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Effect of Large-scale Turbulent Structures on Drag Reduction Mechanisms in Viscoelastic Flow
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On the analysis of quantum algorithms for solving the short principal ideal problem
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Introduction of oxygen‐containing functional groups to carbon fiber surfaces to enhance the bending strength of PA6‐based carbon‐fiber‐reinforced thermoplastics
No full textCarbon-fiber-reinforced thermoplastics (CFRTPs) are recyclable composite materials with excellent mechanical properties. However, for CFRTPs to be used in automobile applications, enhanced mechanical properties are required. To meet this challenge, the surface adhesion between the carbon fibers and thermoplastics must be improved. In this study, we developed surface treatment techniques for carbon fibers using the radical initiator dimethyl 2,2′-azobis(2-methylpropionate) (V-601) to introduce oxygen-containing functional groups to the carbon fibers through radical chemical reactions. Using x-ray photoelectron spectroscopy, we showed that the surface adhesion between the carbon fibers and a nylon thermoplastic resin (PA6) improved owing to hydrogen bonding with carbonyl groups on the carbon fiber surface, which enhanced the mechanical properties of the CFRTP. Moreover, we demonstrated control of the mechanical properties of the CFRTP by varying the V-601-acetone concentration. The findings of this study can be used to develop automobile applications for PA6-based CFRTPs.First published: 12 April 2025journal articl
秋田県湯沢市、コケ沼湿原のコア層序と年代
Get PDFKoke-numa Marsh, located on the Kijiyama Plateau in Yuzawa City, Akita Prefecture, is a high moor surrounded by plateaus. The marsh measures 320 m north to south and 390 m east to west, with a maximum depth of 5 m. The surface layer is composed of floating islands of moss approximately 1 to 3 m thick. There are several marshes similar to Koke-numa in the surrounding area. In this study, core samples up to 6.5 min depth were collected from this marshland. The lower to middle part of the core sample was a peat layer dominated by wood chips, while the upper part of the core sample was dominated by a peat layer of Sphagnum moss. Volcanic ash correlative with Towada-a (To-a) ash (AD 915) was identified at a depth of 3.7 m. It dates back to approximately 6 cal ka BP, but it is possible that the Koke-numa Marsh expanded after approximately 2 cal ka BP.秋田県湯沢市、木地山高原に位置するコケ沼湿原は、その周囲を高原台地で囲まれる高層湿原である。湿原の大きさは南北320m、東西390m、最大水深5mで、表層にミズゴケ類が厚さ約1～3mの浮島を構成している。また、コケ沼湿原の周囲にも同様の湿原が多数存在する。この研究では、コケ沼湿原から最大6.5mのコア試料を採取した。コア試料の下部から中部にかけては木片が卓越する泥炭層であり、上部はミズゴケ泥炭層が卓越する。深さ3.7mに十和田a火山灰(AD915)に対比される火山灰が確認された。14c年代では約6calkaBPまで遡ることができるが、約2calkaBP以降にコケ沼が拡大した可能性がある。departmental bulletin pape
福島県大熊町の農地における土壌の137Cs濃度
Get PDFRadiocaesium (137Cs) released by the Fukushima Dai-ichi Nuclear Power Plant accident in 2011 still remains in agricultural lands in the Hamadori region of Fukushima Prefecture. In order to obtain clues to evaluate the distribution of Cs in soil in agricultural lands in the Hamadori area, 137Cs concentration and CHNS contents in bulk fractions, and trace metal element concentrations pf exchangeable fractions were measured on samples collected in Kitamukai, Okuma-machi, Fukushima Prefecture. 137Cs concentration was about 39 to 42 Bq/g in the surface layer and less than 1 Bq/g at 12.5 to 30 cm. CHNS concentrations were 5%, 1%, 0.4%, and 0.05% in the surface layer, and 1%, 0.7%, 0.08%, and 0.002% in the 15-30 cm layer, respectively. Exchangeable Cs, on the other hand, was 0.107 mg/kg at 0-2.5 cm and gradually increased in concentration with depth to 0.124 mg/kg at 27.5-30 cm.福島県浜通り地域の農地には2011年の福島第一原発の事故で放出された放射性Cs(137Cs)が現在も残留している。浜通り地域の農地における土壌中のCs深度分布を評価する手がかりを得ることを目的として、福島県大熊町北向で採取された試料についてバルク成分の137Cs濃度、CHNS分析、交換態成分の微量金属元素分析を行った。137Cs濃度は表層で約39-42Bq/gであり、12.5-30cmでは1Bq/g未満となった。CHNS濃度は表層ではそれぞれ5%,1%,0.4%,0.05％で、15—30cmでは表層より低い1%,0.7%,0.08%,0.002％だった。一方で、交換態Csは0-2.5cmでは0.107mg/kgで、深くなるにつれ徐々に濃度が高くなり、27.5-30cmでは0.124mg/kgであった。departmental bulletin pape
未公開のメタデータを流用したい ～NBDCヒトDBから包括的未病DBへ～
Get PDFジャパン・オープンサイエンス・サミット2025（Japan Open Science Summit 2025、JOSS2025）(2025年6月23日～2025年6月27日、国立情報学研究所/ハイブリッド）、「F1 研究データをより見つけやすくするためのメタデータ変換と学術機関リポジトリへの登録」セッション発表資料conference outpu
