界面活性剤とSi基板からの溶解ケイ酸種を用いた2次元シリカナノ構造体の作製

早大学位記番号:新7831早稲田大

Release of Inorganic Phosphate from Ferric Phytate by Bacteria Isolated from Arbuscular Mycorrhizal Fungal Hyphosphere

Poster Session

経皮的心肺補助装置小型化のための新しい血液ポンプの開発

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 牛田 多加志, 東京大学教授 小野 稔, 東京大学講師 山本 希美子, 東京大学講師 細谷 紀子, 東京大学教授 小山 博史University of Tokyo(東京大学

Phosphorous Uptake from Organic Matter via AM fungi : Possible Involvement of Phytate-Degrading Bacteria

Poster Sessio

Data-driven Exploration of New Pressure-induced Superconductivity in PbBi2_2Te4_4 with Two Transition Temperatures

Candidates compounds for new thermoelectric and superconducting materials, which have narrow band gap and flat bands near band edges, were exhaustively searched by the high-throughput first-principles calculation from an inorganic materials database named AtomWork. We focused on PbBi$_2$Te$_4$ which has the similar electronic band structure and the same crystal structure with those of a pressure-induced superconductor SnBi2Se4 explored by the same data-driven approach. The PbBi$_2$Te$_4$ was successfully synthesized as single crystals using a melt and slow cooling method. The core level X-ray photoelectron spectroscopy analysis revealed Pb2+, Bi3+ and Te2- valence states in PbBi$_2$Te$_4$. The thermoelectric properties of the PbBi$_2$Te$_4$ sample were measured at ambient pressure and the electrical resistivity was also evaluated under high pressure using a diamond anvil cell with boron-doped diamond electrodes. The resistivity decreased with increase of the pressure, and two pressure-induced superconducting transitions were discovered at 3.4 K under 13.3 GPa and at 8.4 K under 21.7 GPa. The data-driven approach shows promising power to accelerate the discovery of new thermoelectric and superconducting materials