Kyushu University Academic Staff Educational and Research Activities Database
List of Presentations
Kenji Kaneko Last modified date:2024.02.22

Professor / Structural Materials Engineering / Department of Materials Science and Engineering / Faculty of Engineering


Presentations
1. 7p-R-8 Observation of decagonal quasicrystals by the high-angle annular dark-field method II.
2. 7p-R-7 Observation of decagonal quasicrystals by the high-angle annular dark-field method.
3. Foreword to Feature Articles on the Recent Advances in Microstructural Research for Materials Development via Microscopy (7)-3D/4D Imaging-.
4. Kenji Kaneko, Three-dimensional characterization of various crystalline materials by electron microscopy, AMTC5, 2016.05, [URL], Nanoscale characterization plays a vital role in process, design and property of materials used in nanoscience and nanotechnology. Large numbers of papers have been published concerning nanoscale materials based on characterizations by electron microscopes displaying 2D images, which is not reflecting the true 3D morphologies or dispersions of the materials precisely, and authors had to correlate those 2D results with 3D physical properties of materials. Therefore, it is extremely important to learn the correlation between the 3D physical properties of materials and their sizes, structures, compositions, dispersions and morphologies. Recent development of fully-digitized and automated electron microscopes, both scanning electron microscope (SEM) and transmission electron microscope (TEM), as well as advancement of fast computers and commercial software let us achieve 3D information by electron microscopes. A 3D object can be reconstructed from a series of 2D images obtained from electron microscopes, either the combination of focus ion beam (FIB) and SEM via slice-sectioning (SS) or that of TEM and computed tomography (CT), to determine dispersion and morphology of the object in the order of nanometer.
In this talk, I will present recent results obtained from various crystalline materials obtained by TEM-CT and FIB-SEM-SS..
5. Kenji Kaneko, Three-dimensional characterization of various crystalline materials by electron microscopy Two dee or not two dee, that is the question!, NIMS Conference 2015, 2015.07, [URL], Nanoscale characterization plays a vital role in process, design and property of materials used in nanoscience and nanotechnology. Large numbers of papers have been published concerning nanoscale materials based on characterizations by electron microscopes displaying 2D images, which is not reflecting the true 3D morphologies or dispersions of the materials precisely, and authors had to correlate those 2D results with 3D physical properties of materials. Therefore, it is extremely important to learn the correlation between the 3D physical properties of materials and their sizes, structures, compositions, dispersions and morphologies. Recent development of fully-digitized and automated electron microscopes, both scanning electron microscope (SEM) and transmission electron microscope (TEM), as well as advancement of fast computers and commercial software let us achieve 3D information by electron microscopes. A 3D object can be reconstructed from a series of 2D images obtained from electron microscopes, either the combination of focus ion beam (FIB) and SEM via slice-sectioning (SS) or that of TEM and computed tomography (CT), to determine dispersion and morphology of the object in the order of nanometer.
In this talk, I will present recent results obtained from various crystalline materials obtained by TEM-CT and FIB-SEM-SS..
6. 金子 賢治, Three-dimensional nanostructural analysis of artificial pinning in coated conductors by electron tomography, The 15th IUMRS-International Conference in Asia (IUMRS-ICA 2014), 2014.09, In high temperature superconductors, artificial pinning centers (APCs) are intentionally introduced to pin the vortices effectively for compensation of the intrinsic field angle anisotropy and to improve Jc characteristics. APCs have been analyzed via various microscopic methods in detail, many of them are actually in 2D, which does not represent 3D nature of APCs. The nanostructural characterization of APCs in 3D (distribution, morphology, volume, etc.) are of worthwhile for further understanding and improvement of the superconducting properties, and hence for designing of future high temperature superconductors. Electron tomography, a combination of transmission electron microscopy and computed tomography, was therefore applied on APCs to acquire 3D information of them at nanoscale resolution. During my presentation, both three-dimensional electron tomography and actual application of it on artificial pinning centers in various dimension, will be presented..
7. 金子 賢治, Three-Dimensional Electron Tomography for Materials Science and Engineering, The 14th IUMRS-International Conference in Asia (IUMRS-ICA 2013), 2013.12, Currently, there are several “tomographic” methods available to acquire three-dimensional information of materials, and have been applied for various types of materials; three-dimensional atomic probe at atomic resolution, electron tomography via focused ion beam (FIB) method at submicron resolution, and electron tomography via (scanning) transmission electron microscopes, (S)TEM, at a few nanometer resolution. Three-dimensional electron tomography (3D-ET), a technique originally established in the field of life sciences, has been developed and applied for materials science and engineering, which is a useful technique for reconstructing an object from a series of projections acquired by a (S)TEM. In addition, every materials available in the world is actually in 3D and their properties are usually dealt in 3D, so that characterization of materials should also be dealt in 3D at micro- and nano-scale. Recent progress of fully-digitized and automated (S)TEM let us achieve 3D characterization for not only to determine the size and distribution of objects but also to provide information about the 3D morphology.
Five different types of information was achieved by 3D-ET: the morphological information of metallic nanoparticles decorated by supramolecules, the distribution of metallic nanoparticles within catalyst, the crystal habit of CeO2 for catalytic activities, the morphological transformation of GP zones due to plastic deformation, and morphology of precipitates within Al alloy.
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8. Kenji Kaneko, Electron Tomography for Materials Science and Engineering, International Conference on Electron Microscopy and XXXIV Annual Meeting of the Electron Microscope Society of India, 2013.07, [URL].
9. Hadi Razavi Khosroshahi, Xin Liu, Noritaka Saito, Kunihiko Nakashima, Kenji Kaneko, Effect of nano-sized particles on the mechanical properties of Y2O3, 8th International Forum on Advanced Materials Science and Technology, IFAMST 2012, Two types of TiO2/Y2O3 and ZrO2/Y2O3 composites were fabricated for enhancing the mechanical properties of Y2O3 ceramic. Results showed that ZrO2/Y2O3 composite dramatically increased the strength and toughness as 417 MPa and 4.4 MPa.m1/2, respectively..
10. T. Nishiyama, K. Yamada, Ryo Teranishi, Kenji Kaneko, T. Kato, T. Izumi, Y. Shiohara, Three-dimensional characterization of BaZrO3 precipitates in Y1-xGdxBa2Cu3O7-y prepared by TFA-MOD using STEM-tomography, 8th International Forum on Advanced Materials Science and Technology, IFAMST 2012, Y1-xGdxBa2Cu3O7-y film with BaZrO3 was fabricated on CeO2 buffered LaMnO3/ion beam assisted deposition MgO/Gd2Zr2O7/Hastelloy C276TM substrates by the trifluoroacetates metal organic deposition process, whose microstructural and elemental analyses were performed by transmission electron microscopy. Y1-xGdxBa2Cu3O7-y film with the thickness about 700 nm was found composed of c-axis oriented grains and large numbers of randomly oriented precipitates, such as (Y,Gd)2Cu2O5, CuO and BaZrO3. (Y,Gd)2Cu2O5 and CuO precipitates were heterogeneously dispersed in the Y1-xGdxBa2Cu3O7-y matrix with their sizes ranging between 100 and 200 nm, and BaZrO3 precipitates were uniformly dispersed with their sizes ranging between 10 and 20 nm. Electron tomography with elemental information was performed further to reveal the threedimensional information of BaZrO3 precipitates..
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14. Effect of holding temperature on microstructures and Jc properties of YBa2Cu3O7-X films fabricated by TFA-MOD method
K. Konya, K. Ootaguro, T. Nishiyama, R. Teranishi, T. Kiss, K. Yamada, K. Kaneko, M. Yoshizumi, T. Izumi.
15. Study of factors in joint resistance for GdBCO coated conductors
T. Watanabe, T. Kamata, T. Maebatake, R. Teranishi, T. Kiss, K. Yamada, K. Kaneko, M. Yoshizumi, T. Izumi.
16. J. S. Barnard, J. H. Sharp, Satoshi Hata, Masatoshi Mitsuhara, Kenji Kaneko, K. Higashida, 3-dimensional imaging of dislocation microstructures by electron beams, 2011 MRS Fall Meeting, 2012.12, We review the progress in the electron tomography of dislocation microstructures in the transmission electron microscope (TEM). Dislocation contrast is visible both in conventional TEM and scanning TEM (STEM) modes and, despite the complicated intensity variations, dislocation contrast can be isolated using computational filtering techniques prior to reconstruction. We find that STEM annular dark-field (STEM-ADF) imaging offers significant advantages in terms of dislocation contrast and background artifacts. We present several examples, both in semiconducting and metallic systems, illustrating the properties of 3D dislocations. We present the high-angle triple-axis (HATA) specimen holder where the diffraction condition can be chosen at will and dislocation tomograms of multiple reflections can be combined. 3D dislocations are analyzed in terms of dislocation density and dislocation nodal structures. Several avenues of study are suggested that may exploit the 3D dislocation data..
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40. Flux pinning properties of YBCO films with Sn compound addition by TFA-MOD method
Y. Masuda, Y. Miyanaga, R. Teranishi, K. Yamada, N. Mori, M. Mukaida, T. Kiss, M. Inoue, M. Yoshizumi, T. Izumi, K. Kaneko, S. Munetoh, [URL].
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43. Effect of cluster and precipitate on tensile property in Al-Mg-Si alloy,
K. Ikeda, K. Terada, S. Hata, H. Nakashima, K. Takata, M. Saga, J. Takahashi, K. Ushioda, K. Kaneko and M. Kikuchi,
ICAA12 at Pacifico Yokohama, Japan, [URL].
44. Analysis of yield strength for isothermal aged Al-Mg-Si alloys,
K. Takata, M. Saga, J. Takahashi, K. Ushioda, K. Ikeda, K. Terada, S. Hata, H. Nakashima, K. Kaneko and M. Kikuchi,
ICAA12 at Pacifico Yokohama, Japan, [URL].
45. Application of electron tomography for characterizing precipitate morphologies in Al alloys,
K. Kaneko
ICAA12 at Pacifico Yokohama, Japan, [URL].
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48. S. Sadamatsu, Masaki Tanaka, K. Higashida, Kenji Kaneko, Masatoshi Mitsuhara, Satoshi Hata, M. Honda, Crack tip dislocations observed by combining scanning transmission electron microscopy and computed tomography, 6th International Conference on Processing and Manufacturing of Advanced Materials - THERMEC'2009, Crack tip dislocations and dislocations introduced by three point-bending tests at high temperature are observed by combinating scanning transmission electron microscopy and computed tomography (STEM-CT). Commercially available P type (001) single crystal silicon wafers were employed. A series of STEM image was acquired from -60° to +60° in tilt range with 2° in tilt step. The diffraction vector was maintained close to g(hkl) = 220 during the acquisition by adjusting the [110] direction of the sample parallel to the tilt axis of the holder. Reconstructed images of dislocations revealed dislocation structures in three-dimension..
49. Visualization by 3D-ET method of precipitates in an Al-4.5Mg-0.7Mn-0.3Sc-0.2Zr alloy, [URL].
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59. Kenji Kaneko, Keisuke Sato, Zenji Horita, Koji Inoke, Characterization of precipitates by three-dimensional electron tomography, 6th Pacific Rim International Conference on Advanced Materials and Processing, PRICM 6, 2007.11, [URL], Structures and morphologies of Ge precipitates in an Al-Ge alloy were characterized by a combination of transmission electron microscopy and three-dimensional electron tomography. Faceting of the precipitates was clearly seen using transmission electron microscopy and varieties of precipitate morphologies were identified by three-dimensional electron tomography..
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62. Kenji Kaneko, Keisuke Sato, Zenji Horita and Koji Inoke, Characterization of precipitates by three-dimensional electron tomography, The 6th Pacific Rim International Conference on Advanced Materials and Processing, 2007.11, Structures and morphologies of Ge precipitates in an Al-Ge alloy were characterized by a combination of transmission electron microscopy and three-dimensional electron tomography. Faceting of the precipitates was clearly seen using transmission electron microscopy and varieties of precipitate morphologies were identified by three-dimensional electron tomography..
63. Ayumu Umemoto, Koichi Hayashi, Kyoko Hayano, Noritaka Saito, Kenji Kaneko, Kunihiko Nakashima, Effect of mo powder surface condition on fabrication of Mo-SiO2 functionally graded materials with slipcasting method, 2nd International Conference on Characterization and Control of Interfaces for High Quality Advanced Materials, and Joining Technology for New Metallic Glasses and Inorganic Materials, The conventional high intensity discharge lamps are made of Mo foil-sealing method, in which the Mo-metal of 30 μm thick is sandwiched by the fused silica envelope. The conventional high intensity discharge lamps therefore requires cooling system to reduce the thermal stress between Mo and fused silica during the switching operation and a long sealing zone is usually required to complete hermeticity, especially in high power devices, so that the production of compact high intensity discharge lamps has been a Herculean task. We show the invention of the new type of hermetically-sealed high intensity discharge lamps, made of Mo-SiO2 functionally graded material (FGM) as an electrode and a sealing component. In the case of high intensity discharge lamps with Mo-SiO2 FGM (FGM-Lamp), the thermal expansion coefficient between Mo and SiO2 is functionally graded so that it tolerates a large numbers of heating cycles, with no cooling system are required. Furthermore lamps survive without breakage. The W electrode is totally separated from the lamp envelope by the FGM, so that no leakage of the luminous elements or gases takes place, when a large gas pressure exists inside a lamp. In this paper, effects of Mo powder surface conditions on the fabrication of Mo-SiO 2 FGM have been investigated. Mo-SiO2 FGM with as-received Mo powder revealed that the Mo particles were homogenously distributed, which resulted in no microscopic compositional gradient. In contrast. Mo-SiO 2 FGM with pre-treated Mo powder provided a uniform gradient from the conductive part (Mo-rich phase) to the sealing part (amorphous silica)..
64. Yoichi Takeda, Naohiko Shimada, Kenji Kaneko, Kazuo Sakurai, Seiji Shinkai, Property of polysaccharide nano gel involves polyion complex consists of cationic polymer/ DNA, 55th SPSJ Annual Meeting, 2006.10, It is known to be hydrophobic as for the Polyion complex that consisits of DNA and the cation when it is equal compared with the cation/anion. On the other hand, when the DMSO solution of β glucan is dropped to water, the Nano gel that has the hydrophobic area internally is formed. We found that DNA and the cation complex be able to be involved in the Nano gel of Schizophyllan that one of β glucan for the first time in this research. Moreover, the application of CpG DNA delivery will be described..
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66. Yoshiyasu Kawasaki, Koji Neishi, Yuichi Miyahara, Katsuaki Nakamura, Kenji Kaneko, Michihiko Nakagaki, Zenji Horita, Application of severe torsion straining process for grain refinement of steel, 3rd International Conference on Nanomaterials by Severe Plastics Deformation, NanoSPD3, Severe torsion straining process (STSP) is a useful technique for grain refinement of metallic materials. With this process, a local heated zone is produced in a rod and one side of the rod is rotated with respect to the other so that torsion strain is introduced into the local heated zone. Severe straining is then achieved continuously throughout the rod by simultaneous rotation and longitudinal movement of the rod. Thus, the STSP is a continuous process and a die-less process for grain refinement. It is suggested that the STSP provide potential for commercialization. In this study, S45C steel rods with 12 mm in diameter were subjected to STSP. This process was conducted at a temperature of 923 K (650°C) with various ratios of rotation to longitudinal movement of a rod. Local heating was made using an induction coil and both sides of the local heated zone were cooled by water spray. Microscopy observation revealed that the initial grain size of ∼15 μm was reduced to ∼2 μm using the STSP..
67. Katsuaki Nakamura, Koji Neishi, Kenji Kaneko, Michihiko Nakagaki, Zenji Horita, Continuous grain refinement using severe torsion straining process, 3rd International Conference on Nanomaterials by Severe Plastics Deformation, NanoSPD3, This study presents a new rapid continuous process for grain refinement in metallic materials through severe plastic deformation (SPD). The new process, designated in this study the severe torsion straining process (STSP), is applicable to a wide range of alloys based on aluminum, magnesium and copper including carbon steel. This process consists of producing a local heated zone in a rod and cooling both sides of the heated zone by spray water while rotating one end with the other. Thus, torsion strain is introduced in the local heated zone. The STSP can be continuous because the straining is achieved while the rod is shifted along the longitudinal axis of die rod. Furthermore, the process requires no die, suggesting a potential for commercialization of grain refinement through SPD. In this study, STSP was applied to an Al-Mg alloy and a Mg-Al-Zn alloy. It is shown that STSP is effective for both alloys so that the grain size is reduced to ∼1.5 μm for the Al alloy and ∼0.9 μm for the Mg alloy. Tensile testing showed that the strength is increased with a minimal decrease in uniform elongation. There is a critical ratio between rotation speed and moving speed, which defines the feasibility of STSP operation without breaking the rod. The grain size tends to be lowered as the ratio is close to the critical value..
68. Munenori Numata, Shunichi Haraguchi, Tomohisa Fujisawa, Kenji Kaneko, Kazuo Sakurai, Seiji Shinkai, Creation of novel nanomaterials utilizing biomaterials based on natural polysaccharide-conjugated polymer complex, 55th SPSJ Annual Meeting, It is already known that β-1,3-glucans form a hydrophobic cavity within the helical superstructure, which is surrounded by hydrophilic side-glucoses or primary OH groups. This unique core-shell structure resembles that of cyclodextrins, which are well-established hosts for C60. Therefore, the fact encouraged us to pursue the possibility that β-1,3-glucans could act as a novel one-dimensional host for single-walled carbon nanotubes (SWNTs). As expected, β-1,3-glucans can interact with SWNTs to produce unique nanocomposites, in which SWNTs are entrapped within a one-dimensional hollow constructed by the helical superstructure of β-1,3-glucans. Moreover, various conductive polymers are also entrapped within the one-dimensional hollow to be arranged into the one-dimensional array. Since the surface is covered with β-1,3-glucans, the complex has potential to be bionanomaterials, where β-1,3-glucans act as an interface between the conjugated polymer and biologically important molecules. We tested this idea utilizing schizophyllan/conjugated polymer complex..
69. Koji Neishi, Akihiko Higashino, Yuichi Miyahara, Katsuaki Nakamura, Kenji Kaneko, Michihiko Nakagaki, Zenji Horita, Grain refinement of commercial Al-Mg alloy using severe torsion straining process, 3rd International Conference on Nanomaterials by Severe Plastics Deformation, NanoSPD3, Severe plastic deformation (SPD) makes it possible to refine grain size in many metallic materials. Recently, we have developed a new SPD process designated the severe torsion straining process (STSP). This process requires no die but one side of a rod is rotated with respect to the other while producing a local heated zone in the rod and cooling both sides of the heated zone. Torsion strain is then introduced in the local heated zone. The STSP can be a continuous process because the rod is moved in the longitudinal direction while introducing torsion strain through the rotation. For grain refinement using the STSP, various factors may affect, which are the rotation speed, moving speed, straining temperature, cooling rate and diameter of the rod. In this study, the STSP is applied to grain refinement of an A5056 Al-Mg commercial alloy and the factors affecting the grain refinement are optimized. STSP was conducted at a temperature in the range from 573K to 723K. Microstracture was observed by optical microscopy, scanning electron microscopy with an orientation imaging system, and transmission electron microscopy. Microscopy observations revealed that the grain size was reduced to ∼0.9 um, when STSP was conducted at 573K with a rotation speed of 10 rpm and moving speed of 50 mm/min. There is a critical ratio of rotation speed to moving speed above which the rod breaks. The grain size tends to be finer as the straining temperature is lower, the cooling rate is faster and the ratio of rotation speed to moving speed is closer to the critical value..
70. Y. Hayashi, T. Tokunaga, Kenji Kaneko, S. J. Henley, V. Stolojan, J. D. Carey, S. R P Silva, Microstructure analyses of metal-filled carbon nanotubes synthesized by microwave plasma-enhanced chemical vapour deposition, 2006 IEEE Conference on Emerging Technologies - Nanoelectronics, Pd/Co-based metal-filled carbon nanotubes (MF-CNTs) were synthesized by a microwave plasma-enhanced chemical vapour deposition method using a bias-enhanced growth technique. Pd/Co-based MF-CNTs were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) electron energy loss spectroscopy (EELS), and Raman spectroscopy. MF-CNTs were well-aligned and uniform in size on a Si substrate. Both multiwall nanotube carbon nanotubes (CNTs) and herringbone (or stacked cups structure) structures were observed. High-resolution TEM revealed that MF-CNTs were composed of highly ordered graphite layers, and the elemental maps of EELS indicate that both Co and Pd metals are present inside the nanotubes. TEM results clearly showed that both Pd and Co metals were successfully encapsulated into the CNTs.. We observed a low value for the Raman intensity ratio between D (1355 cm-1) and G (1590 cm-1) bands with no shift of the G-peak position and no broadening of the G-peak, indicative of high quality Pd/Co-based MF-CNTs. Based on TEM characterization, we propose a description for the encapsulating mechanisms..
71. Yuichi Miyahara, Naoki Emi, Koji Neishi, Katsuaki Nakamura, Kenji Kaneko, Michihiko Nakagaki, Zenji Horita, Microstructures and mechanical properties of Mg alloy after severe torsion straining process, 3rd International Conference on Nanomaterials by Severe Plastics Deformation, NanoSPD3, Grain refinement is attempted using severe plastic deformation (SPD) through the severe torsion straining process (STSP) which we have developed recently. The STSP is a continuous process for grain refinement without requirement of any die. In this study, an AZ61 Mg alloy was subjected to STSP at a temperature of 573 K with a rotation speed of 10 rpm and a moving speed of 200 mm/min. With this process, an initial grain size of ∼20 μm was reduced to ∼2∼3 μm. Room temperature compression tests revealed that there were no cracks after 15% of compression for the STSP sample whereas fracture occurred for a conventionally extruded sample. For compression tests at 473 K, no cracks occurred in the STSP samples after 80% compression but compression was feasible without cracking only up to 20% for an extruded sample. It is shown that the STSP can be useful for grain refinement and ductility improvement of the AZ61 Mg alloy..
72. Ayumu Umemoto, Koichi Hayashi, Kunihiko Nakashima, Noritaka Saito, Kenji Kaneko, Keisaku Ogi, Mo-SiO2 functionally graded materials for high intensity discharge lamp, 6th Pacific Rim Conference on Ceramic and Glass Technology, PacRim6, The conventional high intensity discharge lamps are made of Mo foil-sealing method, in which the Mo-metal of 30 μm thick is sandwiched by the fused silica envelope. The conventional high intensity discharge lamps therefore requires cooling system to reduce the thermal stress between Mo and fused silica during the switching operation and a lung sealing zone is usually required to complete hermeticity, especially in high power devices, so that the production of compact high intensity discharge lamps has been a Herculean task, Here, we show the invention of the new type of hermetically-sealed high intensity discharge lamps, made of Mo-SiO2 functionally graded material (FGM) as an electrode and a sealing component. In the case of high intensity discharge lamps with Mo-SiO2 FGM (FGM-Lanip), the thermal expansion coefficient between Mo and SiO2 is functionally graded so that it tolerates a large number of heating cycles, with no cooling system are required, Furthermore lamps survive without breakage of lamp takes place, The W electrode is totally separated from the lamp envelope by the FGM, so that no leakage of the luminous elements or gases takes place, when a large gas pressure exists inside a lamp..
73. Takahiro Kaseyamaj, Yohei Kubo, Kenji Kaneko, Masayuki Takeuchi, Seiji Shinkai, Nanoscale alignment of conjugated polymers by supramolecular approach(2), 55th Society of Polymer Science Japan Symposium on Macromolecules, We designed and synthesized a compound 1 that can align conjugated polymers. This compound has palladium complexes as molecular recognition units and can align polyanilines. The morphologies of the supramolecular assemblies consisting of this compound and polyaniline were monitored by UV-vis spectroscopy and TEM..
74. Shinji Takebsyashi, Yohei Kubo, Kenji Kaneko, Masayuki Takeuchi, Seiji Shinkai, Nanoscale alignment of conjugated polymers by a supramolecular approach, 55th Society of Polymer Science Japan Symposium on Macromolecules, Exploring new methods for alignment of conjugated polymers is of importance for the production of materials having optimized properties. In these days, several methods for alignment of conjugated polymers have been reported by many research groups. We have recently proposed a new concept for alignment of conjugated polymers where the porphyrinatozinc tetramer was designed and utilized as an Aligner; the molecule binds amino functionalized cojugated polymers (CP1) to align them into the two-dimensional super structures. We here report an attempt on three-dimensional alignment of conjugated polymers by a poly-Aligner..
75. L. Miao, T. Jiang, S. Tanemura, M. Tanemura, M. Mori, S. Toh, Kenji Kaneko, Photochromic Ag-TiO2 thin films fabricated by dual-target helicon magnetron sputtering, AICAM 2005 - Asian International Conference on Advanced Materials, Photochromic material Ag-TiO2 thin films are fabricated on quartz substrate by dual -target helicon magnetron sputtering. The phototchromic behavior is investigated for the sample loaded with 90% Ag. Spheres, ellipsoids and polyhedra shape of Ag particles with wide range size (5∼100 nm) are dispersed in the TiO2 amorphous matrix observed by transmission electron microscopy. The spectral hole burned by the irradiation of laser at the wavelength 532 nm can be explained by a particle-plasmon-assisted electron transfer from Ag nanoparticles to TiO2 and subsequent trapping by adsorbed molecular oxygen. Moreover, the mechanism of the slow recovery after photochromism is suggested as a slow thermal release of electrons from oxygen trapping centers and subsequent capture into the Ag nanoparticles..
76. Masayuki Takeuchi, Chiaki Fujikoshi, Yohei Kubo, Kenji Kaneko, Seiji Shinkai, Sequential organization by a supramolecular twining approach toward the alignment of conjugated polymers, 55th SPSJ Annual Meeting, Here we report that porphyrin polymers (Twining polymer; Twimer) possessing conjugated polymer binding sites would twine around, and align them in a noncovalent fashion (Fig.1). The morphologies of the resulting supramolecular assemblies between twimers and conjugated polymers were monitored by UV-Vis, fluorescence spectroscopies, CLSM, PM, and HRTEM. Very interestingly, they afforded novel well-regulated structures..
77. Atsushi Ikeda, Sayuri Ito, Jun Ichi Kikuchi, Kenji Kaneko, Munenori Numata, Kazuo Sakurai, Seiji Shinkai, Solubilization of C 60 by using biopolymers, 55th SPSJ Annual Meeting, The ready availability of [60]fullerene (C 60) has increasingly invited exploration of their outstanding new physical and chemical properties. Water-solubilization of C 60 holds potential in the application for various medicinal uses. The use of biomolecules as solubilizing agents of C 60 is preferable in order to be applied for medicinal fields because of little or less toxicity. Taking into account these aims, we have now chosen various polysaccharides as solubilizing agents such as amylose and schizophyllan (SPG). We have discovered that amylose and SPG can solved C 60 in water and form the one dimensional ordered C 60 in the hydrophobic cavities..
78. Masayuki Takeuchi, Osamu Hirata, Tomohiro Ikeda, Masayuki Shibata, Kenji Kaneko, Seiji Shinkai, Supramolecular systems utilizing rotational units, 55th Society of Polymer Science Japan Symposium on Macromolecules, We designed portphyrin 1 bearing rotational units at meso-position and porphyrin polymer Pn which has double decker Ce(IV) bisporphyrinate as rotational units and Zn(II) porphyrin as recognition sites alternately. We expected that compound 1 could form one-dimensional supramolecular polymer with Pd complexes, whereas polymer Pn would be expected to fold at the vertex double-decker porphyrin complex in the presence of guests..
79. Koji Inoke, Kenji Kaneko, Zenji Horita, Three-dimensional imaging of shear band produced by ECAP process in Al-Ag alloy, 3rd International Conference on Nanomaterials by Severe Plastics Deformation, NanoSPD3, A significant change in microstracture occurs during the application of severe plastic deformation (SPD) such as by equal-channel angular pressing (ECAP). In this study, intense plastic strain was imposed on an Al-10.8wt%Ag alloy by the ECAP process. The amount of strain was controlled by the numbers of passes. After 1 pass of ECAP, shear bands became visible within the matrix. With increasing numbers of ECAP passes, the fraction of shear bands was increased. In this study, the change in microstructures was examined by three-dimensional electron tomography (3D-ET) in transmission electron microscopy (TEM) or scanning transmission electron microscopy (STEM). With this 3D-ET method, it was possible to conduct a precise analysis of the sizes, widths and distributions of the shear bands produced by the ECAP process. It is demonstrated that the 3D-ET method is promising to understand mechanisms of microstractural refinement using the ECAP process..
80. Chiaki Fujikoshi, Yohei Kubo, Masayuki Takeuchi, Seiji Shinkai, Kenji Kaneko, Alignment of conjugated polymers by supramolecular porphyrin polymer (3), 54th SPSJ Symposium on Macromolecules, Here we report that porphyrin polymer (Twining polymer; Twimer) possessing conjugated polymer binding sites would twine around, and align them in a noncovalent fashion (Fig.1). The morphologies of the resulting supramolecular assemblies between twimers and conjugated polymers were monitored by UV-Visible, fluorescence spectroscopies, CLSM, PM, and HR TEM. Very interestingly, they afforded novel well-regulated network structure..
81. Yohei Kubo, Rie Wakabayashi, Chiaki Fujikoshi, Kenji Kaneko, Masayuki Takeuchi, Seiji Shinkai, Alignment of conjugated polymers by supramolecular porphyrin oligomer (1), 54th SPSJ Symposium on Macromolecules, We here report a preliminary step toward alignment and organization of conjugated polymers by an Aligner molecule with an allosteric function. Aligner molecules 1 and 2, which show positive homotropic allosterism, can bind a guest poly(phenylene-ethynylene) bearing bis(methylaminomethyl)benzene moieties (P1) in their porphinatozinc clefts to organize assemblies of P1. The binding studies were conducted by UV-Vis, fluorescent spectroscopy, AFM and TEM..
82. Rie Wakabayashi, Yohei Kubo, Masayuki Takeuchi, Seiji Shinkai, Kenji Kaneko, Alignment of conjugated polymers by supramolecular porphyrin oligomer (2), 54th SPSJ Symposium on Macromolecules, We proposed a novel approach for aligning and organizing of conjugated polymers by Aligners, which possess several binding sites for conjugated polymers. In this system, however, the supramolecular assemblies between Aligners and polymers are under thermodynamic control and could be destroyed by dilution or other external factors. Aligner 3, which possesses olefins as reaction sites, can bind a guest poly(phenylene-ethynylene) (poly-PPE) and organize assemblies of poly-PPEs. These assemblies were able to be immobilized by metathesis reaction..
83. Masayuki Takeuchi, Satoshi Tanaka, Kenji Kaneko, Seiji Shinkai, Porphyrin-based supramoleculr assmenbies, 54th SPSJ Symposium on Macromolecules, Here we report that the morphology of one-dimensional aggregates composed of porphyrins can be controlled by the peripheral hydrogen-bond donating/accepting groups and van der Waals interactions among alkyl chains introduced in the orthogonal axis toward the porphyrin-porphyrin π π stacking axis. The supramolecular assemblies of porphyrin derivatives were monitored by UV-Visible, XRD, SEM, TEM, and HR-TEM. Very interestingly, they afforded a variety of supramolecular morphologies such as helical ribbon, sphere, doughnut, and cylinder depending on the environmental conditions..