This paper represents a design for a hybrid rectangular and circular waveguide resonator. The resonator is designed specifically for the purpose of granular dielectric measurements, which resonates at 2.45GHz. The electric field distributions of the proposed resonator will be compared against ordinary resonators, and illustrated using a 3D computer simulation of isosurfaces and their contours and 3D projections. In this simulation the properties of samples (paddies and soils) are loaded into each design, in order to observe the electrical field distributions of each sample. Next, the probability density functions (PDF) and cumulative distribution functions (CDF) shall be used to determine the probability of electric field distributions within each type of resonator. Each designed resonator was created in order to process real experiment circumstances. The experiments for each resonator were processed using 20 paddy samples and 20 soil samples, in order to replicate real circumstances in an efficient manner. The percentages of moisture content (%MC) from each design were compared against %MC obtained using dry weight methodology, used to find errors. From the results, mean square error (MSE) shows that the hybrid resonator can improve output greater than the ordinary resonators, which are the rectangular resonator and circular resonator, with 78.738% and 63.213% respectively for paddy sample, and 70.605% and 46.520% respectively for soil sample, respectively. This demonstrates that the proposed resonator creates better results than the ordinary resonators, although the sample is changed.

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The surface roughness of sandpaper specimens with alumina abrasive was measured based on the effective reflectivity of terahertz waves. Measurement results based on the frequency dependence of the effective reflectivity were in agreement with measurement results using a contact surface roughness gauge to within 10% for surface roughness 10-35 µm. In addition, the frequency-averaged effective reflectivity was calculated with the surface roughness as a parameter. This provided a calibration curve to convert the measured frequency-averaged effective reflectivity to surface roughness. Measurement results based on the frequency-averaged effective reflectivity were in agreement with measurement results using a contact surface roughness gauge for surface roughness below 25 µm. The effect of the paint layer coating the abrasive did not result in significant error. The results showed that terahertz waves can be used for noncontact measurement of the surface roughness of dielectric surfaces.

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This paper demonstrates the electric power generator with both zero energy input and zero matter input and emission without violating the laws of thermodynamics. The hydrogen redox power generation system is a combined energy cycle consisting of the H₂O reduction by the electrostatic induction hydrogen electrolytic cell for the synthesis of pure stoichiometric H₂-O₂ fuel and the H₂ oxidation to H₂O by the fuel cell. The electrostatic induction potential superposed hydrogen electrolytic cell works on the mechanism in which, on the theoretical base, power used is 17% of the total electrical energy required, while the remaining 83% can be provided by the electrostatic energy free of power. Part of the power delivered by the fuel cell is returned to the electrolytic cell, and the remainder represents the net power output. For high power applications, the cycle power efficiency defined as the ratio of net power output outside the generator to power delivered by the H₂-O₂ fuel cell is of primary interest. According to calculations using the operational data of alkaline water electrolysis in industries, the cycle power efficiencies exceed 70%.

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An effect of discharge plasma irradiation to the circulating water in hydroponic cultivation system on plant growth rate was evaluated using Brassica rapa var. perviridis as specimen. The discharge plasma produced acids in the solution, which acts as a fertilizer. The Brassica rapa var. perviridis were cultivated in period of 42 days with the hydroponic system. The experimental result indicated that the growth rate of the Brassica rapa var. perviridis is improved drastically with the discharge treatment of the solution of hydroponic system, especially nitrogen content of leaf blade is significantly increased (P < 0.01).

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This paper presents an experimental study on decomposition of toluene gas in humid air using repetitive surface discharges on a dielectric barrier. Three kinds of voltages, polarity-reversed pulse with 50 ns of rise time, ac square with 0.1 ms of rise time and ac 50 Hz sinusoidal, are applied to a plasma reactor with a glass barrier between wire-plane electrode system. Experiments are done in two cases. In the first experiment, surface discharge light is observed by a still camera. Results of the photographic observation indicate that the light intensity for the polarity-reversed pulse voltage is much higher than those for the ac voltages not only under the dry condition but also under the humid conditions. It is remarked that no discharge light is observed for the ac sinusoidal voltage under the humid condition above 50 %R.H.. In the second experiment, toluene removal ratio and energy efficiency of toluene decomposition for a humid air including with 300 ppm gas-phased toluene are measured. Under a dry condition, there are no remarkable differences of the energy efficiency for toluene decomposition between the voltage waveforms. Under humid conditions, however, the energy efficiency for the ac voltages becomes lower than that for the polarity-reversed pulse voltage. The relationships between the toluene removal ratio and the consumed power can be simulated by an exponential function including geometry factor γ and discharge inception power P₀. We conclude that the surface discharge treatment by the very-fast polarity-reversed pulse is an effective way for toluene decomposition under humid conditions.

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VO_x precursor thin films were fabricated by metal-organic decomposition (MOD). Then, the films were fired with a temperature of 500-720°C, time of 5-20 min and pressure of 1.2-10 Pa in O₂ and the air (O₂: 21%). The composition of VO_x thin films, after the precursor films were fired at 650°C for 10 min, changed as V₂O₅ → V₃O₇ → V₆O₁₃ → VO₂ with decreasing the firing pressure in O₂. A phase transition (metal-insulator transition: MIT) was observed for the VO_x thin film containing VO₂ in R-T characteristic. However, the electrical properties were poor. On the other hand, VO_x thin film after the precursor films were fired at 650°C for 10 min under the pressure of 1.2 Pa in the air exhibited an abrupt transition, with a resistance change of 3 orders of magnitude, and a temperature coefficient of resistance (TCR) was 4.6 %/K. Furthermore, the VO_x film also exhibited an electrically triggered MIT in I-V characteristic and a switching operation with a threshold voltage of ∼6.0 V. These characteristics obtained by the VO_x thin film are applicable to bolometer detectors and switch devices.

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In general, a polymer insulator applied high voltage reaches a complete breakdown through a extension of electrical trees. We showed in previous paper that metal hydroxide has a restraint effect on the growth of an electrical tree and that the lifetime of the polymer insulator can be improve. Calcium carbonate, endothermic particle, also has the property of endothermic reaction at a high temperature. Therefore, we have studied the restraint effects of the endothermic filler without hydroxyl group on treeing this time. As a result, it was confirmed that the voltage lifetime of epoxy resin with 30 phr of calcium carbonate was approximately 100 times longer than that of the neat epoxy resin. Moreover, amorphous part of calcium carbonate was detected by the electron beam diffraction analysis of the fillers located contiguous to electrical tree, and it showed that endothermic reaction of calcium carbonate was took place. The restraint effect of the tree growth by fillers was generally explained by a barrier effect, but the endothermic fillers such as calcium carbonate that generated the endothermic reaction have another mechanism for restraint of tree growth.

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Ozone zero phenomenon (OZP) is caused by the decomposition of ozone which is composed in the ozone generator. In this letter, we report temporal variations of ozone concentration in ozonated gas during flow out from in a stainless steel pipe maintained at constant temperature of 200°C. The results show the temporal decrease of ozone concentration was observed by thermal decomposition at the surface of stainless steel and in the gas phase. On the contrast, the recovery of ozone concentration in the pipe is also observed after the great reduction of ozone concentration. These characteristics are similar to that of OZP.

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We demonstareted for the first time formation of plasmoid: O-point with closed flux inside the low-S (Lundquist number) current sheet by applying hollow equilibrium magnetic field. The plasmoid was found to stay around the minimum equilibrium field area with minimum J × B force of the equilibrium field. All direct measurements of plasma poitential, electron density and electron temperature have their peaks inside the plasmoid.

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