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81.
Simulation research on monomer agglomeration of nonmetallic inclusions in steel with a diffusion limited aggregation model 总被引:1,自引:0,他引:1
Hong Li Linxin Ning Juan Wen Jiongming Zhang Yasushi Sasaki Mitsutaka Hino 《北京科技大学学报(英文版)》2006,13(2):117-120
The monomer agglomeration of nonmetallic inclusions was simulated with a diffusion limited aggregation (DLA) model of the fractal theory. The simulation study with a random two-dimensional diffusion was carried out. The results indicate that the DLA model can be used for the simulation of agglomeration behavior of the cluster-type inclusions. The morphology of clusters was observed with SEM and compared with the simulated agglomerates. The modelling procedure of the DLA model is applicable for the agglomeration process. The uncertainty of agglomeration process and the persuasive average agglomerative ratio was analyzed. The factors about the agglomerative ratio with the collision path distance and the size of particles or seed were discussed. The adherence of the nonmetallic inclusions on the dam, the weir and the walls of a tundish, and the absorption of inclusions by stopper or nozzle were also discussed. 相似文献
82.
83.
Akinori Zukeran Yasushi Ikeda Yoshiyasu Ehara Tairo Ito Takeo Takahashi Hitomi Kawakami Takeshi Takamatsu 《Electrical Engineering in Japan》2000,130(1):30-37
Improving the collection efficiency for particles smaller than 1 μm on every precipitator is important. We sought to improve the collection of these particles on an ESP due to particle agglomeration. Particles are charged by ac corona discharge in a precharger and agglomerated by a dc electric field in an agglomerator downstream of the precharger. Diesel exhaust particles were used as particulate matter for the experiments. The distribution of particle size was measured using a particle counter and a scanning electron microscope. By these methods, particles as small as 0.01 μm could be counted. Results showed the agglomeration between particles at ac corona discharge operating mode. The concentration of particles smaller than approximately 0.35 μm decreases, and that of particles larger than approximately 0.35 μm increases in the agglomerator. The agglomeration rate increases with increasing applied voltage, then saturates. These results may be due to the size distribution and to decrease of concentration by agglomeration. © 1999 Scripta Technica, Electr Eng Jpn, 130(1): 30–37, 2000 相似文献
84.
Kiyoshi Minoura Shigeaki Mizushima Yasushi Asaoka Ichiro Ihara Eiji Satoh Sayuri Fujiwara Yasuhisa Itoh 《Journal of the Society for Information Display》2008,16(1):129-136
Abstract— A novel reflective color LCD without polarizers has been developed using a PDLC film and a retro‐reflector. Bright color images including moving images are achievable with ambient light. This novel LCD will enable the new application area of electronic paper. 相似文献
85.
Tae Ho Lee Hirokazu Aoki Yasushi Sugano Makoto Shoda 《Journal of Bioscience and Bioengineering》2000,89(6):545
The production of dye-decolorizing peroxidase (DyP) was investigated by cultivating Geotrichum candidum Dec1 using molasses as a carbon source. Molasses at concentrations greater than 10 g·l−1 was found to increase the decolorization activity of the culture broth toward dye, reactive blue 5 mainly because the amount of enzyme produced was enhanced. However, complete inhibition of DyP activity by molasses was observed at the concentration of 20 g·l−1, indicating that the inhibitory effect of molasses on the culture broth activity to decolorize the dye was involved. When the culture broth was diluted 25 times, the dye-decolorizing activity was 7 times as much as that of non-diluted culture broth. The molasses fractions separated by gel chromatography (300–400 ml and 400–500 ml fractions) completely inhibited the purified DyP. On the basis of these results, we propose a scheme to control both positive and negative effects of molasses on the dye decolorization process. 相似文献
86.
This paper describes an efficient contention resolution algorithm and its distributed implementation for large capacity input queuing cross-connect switches, which will establish virtual paths in future broadband ATM networks. The algorithm dynamically allocates sending time to cells held in input queues when no contention is indicated in the designated output ports. An expression for the mean delay and the cell loss probability for random traffic are derived through an approximate analysis. Input cells are served on a first-come, first-served basis as conventional contention resolution algorithms whose throughput saturates at 58 per cent because of head of line blocking in input queues. The proposed algorithm achieves a maximum throughput of 76 per cent. 相似文献
87.
T. KATO Y. TANAKA T. HIRATA S. KUMAMOTO K. MIYAZAKI 《Journal of Materials Science Letters》1997,16(21):1771-1773
88.
Experiments with a single fire source were carried out in crosswinds in order to elucidate the correlation between temperature rise and velocity along an inclined fire plume axis. A circular propane burner with a diameter of 0.2 m was used as a model fire source. The temperature and velocity were measured along the inclined fire plume axis, and these were compared with fire plume data obtained in a calm condition. An empirical formula to represent the correlation of the temperature rise and velocity was developed. The values of empirical coefficients and exponents were derived from the experimental results of the circular burner. In order to verify the availability of the proposed empirical formula, the comparison was carried out with the data obtained from square and/or rectangular burners. 相似文献
89.
采用无偏振片反射式LCD及超低功耗驱动技术制造移动显示器件 总被引:1,自引:1,他引:0
Kiyoshi Minoura Yasushi Asaoka Eiji Satoh Takashi Satoh Ichiro Ihara Sayuri Fujiwara Akio Miyata Yasuhisa Itoh Seijiro Gyoten Noboru Matsuda Yasushi Kubota 代永平 《现代显示》2010,(7):5-9,35
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。 相似文献
90.
Yasushi Endo Riichiro Usuki Takashi Kaneda 《Journal of the American Oil Chemists' Society》1985,62(9):1387-1390
To understand the mechanism of the antioxidant effect of chlorophyll on the autoxidation of oils in the dark, antioxidant
activities of several derivatives of chlorophyll were compared. Antioxidant activities were observed in chlorophyll derivatives
such as protopor-phyrin methyl ester and its magnesium chelated compound. Porphyrin seems to be an essential chemical structure
for the antioxidant activity of chlorophyll. Chlorophyll did not decompose the hydroperoxides, but reduced free radicals such
as 1,1-diphenyl-2-picrylhydrazyl. Electron spin resonance spectrum of the π-cation radical was recorded during the oxidation
of chlorophyll in methyl linoleate solution. These observations suggest that chlorophyll may act as a hydrogen donor to break
the chain reaction. 相似文献