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Developement of Spherical Polyurethane Beads

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复旦学报（自然科学版） 2005年第5期44卷 819-820页

作者： k. maeda H. Ohmori H. Gyotoku Sanyo Chemical Industries Ltd. 11-1 Ikkyo Nomoto-choHigashiyama-kuKyotoJapanSanyo Chemical Industries Ltd. 11-1 Ikkyo Nomoto-choHigashiyama-kuKyotoJapanSanyo Chemical Industries Ltd. 11-1 Ikkyo Nomoto-choHigashiyama-kuKyotoJapan

We established a new method to produce the spherical polyurethane beads which have narrower distribution of particle size. This narrower distribution was achieved by the polyurethane prepolymer which contains ketimine as a blocked chain-extending agent. Firstly, the prepolymer is dispersed into the aqueous solution containing surfactant. Secondaly, water comes into the inside of prepolymer as oil phase. Thirdly, ketimine is hydrolyzed to amine, and amine reacts with prepolymer immediately to be *** spherical polyurethane beads are very suitable for automotive interior parts especially for instrument panel cover sheet producing under the slush molding method, because of good process ability, excellent durability to the sunlight and mechanical properties at low temperature. See Fig. 1 ,Fig. 2 and Fig. 3 (Page 820).

关键词：聚亚安酯球形珠酮亚氨有限分布封闭环

Computer-controlled ultra high voltage amplifier for dielectric elastomer actuators

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Biomimetic Intelligence & Robotics 2024年第1期4卷 14-23页

作者： Ardi Wiranata Zebing Mao Yu kuwajima Yuya Yamaguchi Muhammad Akhsin Muflikhun Hiroki Shigemune Naoki Hosoya Shingo maeda Department of Mechanical and Industrial Engineering University of Gadjah MadaYogyakarta 55281Indonesia Department of Mechanical Engineering Tokyo Institute of TechnologyTokyo 152-8550Japan Department of Engineering and Science Shibaura Institute of TechnologyTokyo 135-8548Japan Department of Electrical Engineering Shibaura Institute of TechnologyTokyo 135-8548Japan Department of Engineering Science and Mechanics Shibaura Institute of TechnologyTokyo 135-8548Japan Living Systems Materialogy(LiSM)Research Group International Research Frontiers Initiative(IRFI)Tokyo Institute of TechnologyYokohama 226-8501Japan

Soft robotics is a breakthrough technology to support human-robot *** soft structure of a soft robot can increase safety during human and robot *** of the promising soft actuators for soft robotics is dielectric elastomer actuators(DEAs).DEAs can operate silently and have an excellent energy *** simple structure of DEAs leads to the easy fabrication of soft *** simplicity combined with silent operation and high energy density make DEAs interesting for soft robotics *** actuation follows the Maxwell-pressure *** pressure produced in the DEAs actuation depends much on the voltage *** DEAs requires high voltage to gain an *** the power consumption of DEAs is in the milli-Watt range,the current needed to operate the DEAs can be *** commercially available DC-DC converters can convert the volt range to the kV *** order to get a voltage in the 2-3 kV range,the reliable DC-DC converter can be pricy for each *** problem hinders the education of soft actuators,especially for a newcomer laboratory that works in soft electric *** paper introduces an entirely do-it-yourself(DIY)Ultrahigh voltage amplifier(UHV-Amp)for education in soft ***-Amp can amplify 12 V to at a maximum of 4 kV *** a demonstration,we used this UHV-Amp to test a single layer of powdered-based *** strategy to build this educational type UHV-Amp was utilizing a Cockcroft-Walton circuit structure to amplify the voltage range to the kV *** its current state,the UHV-Amp has the potential to achieve approximately 4 *** created a simple platform to control the UHV-Amp from a personal *** near future,we expect this easy control of the UHV-Amp can contribute to the education of soft electric actuators.

关键词： Dielectric elastomer actuators Electric amplifier Soft actuators Soft robotics Soft actuator education

Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

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Green Energy & Environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

Superconducting joints using reacted multifilament MgB_(2)wires:A technology toward cryogen-free MRI magnets

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Journal of Magnesium and Alloys 2024年第1期12卷 159-170页

作者： Dipak Patel Akiyoshi Matsumoto Hiroaki kumakura Yuka Hara Toru Hara Minoru maeda Hao Liang Yusuke Yamauchi Seyong Choi Jung Ho kim Md Shahriar A.Hossain School of Mechanical and Mining Engineering The University of QueenslandSt LuciaQueensland 4072Australia National Institute for Materials Science(NIMS) 1-2-1 SengenTsukubaIbaraki 305-0047Japan Department of Electrical Engineering and kangwon High Magnetic Field Center Institute of Quantum Convergence TechnologyKangwon National UniversityGangwon 24341Republic of Korea Australian Institute for Bioengineering and Nanotechnology(AIBN) The University of QueenslandSt LuciaQueensland 4072Australia Department of Materials Process Engineering Graduate School of EngineeringNagoya UniversityNagoyaAichi 464-8603Japan Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongNorth WollongongNew South Wales 2500Australia

The development of superconducting joining technology for reacted magnesium diboride(MgB_(2))conductors remains a critical challenge for the advancement of cryogen-free MgB_(2)-based magnets for magnetic resonance imaging(MRI).Herein,the fabrication of superconducting joints using reacted carbon-doped multifilament MgB_(2)wires for MRI magnets is *** achieve successful superconducting joints,the powder-in-mold method was employed,which involved tuning the filament protection mechanism,the powder compaction pressure,and the heat treatment *** fabricated joints demonstrated clear superconducting-to-normal transitions in self-field,with effective magnetic field screening up to 0.5 T at 20 *** evaluate the interface between one of the MgB_(2)filaments and the MgB_(2)bulk within the joint,serial sectioning was conducted for the first time in this type of superconducting *** serial sectioning revealed space formation at the interface,potentially caused by the volume shrinkage associated with the MgB_(2)formation or the combined effect of the volume shrinkage and the different thermal expansion coefficients of the MgB_(2)bulk,the filament,the mold,and the sealing *** findings are expected to be pivotal in developing MgB_(2)superconducting joining technology for MRI magnet applications through interface engineering.

关键词： Mg B2 superconducting joint MgB_(2)conductor MRI applications Cryogen-free magnet Persistent-mode operation

kisspeptin neuron,a key player in mammalian reproduction

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Kisspeptin neuron,a key player in mammalian reproduction

γ-Butyrolactone Synthesis from Allylic Alcohols Using the CO_(2)Radical Anion

中国畜牧兽医学会动物繁殖学分会第十五届学术研讨会

作者： Tsukamura,H. maeda,k.-I Graduate School of Bioagricultural Sciences Nagoya UniversityNagoya 464-8601Japan

kisspeptin(first named metastin) was found as a product of the kissl gene and identified as an endogenous ligand for GPR54 in *** evidence suggests that kisspeptin-GPR54 signaling has been implicated to play a key role in reproductive function via stimulation of gonadotropin-releasing hormone(GnRH) release in mammalian *** previous studies revealed that endogenous kisspeptin is responsible for normal estrous cyclicity and induction of luteinizing hormone(LH) surge in female rats,suggesting that kisspeptin is involved in regulating tonic(pulse-mode) and cyclic(surge-mode) GnRH/LH release.

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Precision Chemistry 2024年第3期2卷 88-95页

作者： Saeesh R.Mangaonkar Hiroki Hayashi Wataru kanna Suvankar Debbarma Yu Harabuchi Satoshi maeda Tsuyoshi Mita Institute for Chemical Reaction Design and Discovery(WPI-ICReDD) Hokkaido UniversitySapporoHokkaido 001-0021Japan JST ERATO Maeda Artificial Intelligence in Chemical Reaction Design and Discovery ProjectSapporoHokkaido 060-0810Japan Department of Chemistry Faculty of ScienceHokkaido UniversitySapporoHokkaido 060-0810Japan Research and Services Division of Materials Data and Integrated System(MaDIS) National Institute for Materials Science(NIMS)TsukubaIbaraki 305-0044Japan

γ-Butyrolactone structures are commonly found in various natural products and serve as crucial building blocks in organic ***,the development of methods for synthesizingγ-butyrolactones has garnered significant interest within the organic synthesis *** this study,we present a direct and highly efficient approach for the synthesis ofγ-butyrolactones from allylic ***,this study represents the first instance ofγ-butyrolactone synthesis initiated by radical hydrocarboxylation using CO_(2)^(•–),generated from metal formates,followed by *** two-step process is achieved through the synergistic interaction of photoredox and hydrogen atom transfer(HAT)catalysis,resulting in the production ofγ-butyrolactones with exceptional ***,when employingα,α-diaryl allylic alcohol derivatives as substrates,the reaction involves 1,2-aryl migration,which occurs concomitantly with CO_(2)^(•–)addition,leading to the formation of 4,5-substituted lactones in a good *** artificial force induced reaction(AFIR)method identified the preferred 1,2-aryl migration pathway along with potential byproduct pathways,in which the targeted 1,2-migration was found to be the most plausible pathway.

关键词： CO_(2) lactone radical photoredox visible light carboxylation calculation DFT

Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?

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Journal of Forestry Research 2024年第2期35卷 209-221页

作者： Antônio Carlos Vargas Motta Shizuo maeda Valdécio dos Santos dos Santos Rodrigues Tamires Maiara Ercole Stephen Arthur Prior Ana Elisa Lyra Brumat Amanda Pacheco Cardoso Moura Julierme Zimmer Barbosa João Bosco Vasconcellos Gomes Department of Soil Sciences and Agriculture Engineering Federal University of ParanáR.dos Funcionários1540.CuritibaParanáCEP 80035‑050Brazil Brazilian Agricultural Research Company Embrapa FlorestasEstr.da Ribeira–Br‑476Km 111–Parque Monte Castelo.ColomboParanáCEP 83411‑000Brazil United States Department of Agriculture‑Agricultural Research Service USDA-ARS National Soil Dynamics Laboratory411 South Donahue DriveAuburnAL 36832USA Reforestation Remasa Rodovia PR 170–Km 522.BiturunaParanáCEP 84640‑000Brazil Federal Institute of Southeast of Minas Gerais R.Luz Interior360.Juiz de ForaMinas Gerais CEP 36030‑713Brazil

Needle chlorosis(NC)in Pinus taeda *** in Brazil becomes more frequent after second and third harvest rotation *** a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on *** were analyzed for various elements and *** soils had very low base levels(Ca^(2+),Mg^(2+)and k^(+))and P,suggesting a possible lack of multiple *** symptoms started at needle tips,then extended toward the needle base with *** flush needles had longer portions with YNC than second flush needles *** from the lower crown also had more symptoms along their length than those higher in the *** were similar to those reported for *** chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of *** in various parent soils in Brazil.

关键词： Nutritional deficiency Forest management Soil depletion Pine foliar analysis Needle chlorosis

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay k.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k JAMES Jintu kIM Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation