Multiferroic nanocomposite fabrication via liquid phase using anodic alumina template

We report a novel and inexpensive fabrication process of multiferroic nanocomposite via liquid phase using an anodic alumina template. The sol-gel spin-coating technique was used to coat the template with ferrimagnetic CoFe₂O₄. By dissolving the template with NaOH aqueous solution, a unique nanotube array structure of CoFe₂O₄ was obtained. The CoFe₂O₄ nanotube arrays were filled with, and sandwiched in, ferroelectric BaTiO₃ layers by a sol-gel spin-coating method to obtain the composite. Its multiferroicity was confirmed by measuring the magnetic and dielectric hysteresis loops.     

Relationship between Rice Flour Particle Sizes and Expansion Ratio of Pure Rice Bread

We examined a method to produce bread from crystalline rice flour without using thickening agents such as gluten, polysaccharide thickening, and amorphous rice flour. Rice grains were pulverized by a jet mill to produce flour. Samples of rice flours of various particle size distributions were prepared by using a size shifter. The degree of starch damage and the dynamic viscoelasticity of rice batter were measured in this work. We also baked bread of the flour of each size distribution to study processability for making bread. The batter made by the pulverized flour of rice particle size ranging from 75 to 106 μm had the highest expansion ratio and a good processability for baking breads compared to other particle size batters. The rice bread with high expansion ratio was produced by controlling particle size of crystalline rice flour without using thickening agents.     

Experimental Study of DBD Plasma Actuator with Combination of AC and Nanosecond Pulse Voltage

In the last decade, dielectric barrier discharge (DBD) plasma actuators using a combination voltage of AC and a nanosecond pulse have been studied. The combined‐voltage‐driven plasma actuator increases the body force effect, including wall jet and flow suction, by overlapping the nanosecond pulse voltage, while the DBD plasma actuator driven by nanosecond pulses is a flow control actuator generating compression waves due to pulse heating, which makes it possible to supply an active flow control at a high‐speed flow, reported as up to Mach 0.7. In this study, a DBD plasma actuator driven by a combination voltage of sinusoidal AC and nanosecond pulse was experimentally investigated. The time‐averaged net thrust and cycle‐averaged power consumption of the actuator were characterized by using an electrical weight balance and the charge‐voltage cycle of a DBD plasma actuator, respectively. The plasma actuator thrust driven with the combination voltage showed increased thrust with increasing pulse repetition rate. The energy consumption of the actuator was controlled by varying the AC phase when the nanosecond pulse was applied. Therefore, the thrust and power consumption in the actuator were almost independently controlled by the pulse repetition rate and the pulse imposed phase.     

Development and Application of Multiple‐Probe Scanning Probe Microscopes

In the research of advanced materials based on nanoscience and nanotechnology, it is often desirable to measure nanoscale local electrical conductivity at a designated position of a given sample. For this purpose, multiple‐probe scanning probe microscopes (MP‐SPMs), in which two, three or four scanning tunneling microscope (STM) or atomic force microscope (AFM) probes are operated independently, have been developed. Each probe in an MP‐SPM is used not only for observing high‐resolution STM or AFM images but also for forming an electrical contact enabling nanoscale local electrical conductivity measurement. The world's first double‐probe STM (DP‐STM) developed by the authors, which was subsequently modified to a triple‐probe STM (TP‐STM), has been used to measure the conductivities of one‐dimensional metal nanowires and carbon nanotubes and also two‐dimensional molecular films. A quadruple‐probe STM (QP‐STM) has also been developed and used to measure the conductivity of two‐dimensional molecular films without the ambiguity of contact resistance between the probe and sample. Moreover, a quadruple‐probe AFM (QP‐AFM) with four conductive tuning‐fork‐type self‐detection force sensing probes has been developed to measure the conductivity of a nanostructure on an insulating substrate. A general‐purpose computer software to control four probes at the same time has also been developed and used in the operation of the QP‐AFM. These developments and applications of MP‐SPMs are reviewed in this paper.     

Discovery of Superconductivity in 2M WS2 with Possible Topological Surface States

Recently the metastable 1T′‐type VIB‐group transition metal dichalcogenides (TMDs) have attracted extensive attention due to their rich and intriguing physical properties, including superconductivity, valleytronics physics, and topological physics. Here, a new layered WS₂ dubbed “2M” WS₂, is constructed from 1T′ WS₂ monolayers, is synthesized. Its phase is defined as 2M based on the number of layers in each unit cell and the subordinate crystallographic system. Intrinsic superconductivity is observed in 2M WS₂ with a transition temperature T_c of 8.8 K, which is the highest among TMDs not subject to any fine‐tuning process. Furthermore, the electronic structure of 2M WS₂ is found by Shubnikov–de Haas oscillations and first‐principles calculations to have a strong anisotropy. In addition, topological surface states with a single Dirac cone, protected by topological invariant Z₂, are predicted through first‐principles calculations. These findings reveal that the new 2M WS₂ might be an interesting topological superconductor candidate from the VIB‐group transition metal dichalcogenides.     

Elimination of glycidyl palmitate in diolein by treatment with activated bleaching earth

In this study, activated bleaching earth (ABE) was used to eliminate glycidyl esters from both triacyl- and diacylglycerol oils. To investigate the mechanism, glycerol dioleate containing glycidyl palmitate (GP) was treated with ABE and the fate of the GP was monitored by analyzing the feed, treated, and ABE-absorbed oils using a gas-liquid chromatograph equipped with a flame-ionized detector. GP was completely removed from both the treated and absorbed oils. This indicates that this treatment is useful for GE removal from diacylglycerol oil, although it was not achieved by absorption of GE on ABE but rather by modification of GP. The results of composition analysis demonstrate that GP is transformed to glycerol monopalmitate, glycerol palmitate oleate, and glycerol dipalmitate at a recovery rate of 99.1 ± 1.3 %. An increase in glycerol monooleate and trace amounts of free glycerol and fatty acids were also observed after treatment. The transformation is proposed to involve a ring-opening reaction of GP with water contained in the ABE and in the bulk oil followed by an interesterification reaction among the resultant monopalmitate and the glycerol dioleate of the bulk oil. All the generated compounds were simple acylglycerols and glycerol. Therefore, ABE treatment could be useful for GE removal during the manufacture of edible oils.     

Hydrocracking of diphenylmethane: Roles of H2S and pyrrhotite

To define the roles of H₂S and pyrrhotite in high temperatures employed for normal coal liquefaction, diphenylmethane hydrocracking with H₂ and H₂-H₂S was carried out with and without pyrrhotite. H₂S promotes diphenylmethane hydrocracking with H₂ both in the presence and absence of pyrrhotite, and the reaction is dependent upon the H₂S pressure in both instances. It is also dependent on the H₂ pressure when pyrrhotite is present. The results are interpreted in terms of H₂S acting as a hydrogen transfer catalyst.     

Evaluation of driver’s behavior with multibody-based driving simulator

This paper deals with a driving simulator with a multibody vehicle model. Driving simulators require a real-time calculation of vehicle dynamics in response to driver’s inputs, such as a steering maneuver or a brake pedal operation. The authors realized a real-time calculation with a multibody vehicle model by approximating the calculation of constraint equations, and developed a driving simulator with 6-axes motion system. Drivers can feel the multibody analysis results through body sensory information such as the acceleration produced by the motion system and the visual information generated by computer graphics with the developed MBS simulator system. In this paper, a closed-loop test of a human-automobile system was investigated with the developed MBS driving simulator. In this evaluation, the driving simulator system and driver’s behavior were included in a multibody dynamics analysis, so it consists of a hardware- and human-in-the-loop simulation. It was observed from test results that the driving behavior was changed according to the parameters of the multibody vehicle model.     

Combined carbon‐dioxide‐capturing high‐performance power generation system using a solid oxide fuel cell operating on pressurized fuel/air

The authors recently proposed a high‐performance combined carbon‐dioxide‐capturing power generation system using a solid oxide fuel cell (SOFC) and a closed‐cycle MHD generator, in which pure oxygen is used as the oxidant. This combined system makes the best use of the advantages of combustion with pure oxygen but fails to prevent the efficiency deterioration caused by high power demand for oxygen production. In the present study, the authors modified this previous system and proposed an improved combined carbon‐dioxide‐capturing power generation system using SOFC/MHD characterized by a higher overall thermal efficiency. In this system, pure oxygen is supplied only to the combustor to reduce the power required for the oxygen production, and pressurized air is used as the oxidant gas in the SOFC. The power saving amounts to about 5% of the thermal input, resulting in a very high total thermal efficiency of 67.53% (HHV) or 74.94% (LHV), which is considered to be the highest possible value of the overall thermal efficiency of carbon‐dioxide‐capturing systems. Advantages of the proposed system suggest that it is advisable to continue further research in this direction. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 149(4): 21–30, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20010