To realize wireless power transfer with high energy density, cyclotron wave converter (CWC) capable of high-power output was aimed to be used as a millimeter-wave rectifier. There have been no studies on the design of the CWC at higher frequencies, and the issue is whether each component of the CWC can operate in the millimeter-wave band. In this paper, the technical feasibility of the external magnetic field and a main body at millimeter-wave was discussed from a technical point of view. Finally, the cavity efficiency reduction of the CWC is limited to 5 %, compared to a controllable center frequency of 0.02 % on the oscillator side in the millimeter-wave band. Although resonance with the oscillator becomes difficult at frequencies above the millimeter-wave band, it was found that high-efficiency operation is possible up to the millimeter-wave band.

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In this study, to improve the thrust performance of a small-sized low-power anode-layer Hall thruster, an experimental investigation was performed for a newly developed thruster. In addition, particle simulation employing the radial-axial 2D3V Full-PIC-MCC method was conducted to optimize the operational conditions. From the results, it was shown that measured thrusts and specific impulses were 0.2 0.6 mN and 110 310 s, respectively, for discharge power of 11 130 W with Xe propellant of 0.2 mg/s. On the other hand, from the particle simulation, calculated thrusts and specific impulses were 0.78 1.3 mN and 400 710 s, respectively, for discharge power of 20 50 W with Xe, showing potentials of the improvement and optimization of the anode and magnetic field geometries to achieve much higher thrust performance.

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Characterization of temporal and spatial ion velocity distributions for a newly developed coaxial laser-assisted pulsed plasma thruster (LA-PPT) was conducted with a retarding potential analyzer (RPA). From the measurement, it was shown that the most probable velocities exhausted from the LA-PPT increased from 32 km/s to 47 km/s, and from 35 km/s to 51 km/s, for laser energies of 100 mJ and 150 mJ, respectively, with increase of charged voltages of capacitors from 0 V to 5 kV. In addition, It was shown that with a pulse discharge condition, a relatively flat part of ion beam distribution at the central region was observed roughly corresponding to a diameter of the thruster exit (30 mm), showing that ions emitted from the thruster were exhausted as a relatively straight beam without significantly diverging.

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Pt nanoparticles were synthesized by a cavitation bubble plasma (CBP) with a pair of Pt rod electrodes. Pt nanoparticles were loaded on TiO2 particles to produce Pt/TiO2 photocatalysts. Regardless of the processing time during nanoparticle synthesis, the Pt nanoparticles were spherical shape of diameter about 1.5 to 3.0 nm. Pt nanoparticles supported on TiO2 particles increased in particle size due to agglomeration with increasing processing time. The hydrogen production amount by the photocatalytic reaction of Pt/TiO2 in glycerol solution increased with increasing CBP processing time, reaching 71.1 μmol/h at 5 minutes of processing time.

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Atmospheric pressure microplasmas were applied to synthesize hydrogenated diam ond like carbon films on a silicon substrate using a gas mixture of CH 4 /He/H 2 . The film deposition was carried out by moving a substrate. For the films synthesized by a CH 4 /He plasma, the surface hardness increased from 7.7 GPa to 10 3 GPa with increasing substrate temperature from 100 to 300 due to dehydrogenation. Furthermore, the surface hardness increased from 10 GPa to 18 GPa with H 2 addition of 10% to a CH 4 /He plasma at substrate temperature of 300 ℃℃. The sp 3 /(sp 3 +sp 2 and (sp 3 CH+ sp 3 CH 2 sp 3 CH+ sp 3 CH 2 +sp 3 CH 3 ratios of the films increased from 48.5 to 52.6% and from 53.7 to 7 3 5 with H 2 addition of 10%, respectively. A nd typical deposition rate of 1.8 μm/s w a s attained at a condition of H 2 addition of 10% and substrate temperature of 300

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