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Ikaros3D: a real-time 3D fine spatial mesh kinetics simulator using POD
No full textToward the development of digital triplets for more effective reactor physics education, the present study develops a real-time 3D fine spatial mesh kinetics simulator based on the proper orthogonal decomposition (POD). The present simulator, Ikaros3D, is specifically designed for a simplified coupled core model using the pre-tabulated compressed coefficient matrices for the POD-based kinetics calculation. It enables us to accurately calculate the time variation of flux distribution in real-time as well as actual experiments and promotes students’ better understanding of the spatial dependence of dynamic reactivity considering the positions of the neutron detectors.Published online: 15 Aug 2025journal articl
Inclusive Education for Myanmarese Migrant Students in Mae Sot, Thailand
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Enhanced magnetic hyperthermia of green-synthesized CoFe2O4/C-dots nanocomposites utilizing moringa oleifera extract and watermelon peels
No full textThis research focuses on cobalt ferrite (CoFe2O4)/carbon dots (C-dots) nanocomposites synthesized through green synthesis, utilizing Moringa oleifera leaf extract and watermelon rind waste for magnetic hyperthermia applications in cancer therapy, enabling targeted and localized heating. CoFe2O4 nanoparticles were synthesized via a co-precipitation method, while the C-dots were produced hydrothermal. Sonication was applied to connect the C-dots to the surface of CoFe2O4. The X-ray diffraction spectrum of CoFe2O4/C-dots shows a cubic spinel structure with crystallite sizes ranging from 7.6 nm to 6.2 nm, where the crystallite size decreases with increasing C-dots concentration. Transmission electron microscopy observations reveal that the size of the nanocomposites is almost consistent at around 11.8–12.1 nm. The Co–O and Fe–O functional groups detected in the nanocomposite indicate that CoFe2O4 remains after fabrication. The identified C–O, Cdouble bondC, and O–H groups also confirm the presence of C-dots on the CoFe2O4 surface. The UV–Vis absorption spectrum peaks at 282 nm for C-dots and 218 nm for CoFe2O4. The addition of C-dots affects the saturation magnetization and domain size, which are 55–56.4 emu/g and 3.2–3.5 nm, indicating good magnetic properties. Additionally, the specific absorption rate (SAR) value of CoFe2O4/C-dots depends on magnetization, with the SAR value decreasing with increasing C-dots concentration while increasing with higher frequency and alternating magnetic field. The highest SAR values for CoFe2O4 and CoFe2O4/C-dots are 626 mW/g and 485 mW/g, respectively, which decrease with an increase in C-dots concentration. These results indicate that CoFe2O4/C-dots synthesized using green methods are promising candidates that can optimize performance in magnetic hyperthermia applications in the future.journal articl
Aldol Condensation of Bis(pentafluorophenyl)boron Enolates for the Synthesis of α-Pentafluorophenyl-Substituted α,β-Unsaturated Carbonyl Compounds
No full textα-Pentafluorophenyl-substituted α,β-unsaturated carbonyl compounds are valuable for synthesizing perfluoroarenes. Aldol condensation with pentafluorophenyl-substituted enolates is a highly effective method for their synthesis. This study demonstrates that bis(pentafluorophenyl)boron enolates, featuring a pentafluorophenyl group, readily undergo aldol additions with aldehydes. Subsequent elimination of borinic acid yields α-pentafluorophenyl-substituted α,β-unsaturated carbonyl compounds. Experimental results highlight the crucial role of strong Lewis acidity at the boron center in both aldol addition and borinic acid elimination.journal articl
中国語における時間表現の統語的柔軟性と構造的要因 : 時間名詞と時間副詞の語順容認度判断
Full text link本研究は、中国語母語話者を対象として、時間名詞と時間副詞の語順に関する容認度を、単文と複文の2種類の文構造で比較検討した。その結果、時間表現の語順選好は、（1）時間表現内部の構造（広い時間名詞と具体的時間名詞の結合／分離）および（2）文構造の階層性（単文／複文）の2要因によって大きく左右されることが示された。単文においては、広い時間名詞と具体的時間名詞が結合している場合、主語の前後いずれの位置でも高く容認され、語順の柔軟性が確認された。一方、分離した形式では容認度が低下し、意味的に関連する要素が近接している方が、処理負荷が軽減されることが示唆された。また、複合的時間名詞では文頭位置でも自然に受け入れられ、「広範から具体へ」という時間範囲原則が保持されていた。複文においては、時間名詞は主語前後いずれにも許容されるが、時間副詞は主語後に強く制約され、主語前では著しく不自然と判断された。この結果は、時間名詞が談話的トピックとして文全体の時間枠を設定できるのに対し、時間副詞は動詞句を修飾する統語的要素として機能していることを示している。This study investigated the word order acceptability of time nouns and time adverbs in Chinese, focusing on native speakers’ judgments in simple and complex sentences. The results showed that preferences for temporal expressions were shaped by two main factors: (1) the internal structure of the temporal phrase, whether broad and specific time expressions are combined or separated, and (2) the hierarchical structure of the sentence (simple vs. complex). In simple sentences, combinations of broad and specific time nouns were highly acceptable in both pre- and post-subject positions, revealing syntactic flexibility. In contrast, separated time expressions were less acceptable, suggesting that semantic proximity facilitates processing. Complex time noun phrases were equally acceptable in both positions, supporting the “broad-to-specific” temporal range principle. In complex sentences, time nouns remained acceptable in both positions, whereas time adverbs were strongly confined to the post-subject position. This contrast reflects a functional difference: time nouns can set the temporal frame of an event as a discourse topic, while time adverbs primarily modify the verb phrase. Overall, word order preferences in Chinese temporal expressions result from the interaction between syntactic configuration and discourse structure rather than from mere surface-level flexibility.departmental bulletin pape
High-Pressure Synthesis of Silicon-Rich Chromium Silicides: MoSi2-Type CrSi2 and PdGa5-Type CrSi5 with a Si Network
No full textTwo novel chromium silicides, MoSi2-type CrSi2 and PdGa5-type CrSi5, were successfully synthesized under high-pressure and high-temperature (HPHT) conditions at 12 GPa and 600 °C. The “missing” MoSi2-type CrSi2, which was theoretically predicted to be a stable phase of chromium disilicide, was experimentally obtained for the first time, and adopted a tetragonal I4/mmm structure with a = 3.09422(2) Å and c = 7.54051(5) Å. The crystal structure of MoSi2-type CrSi2 differs from that of ambient-pressure phase CrSi2-type CrSi2 in the stacking of close-packed layers. HPHT in situ XRD experiments suggest that the stacking transition in CrSi2 involves a diffusion-promoting liquid phase. PdGa5-type CrSi5, crystallizing in the I4/mcm structure with a = 5.99998(8) Å and c = 9.2363(2) Å, represents the most Si-rich compound among the reported transition-metal silicides. Its formation was confirmed by HPHT in situ XRD, and DFT calculations revealed that its enthalpy was lower than those of the other phases under high pressure. The structure contains covalently bonded Si–Si networks forming tunnel-like frameworks, reminiscent of clathrate architectures. These findings suggest the potential of exploring a novel class of silicon-rich transition-metal silicides and demonstrate that high-pressure synthesis is a powerful strategy for expanding the structural diversity of transition-metal silicides.journal articl
Improved dopant fraction variance estimation in statistical ALCHEMI based on correct error propagation rule
No full textThis report revisits the statistical atom location by channeling enhanced microanalysis method, correcting the dopant site occupancy error by applying an appropriate error propagation rule. A revised equation for calculating the uncertainty in the determined dopant fractions is proposed. The revised equation is expected to correct the uncertainty in the determined dopant fractions, which is particularly significant in cases of low dopant concentrations and variable dopant occupancies across inequivalent host atomic sites. The approach is validated using Eu-doped Ca2SnO4 as a typical model system.journal articl
Synthesis of Diazatricyclic Molecules via Intramolecular Cycloaddition of Azomethine Ylides
No full textDiazatricyclic molecules were synthesized via a modular approach. Starting from allylglycinol and amino acids, 2-ketopiperazines bearing an alkene unit were prepared. Upon heating with aldehydes, these 2-ketopiperazines generated azomethine ylides, which underwent intramolecular cycloaddition to construct the tricyclic core. The synthesis was completed in five or eight steps, with three or four substituents introduced in a modular fashion, respectively.journal articl
