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101.
Si photonics becomes one of the research focuses in the field of photonics.Si-based light-emitting devices are one of the most important devices in this field.In this paper,we review the Si-based light... 相似文献
102.
The present study demonstrates the significant influence of ageing in the formation electrolyte on the morphology and composition of anodic films grown on zirconium in 0.35 M ammonium fluoride in glycerol. Ageing after anodizing, by immersion in the electrolyte for 1 h, is shown to promote a transition from a porous to a nanotubular morphology, due to the dissolution of the fluoride-rich intratubular material in which the nanotubes are embedded. The morphological change is accompanied by a significant loss of zirconium and fluorine from the film. In contrast, ageing in deionized water has little influence on the films. 相似文献
103.
Mitsuhiro Kubota Takuya Hanada Satoshi Yabe Hitoki Matsuda 《Applied Thermal Engineering》2013,50(2):1576-1581
Microwave heating, because of its advantages of direct and rapid heating of materials, has the potential to be employed as a novel regeneration method of desiccant rotors in humidity conditioners. We proposed a combined regeneration process, which combines microwave heating and conventional hot-air heating. The system is expected to achieve high heating rate during an initial regeneration period by assisting water desorption using the additional energy of the microwave. In this study, the regeneration characteristics of a desiccant rotor were experimentally investigated under conditions of microwave heating, hot-air heating, and combined heating at various microwave powers and hot-air temperatures. The effectiveness of the combined regeneration was evaluated in terms of the regeneration ratio, the initial regeneration rate, the temperature distribution in the rotor, and finally in terms of the energy consumption. It was demonstrated that combined heating was effective at leveling non-uniform temperature distribution in the rotor. Combined heating achieved higher ratios and initial rates in regeneration compared to just microwave and hot-air heating. This result was obviously attributed to the additional input of microwave energy, resulting that average rotor temperature increased by microwave absorption of rotor. Moreover, it was also effective for enhancement of regeneration to level the temperature distribution in the rotor by combination of two heating methods with different heating mechanisms. Both the initial regeneration rate and the equilibrium regeneration ratio for combined heating were found to increase as the microwave power increased. A linear relationship was observed with respect to microwave power. From the viewpoint of energy consumption, it may be possible to apply combined and microwave heating to humidity control systems that switch between adsorption and regeneration in short cycle times, if the conversion and absorption efficiencies of the microwave are significantly improved. 相似文献
104.
Noritsugu Hashimoto Seiji Niijima Jun-ichi Inagaki 《Journal of the European Ceramic Society》2009,29(14):3039-3043
Solid oxide fuel cells (SOFCs) are very attractive for their high energy conversion efficiency and low emissions. Generally, a supported layer of SOFCs is fabricated by tape casting, using an organic solvent. Recently, a slurry based on water instead of an organic solvent has been sought in order to avoid environmental pollution. In this study, the anode of SOFCs was fabricated by aqueous tape casting, and the electrolyte and the cathode were deposited by screen printing. The I–V characteristics of the cell thus obtained were evaluated. As a result, an 80 mm diameter-sized cell with a power density of 0.33 W/cm2 at 800 °C was successfully fabricated by controlling sintering conditions. 相似文献
105.
Methylcyclohexane dehydrogenation for hydrogen production via a bimodal catalytic membrane reactor
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Lie Meng Xin Yu Takuya Niimi Hiroki Nagasawa Masakoto Kanezashi Tomohisa Yoshioka Toshinori Tsuru 《American Institute of Chemical Engineers》2015,61(5):1628-1638
The dehydrogenation of methylcyclohexane (MCH) to toluene (TOL) for hydrogen production was theoretically and experimentally investigated in a bimodal catalytic membrane reactor (CMR), that combined Pt/Al2O3 catalysts with a hydrogen‐selective organosilica membrane prepared via sol‐gel processing using bis(triethoxysilyl) ethane (BTESE). Effects of operating conditions on the membrane reactor performance were systematically investigated, and the experimental results were in good agreement with those calculated by a simulation model with a fitted catalyst loading. With H2 extraction from the reaction stream to the permeate stream, MCH conversion at 250°C was significantly increased beyond the equilibrium conversion of 0.44–0.86. Because of the high H2 selectivity and permeance of BTESE‐derived membranes, a H2 flow with purity higher than 99.8% was obtained in the permeate stream, and the H2 recovery ratio reached 0.99 in a pressurized reactor. A system that combined the CMR with a fixed‐bed prereactor was proposed for MCH dehydrogenation. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1628–1638, 2015 相似文献
106.
Takuya Orihashi Toshihiro Nakamura Sadao Adachi 《Journal of the American Ceramic Society》2016,99(9):3039-3046
The europium titania materials, pyrochlore Eu2Ti2O7 and orthorhombic Eu2TiO5, were synthesized from a mixture of Eu2O3 and TiO2 using the solid‐state reaction method. The structural and optical properties of these titania materials were investigated using X‐ray diffraction analysis, photoluminescence (PL) analysis, PL excitation (PLE) spectroscopy, and diffuse reflectance spectroscopy. Temperature dependence of the PL intensity was measured between T = 20 and 450 K and analyzed on the basis of various theoretical models. A remarkable increase in the PL intensity with increasing T was observed in these titania materials at higher temperatures, above ~140 K, and well explained by a trap/reservoir model. Interestingly, a dramatic decrease in the electric‐dipole emission component relative to the magnetic‐dipole one was observed in Eu2Ti2O7 above T ~ 140 K. The schematic energy‐level diagram for Eu3+ in the Eu2Ti2O7 host was proposed for the sake of a better understanding of the PL and PLE processes in this type of phosphorescent material. 相似文献
107.
Yoshimitsu Yamada Takashi Tsuchida Nyan Myint Kyaw Tatsuru Aoyama Moe Myint Su Hlaing Ryota Hashimoto 《Soils and Foundations》2019,59(6):2279-2298
Recently, a great deal of foreign investment has been entered into construction of the social infrastructure of Myanmar. Many construction projects are therefore on-going, and these are especially planned in the Yangon area. While these construction booms are increasing, existing studies on the geotechnical problems in the Yangon area such as problematic soils like soft clays are limited at present. Information on soil properties has also not been shared and has been confined to individual projects. In this paper, the boring and laboratory tests carried out in the Yangon area are selected and focused upon among the tests carried out in Myanmar. Laboratory test results for clay deposits in the Yangon area are analyzed and the differences in soil properties between different sedimentary basins and sub-areas divided by the Tertiary sediment ridge that runs from north to south at the center of Yangon are clarified together with a comparison to the clays found in other countries, which have been previously investigated. 相似文献
108.
Isamu Ogura Naomi Hashimoto Mari Kotake Hiromu Sakurai Atsuo Kishimoto Kazumasa Honda 《Aerosol science and technology》2014,48(7):758-767
A simple sampling method to collect aerosol particles for transmission electron microscope (TEM) analysis was developed by R’mili and others in 2013. The method involves passing air through a holey carbon film-coated copper mesh TEM grid (holey carbon grid) and sampling particles by filtration. In this study, we proposed a modified calculation method to represent the collection efficiencies of holey carbon grids, taking into consideration the porosity of the copper mesh. We then evaluated the particle collection efficiencies of holey carbon grids both theoretically and experimentally. We tested the collection efficiency of two types of holey carbon grids, with nominal pore sizes of 1.2 and 0.6 μm, using particles of monodispersed polystyrene latex (PSL) and potassium chloride. The overall collection efficiency of each grid (Egrid) was determined by the downstream/upstream concentration ratio measured by condensation particle counters (CPCs). In addition, for PSL particles, the collection efficiency of the holey carbon film (Efilm) was determined by the ratio of the number of particles on the film (counted on a scanning electron microscope) to the number of inflow particles (counted by a CPC). We compared model calculations against the experimental results obtained in this study and those reported by R’mili and others in 2013. These data showed that the calculated Egrid values were in reasonably good agreement with the experimental Egrid values. However, although the model calculation indicated that Efilm ≈ Egrid, there was an inconsistency between the experimental Efilm and Egrid, which requires further investigation in order to determine its cause.
Copyright 2014 American Association for Aerosol Research 相似文献
109.
Toshihiko Kuwabara Kazuma Hashimoto Eiji Iizuka 《Journal of Materials Processing Technology》2011,211(3):475-481
The deformation behavior of 780 MPa grade dual-phase steel sheet subjected to hole expansion is investigated both experimentally and analytically to clarify the effect of the material model (anisotropic yield function) on the predictive accuracy of finite element analysis of hole expansion. Biaxial tensile tests of the material were conducted; contours of plastic work and the directions of plastic strain rates are precisely measured and are in good agreement with those predicted from the Yld2000-2d yield function with an exponent of 4 (
[Barlat et al., 2003] and [Yoon et al., 2004]). Finite element and experimental analyses on the hole expansion of the material were conducted. The Yld2000-2d yield function with an exponent of 4 provides closer agreement with the experimental results than other yield functions. Consequently, the anisotropic yield functions significantly affect the predictive accuracy of the deformation behavior of the steel sheet subjected to hole expansion, and the biaxial tensile test is effective for identification of the appropriate anisotropic yield function to be used for hole expansion simulation. 相似文献
110.
Shinobu Mukasa Tsunehiro Maehara Shinfuku Nomura Hiromichi Toyota Ayato Kawashima Yoshiaki Hattori Yukio Hashimoto Hiroshi Yamashita 《International Journal of Heat and Mass Transfer》2010,53(15-16):3067-3074
Plasma was generated in water by irradiation at high frequency of 13.56 MHz, and the behavior of bubbles including the plasma was observed by a high-speed camera. The generation pattern of the bubbles was classified into four types according to liquid temperature and supplied power. Conducting the simulation, the maximum temperature in the bubble was found to be from 3500 K to 4300 K, and the decomposition of water molecule occurred. The gas in the bubble was found to become high ratio of hydrogen. The phenomenon can be regarded as a film boiling of exceptionally high heat flux. 相似文献