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71.
This paper proposes a novel method for color restoration that can effectively apply accurate color based on spectral information to a segmented image using the normalized cut technique. Using the proposed method, we can obtain a digital still camera image and spectral information in different environments. Also, it is not necessary to estimate reflectance spectra using a spectral database such as other methods. The synthesized images are accurate and high resolution. The proposed method effectively works in making digital archive contents. Some experimental results are demonstrated in this paper. 相似文献
72.
Effect of Ultrasonication on the Microstructure and Tensile Elongation of Zirconia-Dispersed Alumina Ceramics Prepared by Colloidal Processing 总被引:1,自引:0,他引:1
Tohru S. Suzuki Yoshio Sakka Keishi Nakano Keijiro Hiraga 《Journal of the American Ceramic Society》2001,84(9):2132-2134
To obtain dense, fine-grained ceramics, fine particles and advanced powder processing, such as colloidal processing, are needed. Al2 O3 and ZrO2 particles are dispersed in colloidal suspensions by electrosteric repulsion because of polyelectrolyte absorbed on their surfaces. However, additional redispersion treatment such as ultrasonication is required to obtain dispersed suspensions because fine particles tend to agglomerate. The results demonstrate that ultrasonication is effective in improving particle dispersion in suspensions and producing a homogeneous fine microstructure of sintered materials. Superplastic tensile ductility is improved by ultrasonication in preparing suspensions because of the dense and homogeneous fine microstructure. 相似文献
73.
Kenichi Ide Masahiko Nakade Tohru Takahashi Takenori Nakajima 《Electrical Engineering in Japan》2012,178(1):1-10
Much of oil‐filled (OF) cable has been used for a long time as 66‐ to 500‐kV extrahigh‐voltage cable. Sometimes we can see extremely degraded tan δ oil (several tens of percent of tan δ, for example) in joint boxes, etc. The values of tan δ calculated by a simple combination model of paper/oil show that the oil‐impregnated paper with such a high tan δ oil likewise has an extremely high tan δ, which must result in thermal breakdown. However, such an event has not taken place up to the present in actually operated transmission lines. This fact suggests that some mechanism for the suppression of tan δ has acted in the paper insulation impregnated with degraded tan δ oil. Therefore, we investigated in detail the tan δ characteristics of paper impregnated with extremely high tan δ oil. In addition, based on the investigation results, we developed a method for simulation of heat generation by dielectric loss in an OF cable joint (which has degraded tan δ oil). © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(1): 1–10, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21184 相似文献
74.
Ludi Xu Degui Zhu Yunlong Liu Tohru S. Suzuki Byung-nam Kim Yoshio Sakka Salvatore Grasso Chunfeng Hu 《Journal of the European Ceramic Society》2018,38(10):3417-3423
Oxidation resistance of textured Ti3AlC2 ceramics was measured in the temperature range 1273–1573?K. It was found that the oxidation was markedly anisotropic and the samples exhibited a better oxidation resistance when tested along a direction transverse to the c-axis. This behavior was attributed to the rapid diffusion of Al within its basal planes to form a passivating Al2O3 scale and it respected Ellingham diagrams. The scales formed had different compositions depending on the testing direction; this response was clearly resulting from the crystallographic orientation. Even at 1473?K after 20?h exposure, the samples tested in a direction transverse to the c-axis showed a reduced weight gain which was 45 times lower than one seen on a basal plane. 相似文献
75.
Rapid Reconstitution of Biosynthetic Machinery for Fungal Metabolites in Aspergillus oryzae: Total Biosynthesis of Aflatrem 下载免费PDF全文
Koichi Tagami Dr. Atsushi Minami Ryuya Fujii Dr. Chengwei Liu Dr. Mizuki Tanaka Prof. Dr. Katsuya Gomi Prof. Dr. Tohru Dairi Prof. Dr. Hideaki Oikawa 《Chembiochem : a European journal of chemical biology》2014,15(14):2076-2080
Reconstitution of the biosynthetic machinery for fungal secondary metabolites in Aspergillus oryzae provides an opportunity both for stepwise determination of the biosynthetic pathways and the total biosynthesis of fungal natural products. However, to maximize the utility of the reconstitution system, a simple and rapid strategy for the introduction of heterologous genes into A. oryzae is required. In this study, we demonstrated an effective method for introducing multiple genes involved in the biosynthesis of fungal metabolites by using the expression vectors pUARA2 and pUSA2, each of which contains two cloning sites. The successful introduction of all the aflatrem biosynthetic genes (seven genes in total) after two rounds of transformation enabled the total biosynthesis of aflatrem. This rapid reconstitution strategy will facilitate the functional analysis of the biosynthetic machinery of fungal metabolites. 相似文献
76.
Tohru Sekino Toshio Nakajima Satoru Ueda Koichi Niihara 《Journal of the American Ceramic Society》1997,80(5):1139-1148
High-density nickel–dispersed-alumina (Al2 O3 /nickel) composites with superior mechanical properties were obtained by the hydrogen reduction and the hot pressing of alumina–nickel oxide (Al2 O3 /NiO) mixed powders. The mixtures were prepared by using NiO or nickel nitrate (Ni(NO3 )2 · n H2 O) as a dispersion source of nickel metal. Microstructural investigations of the composite fabricated using nitrate powder revealed that fine nickel particles, } 100 nm in diameter, dispersed homogeneously at the matrix grain boundaries, forming the intergranular nanocomposite. High strength (.1 GPa) and high-temperature hardness were registered for the composite that contained a small amount of nickel dispersion. The ferromagnetic properties of nickel, such as high coercive force, were observed, because of the fine magnetic dispersions, which indicates a functional value of structural composites. 相似文献
77.
Aiping Wu Takenori Fujiwara Masa-aki Kakimoto Yoshio Imai Tohru Kubota Mitsumasa Iwamoto 《Reactive and Functional Polymers》1996,30(1-3):361-365
The electrical properties of poly(p-phenylene vinylene) (PPV) Langmuir-Blodgett (LB) films were investigated, wherein transparent indium-tin oxide (ITO) and aluminum (Al) were used as the electrodes. Their I–V characteristics depended strongly on the thickness of PPV LB film, and the electric conductivity of the PPV LB film was in the range of 10−2–10−15 (S/cm). Their C–V characteristics showed that the capacitance was reversibly proportional to the thickness of PPV LB film and was kept constant when the applied voltage changed from −1.0 V to +1.0 V. These results indicated that PPV LB film was an insulator in this range of applied voltage without doping. Under forward bias, yellow-green light emission was observed in PPV LB film based light emitting diodes (LEDs), the highest light emission reached more than 100 cd/m2 in the case that PPV LB film was deposited for 80 layers, i.e. a ITO/PPV(80L)/Al device. 相似文献
78.
Seiichiro Imamura Tohru Nakai Hiroyoshi Kanai Takeshi Shiono Kazunori Utani 《Catalysis Letters》1996,39(1-2):79-82
Titania-silica mixed oxide was prepared by hydrolyzing tetraethyl orthosilicate and tetraisopropyl titanate(IV) with a mixture of ethanol and 0.01 N aqueous acetic acid. Surface Ti content, BET surface area, and the number of acid sites increased with an increase in 0.01 N aqueous acetic acid. Thus hydrolysis of both alkoxides occurred simultaneously with a large amount of the acetic acid solution, and there was extensive interaction between TiO2 and SiO2 phases. With small amount of 0.01 N aqueous acetic acid, however, titanium hydroxide was first formed and, then, it was covered with the silica phase produced in a later stage of the hydrolysis. Increase in the acetic acid solution also led to the formation of a large amount of tetrahedral Ti species, which were active for the epoxidation of oct-1-ene usingt-butyl hydroperoxide as an oxidant. 相似文献
79.
80.