There are few published papers on whole-body average specific absorption rates (WBA-SARs) in humans for multiple radio-frequency (RF) simultaneous exposures. In this paper, to evaluate human safety of radio waves in real environments, we calculated WBA-SARs in pregnant woman and 3-years child models for multiple RF exposure, using measured results on electric field intensities from multiple base station antennas installed for cellular phones with four different RF waves in an underground shopping area and with five RF waves in the neighborhood of an elementary school, respectively. These data were reported officially in 2008 by the Ministry of Internal Affairs and Communications. Statistical analyses show that the sum of squared ratio of the measured electric field to the corresponding Japanese guideline for the general public is smaller than one-hundredth and one-thousand at most in the underground shopping and elementary school areas, respectively. As a result, we found that WBA-SARs in the pregnant woman and 3-years child models calculated at each of frequencies for base station antennas in the both areas are significantly low compared to the ICNIRP basic restriction (0.08 W/kg) for the general public, and that the sum of the WBA-SARs never exceed one-hundredth of 0.08 W/kg for multiple RF simultaneous exposures.

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A hydrogen electrolyzer for decomposition of chemically stable compound H₂O is essentially an electronic device that uses manly electrostatic-to-chemical energy conversion to produce a stoichiometric H₂+1/2O₂ fuel. To achieve a breakthrough in the practical hydrogen electrolytic cell, we demonstrate the electrostatic induction potential superposed electrolyzer. This system works on the mechanism in which, on the theoretical base, power used is 20% of the total electrical energy required, while the remaining 80% can be provided by the electrostatic energy free of power. Because H₂O is placed in its decomposition state in the electrostatic field where no current flows, the decomposition voltage is identified as a barrier potential that electrolytic current must overcome by expending the major part of the total system power. The potential superposition method for supplying energy to the cell was found to avoid the barrier potential effect within the laws of thermodynamics. Combining a fuel cell for producing power from pure H₂ and O₂ of stoichiometric ratio with this type of hydrogen electrolytic cell in a closed energy cycle can achieve a highly positive H₂ balance.

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This study experimentally clarified that changing the size of a charged object affects the characteristics of the electrostatic discharge (ESD) that occurs when a charged object moves toward a stationary, grounded object. The spark lengths and discharge currents were measured as charged, metallic, spherical electrodes of different diameters approached a stationary grounded object at different speeds. The charge voltages of a DC high-voltage power supply were +4.0kV and +6.5kV. According to the results, the average spark length tended to shorten with the speed of the spherical electrodes. The change in the average spark length with the speed of the 5.0-mm-diameter spherical electrode was faster than that for the 15.9mm-diameter spherical electrode. The average peak value of the first peak of the discharge current for the 5.0-mm-diameter spherical electrode was greater than the average value for the 15.9-mm-diameter spherical electrode when the approach speed was greater than 5mm/s for both spherical electrodes. The peak value, rise time, and rising speed of the first peak of the discharge current also correlate with the spark length, and the correlation can be explained qualitatively by the empirical equation deduced from the resistance formula proposed by Rompe and Weizel .

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Purpose of this paper is to investigate the impact of changes of moisture content and growth of fungi on the electrical impedance characteristics of brown rice. Brown rice was stored in the constant temperature and humidity chamber (30°C, 90% RH) in order to change the moisture content of brown rice. During the storage, the electrical impedance of the sample was monitored by using insertion type electrodes. As a result, the electrical impedance characteristics of brown rice were modeled by the parallel circuit model composed of resistance and constant phase element (CPE). Focusing on the relationship between moisture content and model parameters, resistive component R decreased and capacitive component C increased with increasing moisture content. Especially R has a strong exponential correlation with the moisture content. The moldy brown rice was prepared by 40 days storage under the condition of 30°C, 90% RH. As is the case with the ordinary brown rice, R decreased and C increased at higher moisture content. However, variations of these parameters with respect to the moisture content were quite small compared to the ordinary brown rice. It was considered that the changes of electrical characteristics were due to the shedding of the aleurone layer caused by the growth of fungal filament and changes in composition of brown rice by metabolism of fungi. These findings obtained from above results would be useful in evaluating the quality of brown rice.

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Pulsed electric discharge in water has been intensively studied recently for industrial, environmental and biomedical applications as a prolific source of different active species and reactive radicals. The main purpose of this work is to investigate effects of three parameters- such as gap distance, electrode configuration and pulse repetition rate on hydrogen peroxide generation using pulsed discharge in bubbling water. A ceramic filter is employed to isolate both gas and liquid phases and generate bubbles by feeding argon gas through the filter. The experimental results are as follows: the concentration of H₂O₂ increases significantly with a shortened gap distance, and discharge characteristics change from streamer-like to arc-like discharges depending on the propagation of streamer through bubbles to the ground electrode. An increased yield of H₂O₂ was also found with treatment time, pulse repetition rate and use of the needle-to-mesh electrode configuration.

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Carbon monoxide (CO) is an extremely harmful gaseous pollutant causing serious poisoning symptom. CO generation also creates various environmental pollution problems such as a photochemical oxidant, acid rain and the global warming. CO was generated from various sources such as power generation facilities, manufacturing factories, automobile vehicles as well as homes heating facilities by incomplete combustion. The aim of our research was focused on CO oxidation using the atmospheric barrier discharge plasma reactor. The influence of moisture content and oxygen concentration on CO oxidation was investigated. As a result, the CO conversion was improved with increasing moisture content due to oxidation reactive species such primarily OH radicals but was reduced with increasing oxygen concentration. This was attributed to the reduction of O radicals which reacts preferentially with OH radicals but not for CO oxidation for this experimental condition.

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Under non-uniform field in atmospheric short-gap, the branched pulse streamer corona changes to single liner discharge channel (SLDC) for a split second just before sparkover occurs. This SLDC is pre-transitional phenomenon of sparkover. Therefore, it is very important to study SLDC for understanding sparkover process. In this work, the SLDC was recreated well by applying highly repetitive impulse voltage to needle to plane gap in synthetic air with dilute CO₂. The characteristics of SLDC including the channel temperature, the propagation of streamer head and the formation process were revealed by means of ICCD cameras and a spectroscopic measurement system.

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It is well known that magnetic properties of electrical steel sheets are influenced due to mechanical stress strongly. We have been measured residual stress distribution with a X-ray stress measurement device and clarified not only the tensile and compressive stress but also the shear stress in a rotating machine core. In particular, the influence of the shear stress on the magnetic property has not been reported. We try to develop a new measurement system of vector magnetic property under the shear stress. This paper presents a mechanism to apply the shear stress and the measured vector magnetic property of a non-oriented electrical steel sheet under the shear stress. As these results, the difference of the vector magnetic property of the non-oriented electrical steel sheet was obtained according to the shear stress.

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Electric double-layer capacitors (EDLCs) have problems that the specific capacitance decreases by increasing scan rate. In this study, activated carbon (AC) and various carbon nanomaterials are compared by their specific capacitances. Carbon nanomaterials used were arc-black (AcB) which was prepared by an arc discharge and carbon nanocoil (CNC) which was prepared by a chemical vapor deposition. CNC and AcB showed lower charge transfer resistance than AC in the measurement of electrochemical impedance spectroscopy (EIS). This explains that the EDLCs composed of CNC and AcB kept their specific capacitance at a high scan rate.

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To achieve the aim of developing a new insulating substrate that can exhibit both high permittivity and high permeability, ferromagnetic iron nanoparticles were dispersed uniformly in epoxy resin. Measurements of the electrical conductivity, permittivity, and permeability indicate that the composite can be a good candidate for an insulating substrate with negligibly small eddy-current loss and sufficiently high permittivity.

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The principle of sound production in human whistling is not well-known. The purpose of this letter is reconsideration on the principle of sound production in human whistling using physical models of the human vocal tract based on the X-ray CT data. This letter shows that the whistling resonant frequency is very near the formant resonance frequency.

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