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101.
Kazuhiko Misawa Isao Matsuda Naoyuki T. Hashimoto Roy Lang 《Journal of Modern Optics》2013,60(16-18):2685-2692
Abstract A new optical telecommunication method combining time and frequency domain multiplexing is proposed using phase-controlled femtosecond pulses. Each pulse in a pulse train can be used as a data packet with data bits in the frequency domain. We call the new principle ‘wave packet engineering’, which adjusts the amplitude and phase of the wave function in device materials arbitrarily by controlling the spectral phase of femtosecond pulses. The optical phase-to-amplitude converter is demonstrated with organic dye molecules, in which the phase information in the phase-modulated pulses can be demodulated into the luminescence intensity. The luminescence intensity from cyanine dye molecules is observed to be chirp dependent, and is explained quantum mechanically in terms of coherent population transfer. The design principle of the device using semiconductor coupled quantum nanostructures is also discussed in terms of wave packet engineering. 相似文献
102.
Eiji Obarsawa Zdenek Slanina Kazuhiko Honda Xiang Zhao 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(2):259-270
Abstract Stone-Wales rearrangement may be considered to consist of two contiguous steps of olefin-carbene 1,2-C-C bond shift. Computational study on this mechanism led to high activation energies comparable to the bond dissociation energies of C-C bonds in fullerenes and their precursors. the possibility of passing through triplet transition state is denied on computational grounds. 相似文献
103.
Kazuhiko Izawa Yuriko Uchida Kiyoshi Ohkubo Masayoshi Totsuka Hiroki Sono Kotaro Tonoike 《Journal of Nuclear Science and Technology》2013,50(11):1043-1047
The possibility of criticality of fuel debris in a form of uranium dioxide (UO2)–concrete mixture is evaluated by calculating the infinite multiplication factor (k ∞) for a study of criticality control on the fuel debris generated through the molten core concrete interaction in a severe accident of a light water reactor. The infinite multiplication factor can be greater than unity, which means that handling of the mixture is subject to criticality control. This paper shows that concrete provides efficient neutron moderation and points out the necessity of further investigations on the criticality of UO2–concrete system for actual handling of fuel debris. 相似文献
104.
A macroazoinitiator (MAI) containing a poly(ethylene oxide) (PEO) block was used with a methyl methacrylate monomer to prepare polymer particles in ethanol/H2O solutions. The effects of the monomer/MAI ratio (RMI) and H2O content in the solutions on the molecular weight, particle diameters, and chemical structure of the resulting polymer particles were investigated. The reaction mixtures showed three kinds of states, which were milky colloid solutions, macrogels and/or precipitations, and clear solutions. The colloid solutions were obtained in the solutions with an H2O content of about 50–90 vol % and a RMI of 20–400. In the colloid solutions, core–shell nanospheres consisting of PEO shells and poly(methyl methacrylate) (PMMA) cores were predominantly obtained. In the specific conditions close to the area of gel and/or precipitation formation, particles connected about 0.5–5 μm in length were obtained. Multiblock copolymers nanospheres tended to be obtained with lower RMIs, and PMMA‐PEO‐PMMA tri‐bloc and/or PMMA‐PEO di‐block copolymer nanospheres were obtained with higher RMIs. The solubility of the monomer and the generated polymer in solutions may have affected the polymerization development and the state of the products. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
105.
Hidenori Yahiro Kunimasa Sagata Tetsuya Yamamoto Kazuhiko Saiki Makiko Asamoto Hiroyuki Yamaura 《Catalysis Letters》2008,124(3-4):233-237
Among the supported Cu–FeOx catalysts, Al2O3-supported Cu–FeOx catalyst exhibited the highest activity for WGS reaction. The enhancement of the catalytic activity by adding FeOx to Cu/Al2O3 could be interpreted by the two possibilities; one is the formation of highly dispersed Cu0 and the other is the participation of reduced FeOx in WGS reaction in the presence of Cu0. 相似文献
106.
107.
Ambipolar organic field effect transistors with heterojunction structures have been fabricated using a biphenyl-capped thiophene oligomer (BP2T) and a naphthalene derivative (GS1b) for p-type and n-type organic semiconductors, respectively. Asymmetric electrode structures with Au source and Al-Li drain resulted in better performances than that of a symmetric device due to improved electron injection by the low work-function drain metal. 相似文献
108.
以聚合MDI作为增稠剂改性团状模塑料(BMC),考察了聚合MDI用量增稠不饱和聚酯树脂(UP)和聚合MDI增稠不同质量比的不饱和聚酯树脂(UP)/环氧乙烯基树脂(VE)的混杂树脂对BMC物理性能的影响。结果表明,聚合MDI的加入能改善BMC的物理性能,聚合MDI增稠VE时,当质量分数为6%时,BMC的拉伸、弯曲和冲击强度均达到最大,收缩率最小;聚合MDI增稠UP/VE混杂树脂时,UP/VE质量比在25/45到35/35时,能获得最小的收缩率和力学性能。 相似文献
109.
Mechanisms of hydrogen sulfide removal with steel making slag 总被引:1,自引:0,他引:1
K Kim S Asaoka T Yamamoto S Hayakawa K Takeda M Katayama T Onoue 《Environmental science & technology》2012,46(18):10169-10174
In the present study, we experimentally investigated the removal of hydrogen sulfide using steel-making slag (SMS) and clarified the mechanism of hydrogen sulfide removal with the SMS. The results proved that SMS is able to remove hydrogen sulfide dissolved in water, and the maximum removal amount of hydrogen sulfide per unit weight of the SMS for 8 days was estimated to be 37.5 mg S/g. The removal processes of hydrogen sulfide were not only adsorption onto the SMS, but oxidation and precipitation as sulfur. The chemical forms of sulfide adsorbed onto the SMS were estimated to be sulfur and manganese sulfide in the ratio of 81% and 19%, respectively. It is demonstrated here that the SMS is a promising material to remediate organically enriched coastal sediments in terms of removal of hydrogen sulfide. Furthermore, using SMS is expected to contribute to development of a recycling-oriented society. 相似文献
110.
Joao Gari da Silva Fonseca Takashi Oozeki Takumi Takashima Gentarou Koshimizu Yoshihisa Uchida Kazuhiko Ogimoto 《Progress in Photovoltaics: Research and Applications》2012,20(7):874-882
The development of a methodology to forecast accurately the power produced by photovoltaic systems can be an important tool for the dissemination and integration of such systems on the public electricity grids. Thus, the objective of this study was to forecast the power production of a 1‐MW photovoltaic power plant in Kitakyushu, Japan, using a new methodology based on support vector machines and on the use of several numerically predicted weather variables, including cloudiness. Hourly forecasts of the power produced for 1 year were carried out. Moreover, the effect of the use of numerically predicted cloudiness on the quality of the forecasts was also investigated. The forecasts of power production obtained with the proposed methodology had a root mean square error of 0.0948 MW h and a mean absolute error of 0.058 MW h. It was also found that the forecast and measured values of power production had a good level of correlation varying from 0.8 to 0.88 according to the season of the year. Finally, the use of numerically predicted cloudiness had an important role in the accuracy of the forecasts, and when cloudiness was not used, the root mean square error of the forecasts increased more than 32%, and the mean absolute error increased more than 42%. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献