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Synthesis and Crystal Structure Determination of 4’,9’,4”,9”-Tetra-t-Butyl- 1’,6’,1”,6”-Tetramethoxy-2,5-Dithia[3.3] Metabiphenylophane

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Crystal Structure Theory and Applications 2016年第3期5卷 56-62页

作者： Tetsuji Moriguchi Tatsuya Egami Daisuke Yakeya Venkataprasad Jalli kenji yoza Akihiko Tsuge Department of Applied Chemistry Faculty of Engineering Kyushu Institute of Technology Kitakyushu Japan Japan Bruker AXS K.K.3-9 Yokohama Japan

The title compound 4’,9’,4”,9”-tetra-tert-butyl-1’,6’,1”,6”-tetramethoxy-2,5-dithia[3.3] metabiphenylophane was synthesized as a calixarene like large-sized metacyclophane from the corresponding 3,3’-bis(chloromethyl)-5,5’-bis(1,1-dimethylethyl)-2,2’-dimethoxy-1,1’-biphenyl and 3,3’-bis (mercaptomethyl)-5,5’-bis(1,1-dimethylethyl)-2,2’-dimethoxy-1,1’-biphenyl via an intermolecular condensation reaction. The compound was characterized using 1H NMR spectroscopy and mass spectrometry. Its exact conformational structure was determined via single crystal X-ray diffraction analysis. The compound has quite strained 1,2-alternate like structure because of its two high dihedral angled and rigid biphenyl parts in the crystal. The crystal includes the two isomers as two different 1,2-alternate like conformers, and the ratio of the two isomers is 78:22.

关键词： Crystal Structure Metabiphenylcyclophane 1 2-Alternate Conformers

Syntheses, Crystal Structure and Photoluminescence Properties of Piperidinium Tetrakis (1,3-Diphenyl-1,3-Propanedionato) Europate(III) Complex and Its Two Different Crystals

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Crystal Structure Theory and Applications 2017年第4期6卷 57-66页

作者： Tetsuji Moriguchi Naoya Kitou Daisuke Yakeya Akihiko Tsuge kenji yoza Venkataprasad Jalli Department of Applied Chemistry Faculty of Engineering Kyushu Institute of Technology Kitakyushu Japan Japan Bruker AXS K.K. Yokohama Japan Sankar Foundation Research and Development Division Visakhapatnam India

Treatment of 1,3-diphenyl-1,3-propanedione 1a with europium (III) chloride in the presence of piperidine results in the halide ligands exchange giving newly piperidinium tetrakis (1,3-diphenyl-1,3-propanedionato)europate(III) complex 2a. The complex was characterized by 1H-NMR, positive FAB-mass, and Elemental Analysis. The exact molecular structure of 2a was determined by single crystal X-ray diffraction with the monoclinic space group Cc (centrosymmetric, No.13). The large cavity sizes of the complex 2a facilitated the inclusion of water and benzene solvate molecules. The other two different crystals 2b, 2c having two water molecules and one benzene moleculewere obtained by the crystallization in different solvents and the exact molecular structures were determined by single crystal X-ray diffraction analysis with space groups P21/n (centrosymmetric, No.14), and P21/n (centrosymmetric, No.14), respectively. The eight coordinate structures of the complexes in the three crystals were slightly different due to the crystal packing and the existence of the solvent molecule(s). The photoluminescence studies indicated that four β-diketone ligands acted as strong antenna ligands and transferred the absorbed energy to europium (III) ion, consequently red luminescence was observed. These strong emissions wereattributed to the 5D0 → 7F2 transition of Europium (III) ions under UV excitation. The photoluminescence spectrum of the three crystals was almost same in solid as well as in solution.

关键词： Tetrakis Europium Complexes Luminescence β-Diketone Ligands

Estimation of TBR on the Gap Between Neighboring Blanket Modules in the DEMO Reactor

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Plasma Science and Technology 2013年第2期15卷 171-174页

作者： Youji SOMEYA kenji TOBITA Japan Atomic Energy Agency Rokkasyo-mura Kamikita-gun Aomori 039-3212 Japan

When one wants to simply estimate tritium breeding ratio （TBR）, the TBR may be reduced from a ＂local＂ TBR for the breeding zones of a blanket module by multiplying the breeder coverage （= the surface area of effective breeding region / the surface area of the first wall around plasma）. When blanket modules are arranged~ the gap between neighboring modules and the frames of the modules are regarded as nombreeding zones. On the other hand, neutrons scattered in the non-breeding zones can enter breeding zones, contributing to tritium production. This means that the estimation method mentioned above tends to underestimate TBR. In order to assess the scattering effect quantitatively, we carried out a three-dimensional Monte Carlo N-particle transport MCNP-5 calculation. It was found from the calculation that there is little decrease in TBR for gaps less than 4 cm when the blanket thickness is 70 cm. The result indicates that such a wide allowance of the gap will facilitate access of remote handling equipment for the replacement of blanket modules and improve access of diagnostics.

关键词： blanket tritium breeding ratio neutron scattering MCNP

Dynamic properties of a flexible metal-organic framework exhibiting a unique"picture frame"-like crystal morphology

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Nano Research 2021年第2期14卷 432-437页

作者： kenji Sumida Nao Horike Shuhei Furukawa Institute for Integrated Cell-Material Sciences(WPI-iCeMS) Kyoto UniversityYoshidaSakyo-kuKyoto 606-8501Japan Centre for Advanced Nanomaterials School of Physical SciencesUniversity of AdelaideSA 5005Australia

The precise control of the crystal morphology of metal-organic frameworks(MOFs)enables optimization of its adsorptive properties,as well as enables better integration within functional ***,the influence of such modifications on the dynamic properties of flexible MOFs is poorly understood Here,we report the synthesis of a series of Cu_(2)(bdc)_(2)(bpy)(bdc^(2-)=1,4-benzenedicarboxylate;bpy=4,4,-bipyridine)crystals having an unusual picture frame-like morphology that results from a restriction in the quantity of bpy pillars added to the reaction mixture during the intercalation of the Cu_(2)(bdc)_(2)(MeOH)_(2)*** width of the frames is found to correlate with the quantity of bpy,and importantly,causes the dynamic properties of the resulting Cu_(2)(bdc)_(2)(bpy)material to vary between rigid,elastic,and shape memory *** all,the results demonstrate the potential for the properties of MOFs to be optimized via subtle manipulations in the crystal morphology rather than changes in the overall material composition.

关键词： metal-organic frameworks morphology control framework flexibility shape-memory effect gas sorption

Approximate Solutions to the Hamilton-Jacobi Equations for Generating Functions

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Journal of Systems Science & Complexity 2020年第2期33卷 261-288页

作者： HAO Zhiwei FUJIMOTO kenji ZHANG Qiuhua Department of Astronautical Science and Mechanics Harbin Institute of TechnologyHarbin 150001China Department of Aeronautics and Astronautics Kyoto UniversityC3 Bldg.Kyotodaigaku-katsuraNishikyo-kuKyoto 615-8540Japan

For a nonlinear finite time optimal control problem,a systematic numerical algorithm to solve the Hamilton-Jacobi equation for a generating function is proposed in this *** algorithm allows one to obtain the Taylor series expansion of the generating function up to any prescribed order by solving a sequence of first order ordinary differential equations ***,the coefficients of the Taylor series expansion of the generating function can be computed exactly under a certain technical *** a generating function is found,it can be used to generate a family of optimal control for different boundary *** the generating function is computed off-line,the on-demand computational effort for different boundary conditions decreases a lot compared with the conventional *** is useful to online optimal trajectory generation *** examples illustrate the effectiveness of the proposed algorithm.

关键词： Generating functions Hamilton-Jacobi equations optimal control Taylor series expansion two-point boundary-value problems

Electron transfer governed by light-matter interaction at metal-semiconductor interface

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npj Computational Materials 2020年第1期6卷 1628-1635页

作者： kenji Iida Masashi Noda Department of Theoretical and Computational Molecular Science Institute for Molecular ScienceMyodaijiOkazaki 444-8585Japan Center for Computational Sciences University of Tsukuba1-1-1 TennodaiTsukuba 305-8577Japan

The photoexcitation of heterostructures consisting of metallic nanoclusters and a semiconductor has been extensively investigated in relation to interests in photocatalysis and optical *** optoelectronic functions of the heterostructures originate from localized surface plasmon resonance,which can induce electron and resonance energy *** it is well known that photoinduced electronic interaction between a metallic nanocluster and a semiconductor is responsible for the resonance energy transfer,the electron transfer associated with the photoinduced electronic interaction has not been *** this paper,we elucidate the photoexcitation dynamics of a silver nanocluster/TiO_(2) heterostructure using an original first-principles computational approach that explicitly deals with light–matter *** is shown that the photoinduced silver–TiO_(2) electronic interaction causes excited electrons to be directly transferred from the silver nanocluster to the TiO2 layer without passing through the conduction band of the silver nanocluster.

关键词： silver interaction transfer

The thermal conductivity of the Earth's core and implications for its thermal and compositional evolution

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National Science Review 2021年第4期8卷 18-20页

作者： kenji Ohta Kei Hirose Department of Earth and Planetary Sciences Tokyo Institute of Technology Earth-Life Science Institute Tokyo Institute of Technology Department of Earth and Planetary Science The University of Tokyo

The thermal conductivity of iron alloys is a key to understanding the mechanism of convection in the Earth’s liquid core and its thermal history. The Earth’s magnetic field is formed by a dynamo action that requires...

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NOVEL SYNTHESIS OF POLYARYLENESULFONIUM CATIONS THROUGH A MULTI-ELECTRON TRANSFER PROCESS

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Chinese Journal of Polymer Science 1998年第2期16卷 106-116页

作者： TSUCHIDA Eishun MIYATAKE kenji Department of Polymer Chemistry Advanced Research Institute for Science and Engineering Waseda University Takyo 169 JapanDepartment of Polymer Chemistry Advanced Research Institute for Science and Engineering Waseda University Takyo 169 Japan

The oxidative polymerization of aryl sulfoxides provides a novel polysulfo-nium compound, poly(methylsulfonio-1,4-phenylenethio-1,4-phenylene cation) in quantita-tive yield. The polymerization proceeds efficiently in an acidic solution under atmosphericconditions. Oxygen, chemical and electrochemical oxidations are available. Vanadyl acety-lacetonate and cerium ammonium nitrate act as an effective catalyst for the oxygen ox-idative polymerization. The polymerization mechanism involves multielectron oxidation ofthe sulfides followed by successive electrophilic substitution. The resulting polyarylenesul-fonium cations are useful as a soluble precursor for the synthesis of high molecular weight(M_w>10~5) poly(thio arylne)s.

关键词： Oxidative polymerization Multi-electron transfer Sulfonium cation Poly(thio phenylene)

High-frequency magnetic characteristics of Fe-Co-based nanocrystalline alloy films

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Science China(Technological Sciences) 2010年第6期53卷 1501-1506页

作者： HIHARA Takehiko SUMIYAMA kenji Department of Materials Science and Engineering Nagoya Institute of TechnologyNagoya 466-8555Japan

Magnetically soft Fe-Co-based nanocrystalline alloy films were produced by two preparation methods:One using a new energetic cluster deposition technique and another using a conventional magnetron sputtering *** structural,static magnetic properties and high-frequency magnetic characteristics were *** the energetic cluster deposition method,by applying a high-bias voltage to a substrate,positively charged clusters in a cluster beam were accelerated electrically and deposited onto a negatively biased substrate together with neutral clusters from the same cluster source,to form a high-density Fe-Co alloy cluster-assembled film with good high-frequency magnetic *** the conventional magnetron sputtering method,only by rotating substrate holder and without applying a static inducing magnetic field on the substrates,we produced Fe-Co-based nanocrystalline alloy films with a remarkable in-plane uniaxial magnetic anisotropy and a good soft magnetic *** obtained Fe-Co-O,Fe-Co-Ti-N,and Fe-Co-Cr-N films all revealed a high real permeability exceeding 500 at a frequency up to 1.2 *** makes Fe-Co-based nanocrystalline alloy films potential candidates as soft magnetic thin film materials for the high-frequency applications.

关键词： Fe-Co-based nanocrystalline alloy films high-frequency characteristics energetic cluster deposition magnetron sputtering substrate rotation