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To investigate the three-dimensional (3D) structure of nanoparticle (NP) aggregates in rubber tire treads with a large system size, a particle-mesh-based two-dimensional (2D) pattern reverse Monte Carlo (PM-2DpRMC) method was applied to a series of 2D scattering patterns (2DSPs) of NPs during stretching and unloading. To characterize the structures of aggregated NPs, a high-connectivity cluster analysis based on the number of NPs within a specific cutoff distance was introduced. Similar to the reverse Monte Carlo (RMC) analysis of a one-dimensional scattering spectrum, PM-2DpRMC analysis for the case before stretching clarified that the characteristic cluster sizes of silica NPs in end-modified styrene–butadiene rubber (M-SBR) treads were smaller than those in nonmodified SBR (n-SBR) treads. Changes in the 3D configurations of NPs during stretching were modeled from a series of 2DSPs of NPs by repeating the stepwise deformation of the box of the periodic boundary condition, and this method was termed the “on-the-fly PM-2DpRMC” method. The high-connectivity cluster analysis elucidated that the NPs in the M-SBR treads aggregated more at higher elongation ratios (ε); however, the characteristic sizes of the NP aggregates in the n-SBR treads were slightly small at higher ε values. At a high ε of >140%, although the number of clusters in the M-SBR treads became close to those in the n-SBR treads, the difference between the characteristic sizes of NP aggregates was retained. Furthermore, the high-connectivity cluster analysis was mathematically more sensitive for the characterization of NP morphologies than a previously reported analysis based on the Voronoi cell volume. The high-connectivity cluster analysis helps clarify the justification of the on-the-fly PM-2DpRMC method and its numerical comparison with the PM-2DpRMC analysis starting from random NP configurations. Moreover, the results of this study elucidate the importance of a lower scattering wavenumber, q, limit in the modeling of NP aggregation.

A floating signage which means optical images are floating in the air is one of the useful ways to attract people's attention. Since 2019, our research group proposed unidirectional observable aerial signage display using thin film layers or dye-dopedoptical prisms to avoid mirrored imaging problem which means observers end up watching wrong messages or images from back side. In this paper, the authors describe the aero signage using quasi-spatial floating image and how to generate floating images using optical illusion and to control light paths.

Hardwood lignin in eucalyptus was first converted to hardwood lignocresol through a phase separation process utilizing wood meal, sulfuric acid, and p-cresol at ambient temperature. A syringyl methyl benzofuran, S2 was selectively obtained via a syringyl-type phenolic dimer with a coumaran ring, S1 by NaOH treatments of hardwood lignocresol at 170?°C. Our process controls the reactivity of Calinkages, Cß-aryl-ethers, and C?-OH in sequence, successfully resulting in a high yield of specific aromatic chemicals from hardwood lignin based on the successiveness of Cß-aryl-ethers between syringyl units.

A composite structure of piezoelectric particles and soft polymer composite material is one of the candidates that converts environmental vibration energy into electrical energy. Presently, expanding the usage of applications is needed in terms of the working environment at harsh temperatures. Polyimide is flexible and temperature-stable polymer. In this research, we report a synthesis of polyimide/(Na,K)NbO3(PI/NKN) flexible composites. We constructed a setup, where vibration and heat are simultaneously applied to the PI/NKN composites. The frequency and temperature dependence of the output voltage were investigated at room temperature up to 200 °C. Relative permittivity, piezoelectric constant, and output voltage of the PI/NKN showed temperature stability. Flexibility and glass transition temperature of a polymer matrix are important factors. PI/NKN composites are potential energy harvesting materials with flexibility and excellent high-temperature stability.

This paper describes the generation of periodic motions of solid particle in an oil phase under a direct current (DC) voltage. We found that a dimer and trimer composed of spherical polystyrene (PS) particles exhibit a novel periodic motion, spin. These particles maintain their stable motion without any support from mechanical devices such as rotational axes or electronic switching devices. We expect that the simple DC micromotion is applicable for mechanical and fluidic devices employing microrobots and microfluidics.This paper describes the operation of a solid particle of submillimeter size under a stationary direct current (DC) voltage. We show that, in an oil phase containing an ionic surfactant, solid particles exhibit periodic motions, such as revolution and spin, depending on their morphology. We also found that the speed can be controlled by tuning applied voltage.

Ion-selective Marangoni instability (MI) was studied by electrochemical measurements in order to determine the non-hydrodynamic nonlinear dynamics inherent to the process. An oil-soluble surfactant and calcium ion reacted at the interface, where the reaction products form aggregates. We generated a macroscopic interface where interfacial processes such as reaction and aggregation were synchronized. In this case, a non-hydrodynamic regime was observed before convection: Immediately after applying voltage, we observed an unsynchronized interface and an irregular interfacial flow. However, when the amount of ion transport across the interface exceeded a threshold value, the interface became synchronized, and successive occurrence of MI appeared as a periodical oscillation of interfacial tension. An aggregate of reaction products was considered to proceed homogeneously over the whole synchronized interface. We used a hemispherical droplet shape, and thus an increase in interfacial tension decreased the interfacial area. The interface was then compressed, providing a mechanical work for the desorption of aggregated products. This triggered a hydrodynamic instability.

Interactive Evolutionary Computation (IEC) is known as an effective method to create media contents suited to user’s preference and objectives. As one of the methods, we have applied Differential Evolution (DE) as evolutionary algorithm in IEC. This study investigated the efficacy of Interactive Differential Evolution (IDE) in comparison with Interactive Genetic Algorithm (IGA). Two listening experiments were conducted to investigate the efficacy: experiment 1 as a creating experiment with IDE and IGA, experiment 2 as a re-evaluating experiment. Target of the creation was warning sign sounds. Eighteen subjects participated in both of the experiments. The result of the experiment 1 showed that IDE overcame IGA, and significant increase of fitness was only observed in IDE. The result of the experiment 2, higher fitness value was observed in IDE, however, the difference between the two conditions was not significant. Parts of the results showed a possibility of IDE to create media contents.