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61.
Yuji Tatemoto Yoshiyuki Bando Keiji Yasuda Yoshitaka Senda Masaaki Nakamura 《Drying Technology》2001,19(7):1305-1318
The drying characteristics of porous material in fluidized bed were examined theoretically and experimentally. The brick ball was used as the sample and immersed in the fluidized bed. The glass beads were used as the fluidizing particles and the particle diameters were changed. When the pore diameter of sample was relatively large, the fluidizing particles were adhered on the sample surface. In the theoretical analysis, the heat and mass transfers in adhered particle layer were considered. The fluidizing particles were adhered on the sample surface during the earlier period of drying. The sample temperature largely decreased when the mass of adhered particle decreased. The calculated results are in good agreement with experimental data. The diameter of fluidizing particle had a small effect on the drying time. The excess increments in drying gas temperature hardly contributed to shortening the drying time. 相似文献
62.
Liping Yao Zhong Zeng Hiroshi Mizuseki Yoshiyuki Kawazoe 《International Journal of Thermal Sciences》2010,49(12):2413-2418
Convection control of three-dimensional thermocapillary flow by a rotating magnetic field (RMF) was simulated numerically, and the RMF infinite and RMF Φ1–Φ2 models were compared. The results of using both RMF models demonstrate that the transverse RMF stirs convection in an azimuthal direction and suppresses convection in the axial direction, which is helpful for the three-dimensional melt convection to become axisymmetric. Compared to the RMF Φ1–Φ2 model, however, the over-simplified RMF infinite model leads to a relatively large deviation. With the same magnetic field (7 mT, 50 Hz), the RMF infinite model results in a larger azimuthal velocity and a smaller axial velocity. 相似文献
63.
Yuji Tatemoto Yoshiyuki Bando Koji Oyama Keiji Yasuda Masaaki Nakamura Yasuhiro Sugimura Masahito Shibata 《Drying Technology》2001,19(7):1287-1303
The effects of operational conditions on the drying performance in closed superheated steam drying were examined theoretically and experimentally. The vapor generated from the sample was circulated in the drying chamber. In the theoretical analysis, the replacement of air with vapor in drying chamber and the convective vapor transfer in sample were considered. At the start of drying, the drying chamber was filled with air. As the drying proceeded, the air was replaced with the vapor generated from sample. The calculated results explained the characteristics of experimental data. The pore diameter of sample had little effect on the drying characteristics. During the internal evaporation period, the evaporation occurred in the narrow zone, which moved from the surface to the bottom of sample. The convective vapor transfer in sample had a significant influence on the drying performance. The excess increments in temperature and velocity of drying gas hardly contributed to shortening the drying time. 相似文献
64.
Meisen Li Yoshiyuki Bando Ryo Tanigawara Toru Kamiya Keiji Yasuda Masaaki Nakamura 《加拿大化工杂志》2001,79(4):602-607
The effects of operation conditions on the flow behaviour in gas–liquid countercurrent trickle bed biofilter were experimentally examined. In order to prevent gas channelling in the biofilter, packings with a relatively large void fraction, which have a role to maintain a high void fraction in the bed, were added. The gas and liquid velocities of the packed structure and the packings were changed, and the residence time distributions (RTDs) of the gas and liquid were measured. It was found that the addition of void supporters was very effective in the suppression of gas channelling. 相似文献
65.
Superhydrophobic/superhydrophilic micropatterning on a carbon nanotube (CNT) film has been achieved using a laser plasma-type hyperthermal atom beam facility, which produces a small amount of damage and generates a highly anisotropic beam. Fluorination and oxidation on CNT films by exposure to fluorine-atom and oxygen-atom beams caused superhydrophobic and superhydrophilic surfaces, respectively, while maintaining the as-grown fibrous forms of the CNT films. Micropatterned oxidation on CNT films without using photoresists created superhydrophilic microdots and microchannels. 相似文献
66.
Emi Hasegawa Hiroshi Suzuki Kananko Kameyama Yoshiyuki Komoda Hiromoto Usui 《Advanced Powder Technology》2009,20(2):139-144
In this paper, a model estimating the time-dependent distribution of cluster size consisting of fine particles in Newtonian molten polymer was proposed. The present model for agglomerative suspension was developed based on Usui’s thixotropy model, derived by taking the balance between shear breakup, shear coagulation and Brownian coagulation processes. The analysis was applied to the experimental results for silica/(ethylene methyl-meta acrylate copolymer) suspensions. The time variations of cluster size distributions, of viscosities and of the mean numbers of particles in a cluster were calculated and the results were compared with experimental results for the cases of shear rates from 0.2 to 10 s?1 when the solid volume fraction was set at 0.15. From the results, it was found that the present model can estimated the steady state values of the slurry viscosity and the mean particle numbers in a cluster as well as Usui’s original model. However, the model could not sufficiently express the time variation of rheological characteristics due to the over-estimation of the contribution of shear rate when the cluster size is small. 相似文献
67.
Hiromi Yoshida Takaaki Tanigawa Naoko Yoshida Isoko Kuriyama Yuka Tomiyama Yoshiyuki Mizushina 《Food chemistry》2011
Endogenous tocochromanols in extracted lipids from rice brans of the five cultivars were determined by high-performance liquid chromatography, and were investigated in relation to the fatty acid (FA) distribution of triacylglycerols (TAG) and phospholipids (PL). The dominant tocols were α-tocopherol and γ-tocotrienol, followed by α-tocotrienol and with much smaller amounts of γ-tocopherol and δ-tocotrienol. The lipids of these rice brans comprised mainly TAG (80.6–86.0 wt.%), free FA (4.2–9.0 wt.%), and phospholipids (5.5–6.7 wt.%), whilst other components were also detected in minor proportions (0.2–2.1 wt.%). The PL components included phosphatidyl choline (31.8–46.8 wt.%), phosphatidyl ethanolamine (25.0–38.9 wt.%) and phosphatidyl inositol (20.2–23.2 wt.%). Comparison of these different cultivars showed, with a few exceptions, no significant differences (P > 0.05) in FA distribution. FA distribution of TAG among the five cultivars was evident in the rice brans: unsaturated FA were predominantly concentrated at the sn-2 position and saturated FA primarily occupying the sn-1 or sn-3 position. These results suggest that the tocopherol content, lipid component, and FA distribution in rice brans are not dependent on the cultivation areas during the growing season. 相似文献
68.
69.
Yasuhito Ishigaki Yuka Nakamura Teruaki Takehara Noriko Nemoto Takayuki Kurihara Hironori Koga Hideaki Nakagawa Tsutomu Takegami Naohisa Tomosugi Shichiro Miyazawa Susumu Kuwabata 《Microscopy research and technique》2011,74(5):415-420
Ionic liquid is a kind of salt that stays in a molten state even at room temperature. It does not vaporize at all in vacuum and facilitates electrical conductivity to the sample surfaces for observations with a scanning electron microscope (SEM). In this study, we used an ionic liquid in SEM for the first time to observe fixed human culture cells. The condition for the cell culture using wrapping sheets and SEM settings were varied to elucidate the optimized protocol. Compared to samples prepared by the conventional way, the ionic liquid‐treatment of samples gave SEM images of the cellular ultra structures in more detail, enabling observation of microvilli that made bridges between separated cells. In addition, the ionic liquid treatment is less time consuming as well as less laborious compared with the conventional way that includes dehydration, drying, and conductivity treatments. Totally, we concluded the ionic liquid is a useful reagent for SEM sample preparation. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc. 相似文献
70.
Pu J Nemoto S 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(2):339-344
The off-axis and on-axis spectra in the far zone of an aperture for the case in which a particular class of partially coherent light with a broad spectrum is diffracted by an aperture are studied. It is shown that the spectrum in the far zone is generally different from that at the aperture; i.e., the spectrum is split into two or more peaks. Moreover, the spectrum varies with the diffractive angle. For a fixed diffractive angle, the spectral shift, defined as the difference between the frequencies at which the observed spectrum and the spectrum at the aperture take their maximum, shows a gradual change with the change in the coherence at the aperture. However, as the coherence reaches some critical values, the spectral shift exhibits a rapid transition; i.e., spectral switch occurs. The coherence that causes the spectral switch to take place is different for different diffractive angles. Therefore we propose a new kind of 1 x N spectral switch, where N detectors (output ports) are placed at different diffractive angles in the far zone, and the spectral shifts at different detectors are measured. By adjusting the coherence of the aperture (input port) to the desired values, we obtain a rapid transition of the spectral shift in the desired output ports. 相似文献