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Microplasma can be found in many applications. The technology is also used for surface treatment of polymers. The process of surface treatment by microplasma is environmental friendly, and it could be realized at low cost due to the relatively low discharge voltage (around 1 kV) even under atmospheric pressure and the small size of the power supply and reactor. This paper presents the surface treatment by microplasma of polyethylene naphthalate (PEN) film using Ar gas and mixtures of Ar with N2 and O2. The microplasma process was analyzed by the emission spectroscopy method. An experimental Marx generator with MOSFET switches was used as a pulsed high-voltage power supply. The emission spectra were measured by an intensified charge coupled device camera, a spectrometer, and a photomultiplier tube. Surface wettability of the PEN film was confirmed by measuring the contact angle before and after the microplasma surface treatment. It was observed that the contact angle of the PEN film decreased, especially with the O2/Ar mixture. The analysis using an X-ray photoelectron spectrometer showed the decrease of C1s, which correspond to the C-H bond. The emission spectrum of the microplasma discharge in the N2/Ar mixture showed Ar peaks, OH peaks, N2 second positive band system peaks (N2 SPS), N2 first positive band system peaks ( N2 FPS), and decrease in the peak intensities of ArI and OH for microplasma discharge in the O2/Ar mixture. The lifetime emission signals for the N2 SPS for the microplasma discharge in 0.25% N2 in Ar were around 1 μs. The calculation of the microplasma rotational and electron temperatures shows low rotational and high electron temperatures.

A Marx generator using MOSFET switches was built and studied in this paper for water purification. In order to replace the spark gap type of pulse power sources, with miss fire problems and short mechanical lifetime. In case of Marx Generator which generates negative pulses, a maximum output voltage of 3.6 kV, rise time of 40 ns and pulse width of 600 ns, was obtained. Discharge energy of one pulse was about 801 μJ for negative polarity at -2.4 kV. In case of positive pulses, a maximum output voltage of 3.6 kV, rise time of 75 ns and pulse width of 750 ns, was obtained. Discharge energy of one pulse was about 1120 μJ at 2.4 kV. The discharge was generated in bubbling water using a Marx Generator with MOSFET switches. The discoloration of indigo carmine solution was carried out to investigate the feasibility of low voltage discharge in bubbling water. As a result, indigo carmine solution was decolorized, although the discharge voltage was about -2.4 kV. The treatment performance was improved when oxygen was fed in the solution. The discoloration rate was 100 % after treatment time of 15 min with oxygen used as carrier gas. Emission of OH was confirmed and considered to play a role for water purification.

Microplasma technology was used in the last years for various applications such as NOx removal, sterilization of bacteria or surface treatment. The advantages of microplasma consist in reduced size of the reactor and low discharge voltage. Phenomena of microplasma could be analyzed using emission spectroscopy method. Our microplasma is atmospheric pressure nonthermal plasma. It is a dielectric barrier discharge generated between perforated metallic electrodes covered by a dielectric layer at small discharge gaps between 0 -100 μm. Thus the discharge voltage is around 1 kV Nitrogen, oxygen and argon were used as discharge gases. The emission spectra were measured by an ICCD camera, a spectrometer and a photomultiplier tube. Microplasma was pulsed powered by a Marx Generator and a high voltage amplifier.

Since 1997, we, the community pharmacists, have established this society, Aichi Prefecture Society for the Study of Pressure Ulcers Care, in order to furnish drug information about pressure ulcers care. Moist atmosphere is required for the healing of pressure ulcers. The moist environment that could be regulated depends on the physicochemical property of ointment bases. Therefore, ointment should reasonably be chosen to adjust the moisture. Since 2000, we have been committed to providing pharmacists, who work on home care, with a booklet to instruct how to choose ointments for pressure ulcers treatment. In 2002, when the Aichi pharmaceutical association held a training conference held at various hospitals using the booklet as a teaching material, hospital pharmacists cooperated by making a field study trip to observe pressure ulcers treatments. Nowadays researchers at pharmaceutical colleges have also cooperated in studying the efficacy and economical effect of the method of blending different ointments to improve the healing process of pressure ulcers.

As for pressure ulcers care, prevention is the most important approach. However, pressure ulcers, might develop despite enough care, depending on each person's physical condition. As for the treatment of pressure ulcers, maintenance of a moderately moist environment (60-70%) is quite important. We propose the use of ointment to control the moisture of a pressure ulcer environment. One ointment base absorbs moisture, while another provides moisture. We have prepared a manual that allows the user to select the medicine according to the degree of moisture of the affected part. When the moisture cannot be regulated with one ointment, it can be adjusted by mixing two or more ointments. In choosing a drug for external use, it is important to pay attention not only to the effect of the main ingredient but also to the physicochemical properties of the ointment base that serves as vehicle for that active component.

The steel for ice breaking vessels is required to have an excellent notch toughness at low temperatures and a good weldability and to meet the strict requirements in terms of workability and cost.The first report discussed the base-metal properties and joint performance of the 40 mm thick steel plate newly developed for ice breaking vessels.The present report discusses 75 mm thick steel plate also newly developed for the bow part, which has to meet severer requirements. The developed material is the 50 kgf/mm2 high tensile strength steel of 36 kgf/mm2 yield point manufactured by the CLC process. The test results showed that this new heavy plate has good mechanical properties, weldability and workability. It was also indicated that an ice breaking vessel to be made of this steel would be sufficiently safe against brittel fracture.

Recently, it has been very active to develop various types of marine structure and ice breaking vessels in order to exploit energy resources in ice fields. These steel structures are to be operated in severe environments of low temperature in the arctic area. Expecially, ice breaking vessels are required to navigate smoothly with breaking ice floe, thus the side shell and the deck structure should be fabricated of heavy plating with a good notch toughness.To obtain excellent notch toughness and mechanical properties, the authors introduced the new steel manufacturing process, namely CLC process and have successfully developed 50 kgf/mm2 class high tensile strength steel of heavy thickness.Then, experiments associated with fabrication, welding procedure and joint performance were carried out for this newly developed heavy section steel to study its applicability to hull structures of ice breaking vessel. It was consequently made clear that this steel could be welded by conventional welding procedure and showed a satisfactory performance which could assure the safety to be required for ice breaking vessel.