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91.
T. Sato T. Murakami T. Endo M. Shimada K. Komeya T. Kameda M. Komatsu 《Journal of Materials Science》1991,26(7):1749-1754
Corrosion behaviour of Si3N4 ceramics containing Y2O3, Al2O3 and AIN as sintering aids was investigated under hydrothermal conditions at 200–300 C and saturated vapour pressures of water for 1–10 days. Hydrothermal corrosion resulted in the dissolution of the Si3N4 matrix and the formation of a product layer consisting of the original grain-boundary phases and hydrated silica. The dissolution rate of Si3N4 ceramics decreased with decreasing crystallinity of the grain-boundary phase. The dissolution rate could be adequately described by a parabolic plot in the initial stage of the reaction. The apparent activation energies were 83.5–108 kJ mol–1, and the bending strength of the corroded samples decreased from 600 to 400 MPa in the initial stage of the reaction upto a weight loss of 0.004 g cm–2, and then was almost constant up to a weight loss of 0.012 g cm–2. 相似文献
92.
Sohei Sato Hironori Hondoh Satoru Ueno 《Journal of the American Oil Chemists' Society》2021,98(3):269-280
Fat bloom in chocolate is a substantial problem that affects its sensory properties, such as texture and appearance. This phenomenon is because of diffuse light reflection on a roughened surface of chocolate, caused by structural changes of fat crystals subjected to various temperature conditions. The purpose of this study is to characterize the fat bloom formed through gradual two-step cooling after exposure to temperatures (35–37 °C) slightly above the cocoa butter Form βV melting point (33.8 °C). To clarify the fat bloom formation process, the structural changes in cocoa butter and on the chocolate surface, at the dynamic thermal condition for bloom formation, was investigated using X-ray diffraction (XRD), fluorescence light microscopy, and scanning electron microscopy (SEM). The results revealed that an entirely light brown fat bloom occurred, even in the absence of the Form βVI or other polymorphic transformation. Microscopic observation showed that the light brown appearance was because of the porous structure on the chocolate surface. This porous structure was formed by liquid oil moving inside of chocolate from the surface. The formation of a coarse network and the subsequent de-oiling, because of movement of unsolidified liquid fat into the chocolate, appeared to be the main causes of bloom formation. Therefore, a coarsened fat network and oil movement besides the conventional principles of polymorphic transformation of cocoa butter should be considered. 相似文献
93.
Alloy 903 and Alloy 909 are well-known Fe-Co-Ni-Al-Ti-Nb alloys with controlled low thermal expan-sion, but they have some
properties that can be improved. To improve stress-accelerated grain boundary oxidation embrittlement of Alloy 903 and instability
of theγ phase of alloy 909, two new alloys with good stress-rupture ductility, high creep-rupture strength, high tensile strength
at high temperature, and good controlled thermal expansion were developed. These property improvements were accomplished by
the combination of optimizing the Fe-Co-Ni ratio of the matrix and stabilizing theγ phase with the addition of aluminum. 相似文献
94.
The structure of internal oxide layers in decarburized sheet was studied using a newly developed electrochemical method. Dissolving
potential profiles indicated the amount of fayalite (Fe2SiO4) and silica (SiO2) in the layers. The quantitative data for the contents of fayalite and silica in the internal oxide layers can be easily
obtained by this method. 相似文献
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98.
The plasmodium of Physarum polycephalum is a unicellular and multinuclear giant amoeba that has an amorphous cell body. To clearly observe how the plasmodium makes decisions in its motile and exploratory behaviours, we developed a new experimental system to pseudo-discretize the motility of the organism. In our experimental space that has agar surfaces arranged in a two-dimensional lattice, the continuous and omnidirectional movement of the plasmodium was limited to the stepwise one, and the direction of the locomotion was also limited to four neighbours. In such an experimental system, a cellular automata-like system was constructed using the living cell. We further analysed the exploratory behaviours of the plasmodium by duplicating the experimental results in the simulation models of cellular automata. As a result, it was revealed that the behaviours of the plasmodium are not reproduced by only local state transition rules; and for the reproduction, a kind of historical rule setting is needed. 相似文献
99.
Two‐way multi‐view 2‐D/3‐D display combining LC lens and HVxDP panel using novel pixel arrangement 下载免费PDF全文
Jin Matsushima Yukie Ibata Kazunori Masumura Takuya Asai Tetsushi Sato Koji Shigemura 《Journal of the Society for Information Display》2016,24(4):252-261
We have developed a two‐way multi‐view 2‐D/3‐D display combining a liquid crystal lens and horizontally and vertically x times‐density pixels (HVxDP) arrangement. The two‐way multi‐view display features the same display resolution in 2‐D and 3‐D modes and a quite small color moiré for landscape and portrait, respectively, when using the HVxDP arrangement. In this paper, we realized suitable 3‐D properties for achieving a good balance between 3‐D moiré and 3‐D crosstalk for landscape and portrait by a two‐way liquid crystal lens with two kinds of focal lengths for the edge part and the center part of the lens. 相似文献
100.
Hiroyuki Sato 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(10):3803-3820
MOEA/D is one of the promising evolutionary algorithms for multi- and many-objective optimization. To improve the search performance of MOEA/D, this work focuses on the solution update method in the conventional MOEA/D and proposes its alternative, the chain-reaction solution update. The proposed method is designed to maintain and improve the variable (genetic) diversity in the population by avoiding duplication of solutions in the population. In addition, the proposed method determines the order of existing solutions to be updated depending on the location of each offspring in the objective space. Furthermore, when an existing solution in the population is replaced by a new offspring, the proposed method tries to reutilize the existing solution for other search directions by recursively performing the proposed chain-reaction update procedure. This work uses discrete knapsack and continuous WFG4 problems with 2–8 objectives. Experimental results using knapsack problems show the proposed chain-reaction update contributes to improving the search performance of MOEA/D by enhancing the diversity of solutions in the objective space. In addition, experimental results using WFG4 problems show that the search performance of MOEA/D can be further improved using the proposed method. 相似文献