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71.
Takayuki Kumada Shoji Mori Toshimitsu Nagasaka Jun Kumagai Tetsuo Miyazaki 《Journal of Low Temperature Physics》2001,122(3-4):265-277
The tunneling abstraction reaction: H+H2H2+H in -irradiated solid hydrogen has been studied using electron spin resonance (ESR) and electron-nuclear double resonance (ENDOR) spectroscopy and gas-chromatography. The rate constant for the tunneling reaction in solid hydrogen was found to decrease with the increase in the concentration of ortho-H2 molecules in solid hydrogen. We concluded that the decrease in the rate constant is due to the energy level mismatching between reactant species of H+H2 trapped and product species of H2+H trapped in the reverse induced by inhomogeneous intermolecular interactions between ortho-H2 molecules in solid hydrogen. This result indicates that resonance effects play an important role in tunneling reactions in solids. 相似文献
72.
Inside Cover: Onocerin Biosynthesis Requires Two Highly Dedicated Triterpene Cyclases in a Fern Lycopodium clavatum (ChemBioChem 4/2016) 下载免费PDF全文
73.
Ryo Miura Tetsuo Fujishima Hiromichi Uchimura Kensuke Toda Makoto Kobayashi Naoko Ashikawa Akio Sagara Naoaki Yoshida Yuji Hatano Yasuhisa Oya Kenji Okuno 《Fusion Engineering and Design》2013,88(9-10):1827-1830
The D2+ fluence dependence on deuterium (D) retention was studied to clarify the D retention mechanism in tungsten. The additional D desorption stage was observed around 660 K in the TDS spectrum for a sample implanted with D2+ up to the fluence of 1023 D+ m?2, which desorption stage was not observed the D2+ implanted sample with the fluence less than 1022 D+ m?2. The TEM observation showed that the highly dense voids were formed in tungsten by D2+ implantation with the fluence of 1023 D+ m?2, considering that the D would be trapped by voids. To understand the D trapping by voids in C+ implanted tungsten, C+–D2+ sequential implantation experiments at various C+ implantation temperatures were performed. It was found that the amount of D desorbed around 560 K was increased by increasing the C+ implantation temperature. The formation of the voids was observed with increasing the C+ implantation temperature by TEM, indicating that the increase of D desorption around 560 K was caused by the formation of voids. However, the desorption temperature of D trapped by voids in C+ implanted sample was lower than that in D2+ implanted one. TEM observation and XPS measurement indicated that this difference was caused by the increase of void size and/or the presence of implanted carbon. 相似文献
74.
Hisayasu Mitsui Ryoji Kumazawa Rie Aizawa Tatsuki Okamoto Tetsuo Ito Masaki Kanegami 《Electrical Engineering in Japan》1999,129(4):24-31
Experiments and investigations were carried out on the voltage life of a bar-coil model with a nickel-plated copper conductor covered with mica-alumina composite insulation at a temperature range of 550–850 °C. Diffusion of copper into the insulation layer was observed on the specimens aged for a long period. Insulation with mica paper gave faster diffusion speed and shorter voltage life than insulation with mica flake. The diffusion speed became higher with an increase in temperature. The ac current gradually increased with aging time and increased rapidly just before breakdown. There was the relationship I = aEn (a, n: constants) between ac current I and applied stress E, and n was approximately equal to 1 in the region where thermal unbalance did not occur. Arrhenius's law held in the relationship between ac current and aging time. Therefore, the breakdown mechanism might be that the effective insulation thickness decreased due to copper diffusion into the insulation layer and the ac current increased gradually until thermal breakdown in the last stage. If copper diffuses into the insulation layer, even with no voltage application, the aging time required to decrease the breakdown voltage to a certain level (the voltage life) obeys Arrhenius's law. If the voltage life is dominated by diffusion into the insulation layer, the activation energy for voltage life in the aging test becomes twice that for diffusion, both with and without voltage application. © 1999 Scripta Technica, Electr Eng Jpn, 129(4): 24–31, 1999 相似文献
75.
Mehta DS Hinosugi H Saito S Takeda M Kurokawa T Takahashi H Ando M Shishido M Yoshizawa T 《Applied optics》2003,42(4):682-690
The maximum measurable range of a spectral interference microscope depends on the coherence length of the light transmitted by its tunable spectral filter. To achieve a large range in step-height measurement we have developed a new tunable spectral filter that uses tandem liquid-crystal Fabry-Perot interferometers (LC-FPIs), which can simultaneously attain both a high spectral resolution and a large tuning range. Fringe visibility measurements were carried out, and it was found that the coherence length of the light transmitted through tandem LC-FPIs is two times larger than that transmitted through a single LC-FPI. Using this novel tunable spectral filter, we developed a new spectral interference microscope for the measurement of three-dimensional shapes of discontinuous objects. Experimental results of step-height measurements both with a single LC-FPI and with tandem LC-FPIs are presented for a combination of standard steel gauge block sets with 1-, 99-, and 100-microm steps. A large range (1-100 microm) of measurement with submicrometer resolution was achieved with tandem LC-FPIs that was not possible with our previous system in which a single LC-FPI was used. 相似文献
76.
We present a computing environment for origami on the web. The environment consists of the computational origami engine Eos for origami construction, visualization, and geometrical reasoning, WebEos for providing web interface to the functionalities of Eos, and web service system Scorum for symbolic computing web services. WebEos is developed using Web2.0 technologies, and provides a graphical interactive web interface for origami construction and proving.
In Scorum, we are preparing web services for a wide range of symbolic computing systems, and are using these services in our origami
environment. We explain the functionalities of this environment, and discuss its architectural and technological features. 相似文献
77.
Yasuyuki Kaneno Tetsuo Yamaguchi Takayuki Takasugi 《Journal of Materials Science》2006,41(20):6871-6880
The texture evolution during the hot-rolling and the recrystallization of B2-type Fe–48Al, Ni–50Al and Co–50Ti (expressed
by at.%) intermetallic compounds were investigated. By hot-rolling at 973 K, Fe–48Al showed a microstructure with coarse grains
elongated along rolling direction, while Ni–50Al and Co–50Ti showed a deformed microstructure featured by the heavily distorted
(elongated) grains and/or the deformation bands. The hot-rolling texture of Fe–48Al was composed of {111}<uvw>, while those
of Ni–50Al and Co–50Ti were composed of {111}<110> and {111}<112>, respectively. After annealing, the recrystallized grains
were preferentially nucleated at the grain boundaries for Fe–48Al, and in the heavily distorted regions or the deformation
bands for Ni–50Al and Co–50Ti. The orientations of the recrystallized grains were similar with those of the deformed matrix,
especially for Ni–50Al and Co–50Ti. The recrystallization textures were generally more dispersive than the hot-rolling texture.
Based on these results, the texture evolution during the hot rolling and the recrystallization of the B2-type intermetallic
compounds were discussed. 相似文献
78.
Natsuhiko Kuratomi Shinichi Takano Mitsuharu Fukasawa Shinya Maekawa Makoto Kadokura Hiroko Shindo Ei Takahashi Sumio Hirose Yoshimitsu Fukasawa Satoshi Kawakami Hiroshi Hayakawa Hitomi Takada Natsuko Nakakuki Ryoh Kato Tatsuya Yamaguchi Yasuhiro Nakayama Hiromichi Kawaida Hiroshi Kono Taisuke Inoue Tetsuo Kondo Daisuke Ichikawa Nobuyuki Enomoto 《International journal of molecular sciences》2021,22(6)
New biomarkers are needed to further stratify the risk of malignancy in intraductal papillary mucinous neoplasm (IPMN). Although microRNAs (miRNAs) are expected to be stable biomarkers, they can vary owing to a lack of definite internal controls. To identify universal biomarkers for invasive IPMN, we performed miRNA sequencing using tumor-normal paired samples. A total of 19 resected tissues and 13 pancreatic juice samples from 32 IPMN patients were analyzed for miRNA expression by next-generation sequencing with a two-step normalization of miRNA sequence data. The miRNAs involved in IPMN associated with invasive carcinoma were identified from this tissue analysis and further verified with the pancreatic juice samples. From the tumor-normal paired tissue analysis of the expression levels of 2792 miRNAs, 20 upregulated and 17 downregulated miRNAs were identified. In IPMN associated with invasive carcinoma (INV), miR-10a-5p and miR-221-3p were upregulated and miR-148a-3p was downregulated when compared with noninvasive IPMN. When these findings were further validated with pancreatic juice samples, miR-10a-5p was found to be elevated in INV (p = 0.002). Therefore, three differentially expressed miRNAs were identified in tissues with INV, and the expression of miR-10a-5p was also elevated in pancreatic juice samples with INV. MiR-10a-5p is a promising additional biomarker for invasive IPMN. 相似文献
79.
Transparent La0.33NbO3 flakes were fabricated by a rapid quenching technique. The quenched La0.33NbO3 phase takes a simple cubic perovskite structure and cation vacancies are randomly distributed on the A sites. The cubic La0.33NbO3 phase is a new modification which is different from the well-known orthorhombic phase with ordered A-site vacancies. Transparent flakes were found to show the predominant orientation of (110) and (220) planes. 相似文献
80.
Fengqiu Tang Tetsuo Uchikoshi Yoshio Sakka 《Journal of the American Ceramic Society》2002,85(9):2161-2165
The rheological behavior and electrophoretic deposition (EPD) of ZnO nanopowder (nano-ZnO) in aqueous media have been described. A cationic polyelectrolyte (polyethylenimine, PEI) was used to disperse and modify the surfaces of the ZnO nanoparticles. The rheological properties of the ZnO aqueous suspension were investigated by measuring the viscosity versus the pH and amount of dispersant. The EPD processing was conducted via cathodic electrodeposition, using stable suspensions with low viscosity, and the depositional behavior was investigated. Bubble-free nano-ZnO deposits with uniform microstructures were successfully obtained, which was an indication of good sintering behavior. 相似文献