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http://hdl.handle.net/2115/116
2024-03-29T11:00:25Z目次(英語)・奥付・裏表紙
http://hdl.handle.net/2115/91407
Title: 目次(英語)・奥付・裏表紙2024-03-24T15:00:00Z屈斜路カルデラ地域における相対重力測定
http://hdl.handle.net/2115/91406
Title: 屈斜路カルデラ地域における相対重力測定
Authors: 丸藤, 大樹; 名和, 一成; 高橋, 浩晃
Abstract: Relative gravity measurements with CG-5 gravimeter were performed in the Kussharo Caldera area in 2022 and 2023. The measurement time at a gravity point was set to 90 min to decrease the effects from gravimeter transportation. It was found that the perturbation after 60 min to be less than 5 μGal and good for measurement. Data with tidal, drift and scale factor corrections represented stable gravity values less than 10 μGal changes at TOPT, KUTC, TNBT. The gravity increases of 80 μGal at S049 was not explained by volcanic inflation modeling and might be due to artificial reasons.2024-03-24T15:00:00Z丸藤, 大樹名和, 一成高橋, 浩晃Relative gravity measurements with CG-5 gravimeter were performed in the Kussharo Caldera area in 2022 and 2023. The measurement time at a gravity point was set to 90 min to decrease the effects from gravimeter transportation. It was found that the perturbation after 60 min to be less than 5 μGal and good for measurement. Data with tidal, drift and scale factor corrections represented stable gravity values less than 10 μGal changes at TOPT, KUTC, TNBT. The gravity increases of 80 μGal at S049 was not explained by volcanic inflation modeling and might be due to artificial reasons.表紙・編集委員・目次(日本語)
http://hdl.handle.net/2115/91405
Title: 表紙・編集委員・目次(日本語)2024-03-24T15:00:00ZMinimal cylinders in the three-dimensional Heisenberg group
http://hdl.handle.net/2115/91380
Title: Minimal cylinders in the three-dimensional Heisenberg group
Authors: Kobayashi, Shimpei
Abstract: We study minimal cylinders in the three-dimensional Heisenberg group Nil3 using the generalized Weierstrass type representation, the so-called loop group method. We characterize all non-vertical minimal cylinders in terms of pairs of two closed plane curves which have the same signed area. Moreover, as a byproduct of the construction, spacelike CMC cylinders in the three-dimensional Minkowski space can also be obtained.2024-02-29T15:00:00ZKobayashi, ShimpeiWe study minimal cylinders in the three-dimensional Heisenberg group Nil3 using the generalized Weierstrass type representation, the so-called loop group method. We characterize all non-vertical minimal cylinders in terms of pairs of two closed plane curves which have the same signed area. Moreover, as a byproduct of the construction, spacelike CMC cylinders in the three-dimensional Minkowski space can also be obtained.Efficient Hydrogen Production by a Photoredox Cascade Catalyst Comprising Dual Photosensitizers and a Transparent Electron Mediator
http://hdl.handle.net/2115/91377
Title: Efficient Hydrogen Production by a Photoredox Cascade Catalyst Comprising Dual Photosensitizers and a Transparent Electron Mediator
Authors: Yoshimura, Nobutaka; Yoshida, Masaki; Kobayashi, Atsushi
Abstract: One-directional electron transport between a photocatalyst and redox mediator is crucial for achieving highly active Z-scheme water-splitting photocatalysis. Herein, a photoredox cascade catalyst that artificially mimics the electron transport chain in natural photosynthesis was synthesized from a Pt-TiO2 nanoparticle catalyst, two photosensitizers (RuCP6 and RuP6), and a visiblelight-transparent electron mediator (HCRu). During photocatalytic hydrogen evolution in the presence of a redox-reversible electron donor, [Co(bpy)3]2+ (bpy = 2,2 '-bipyridine), the HCRu-Zr-RuCP6-Zr-RuP6@Pt-TiO2 (PRCC-1) photocatalyst exhibited the highest reported initial (1 h) apparent quantum yield (iAQY = 2.23%) of dye-sensitized TiO2 photocatalysts to date. Furthermore, PRCC-1 successfully produced hydrogen when using hydroquinone monosulfonate (H2QS-) as the hydrogen source.2023-03-21T15:00:00ZYoshimura, NobutakaYoshida, MasakiKobayashi, AtsushiOne-directional electron transport between a photocatalyst and redox mediator is crucial for achieving highly active Z-scheme water-splitting photocatalysis. Herein, a photoredox cascade catalyst that artificially mimics the electron transport chain in natural photosynthesis was synthesized from a Pt-TiO2 nanoparticle catalyst, two photosensitizers (RuCP6 and RuP6), and a visiblelight-transparent electron mediator (HCRu). During photocatalytic hydrogen evolution in the presence of a redox-reversible electron donor, [Co(bpy)3]2+ (bpy = 2,2 '-bipyridine), the HCRu-Zr-RuCP6-Zr-RuP6@Pt-TiO2 (PRCC-1) photocatalyst exhibited the highest reported initial (1 h) apparent quantum yield (iAQY = 2.23%) of dye-sensitized TiO2 photocatalysts to date. Furthermore, PRCC-1 successfully produced hydrogen when using hydroquinone monosulfonate (H2QS-) as the hydrogen source.Cluster Toroidal Multipoles Formed by Electric-Quadrupole and Magnetic- Octupole Trimers : A Possible Scenario for Hidden Orders in Ca5Ir3O12
http://hdl.handle.net/2115/91375
Title: Cluster Toroidal Multipoles Formed by Electric-Quadrupole and Magnetic- Octupole Trimers : A Possible Scenario for Hidden Orders in Ca5Ir3O12
Authors: Hayami, Satoru; Tsutsui, Satoshi; Hanate, Hiroki; Nagasawa, Nobumoto; Yoda, Yoshitaka; Matsuhira, Kazuyuki
Abstract: Cluster multipole orderings composed of atomic high-rank multipole moments are theoretically investigated with a 5d-electron compound Ca5Ir3O12 in mind. Ca5Ir3O12 exhibits two hidden orders: One is an intermediate-temperature phase with time-reversal symmetry and the other is a low-temperature phase without time-reversal symmetry. By performing the symmetry and augmented multipole analyses for a d-orbital model under the hexagonal point group D3h, we find that the 120 degrees-type ordering of the electric quadrupole corresponds to cluster electric toroidal dipole ordering with the electric ferroaxial moment, which can become the microscopic origin of the intermediate-temperature phase in Ca5Ir3O12. Furthermore, based on 193Ir synchrotron-radiation-based Mossbauer spectroscopy, we propose that the low -temperature phase in Ca5Ir3O12 is regarded as a coexisting state with cluster electric toroidal dipole and cluster magnetic toroidal quadrupole, the latter of which is formed by the 120 degrees-type ordering of the magnetic octupole and accompanies a small uniform magnetization as a secondary effect. Our results provide a clue to two hidden phases in Ca5Ir3O12.2023-03-14T15:00:00ZHayami, SatoruTsutsui, SatoshiHanate, HirokiNagasawa, NobumotoYoda, YoshitakaMatsuhira, KazuyukiCluster multipole orderings composed of atomic high-rank multipole moments are theoretically investigated with a 5d-electron compound Ca5Ir3O12 in mind. Ca5Ir3O12 exhibits two hidden orders: One is an intermediate-temperature phase with time-reversal symmetry and the other is a low-temperature phase without time-reversal symmetry. By performing the symmetry and augmented multipole analyses for a d-orbital model under the hexagonal point group D3h, we find that the 120 degrees-type ordering of the electric quadrupole corresponds to cluster electric toroidal dipole ordering with the electric ferroaxial moment, which can become the microscopic origin of the intermediate-temperature phase in Ca5Ir3O12. Furthermore, based on 193Ir synchrotron-radiation-based Mossbauer spectroscopy, we propose that the low -temperature phase in Ca5Ir3O12 is regarded as a coexisting state with cluster electric toroidal dipole and cluster magnetic toroidal quadrupole, the latter of which is formed by the 120 degrees-type ordering of the magnetic octupole and accompanies a small uniform magnetization as a secondary effect. Our results provide a clue to two hidden phases in Ca5Ir3O12.流れ藻から得られたアサガオクラゲ(十文字クラゲ綱)の報告
http://hdl.handle.net/2115/91370
Title: 流れ藻から得られたアサガオクラゲ(十文字クラゲ綱)の報告
Authors: 筒井, 幸多; 角井, 敬知
Abstract: Staurozoans, or stalked jellyfishes, are sessile cnidarians and lack planktonic stages in their life cycle. Among staurozoans attaching to seaweeds, there are species showing wide distributional range, suggesting their long passive dispersal by using drifting seaweeds; however, the report of staurozoans on drifting seaweeds is so limited. In this study, I report live Haliclystus tenuis KISHINOUYE, 1910 individuals from stranded and drifting Sargassum seaweeds collected in Otaru, Hokkaido, Japan. More than 50 individuals at various developmental stages were found on large lumps of stranded seaweeds in July. One individual was found on a small drifting seaweed in August. This finding suggests that drifting seaweeds may help long-distance dispersal by epiphytic staurozoans.
Description: 同論文は,角井先生が執筆補助を行っていることから、HUSCAPには共著として登録する2024-03-19T15:00:00Z筒井, 幸多角井, 敬知Staurozoans, or stalked jellyfishes, are sessile cnidarians and lack planktonic stages in their life cycle. Among staurozoans attaching to seaweeds, there are species showing wide distributional range, suggesting their long passive dispersal by using drifting seaweeds; however, the report of staurozoans on drifting seaweeds is so limited. In this study, I report live Haliclystus tenuis KISHINOUYE, 1910 individuals from stranded and drifting Sargassum seaweeds collected in Otaru, Hokkaido, Japan. More than 50 individuals at various developmental stages were found on large lumps of stranded seaweeds in July. One individual was found on a small drifting seaweed in August. This finding suggests that drifting seaweeds may help long-distance dispersal by epiphytic staurozoans.Production cross sections of 47Sc via alpha-particle-induced reactions on natural calcium up to 29 MeV
http://hdl.handle.net/2115/91288
Title: Production cross sections of 47Sc via alpha-particle-induced reactions on natural calcium up to 29 MeV
Authors: Aikawa, Masayuki; Hanada, Yukina; Ichinkhorloo, Dagvadorj; Haba, Hiromitsu; Takács, Sándor; Ditrói, Ferenc; Szűcs, Zoltán
Abstract: Production cross sections of a medical radioisotope 47Sc via alpha-particle-induced reactions on natural calcium were measured up to 29 MeV. The stacked-foil activation technique and gamma-ray spectrometry were adopted for the experiment. Cross sections of simultaneously formed radionuclides 46,44m,44g,43Sc and 47Ca were also determined. Physical yields of the alpha-particle-induced reactions on natCa and 44Ca were deduced from the measured cross sections.2022-03-14T15:00:00ZAikawa, MasayukiHanada, YukinaIchinkhorloo, DagvadorjHaba, HiromitsuTakács, SándorDitrói, FerencSzűcs, ZoltánProduction cross sections of a medical radioisotope 47Sc via alpha-particle-induced reactions on natural calcium were measured up to 29 MeV. The stacked-foil activation technique and gamma-ray spectrometry were adopted for the experiment. Cross sections of simultaneously formed radionuclides 46,44m,44g,43Sc and 47Ca were also determined. Physical yields of the alpha-particle-induced reactions on natCa and 44Ca were deduced from the measured cross sections.A few topics on total variation flows
http://hdl.handle.net/2115/91283
Title: A few topics on total variation flows
Authors: Giga, Yoshikazu; Kuroda, Hirotoshi; Lasica, Michal
Abstract: Total variation gradient flows are important in several applied fields, including image analysis and materials science. In this paper, we review a few basic topics including definition of a solution, explicit examples and the notion of calibrability, finite time extinction, and some regularity properties of solutions. We focus on the second-order flow (possibly with weights) and the fourth-order flow. We also discuss the fractional cases.2024-03-13T15:00:00ZGiga, YoshikazuKuroda, HirotoshiLasica, MichalTotal variation gradient flows are important in several applied fields, including image analysis and materials science. In this paper, we review a few basic topics including definition of a solution, explicit examples and the notion of calibrability, finite time extinction, and some regularity properties of solutions. We focus on the second-order flow (possibly with weights) and the fourth-order flow. We also discuss the fractional cases.Embedding Alexander quandles into groups
http://hdl.handle.net/2115/91254
Title: Embedding Alexander quandles into groups
Authors: Akita, Toshiyuki
Abstract: For any twisted conjugation quandle Q, and in particular any Alexander quandle, there exists a group G such that Q is embedded into the conjugation quandle of G2023-03-03T15:00:00ZAkita, ToshiyukiFor any twisted conjugation quandle Q, and in particular any Alexander quandle, there exists a group G such that Q is embedded into the conjugation quandle of G