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1.
Sawao Honda Kento Nakashima Taketo Yoshida Yusuke Daiko Shinobu Hashimoto Yuji Iwamoto 《Journal of the American Ceramic Society》2021,104(2):1178-1187
To quantitatively investigate the initial crystallization of zeolite beta synthesized by direct heating, the extent of the reaction was precisely evaluated by X-ray diffraction measurements and Rietveld structural refinement, and a kinetic analysis of crystallization was performed using the Avrami-Erofe'ev equation. The activation energy for crystallization was lower than that for hydrothermal synthesis. Reaction and synthesis time curves revealed that the initial zeolite beta crystallization consisted of three stages. The first was an induction period with nucleation by the generation of building units and the formation of an initial coordinated structure. The second stage was crystal growth by a diffusion-controlled reaction, and the third stage involved slowing down of crystallization by the limitation of dehydrocondensation. These stages could be analyzed by calculation of the rate constant and Avrami exponent for each stage. 相似文献
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Lawanwong Komgrit Hamasaki Hiroshi Hino Ryutaro Yoshida Fusahito 《The International Journal of Advanced Manufacturing Technology》2020,106(5):1855-1867
The International Journal of Advanced Manufacturing Technology - This paper presents a novel technology called ‘double-action bending (DAB)’ to eliminate springback in hat-shape forming... 相似文献
4.
Marija Prekajski Đorđević Jelena Maletaškić Nadežda Stanković Biljana Babić Katsumi Yoshida Toyohiko Yano Branko Matović 《Ceramics International》2018,44(2):1771-1777
Hydroxyapatite was used as the inert matrix for in-situ immobilization of strontium (Sr) radioactive isotopes at room temperature. A nano-emulsification method was applied to synthesize Sr-substituted calcium hydroxyapatite (Ca1?xSrx)10(PO4)6(OH)2. The concentration of incorporated Sr was in the range of 0 ≤ x ≤ 1. Immobilization of Sr was evaluated using a stable isotope instead of radioactive isotope. The effect of strontium concentration on the crystal structure was studied and the results have showed that in the whole concentration range, Sr forms solid solutions with the host hydroxyapatite crystal structure. Powders comprised of nanometre sized particles were obtained and their properties, such as crystallite and particle size, changes in lattice parameters as function of dopant content and thermal stability, were further examined. It was found that the crystal structure of obtained powders is thermally stable at high temperatures. No secondary phases were formed in as-prepared powders or during calcination. The results in this study showed that nano-emulsion strategy provides a simple pathway for synthesis of a single-phase Sr-substituted hydroxyapatite, which can be used for immobilization of Sr radioactive isotopes. 相似文献
5.
Koji Morita Byung-Nam Kim Hidehiro Yoshida Keijiro Hiraga Yoshio Sakka 《Journal of the European Ceramic Society》2018,38(6):2588-2595
Carbon contamination from the carbon paper/dies during spark-plasma-sintering (SPS) processing was examined in the MgAl2O4 spinel. The carbon contamination sensitively changes with the heating rate during the SPS processing. At the high heating rate of 100 °C/min, the carbon contamination having organized structures occurred over almost the entire area from the surface to deep inside the SPSed spinel disk. In contrast, at the slow heating rate of 10 °C/min, the carbon contamination having disordered structures occurred only around the surface area. The carbon phases transform into high pressure CO/CO2 gases by post-annealing in air and lead to pore formation along the grain junctions. The pore formation significantly occurs at the high heating rate due to the large amount of the contaminant carbon phases. This suggests that if once the carbon contamination was formed in the materials, it is very difficult to remove the carbon phases from the materials. 相似文献
6.
Development of Novel Inhibitors for Histone Methyltransferase SET7/9 based on Cyproheptadine 下载免费PDF全文
Dr. Tomoya Hirano Dr. Takashi Fujiwara Dr. Hideaki Niwa Michitake Hirano Kasumi Ohira Yusuke Okazaki Shin Sato Dr. Takashi Umehara Dr. Yuki Maemoto Prof. Akihiro Ito Prof. Minoru Yoshida Prof. Hiroyuki Kagechika 《ChemMedChem》2018,13(15):1530-1540
The histone methyltransferase SET7/9 methylates not only histone but also non‐histone proteins as substrates, and therefore, SET7/9 inhibitors are considered candidates for the treatment of diseases. Previously, our group identified cyproheptadine, used clinically as a serotonin receptor antagonist and histamine receptor (H1) antagonist, as a novel scaffold of the SET7/9 inhibitor. In this work, we focused on dibenzosuberene as a substructure of cyproheptadine and synthesized derivatives with various functional groups. Among them, the compound bearing a 2‐hydroxy group showed the most potent activity. On the other hand, a 3‐hydroxy group or another hydrophilic functional group such as acetamide decreased the activity. Structural analysis clarified a rationale for the improved potency only by tightly restricted location and type of the hydrophilic group. In addition, a SET7/9 loop, which was only partially visible in the complex with cyproheptadine, became more clearly visible in the complex with 2‐hydroxycyproheptadine. These results are expected to be helpful for further structure‐based development of SET7/9 inhibitors. 相似文献
7.
Shogo Mamada Naoyuki Yaguchi Masanori Hansaka Masafumi Yamato Hirohisa Yoshida 《应用聚合物科学杂志》2015,132(15)
This study was addressed to the influence of an electric field strength applied at fabrication process and matrix properties, such as the dielectric constant and the Young's modulus, on “pseudo‐1‐3 piezoelectric ceramic/polymer composite” in order to further enhance the piezoelectricity of that. The pseudo‐1‐3 piezoelectric ceramic/polymer composite consists of linearly ordered piezoelectric ceramic particles in polymer material. Silicone gel, silicone rubber, urethane rubber, and poly‐methyl‐methacrylate, which exhibit different dielectric constants and Young's modulus, were used as matrices to evaluate the matrix influence. The piezoelectricity of the pseudo‐1‐3 piezoelectric ceramic/polymer composite was evaluated using the piezoelectric strain constant d33. The d33 is one of the indices of the piezoelectric properties for piezoelectric materials. As a result, it was confirmed that d33 of the pseudo‐1‐3 piezoelectric ceramic/polymer composite increased with the increase of the electric filed strength applied at fabrication process, though, it reached a constant value at a certain strength value. Further it was confirmed that dielectric constant of the matrix had a small influence on d33 of the pseudo‐1‐3 piezoelectric ceramic/polymer composite, however, in case of matrix of lower Young's modulus, d33 was increase. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41817. 相似文献
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Trans‐fatty acid promotes thrombus formation in mice by aggravating antithrombogenic endothelial functions via Toll‐like receptors 下载免费PDF全文
Kensuke Kondo Tatsuro Ishida Tomoyuki Yasuda Hideto Nakajima Kenta Mori Nobuaki Tanaka Takeshige Mori Tomoko Monguchi Masakazu Shinohara Yasuhiro Irino Ryuji Toh Yoshiyuki Rikitake Kazunobu Kiyomizu Yoshiaki Tomiyama Junichiro Yamamoto Ken‐ichi Hirata 《Molecular nutrition & food research》2015,59(4):729-740
10.
Ken Kanazawa Shoji Yoshida Hidemi Shigekawa Shinji Kuroda 《Science and Technology of Advanced Materials》2015,16(1)
The reconstructed surface structure of the II–VI semiconductor ZnTe (110), which is a promising material in the research field of semiconductor spintronics, was studied by scanning tunneling microscopy/spectroscopy (STM/STS). First, the surface states formed by reconstruction by the charge transfer of dangling bond electrons from cationic Zn to anionic Te atoms, which are similar to those of IV and III–V semiconductors, were confirmed in real space. Secondly, oscillation in tunneling current between binary states, which is considered to reflect a conformational change in the topmost Zn–Te structure between the reconstructed and bulk-like ideal structures, was directly observed by STM. Third, using the technique of charge injection, a surface atomic structure was successfully fabricated, suggesting the possibility of atomic-scale manipulation of this widely applicable surface of ZnTe. 相似文献