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131.
Satoshi Abo Shunya KumanoTakayuki Azuma Ryota SugimotoKohei Koresawa Katsuhisa MurakamiFujio Wakaya Mikio Takai 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(20):2233-2236
Single, double and triple-layer test structures were measured by time of flight (TOF) Rutherford backscattering spectrometry (RBS) for checking the sensitivity and resolution. A single-layer nanostructure with Au stripes on a Si substrate was resolved by TOF-RBS measurement within a short time of 256 s. The spatial resolution, measured by the edge of the Au stripes, was 42 nm. Another single-layer nanostructure with Pt stripes fabricated by electron beam (EB) induced deposition on a Si substrate was resolved by TOF-RBS measurement even at a thickness of Pt stripes less than one mono-layer. Ga embedded layers implanted by a focused ion beam under the Pt stripes fabricated by EB induced deposition on a Si substrate could be detected for a double-layer nanostructure. Furthermore, a triple-layer nanostructure with two Pt stripe layers isolated by a SiO2 layer fabricated by EB induced deposition on a Si substrate could be resolved and cross-sections shown. 相似文献
132.
Katsuyoshi Hoshino Yosuke Oikawa Ichiro Sakabe Toshiki Komatsu 《Electrochimica acta》2009,55(1):165-170
The electrochromic properties of 1,1′-dibenzyl-4,4′-bipyridinium and 1,1′-diheptyl-4,4′-bipyridinium were investigated in the presence of MBr (M = Li+, Na+, and K+). The cyclic voltammograms of these viologens showed a white-coloured state in addition to the usual violet one-electron reduction state and the colourless divalent state. Chemical analyses (FT-IR and XPS spectra) of the white film and some control experiments with different supporting electrolytes, MX (X = Cl− and I−), revealed that the viologens formed water-insoluble ion pairs with tribromide generated by the electrooxidation of monobromide to produce a white film. The film was reversibly decolourized electrochemically to the initial transparent state, providing the polyelectrochromism using the simple viologen/MBr systems. The colouration efficiencies for the violet and the white-coloured states were 170 cm2/C and 104 cm2/C, respectively. 相似文献
133.
134.
Kenichi Hashizume Ryosuke Onji Shinpei Niiki Hideaki Tsukuda Ryota Yoshida 《亚洲传热研究》2009,38(3):156-167
Heat transfer coefficients were measured on tube bundles of fundamental layouts including in‐line layouts embedded horizontally in a liquid‐fluidized bed. Tested tube layouts were single tubes, transverse single tube rows, longitudinal single tube rows, and in‐line arranged tube bundles. A total of 7 kinds of particles were used. Comparisons of the experimental data showed a good agreement with the heat transfer correlation developed for staggered layouts, when the average liquid velocity through each tube bundle was used as the reference velocity for the particle Reynolds number. Distribution of the local heat transfer coefficient was also investigated around tubes. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20245 相似文献
135.
Koji Tanaka Daiji Nishino Kousei Hayashi Shuki Ikeuchi Ryota Kondo Hiroyuki T. Takeshita 《International Journal of Hydrogen Energy》2017,42(35):22502-22510
The formation mechanism of microstructures in Mg/Cu super-laminates composites (SLCs) fabricated by accumulative roll-bonding (ARB) during initial activation was investigated. It is revealed that Mg2Cu can grow with sufficient growth rate at low temperatures (<453 K) in Mg/Cu SLCs. The growth of Mg2Cu layers for short growth length is diffusion-controlled. The activation energies for layer growth process of Mg2Cu layers in Mg/Cu SLCs are 107 ± 8 kJmol?1 with acid cleaning prior to ARB and 103 ± 12 kJmol?1 without acid cleaning prior to ARB, respectively, which are about 2/3 of those in MgCu diffusion couples. It is considered that the high density of lattice defects in Mg/Cu SLCs fabricated by ARB contributes the much lower activation energies for layer growth process of Mg2Cu layers in Mg/Cu SLCs than in MgCu diffusion couples. 相似文献
136.
Ryota Negishi Hiroki HiranoYasuhide Ohno Kenzo MaehashiKazuhiko Matsumoto Yoshihiro Kobayashi 《Thin solid films》2011,519(19):6447-6452
We demonstrate a synthesis of graphene layers on graphene templates prepared by the mechanical exfoliation of graphite crystals using a developed chemical vapor deposition (CVD) apparatus that has a furnace with three temperature zones and can regulate the temperatures separately in each zone. This results in individual control over the decomposition reaction of the carbon feedstock and the growth of graphene layers by activated carbon species. CVD growth using multi-temperature zones provides wider temperature windows appropriate to grow graphene layers. We observed that graphene layers proceed by a layer-by-layer growth mode using an optical microscopy, an atomic force microscopy, and Raman spectroscopy. This result suggests that a graphene growth technique using the CVD apparatus is a potential approach for making graphene sheets with precise control of the layer numbers. 相似文献
137.
Yuichi Watanabe Ken Muramatsu Tetsukuni Oikawa 《Nuclear Engineering and Design》2005,235(23):2495-2512
This paper presents an evaluation of seismic capacity of a group of vertical U-tube type heat exchangers (HXs) with support frames to contribute to refinement of seismic capacity data for seismic Probabilistic Safety Assessment (PSA) in Japan. According to usual practice of seismic PSAs, capacity of component is represented as a log-normally distributed random variable defined by a median and logarithmic standard deviations (LSDs), which represent inherent randomness about the median, βr, and uncertainty in the median due to lack of knowledge, βu. Using design specifications of four HXs for residual heat removal systems of 1100 MWe BWRs, the authors evaluated a generic capacity of HXs with a LSD for uncertainty due to lack of knowledge to take into account design variability. The median capacity was evaluated by the use of a time history response analysis with a detailed model for a selected representative HX, which was extended from a model used in seismic design. The LSD for uncertainty due to lack of knowledge was evaluated with consideration of the variabilities in three influential design parameters, i.e., diameter of anchor bolt, weight of HX and position of center of gravity of HX with the detailed model and a simplified static model. The LSD for uncertainty due to randomness was determined from the variability in material property. The dominant failure mode of HXs was identified as the failure of anchor bolts of lugs mainly due to shearing stress. The capacity expressed in terms of zero period acceleration on the foundation of HX was evaluated to be 4180 Gal (4.3 g) for median, LSD for uncertainty due to randomness was 0.11 and LSD due to lack of knowledge was 0.21–0.53 depending on combination of the variabilities in design parameters to be considered. 相似文献
138.
The "imaging plate" is a highly sensitive image recording plate for X-ray radiography, which is coated with photo-stimulable phosphor. The imaging plate is exposed to electrons in a transmission electron microscope. Its fundamental properties (sensitivity, dynamic range and sharpness) have been estimated in detail. Also, the image quality of the imaging plate for some specimens in a transmission electron microscope has been estimated. As a result, it has been ascertained that the imaging plate has superior properties and high practicability as an image recording material in a transmission electron microscope. 相似文献
139.
140.
Keiji Morishita Kazuhisa Fujita Ryota Kakei Hiroki Furuki Tomoyuki Okada 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(5):293-297
We applied carbon nanotube (CNT) sheets, which are high-purity and suitable for mass production, to field-emission lamps (FELs) with vacuum-sealed diode structures. Three such FELs were designed and fabricated to correspond to the field-emission characteristics of individual CNT sheets. We suppressed the variation in the anode–cathode voltage to within the range of 5.4–6.0 kV, which contributes to the light output of the FELs. The stabilities of the FELs ranged from ?0.65% to 0.26% in the short term; therefore, we confirmed that the high-purity CNT sheets were stable during operation. All FELs could be operated for 500 h without significant degradation, even when the FEL was operated in a passive vacuum instead of a dynamic vacuum. 相似文献