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100 MeV/nucleonPohl, T.*; Sun, Y. L.*; Obertelli, A.*; Lee, J.*; G
mez-Ramos, M.*; 緒方 一介*; 吉田 数貴; Cai, B. S.*; Yuan, C. X.*; Brown, B. A.*; et al.
Physical Review Letters, 130(17), p.172501_1 - 172501_8, 2023/04
被引用回数：5 パーセンタイル：92.42(Physics, Multidisciplinary)大きなフェルミ面非対称性を持つ陽子過剰な
O原子核からの100MeV/nucleonでの陽子による陽子・中性子除去反応について報告した。この結果は、quasi-freeノックアウト反応、非弾性散乱、核子移行反応を含む複数の反応機構の定量的寄与を初めて示すものである。このようなエネルギー領域では通常無視される非弾性散乱と核子移行の寄与が、弱束縛陽子と強束縛中性子の除去反応断面積にそれぞれ約50%と30%寄与していることが示された。
斉藤 淳一; 小林 洋平*; 澁谷 秀雄*
Materials Transactions, 62(10), p.1524 - 1532, 2021/10
被引用回数：5 パーセンタイル：41.35(Materials Science, Multidisciplinary)高速炉の冷却材である液体ナトリウムの新規技術の創出の一環として、液体ナトリウムの濡れ性制御の研究開発を実施しており、本発表はその基礎的研究として、純金属の液体ナトリウムと液体錫の濡れ性を接触角により評価した。また、界面の原子間相互作用を界面クラスターモデルを用いて分子軌道法により理論計算した。その結果、界面の原子間結合力と濡れ性には相関があることが明らかになった。この知見は今後、ナトリウム濡れ性を制御するうえで、重要な情報となる。
斉藤 淳一; 小林 洋平*; 澁谷 秀雄*
日本金属学会誌, 85(3), p.110 - 119, 2021/03
被引用回数：1 パーセンタイル：8.06(Metallurgy & Metallurgical Engineering)Wettability of pure transition metals with liquid sodium or liquid tin has been evaluated using a contact angle droplet method. Titanium, iron, nickel, copper and molybdenum pure metals were selected as specimens in this experiment. All experiments were carried out in high purity argon gas and extremely low moisture to avoid influence of oxygen to liquid metal. Measurement temperature was set just above the melting temperature of each liquid metal. As a result, for both liquid sodium and liquid tin, the measured contact angle changed depending on the atomic number of substrate metals. An electronic structure of the interface between liquid metal and substrate metal was calculated by the molecular orbital method. Simple cluster models of the interface between liquid metal and substrate transition metals were used in this calculation. It was found that the calculation results well express an electronic state of interface. The atomic bonding between liquid metal atom and substrate metal atom changed depending on the kind of substrate metal. Also, the atomic bonding between substrate metal atoms changed similarly. It became clear that there was a reasonable relationship between an atomic bonding ratio and the contact angle. It clearly suggested the atomic bonding affected wettability between liquid metal and substrate metal. The atomic bonding was obtained as one of indications to reveal the wettability by transition metals with liquid metals.
clusters in dilute neutron-rich matter田中 純貴*; Yang, Z.*; Typel, S.*; 足立 智*; Bai, S.*; van Beek, P.*; Beaumel, D.*; 藤川 祐輝*; Han, J.*; Heil, S.*; et al.
Science, 371(6526), p.260 - 264, 2021/01
被引用回数：48 パーセンタイル：99.12(Multidisciplinary Sciences)ノックアウト反応を用いることで、中性子過剰な錫同位体の核表面でのクラスター形成を実験的に確かめた。実験で得られた、質量数とともに単調に減少するノックアウト断面積は理論による予言と非常に良く一致し、クラスター形成率と中性子スキン厚との関係を示唆している。
spp. under the ISS environmental conditions for performing exposure experiments of microbes in the Tanpopo mission河口 優子*; Yang, Y.*; 川尻 成俊*; 白石 啓祐*; 高須 昌子*; 鳴海 一成*; 佐藤 勝也; 橋本 博文*; 中川 和道*; 谷川 能章*; et al.
Origins of Life and Evolution of Biospheres, 43(4-5), p.411 - 428, 2013/10
被引用回数：41 パーセンタイル：80.34(Biology)In the Tanpopo mission, we have proposed to carry out experiments on capture and space exposure of microbes at the Exposure Facility of the Japanese Experimental Module of the International Space Station (ISS). Microbial candidates for the exposure experiments in space include spp. We have examined the survivability of spp. under the environmental conditions in ISS in orbit. A One-year dose of heavy-ion beam irradiation did not affect the viability of spp. within the detection limit. Exposure of various thicknesses of deinococcal cell aggregates to UV radiation revealed that a few hundred micrometer thick aggregate of deinococcal cells would be able to withstand the solar UV radiation on ISS for 1 year. We concluded that aggregated deinococcal cells will survive the yearlong exposure experiments. We propose that microbial cells can aggregate as an ark for the interplanetary transfer of microbes, and we named it "massapanspermia".
坂中 章悟*; 吾郷 智紀*; 榎本 収志*; 福田 茂樹*; 古川 和朗*; 古屋 貴章*; 芳賀 開一*; 原田 健太郎*; 平松 成範*; 本田 融*; et al.
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.205 - 207, 2008/06
コヒーレントX線,フェムト秒X線の発生が可能な次世代放射光源としてエネルギー回収型リニアック(ERL)が提案されており、その実現に向けた要素技術の研究開発が日本国内の複数研究機関の協力のもと進められている。本稿では、ERL放射光源の研究開発の現状を報告する。
横堀 伸一*; 小林 憲正*; 三田 肇*; 薮田 ひかる*; 中川 和道*; 鳴海 一成; 林 宣宏*; 富田 香織*; 河口 優子*; 清水 康之*; et al.
no journal, ,
現在準備を進めている国際宇宙ステーション(ISS)日本実験棟(JEM)の曝露部での宇宙実験「有機物・微生物の宇宙曝露と宇宙塵・微生物の捕集(たんぽぽ)」の中の、微生物と有機物の宇宙曝露実験についてその進行状況を報告する。微生物宇宙曝露実験は、生物の長期宇宙生存可能性の検討、有機物宇宙曝露実験は、宇宙起源の生命の起原に関連する有機物の宇宙での変成を検討する。微生物、有機物の双方について、宇宙曝露サンプルをほぼ選定を終え、宇宙曝露実験に対する地上対照データの収集を引き続き進めている。また、これらのサンプルの宇宙曝露方法についても、検討を行っている。
spp. under the ISS environmental conditions for performing exposure experiments of microbes in the Tanpopo mission河口 優子*; Yang, Y.*; 川尻 成俊*; 白石 啓祐*; 鳴海 一成*; 佐藤 勝也; 橋本 博文*; 中川 和道*; 谷川 能章*; 桃木 洋平*; et al.
no journal, ,
To investigate the interplanetary transfer of life, numerous exposure experiments have been carried out on various microbes in space since the 1960s. In the Tanpopo mission, we have proposed to carry out experiments on capture and space exposure of microbes at the Exposure Facility of the Japanese Experimental Module of the International Space Station (ISS). Microbial candidates for the exposure experiments in space include spp.: 
, 
, and 
. We have examined the survivability of spp. under the environmental conditions in ISS orbit (i.e., long exposure to heavy-ion beams, temperature cycles, vacuum and UV irradiation). We concluded that aggregated deinococcal cells will survive the yearlong exposure experiments. We propose that the microbial cells aggregate as an ark for the interplanetary transfer of microbes, and named it "Massapanspermia".
属の生存能力の検証(たんぽぽ計画)河口 優子*; Yang, Y.*; 村野 由佳*; 原田 美優*; 川尻 成俊*; 白石 啓祐*; 高須 昌子*; 鳴海 一成*; 佐藤 勝也; 橋本 博文*; et al.
no journal, ,
微生物が凝集体状で長期にわたり宇宙空間で生存が可能であることを検証することを目的とした。放射線耐性菌である属の凝集体を作製し、紫外線耐性を調べた。乾燥した菌体を異なる厚み(1-2000
m)に調整し、凝集体とした。宇宙空間で照射される波長領域であるVacuum UV(172nm)、UV-C (254nm)、UV-B(280-315nm)を真空下で凝集体に照射した。その後各凝集体の生存率を計測した。その結果、全ての紫外線照射下での属の生存率は、凝集体の厚みに依存した。さらに実験値をもとに照射強度と厚みと生存率の関係をモデル化した。全ての波長領域において1m(単層)では生存率が急速に低下した。しかし数mmあれば照射強度が増加しても高い生存率を示した。これは微生物の凝集体の側面の細胞は死滅するが紫外線を遮蔽し、内部の細胞は生存が可能であることが示している。このことから、微生物が凝集体を担体として宇宙空間を移動可能であるとするmasa-pansperumiaを提唱する。
斉藤 淳一; 小林 洋平*; 澁谷 秀雄*
no journal, ,
Wettability of pure metal by liquid sodium has been studied in order to control the wettability. In order to understand theoretically the wettability the electronic state of interface between liquid metal and substrate metal calculated and an atomic bonding at interface obtained. Consequently, it became clear that the contact angle which is one of indications of wettability was related with the atomic bonding at interface. An electronic state of interface between liquid low-melting temperature alloy and pure metal was calculated to evaluate the experimental results of wettability of pure metal using the low-melting temperature alloy. And the contact angle was evaluated by the atomic bonding of interface. The molecular orbital calculation was utilized for the calculation of electronic state of interface. The low-melting temperature alloy consists of bismuth, tin and indium. Aluminum, titanium, iron, nickel, copper, zirconium, niobium and molybdenum were selected as the substrate metal. From the calculation result an electronic density of state of interface was similar to that of bulk metal. It means the electronic state of interface was expressed well in this calculation. It became clear that an atomic bonding at interface changed with the atomic number of substrate metal. We will report a relationship between the atomic bonding and the contact angle of wettability in the presentation.
小林 洋平*; 斉藤 淳一; 澁谷 秀雄*
no journal, ,
Wettability is one of properties between liquid and solid material and it is very important factor affecting on acoustic property, corrosion property and so on. In this study, some experiments of wettability of pure metals were performed using the low-melting temperature alloy in order to get many fundamental information of wettability. The low-melting temperature alloy consists of bismuth, tin and indium. Aluminum, titanium, iron, nickel, copper, zirconium, niobium and molybdenum were used as a substrate metal. Test temperature was 353K and test atmosphere was in air. A droplet of the low-melting temperature alloy was put on the substrate metal and a contact angle was measured. From the measurement results, the contact angle changed depending on the substrate metal. It is suggested that the contact angle has relations with the atomic bonding between the s
斉藤 淳一; 小林 洋平*; 澁谷 秀雄*
no journal, ,
Wettability of metal by liquid sodium has been studied to understand and control the wettability. As part of this study, the wettability of metal by water was investigated by experiment and electron theory. The electronic states of interface between water and pure metal was calculated using the cluster models of pure metal and water. The DV-X alpha method was utilized for this calculation. Nine kinds of pure metal were selected as the substrate metal. An electronic density of state of interface was similar to that of bulk metal. In all the substrate metal the strength of atomic bonding between water and substrate metal atom was weaker than that between substrate metal atoms. Furthermore it was weaker than that between sodium and substrate metal atom calculated in our previous study. It is considered that this calculation result is related the different of contact angle with metal between water and liquid sodium.
斉藤 淳一; 小林 洋平*
no journal, ,
The purpose of this study deeply understands of wettability from the relationship between the contact angle and the atomic bond of the interface by using the result of theoretical calculation. As the substrate metal, nine kinds of pure metals and alloys were used. All of the contact angle were smaller than 90 degrees. It means the wettability of water with metal is good. The contact angle results have been evaluated using the bond order, which shows the strength of atomic interaction at the interface. For liquid metals and metals, the contact angle could be explained by the atomic bond at the interface. It was found that there is a good correlation between the contact angle and the atomic bond without contradictory to Young's equation even if the atomic bond at the interface is used. This suggests that it is possible to predict the wettability of an unknown metal with water.
澁谷 秀雄*; 田口 朋弥*; 斉藤 淳一; 池田 明日香*; 小林 洋平*
no journal, ,
冷却材にナトリウムを使用する高速炉は有力候補の一つである。高速炉において、ナトリウム機器やその部位により要求される濡れ性が異なっており、これを制御することは高速炉の安全性や性能向上に貢献できると考えられる。本研究では、ナトリウムの濡れ性制御に向けた基礎的に知見を得ることを目的として、ナトリウムと融点が近く、取扱いの容易なIn-Bi-Sn系低融点合金を用いて、切削により表面に種々の凸部高さと凸部間隔を付与した黄銅基板を用いて、水中における液体金属の濡れ性に及ぼす基板表面性状の影響を調査した。
