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151.
Structure and properties of starch and water soluble polysaccharides (WSP) from sugary (su) endosperm of rice were examined. The su starch contained more amylose and had a somewhat higher ratio of the short chains to the long chains of amylopectin than normal starch. The WSP consisted of short α-1, 4-chains and their average degree of polymerization was 8.6 glucose units. Susceptibility of the su starch to crude Rh. glucoamylase was higher than that of the normal. The initial and final temperatures and heat of gelatinization of the su starch granules were much lower than those of the normal ones. 相似文献
152.
Satoshi Someya Satoshi Yoshida Takahide Tabata Koji Okamoto 《International Journal of Heat and Mass Transfer》2009,52(19-20):4236-4243
The basic characteristics of the reacting mixing flow of two streams were investigated. The reaction between aqueous solutions of ammonia and acetic acid, which produces ammonium acetate, was investigated in terms of the effect on the fluid–fluid interface of the mixing flow relative to fluids that did not react. The reaction between these solutions was negligibly exothermic, and there were minimal differences in density. The velocity field in the reacting mixing flow was quantitatively measured using high-speed time-resolved particle image velocimetry (PIV) and the behavior of the mixing flow was qualitatively investigated using laser-induced fluorescence (LIF). The jet width, the velocity field, the kinetic energy and the turbulent intensities are qualitatively estimated and discussed. It was found that the chemical reaction resulted in the suppression of the mixing flow. 相似文献
153.
Wenxi Tian Yuki Ishiwatari Satoshi Ikejiri Masanori Yamakawa Yoshiaki Oka 《Nuclear Engineering and Design》2009,239(11):2382-2390
In present study, the collapse of void bubble in liquid has been simulated using moving particle semi-implicit (MPS) code. The liquid is described using moving particles and the bubble–liquid interface was set to be vacuum pressure boundary without interfacial heat mass transfer. The topological shape of bubble can be traced according to the motion and location of interfacial particles. The time dependent bubble diameter, interfacial velocity and bubble collapse time were obtained under wide parametric range. The comparison with Rayleigh and Zababakhin's prediction showed a good agreement which validates the applicability and accuracy on MPS method in solving present momentum problems. The potential void induced water hammer pressure pulse was also evaluated which is instructive for further material erosion study. The bubble collapse with non-condensable gas has been further simulated and the rebound phenomenon was successfully captured which is similar with vapor-filled cavitation phenomenon. The present study exhibits some fundamental characteristics of void bubble hydrodynamics and it is also expected to be instructive for further applications of MPS method to complicated bubble dynamics problems. 相似文献
154.
Satoshi Tanaka Atsushi Makiya Zenji Kato Keizo Uematsu 《Journal of the European Ceramic Society》2009,29(5):955-959
A rotating magnetic field was used to fabricate c-axis oriented zinc oxide. The influence of rotating speed on orientation structure was also examined. The aligned axes had the largest diamagnetic susceptibility, which axis was difficult to align with a static magnetic field. In c-axis oriented ZnO, the degree of orientation (Lotgering factor) in the green compact ranged from 0.2 to 0.5 along c-axis. The Lotgering factor increased with rotating speed. For all samples with the rotating magnetic field, the degrees of orientation increased up to above 0.9 after sintering at 1573 K. 相似文献
155.
Sunnam Kim Wataru Inoue Satoshi Hirano Ryohei Yagi Yutaka Kuwahara Tomonari Ogata Seiji Kurihara 《Polymer》2014
Three type polymers containing the same azobenzene side chain group with different backbone structures, poly(DMAz6Fm), poly(DMAz6It) and poly(MAz6Ac) derived respectively from fumaric acid, itaconic acid and acrylic acid, were synthesized. The dependence of photo-response properties on the polymeric architecture was investigated for the solutions and films. By irradiation of the linearly polarized light (436 nm), uniaxial orientations of the thin films were induced and anisotropic properties were investigated by measurements of the order parameters and birefringence values. 相似文献
156.
157.
The authors propose a new design concept for controlling the deflection of a micro-membrane with the aid of its thickness distribution for realizing a prescribed design in the MEMS. As an example, the authors treat a micro air pump that comprises a micro-membrane. The membrane is actuated by an electrostatic force. The membrane deflects and thus the deflection is influenced by the air pressure and the electrostatic field. This is a highly complicated system. To find out a proper thickness distribution, the authors use the genetic algorithm that is appropriate to reduce the searching space of solution. 相似文献
158.
A series of star-shaped poly(lactic acid)s with carboxylic acid terminal groups have been synthesized by direct poly-condensation of lactic acid in the presence of a poly-carboxylic acid core molecule with triphenylphosphonium trifluoromethanesulfonate (TPP-T) catalyst.These star-polymers had thermal properties not very much different from those of star-shaped poly(lactic acid) with hydroxyl terminal groups and linear poly(lactic acid), irrespective of the structure of the core molecule and number of polymer arms. Solubility and degradability of these star-polymers were, however, greatly enhanced compared to those of star-polymers with hydroxyl terminal groups and increased depending on the number of polymer arms. From the star-shaped polymers, a variety of ammonium salts and the corresponding carboxyamides were successfully prepared. 相似文献
159.
A perpendicular mesoporous platinum film is used as a model electrode to clarify the effectiveness of catalysts inside agglomerates of fuel cell catalyst layers on the basis of experimental facts. The analysis clarifies that: (i) Pt surface even apart from Nafion ionomer phase can be electrochemically active; (ii) its response is different from that of the surface covered with ionomer; and (iii) ionic resistance in pores filled with pure water is too high (ca. 0.18 MΩ cm) for fuel cell reactions to smoothly occur. We conclude that such catalysts in pores filled with pure water are ineffective for fuel cell reactions due to the high ionic resistance, though their catalytic activity is possibly higher than that of the catalysts covered with Nafion. 相似文献
160.
Koh Matsumoto Kazutada Ikenaga Jun Yamamoto Kazuki Naito Yoshiki Yano Akinori Ubukata Hiroki Tokunaga Tadanobu Arimura Katsuaki Cho Toshiya Tabuchi Akira Yamaguchi Yasuhiro Harada Yuzaburo Ban Kousuke Uchiyama 《半导体学报》2011,32(1):21-23
Growth rate has a direct impact on the productivity of nitride LED production.Atmospheric pressure growth of GaN with a growth rate as high as 10μm/h and also Al0.1Ga0.9N growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described.XRD of(002) and(102) direction was 200 arcsec and 250 arcsec, respectively.Impact of the growth rate on productivity is discussed. 相似文献