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Nanomanufacturing and Metrology 2024年第2期7卷 76-88页

作者： Motoya Yoshikawa Saeko Fujii Shotaro kadoya Tatsuya Sugihara masaki Michihata Satoru Tak.h.shi Department of Precision Engineering The University of TokyoHongo 7‑3‑1BunkyoTokyo 113‑8656Japan Department of Mechanical Engineering Osaka UniversityYamadaoka 2‑1SuitaOsaka 565‑0871Japan

This study proposes a model for the measurement of microscale liquid film thickness distribution using fluorescence *** interfacial conditions between the tool and the workpiece in mechanical machining are important for understanding these phenomena and *** this study,indentation tests with transparent tools were used to observe interfaces;however,it was challenging to obtain the signal from a thin fluorescent liquid film on smooth and steeply inclined ***,fluorescence-based measurement,such as laser-induced fluorescence,was *** measure the absolute thickness of the thin fluorescent film,calibration of the measurement system is ***,a theoretical model was proposed considering the multiple reflections of excitation light and fluorescence at the inclined surface between the indenter and *** measuring the profile of the surface topography of the indented workpiece and comparing the results with those measured by a surface profiler,the validity of the proposed calibration method and the performance of this measurement system were *** measured surface profiles,including scratches of 2–4μm,were in good agreement,demonstrating the validity of the proposed method.

关键词： Laser-induced fluorescence(LIF) Thickness distribution In-situ measurement Lubricant Mechanical machining

非痴呆患者的记忆主诉预测未来的阿尔茨海默病的病理诊断

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世界核心医学期刊文摘（神经病学分册） 2005年第4期1卷 47-47页

作者： Jorm A.F. masaki k.h. Davis D.G. 姚庆和 Centre for Mental health Research Australian National University Canberra ACT 0200 Australia Dr

The validity of memory complaints as a predictor of Alzheimer disease (AD) was assessed in 237 Japanese- American men autopsied at ages 74 to 97 years. These men were free of dementia at the time memory complaints were assessed 1 to 11 years earlier. Memory complaints were found to predict the neuropathologic diagnosis of AD after adjusting for age, time to death, education, depression, and cognitive functioning.

关键词：阿尔茨海默病病理诊断认知功能病理学诊断死亡时间中评估

Aggregation-induced emission and thermally activated delayed fluorescence of 2,6-diaminobenzophenones

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Science China Chemistry 2018年第8期61卷 925-931页

作者： masaki Shimizu masaki Nakatani kenta Nishimura Faculty of Molecular Chemistry and Engineering Kyoto Institute of Technology

Exploration of novel organic luminophores that exhibit thermally activated delayed fluorescence(TADF) in the aggregated state is very crucial for advance of delayed luminescence-based applications such as time-gated bio-sensing and temperature *** report herein that synthesis, photophysical properties, molecular and crystal structures, and theoretical calculations of 2,6-bis(diarylamino)benzophenones. Absorption spectra in solution and calculations using density functional theory(DFT) method revealed that the optical excitation took place through intramolecular charge-transfer from one diarylamino moiety to an aroyl group. While the benzophenones did not luminesce in solution, the solids of the benzophenones emitted green light with moderate-to-good quantum yields. Thus, the benzophenones exhibit aggregation-induced emission. Based on the lifetime measurement, the green emission of the solids was found to include TADF. The emergence of the TADF is supported by the small energy gap between the excited singlet and triplet states, which was estimated by time-dependent DFT calculations. Thin films of poly(methyl methacrylate) doped by the benzophenones also showed green prompt and delayed fluorescence whose lifetimes were in the order of microseconds. Linear correlation between logarithm value of TADF lifetime and temperature was observed with the benzophenone in powder, suggesting that the benzophenones can serve as molecular thermometers workable under aqueous conditions.

关键词： donor-acceptor system delayed fluorescence temperature sensor

Photophysical properties of heteroaromatic ring-fused(di)benzosiloles

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Science China Chemistry 2011年第12期54卷 1937-1947页

作者： ShIMIZU masaki MOChIDA kenji kATOh masaki hIYAMA Tamejiro Department of Material Chemistry Graduate School of EngineeringKyoto University kyoto University katsura Current address:Research & Development Initiative Chuo University

Benzosiloles fused to heterocycles such as thiophene, benzothiophene, and benzofuran, and indole- and benzosilole-fused dibenzosiloles were prepared by palladium-catalyzed intramolecular coupling of the corresponding 2-（arylsilyl）aryl triflates in good to high yields. Molecular and crystal structures of 5,7-dihydro-5,5,7,7-tetrakis（1-methylethyl）bis[1]benzosilolo-[2,3-b：3＇, 2＇-d]thiophene, 6-methyl-12,12-diisopropyl-12h-indololo[3,2-b][1]silafluorene, and 5,5,11,11-tetraisopropyl-5,11h-benzosilolo[3,2-c]silafluorene were determined by X-ray diffraction analysis. The UV absorption spectra of the （di）benzosilole derivafives in cyclohexane red-shifted when compared to 1,1-diisopropyldibenzosilole, indicating that replacing a benzene ring of dibenzosilole by the heterocycles as well as fusion of indole and benzosilole moieties onto dibenzosilole narrowed the hOMO- LUMO gaps of the n-conjugation system. The thiophene-fused benzosiloles were faintly fluorescent in solution and in the solid state, whereas the dibenzosiloles exhibited luminescence with moderate and high quantum yields in cyclohexane and in microcrystals, respectively. In other words, aggregation-induced emission was observed for the dibenzosiloles. Notably, 5,5,11,1 1- tetraisopropyl-5,11h-benzosilolo[3,2-c]silafluorene in microcrystals exhibited violet fluorescence （λmax = 396 nm） with a quantum yield of 0.70. Density functional theory （DFT） calculations of the prepared （di）benzosiloles were also performed.

关键词： absorption benzosflole fluorescence silicon solid-state emission

Diagonal reflection symmetries and universal four-zero texture

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Chinese Physics C 2021年第4期45卷 87-97页

作者： masaki J.S.Yang Department of Physics Saitama UniversityShimo-okuboSakura-kuSaitama338-8570Japan

In this paper,we consider a set of new symmetries in the SM:diagonal reflection symmetries Rm_(u,v)^(*),R=m_(u,v),m_(d,e)^(*)=mde with R=diag(-1,1,1).These generalized CP symmetries predict the Majorana phases to beα_(2.3)/2-0π/*** of diagonal reflection symmetries implies a broken chiral U(1)po symmetry only for the first *** axion scale is suggested to be(θ_(u,d))~△GuT√m_(u,dm_(c,s))/v-10^(12)[GeV].By combining the symmetries with the four-zero texture,the mass eigenvalues and mixing matrices of quarks and leptons are reproduced *** scheme predicts the normal hierarchy,the Dirac phase ocp≈203°,and|ml|≈2.5 or 6.2[meV].In this scheme,the type-I seesaw mechanism and a given neutrino Yukawa matrix Y_(y)completely determine the structure of the right-handed neutrino mass M_(R).A u-y unification predicts the mass eigenvalues to be(M_(RI),M_(R2),M_(R3))=(O(10^(5)).O(10^(9)),O(10^(14))[Gev].

关键词： μ-t reflection symmetry four-zero texture generalized CP symmetry

A sulfur–microporous carbon composite positive electrode for lithium/sulfur and silicon/sulfur rechargeble batteries

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Progress in Natural Science:Materials International 2015年第6期25卷 612-621页

作者： Takuya Tak.h.shi masaki Yamagata Masashi Ishikawa Department of Chemistry and Materials Engineering Faculty of ChemistryMaterials and BioengineeringKansai University

Sulfur is an advantageous material as a promising next-generation positive electrode material for high-energy lithium batteries due to a high theoretical capacity of 1672 m A h g 1although its discharge potential is somewhat modest:ca.2 V vs Li/***,a sulfur positive electrode has some crucial problems for practical use,which are mainly attributed to the dissolution of its intermediate products in charge–discharge *** order to resolve the dissolution problem of lithium polysulfide,we attempted to synthesize a sulfur–microporous activated carbon(AC) composite positive ***,we have systematically researched the battery performance of sulfur–microporous AC positive electrode with variations of electrolytes as well as negative electrodes,and found its promising positive electrode performance for a nextgeneration rechargeable battery.

关键词： Sulfur Micropore Ionic liquid Silicon Lithium-ion battery

Controllable fabrication of carbon aerogels

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Rare Metals 2006年第z1期25卷 284-288页

作者： TANEMURA Sakae TANEMURA masaki SUZUkI kenzi Department of Environmental Technology & Urban Planning Nagoya Institute of Technology Showa-ku Nagoya 466-8555 Japan EcoTopia Science Institute Nagoya University Chikusa-ku Nagoya Japan

Nano-pore carbon aerogels were prepared by the sol-gel polymerization of resorcinol (1,3-dihydroxybenzene)(C6h4(Oh)2) with formaldehyde (hChO) in a slightly basic aqueous solution, followed by super-critical drying under liquid carbon dioxide as super-critical media and carbonization at 700 ℃ under N2 gas atmosphere. The key of the work is to fabricate carbon aerogels with controllable nano-pore structure, which means extremely high surface area and sharp pore size distribution. Aiming to investigate the effects of preparation conditions on the gelation process, the bulk density, and the physical and chemical structure of the resultant carbon aerogels, the molar ratio of R/C (resorcinol to catalyst) and the amount of distilled water were varied, consequently two different sets of samples, with series of R/C ratio and RF/W (Resorcinol-Formaldehyde to water, or the content of reactant) ratio, were prepared. The result of N2 adsorption/desorption experiment at 77 k shows that the pore sizes decreasing from 11.4 down to 2.2 nm with the increasing of the molar ratio of R/C from 100 to 400, and/or, the pore sizes decreasing from 3.8 down to 1.6 nm with the increasing of reactant content from 0.4 to 0.6.

关键词： resorcinol-formaldehyde aerogels carbon aerogels super-critical drying N2 adsorption/desorption

Grain refining in weld metal using short-pulsed laser ablation during CW laser welding of 2024-T3 aluminum alloy

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International Journal of Extreme Manufacturing 2019年第4期1卷 34-41页

作者： masaki kasuga Tomokazu Sano Akio hirose Division of Materials and Manufacturing Science Graduate School of EngineeringOsaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan

The 2024 aluminum alloy is used extensively in the aircraft and aerospace industries because of its excellent mechanical ***,the weldability of 2024 aluminum alloy is generally low because it contains a high number of solutes,such as copper(Cu),magnesium(Mg),and manganese(Mn),causing solidification *** high speed welding of 2024 aluminum alloy without the use of filler is achieved,the applicability of 2024 aluminum alloys will *** refining is one of the methods used to prevent solidification cracking in weld metal,although it has never been achieved for high-speed laser welding of 2024 aluminum alloy without ***,we propose a short-pulsed,laser-induced,grain-refining method during continuous wave laser welding without ***-on-plate welding was performed on a 2024-T3 aluminum alloy at a welding speed of 1 m min−1 with a single mode fiber laser at a wavelength of 1070 nm and power of 1 *** in and around the molten pool were irradiated with nanosecond laser pulses at a wavelength of 1064 nm,pulse width of 10 ns,and pulse energy of 430 *** grain-refinement effect was confirmed when laser pulses were irradiated on the molten *** grain-refinement region was formed in a semicircular shape along the solid–liquid *** of the vertical section indicate that the grain-refinement region reached a depth of 1 mm along the solid–liquid *** Vickers hardness test results demonstrated that the hardness increased as a result of grain refinement and that the progress of solidification cracking was suppressed in the grain refinement region.

关键词： 2024 aluminum alloy hot cracking laser welding grain refinement dendrite fragmentation short pulsed laser laser ablation

Organic fluorophores that emit ultraviolet light in the aggregated state

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Aggregate

Aggregate 2022年第2期3卷 22-32页

作者： masaki Shimizu Tsuneaki Sakurai Faculty of Molecular Chemistry and Engineering Kyoto Institute of TechnologyKyotoJapan

Ultraviolet(UV)-emissive organic light-emitting diodes(OLEDs)have attracted growing attention as future UV-lighting sources following *** design and development of highly efficient UV-emissive organic solids are essential for the advancement of *** herein are organic small molecules and polymers that exhibit UV emission in the aggregated state such as crystal,powder,and amorphous *** UV-emissive molecules are in principle limited to those whose photoluminescence(PL)maxima are less than 400 nm and whose PL quantum yields in the aggregated state,which are useful for evaluating the potential of solid-state emitters,are *** cases that electroluminescence(EL)studies are demonstrated,the emission maxima and external quantum efficiencies with the device structures are also *** exceptions are also included whose PL quantum yields are not reported,but UV-EL with an emission maximum of less than 400 nm is demonstrated.

关键词： conjugation light-emitting materials molecular design solid-state emission UV OLEDs

Reductive transformation of CO_2:Fluoride-catalyzed reactions with waste silicon-based reducing agents

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Chinese Journal of Catalysis 2017年第3期38卷 434-439页

作者： ken Motokura masaki Naijo Sho Yamaguchi Akimitsu Miyaji Toshihide Baba 东京工业大学材料和化工技术学院化工科学与工程系日本横滨226-8502

CO_2 is one of the most important ＂renewable＂ carbon *** transform CO_2 to useful organic compounds,we examined the reactivity of two model silicon-based ＂waste＂ materials,disilanes and metallic Si powder,as reducing *** these reactions,fluoride salts were found to be active catalysts：CO_2 was converted to formic acid at atmospheric pressure in the presence of h_2O as a proton source and the silicon-based reducing *** on in-situ NMR and kinetics analyses,a hydrosilane and penta-coordinate Si species are proposed as the reaction intermediate and active species,respectively.

关键词： Carbon dioxide Fluoride homogeneous catalysis Formic acid Disilane