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Cyclic oligourea synthesized from CO_(2):Purification,characterization and properties

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Green Energy & Environment 2022年第3期7卷 477-484页

作者： Ruhui Shi Haiyang Cheng Hongxiang Li Peixuan Wu Chao Zhang masahiko arai Fengyu Zhao State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesNo.5625 Renmin Rd.Changchun130022China University of Science and Technology of China No.96 Jinzhai Rd.Hefei230026China Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesNo.5625 Renmin Rd.Changchun130022China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesNo.5625 Renmin Rd.Changchun130022China

Carbon dioxide(CO_(2)) as a sustainable resource instead of toxic reagents has attracted considerable attention in synthesis of chemicals and polymeric ***,a kind of cyclic oligourea was synthesized via polycondensation of CO_(2) with 4,7,10-trioxa-1,13-tridecanediamine(TTD)followed by effective separation and purification *** developed an efficient separation strategy in which the linear oligourea molecules were selectively transformed to macromolecular polyurea molecules by a reaction of the–NH_(2) end group with 4,4’-diphenylmethane diisocyanate(MDI),followed by separation from cyclic oligourea using selected *** structure and physicochemical properties were confirmed by MALDI-TOF mass spectra,NMR,Cryo-EM,thermal analysis and solubility *** well-defined cyclic oligourea was produced with a high purity(99.4%)and the average-number molecular weight(Mn)of 1040 *** is semi-crystalline in structure with a melting point of 106℃and glass transition point of-10℃.The cyclic oligourea presented characteristically difference to its linear *** work provides a new member to cyclic polymer family.

关键词： materials separation purity

Carbon Dioxide as a Chemical Building Block and a Reaction Promoter/Controller

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Carbon Dioxide as a Chemical Building Block and a Reaction P...

Synthesis of powdered silver nanoparticles using hydrogen in aqueous medium

中国化学会·第一届全国二氧化碳资源化利用学术会议

作者： masahiko arai State Key Laboratory of Electroanalytical Chemistry Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Carbon dioxide is one of unsustainable substances that should be reduced or eliminated in the design, manufacture and use of chemical products. The utilization of CO in synthetic reactions contributes to the design of green sustainable chemical processes and has been investigated so far for several chemical reactions of practical importance. A few examples using CO as a chemical building block will be presented, such as the production of glycerol carbonate from glycerol and urea, in which glycerol is a byproduct in biomass conversion to fuels and urea is produced from CO, and the production of N, N-dimethylaniline via selective N-methylation of N-methylaniline by CO and H. The glycerol carbonate production via urea is one of indirect CO fixation reactions. Those reactions are multiphase reactions using conventional heterogeneous catalysts. In addition to the role of CO as a chemical building brock, it may act as a reaction promoter/controller in liquid phase reactions in spite of its inert nature. Some pressure is required for CO to dissolve into the liquid phases, in which the dissolved CO molecules may interact with reacting species(substrates, intermediates, catalysts), changing their reactivity, and the dissolution of CO assists the dissolution of coexisting gaseous reactants like H and O. The presence of dense phase CO may enhance the reaction rate and control the product selectivity of the liquid phase reactions. A few examples will be presented, including selective hydrogenation of carbonyl, nitro, and nitrile compounds with conventional supported metal catalysts and hydrogen production via photocatalytic water splitting with titanium dioxide powder. In hydrogenation of nitrobenzene, for instance, the desired product of aniline is obtained in 100% selectivity at any conversion level in the presence of CO.

关键词： carbon dioxide chemical building block carbonate synthesis N-methylation reaction promoter hydrogenation

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Particuology 2012年第1期10卷 140-143页

作者： Kushal D. Bhatte Krishna M.Deshmukh Yogesh P.Patil Dinesh N.Sawant Shin-Ichiro Fujita masahiko arai Bhalchandra M.Bhanage Department of Chemistry Institute of Chemical Technology Chemical Process Engineering Divison Graduate School of EngineeringHokkaido University

Environmentally benign one-pot protocol is used in the synthesis of silver nanoparticles （AgNPs） in powder form, involving the reduction of silver nitrate in the presence of fully hydrolyzed polyvinyl alcohol （PVA） as stabilizer by hydrogen （H2） as reducing agent in aqueous medium. Fully hydrolyzed biodegradable PVA has extremely low cytotoxicity, making it a favorable stabilizer from green perspective. In the present methodology, essentially naked silver nanoparticles are obtained in good yield. The prepared sil- ver nanoparticles were characterized by TEM, XRD, EDAX, UV-Vis spectroscopy and DLS histogram, and studied for its activity as a recyclable catalyst for synthesis of different enaminones.

关键词： Silver nanoparticlesAqueous mediaHydrogenCatalysisEnaminones synthesis

Developments and Applications of Supported Liquid Phase Catalysts

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Developments and Applications of Supported Liquid Phase Cata...

Layered double hydroxide-like Mg_3Al_(1–x)Fe_x materials as supports for Ir catalysts: Promotional effects of Fe doping in selective hydrogenation of cinnamaldehyde

中国化学会第九届全国络合催化学术讨论会

作者： Shin-ichiro Fujita masahiko arai Division of Chemical Process Engineering Graduate School of Engineering Hokkaido UniversitySapporo 060-8628Japan Division of Chemical Process Engineering Graduate School of Engineering Hokkaido UniversitySapporo 060-8628Japan

＜正＞It is of practical importance to use heterogeneous catalytic reactions in organic synthesis for easy catalyst - product separation and catalyst recovery and recycling and various techniques are applicable to heterogenize the catalytic reaction systems. When an organometallic catalyst is used, a liquid - liquid biphasic system is useful and easy to prepare and handle. In many cases, water and

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Chinese Journal of Catalysis 2018年第5期39卷 988-996页

作者： Weiwei Lin Haiyang Cheng Xiaoru Li Chao Zhang Fengyu Zhao masahiko arai State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina

Supported Ir catalysts were prepared using layered double hydrotalcite‐like materials,such as Mg3Al1-xFex,containing Fe and Al species in varying amounts as *** Ir catalysts were applied for the selective hydrogenation of cinnamaldehyde(CAL).When x was changed from 0(Ir/Mg3Al)to 1(Ir/Mg3Fe),the rate of CAL hydrogenation reached a maximum at approximately x=0.25,while the selectivity to unsaturated alcohol,i.e.,cinnamyl alcohol,monotonously increased from 44.9%to 80.3%.Meanwhile,the size of the supported Ir particles did not change significantly with x,remaining at 1.7-0.2 nm,as determined by transmission electron *** chemical state of Ir and Fe species in the Ir/Mg3Al1-xFex catalysts was examined by temperature programmed reduction by H2 and X‐ray photoelectron *** surface of the supported Ir particles was also examined through the in‐situ diffuse reflectance infrared Fourier‐transform of a probe molecule of *** the basis of these characterization results,the effects of Fe doping to Mg3Al on the structural and catalytic properties of Ir particles in selective CAL hydrogenation were *** significant factors are the electron transfer from Fe2+in the Mg3Al1–xFex support to the dispersed Ir particles and the surface geometry.

关键词： Ir catalyst Layered double hydroxide Fe doping Support effect Selective hydrogenation Cinnamaldehyde

Exploring the novel role of oligodendrocyte precursor cells in phagocytosis:beyond myelinogenesis

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Neural Regeneration Research 2025年第2期20卷 473-474页

作者： Gen Hamanaka Ken arai Neuroprotection Research Laboratories Departments of Radiology and NeurologyMassachusetts General Hospital and Harvard Medical SchoolCharlestownMAUSA

Roles of oligodendrocyte precursor cells in the central nervous system:Oligodendrocyte precursor cells(OPCs)have long been recognized for their critical role as precursors to oligodendrocytes,the primary myelin-producing *** precursors,OPCs mature and differentiate into oligodendrocytes,which contribute significantly to the formation of myelin sheaths around *** myelination,which is critical for the conduction of salutatory nerve impulses in the cerebral white matter,underscores the classical role of oligodendrocytes in central nervous system(CNS)***,because oligodendrocytes are differentiated cells that cannot proliferate.

关键词： critical system conduction

溴化四丁铵催化苯乙烯一步合成苯乙烯环状碳酸酯

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高等学校化学学报 2006年第8期27卷 1522-1525页

作者：孙建敏王亚丽屈学俭蒋大振肖丰收藤田进一郎荒井正彦吉林大学化学学院无机与材料化学系长春130012 北海道大学工学部

以溴化季铵盐为催化剂,通过苯乙烯的环氧化和CO2的加成反应一步直接合成出苯乙烯环状碳酸酯,详细考察了催化剂的用量、氧化剂的种类、反应温度、反应时间和CO2压力等因素对反应主产物收率的影响.结果表明,以溴化四丁铵为催化剂,于80℃和... 详细信息

以溴化季铵盐为催化剂,通过苯乙烯的环氧化和CO2的加成反应一步直接合成出苯乙烯环状碳酸酯,详细考察了催化剂的用量、氧化剂的种类、反应温度、反应时间和CO2压力等因素对反应主产物收率的影响.结果表明,以溴化四丁铵为催化剂,于80℃和1 MPa CO2下反应6 h,环状碳酸酯的收率达到38%,这是季铵盐阳离子和亲核性阴离子协同催化的结果.

关键词：苯乙烯环状碳酸酯一步合成苯乙烯二氧化碳溴化季铵盐

Inelastic constitutive equation of plasma-sprayed ceramic thermal barrier coatings

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 161-168页

作者： Masayuki arai Materials Science Research Laboratory Central Research Institute of Electric Power Industry

Ceramic thermal barrier coatings （TBCs） are a very important technology for protecting the hot parts of gas turbines （GTs） from a high-temperature environment. The coating stress generated in the operation of GTs brings cracking and peeling damage to the TBCs. Thus, it is necessary to evaluate precisely such coating stress in a TBC system. We have obtained a stress-strain curve for a freestanding ceramic coat specimen peeled from a TBC coated substrate by conducting the bending test. The test results have revealed that the ceramic coating deforms nonlinearly with the applied loading. In this study, an inelastic constitutive equation for the ceramic thermal barrier coatings deposited by APS is developed. The obtained results are as follows：（1） the micromechanics-based constitutive equation was formulated with micro crack density formed at splat boundary, and （2） it was shown that the numerical results for a nonlinearly deformed beam simulated by the developed constitutive equation agreed with the experimental results obtained by cantilever bending tests.

关键词： Inelastic constitutive equation Thermal barrier coating Gas turbine Micromechanics

How to Transmit Disaster Information Effectively:A Linguistic Perspective on Japan’s Tsunami Warnings and Evacuation Instructions

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International Journal of Disaster Risk Science 2013年第3期4卷 150-158页

作者： Kyoko arai Faculty of Business Administration Toyo UniversityTokyo 112-8606Japan

When the disastrous tsunamis hit East Japan on 11 March 2011, the hi-tech information transmission system that is the pride of Japan was unable to send out the Tsunami Warnings effectively;many lives were lost as a result. Subsequently, the Japan Meteorological Agency(JMA) set up a committee of experts to improve the overall system. Last year as a result of their meetings, a report on The Improvement of the Information Text for the Tsunami Warnings was announced. The changes are, however, problematic from the linguistics perspective as the committee did not include any experts in the field. This study examines a range of recordings of the Tsunami Warnings and the Evacuation Instructionsi given for the East Japan tsunami disaster from the perspective of linguistics, especially pragmatics, whose main objective is to discover how recipients interpret verbal messages. The aim of this article is to propose further improvement to the transmission system of Tsunami Warnings and Evacuation Instructions. This study also emphasizes the necessity and importance of reexamining the overall disaster information transmission issue in Japan, from the linguistics perspective.

关键词： disaster Japan recording