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Encapsulated Platinum–Tin Nanoparticles in Silicalite-1 Zeolite for Methylcyclohexane Dehydrogenation
No full textCatalytic dehydrogenation of methylcyclohexane (MCH) is of great importance for hydrogen storage and transportation, but currently used Pt-based nanoparticle catalysts still suffer from insufficient activity, low selectivity, and short-term stability. In this study, we encapsulated Pt–Sn nanoparticles into the silicalite-1 (S-1) matrix and incorporated Sn into the zeolite framework through one-pot hydrothermal synthesis to overcome the above problems. These Pt–Sn bimetallic catalysts were designed for the first time with a high Sn content (2.8–3.9 wt %, Sn/Pt ratio = 6–8) in zeolite mother gel for MCH dehydrogenation. The introduction of Sn significantly improved the activity and durability of Pt@S-1. Especially, the PtSn@S-1 (Sn/Pt ratio = 6) catalyst showed high MCH conversion (>80% for 2 h) and toluene (TOL) selectivity (∼100%) without cofeeding H2. Even after a long-term stability test for 33 h under a weight hourly space velocity (WHSV) of 120,000 mL/g/h, no obvious deactivation was observed, and this catalyst retained a superior H2 evolution rate normalized with a surface Pt content of 1343 mmolH2/gPt/min. The structure–catalytic property relationship of PtSn@S-1 catalysts was systematically studied. Upon Sn introduction, PtOx species on Pt@S-1 were transformed into the PtSn alloy. With the further increase of the Sn/Pt ratio from 1 to 6, Sn was gradually incorporated into the zeolite framework, and this PtSn alloy evolved into a core–shell structure with a Pt core and a Sn shell. Despite the reduced proportion of surface Pt, these unique structures enabled the modification of the Pt local structure, promoted TOL desorption, and enhanced the stability of Pt–Sn nanoparticles, therefore achieving high activity, selectivity, and durability for MCH dehydrogenation.journal articl
ヴィジュアル系バンドの衰退原因調査 : インタビューを通した質的側面による分析
Get PDF教育研究推進室の活動報告. 大学院生支援事業. 調査奨励金報告書（2024年度）departmental bulletin pape
全國金満家大番附(講談倶楽部19巻1號附録)
Get PDF全國金満家大番附（講談倶楽部19巻1號附録）画像（PDF）および、テキストデータ（CSV）。CSVファイルは、原画像をダブルチェック体制でテキスト化したものである。旧字体や異体字は、可能な限り原典の表記のまま入力した。原典で読み取れなかった文字や、判読が困難だった箇所は、■（黒塗り四角）で入力した。datase
Systematic review and methodological comparison of TOD typologies based on the node-place model
No full textThis study conducts a systematic review of 65 papers on Transit-Oriented Development (TOD) typology based on the node-place model and performs a subsequent site study on the Chukyo Metropolitan Area (CMA) and Nagoya to examine two modeling approaches—the heuristic models based on the previous framework and the exploratory factor models—applied at two different spatial scales, resulting in four comparative cases. Our review classified research trends into five method types: NPM (Node-Place Model), extended NPM, mixed NPM, validated NPM, and visually supported NPM. Major methodological gaps shared across these types include (1) indicator assignment to dimensions such as node, place, and walkability, and (2) the variation arising from spatial scopes. Subsequent empirical comparisons provide the following results and implications for future studies: First, exploratory-derived factors were more detailed than the heuristic dimensions, indicating the potential for nuanced classification, while the overall patterns partially validated the existing frameworks. This finding suggests that the distinguishing between transit accessibility measures and transit network performance, including modal differences, can function as an alternative station assessment. Second, spatial scope must be carefully considered in TOD typologies, which is supported by the detailed results at the city scale, in contrast to the cohesive representation at the metropolitan scale. Third, the internal correlations among indicators defined under walkability or functionality support the validity of the literature, yet underscore the need for exploring indicator-level relationships. Finally, we suggest an integration of the heuristic and data-driven approaches to enable multidimensional interpretation and support sequential decision-making.journal articl
Spatiotemporal dynamics of turbulent fluctuations in the presence of toroidal zonal flow in reversed field pinch plasma
No full textIn this study, we investigate the spatiotemporal dynamics of fluctuations in the presence of a toroidally directed zonal flow using two pairs of radial capacitive arrays with finer spatial resolution than the observed toroidal zonal flow. Conditional sampling is employed to evaluate frequency- and time-resolved behavior with respect to the toroidal zonal flow phase. We identify three distinct types of fluctuations, each exhibiting different spatiotemporal dynamics synchronized with the toroidal zonal flow. These modes are modulated in space and time in accordance with the phase of the toroidal zonal flow. The mechanism underlying the formation of spatiotemporal structures is discussed in terms of long-range correlations and wave-kinetic characteristics.journal articl
Regiodivergent Photocatalytic Annulation for the Synthesis of gem-Difluorinated Cyclic Hydrocarbons
No full textRegiodivergent synthesis is a powerful strategy for expanding chemical space. Given the significance of fluorine-containing molecules in pharmaceutical sciences, a regiodivergent [3+2] cycloaddition of gem-difluorocyclopropyl urea to olefins and [1.1.0]-bicyclobutanes was developed by employing cationic iridium complexes as photocatalysts under visible-light irradiation. By properly selecting a counteranion of the photocatalyst and tuning the reaction conditions, each regioisomeric cyclic hydrocarbon with a defined gem-difluoromethylene disposition was directly assembled with high selectivity. Mechanistic elucidation revealed the critical relevance of the basicity of the photocatalyst counteranion to the regiochemical outcome. The reaction diverges depending on the intervention of deprotonation of the initially generated urea radical cation by the pairing anion to form the corresponding neutral radical; this not only governs the regioselective ring opening of the cyclopropane moiety but also modulates the relative reactivity of the two resulting terminal carbon radicals, thereby dictating the dominant pathway.journal articl
Simple and early prediction of severe CAR-T-related adverse events after Axi-cel infusion by initial high fever
No full textChimeric antigen receptor T-cell (CAR-T)-related adverse events (CAR-AEs), such as immune effector cell-associated neurotoxicity syndrome (ICANS) and cytokine release syndrome (CRS), can be life-threatening and may require high-dose steroids. Identifying patients at high risk for severe CAR-AEs in a simplified way is crucial for early therapeutic intervention. This retrospective study analyzed 44 patients treated with axicabtagene ciloleucel (Axi-cel) to identify predictive factors for severe CAR-AEs. We found that grade ≥ 3 ICANS, hemophagocytic syndrome, and ICU admission were associated with a greater need for high-dose steroids, which we defined as events associated with high-dose steroids (EHS). The incidence of EHS was significantly higher in patients who developed an initial fever (≥ 38.6 °C) within 24 h of CAR-T infusion (p < 0.001). Progression-free survival (PFS) was significantly shorter in patients with EHS compared to those without EHS (p < 0.001). Additionally, patients who developed a fever within 24 h and those with a peak fever of ≥ 38.6 °C both tended to have higher peak CAR-T counts compared to other patients. Our findings suggest that an initial fever (≥ 38.6 °C) within 24 h of Axi-cel infusion may predict severe CAR-AEs requiring high-dose steroids, and that EHS is associated with worse PFS.journal articl
Late fluid flow in a primitive asteroid revealed by Lu–Hf isotopes in Ryugu
No full textCarbonaceous asteroids are the source of the most primitive meteorites and represent leftover planetesimals that formed from ice and dust in the outer Solar System and may have delivered volatiles to the terrestrial planets. Understanding the aqueous activity of asteroids is key to deciphering their thermal, chemical and orbital evolution, with implications for the origin of water on the terrestrial planets. Analyses of the objects, in particular pristine samples returned from asteroid Ryugu, have provided detailed information on fluid–rock interactions within a few million years after parent-body formation. However, the long-term fate of asteroidal water remains poorly understood. Here we present evidence for fluid flow in a carbonaceous asteroid more than 1 billion years after formation, based on the 176Lu^–176Hf decay systematics of Ryugu samples, which reflect late lutetium mobilization. Such late fluid flow was probably triggered by an impact that generated heat for ice melting and opened rock fractures for fluid migration. This contrasts the early aqueous activity powered by short-lived radioactive decay, with limited fluid flow and little elemental fractionation. Our results imply that carbonaceous planetesimals accreted by the terrestrial planets could have retained not only hydrous minerals but also aqueous water, leading to an upwards revision of the inventory of their water delivery by a factor of two to three.journal articl
