絹繊維は水に対して不溶であるが、放射線分解により溶解性が著しく増大した。照射した絹繊維を純粋中で121
、1時間加熱した場合、酸素中2500kGyの照射で約40%が溶解した。0.5N HCl溶液で100
、1時間の加水分解を行った場合、未照射では約10%しか溶解しなかったが、酸素中2500kGyの照射では70%以上が溶解した。