飯村 健次

The effect of terephthalic acid particle properties on particle fracture phenomena was investigated in this study. Furthermore, to evaluate the fracture characteristics in real process, the effect of the particle impact angle on particle fracture phenomena was also investigated. The results of this study indicated that: (i) the crystallite size correlated with the fracture stress of the particle; (ii) the crystallite size also showed a correlation with the critical fracture velocity and the kinetic energy of the particle; and (iii) the particle fractured more easily at impact angles under 45°.

A new method for determining the liquidus and solidus pressures of mixtures of C18's unsaturated fatty acids at constant temperatures was proposed, and three binary isothermal SLE data under high-pressure were systematically measured in this study. The liquidus and solidus temperatures of oleic acid, linoleic acid and alpha-linolenic acid commonly rise above their normal melting temperatures when pressure is increased. This new high-pressure experimental system can closely track pressure in real time during pressure swinging changes, making it simple to measure liquidus and solidus pressures using this dynamic measurement method due to fast responsiveness of pressure. In this study, the liquidus pressures of pure oleic acid, linoleic acid, alpha-linolenic acid and three binary mixtures consisted of oleic acid, linoleic acid alpha-linolenic acid at constant temperature were determined. The isothermal SLE were first correlated based on a simple thermodynamic model. (C) 2021 Elsevier Ltd.

In this study, a novel reversible control method of particle dispersion/flocculation for nonaqueous solvent was developed. Titanium oxide was used as sample powder. Cyclopentasiloxane was used as solvent and Polyoxyethylene polyalkylsiloxane was used as a dispersant. First, a well-dispersed slurry was prepared by adding dispersant. After preparation, alcoholic amphiphilic molecule was added to the well-dispersed slurry to convert it from liquid to a gel-like consistency, which was caused by the hydrogen bond of dispersant on the surface of the particles. The resultant gel could easily be changed to liquid state by shaking. In addition, the slurry reverted back to gel state after a certain period of time. It was found that the relative permittivity and the additive amount of amphiphilic molecule has an influence on the strength of the gel.

A nickel-metal hydride (Ni-MH) prototype battery completely immersed in an aqueous electrolyte solution of KOH under high-pressure was fabricated to examine the effects of high-pressure on the quality of Ni-MH batteries. The small battery cell comprised positive and negative electrode materials, as used in electric vehicles, and an Ag/AgO reference electrode. The electric capacity of the Ni-MH battery was measured at different temperatures and pressures with small currents and charge/discharge voltages of 1.6-1.0 V. High-pressure was found to clearly and effectively enhance the electric capacity of the Ni-MH battery at larger currents. The considerable effect of high-pressure on the Ni-MH battery was elucidated by the change in internal resistance during the charge/discharge cycle life experiment, indicating that the voltage of the positive electrode did not appreciably change under high-pressure compared to that of the negative electrode. Moreover, the use of large currents in rapid charge/discharge cycle tests at high pressures of up to 30 MPa resulted in charge/discharge cycles that were five times faster and a quick recovery of capacity was achieved in the 0.5-2.1 V range.

We fabricated a surface acoustic wave (SAW) actuator by patterning an interdigital transducer (IDT) made of Al film on a LiNbO3 substrate and investigated its transport characteristics with powders of spherical copper, spherical glass, spherical polyethylene, and angular alumina particles with sizes of about 100 μm. The IDT had a 2 mm pitch size, 10 mm aperture, and 10 stripline pairs. It was found that the glass, polyethylene, and alumina powders that could not be transported when the actuator was horizontal could be transported by tilting the actuator, i.e., the powder transport path. It was also found that the powder movement response times with SAWs were shorter than 50 ms when the actuator, tilted at suitable angles of 0°, 6°, 15°, and 26°, transported the copper, glass, polyethylene, and alumina powders, respectively. Then, we fabricated miniature feeders by mounting hoppers on SAW actuators tilted at the above angles and investigated their powder feed characteristics. It was found that, when the feeders were driven for 50 ms at an electric power of 1 W, the fed weights of the copper and glass powders, which did not have flowability problems, were 2.3 and 0.9 mg, respectively.