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An atmospheric pressure glow discharge was generated using a needle-array electrode in nitrogen, and the voltage–current characteristics of the glow discharge were obtained in a range from 1 mA to 60 A. A pulsed high voltage with short rise time under 10 ns was employed to generate streamer discharges simultaneously at all needle tips. The large number of streamer discharges prevented the glow-to-arc transition caused by inhomogeneous thermalization. Semiconductor opening switch diodes were employed as an opening switch to shorten the rise time. The glow voltage was almost constant until the discharge current became 0.3 A, whereas the voltage increased with the current higher than 0.3 A. Electron density and temperature in a positive column of the glow discharge at 60 A were obtained to 1.4×1012cm−3 and 1.3 eV from calculation based on nitrogen swarm data.

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The mechanism of the chiral symmetry breaking is investigated in the strong-coupling Abelian gauge theories at finite temperature. The Schwinger-Dyson equation in Landau gauge is employed in the real time formalism and is solved numerically within the framework of the instantaneous exchange approximation including the effect of the hard thermal loop for the photon propagator. It is found that the chiral symmetry is broken below the critical temperature T for sufficiently large coupling α. The chiral phase transition is found to be of the 2nd order and the phase diagram on the T − α plane is obtained. It is investigated how the structure of the chiral phase transition is affected by the hard thermal loops in the photon propagator.

A pulsed high voltage was applied to logs for mushroom cultivation to investigate an effect of pulse high voltage on mushroom growth. Inductive energy storage system was utilized to construct a pulsed power generator with compact size. Copper fuse of 0.03 mm diameter was used as an opening switch to interrupt large circuit current in short time. The voltage charged in primary energy storage capacitor was multiplied using secondary energy storage inductor. The output voltage of the pulsed power generator was 120 kV with 100 ns pulse width at 14 kV charging voltage of 0.22 µF primary energy storage capacitor and 15 µH secondary energy storage inductor. This pulsed high voltage was applied to 90 cm length logs inoculated Pholiota nameko fungus. The yield of Pholiota nameko mushrooms was successfully improved with the pulse voltage stimulation. The total weight of the cropped Pholiota nameko after the pulse voltage stimulation was 6.3 kg for fifteen logs and this value was 1.5 times larger than 4.3 kg of total weight without the stimulation. The number of logs with lower than 0.27 kg cropped Pholiota nameko weight which was an average value for control group was only one in fifteen, whereas four logs in control group showed almost zero weight of cropped Pholiota nameko.