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Ball-milling and subsequent microwave heating processes have been applied to synthesize VBO 3 –C composite. The samples were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, inductively coupled plasma mass spectroscopy, and electrochemical methods. The VBO 3 –C composite was successfully prepared after 30 min ball-milling and 13 min microwave heating. The synthesized VBO 3 –C composite was composed of well crystallized VBO 3 particles with well dispersed amorphous carbon and exhibited higher reversible capacity (625 mAh g −1 ) and improved cyclic performance than those in previous study.

Atmospheric pressure radio frequency (rf) glow discharge characteristics were studied aiming for the plasma treatment of living tissues such as pork and human skin. Electrical and optical measurements of the plasma gave reasonable values at low current of 4 mA and gas temperature of 60 °C at 100 W. The colorimetric measurement of the treated pork sample demonstrated negligible thermal effect from the plasma. In addition, the sterilization efficiency of Escherichia coli inoculated on pork surface was comparable with that of a conventional UV sterilizer. The experimental results promise that the atmospheric pressure rf plasma can be safely applied to human skin treatment without electrical and thermal damage.

Bio-applications of plasma have been widely studied in recent years. However, considering the high interests, the inactivation mechanisms of micro-organisms by plasma have not been clearly explained. The goal of this study was to find the sterilization mechanisms and define the major sterilization factors with the atmospheric pressure radio-frequency helium glow discharge. For the sterilization target the Escherichia coli was used. To begin with the sterilization study, the plasma characteristics were investigated by means of electrical and optical diagnostics. Especially, the gas temperature was controlled under 50 C by keeping the input power less than 70 W to eliminate the thermal effects. Contribution of the UV irradiation from the plasma was studied and it turned out to be negligible. On the other hand, it was found that the sterilization was more effective up to 40% with only 0.15% oxygen addition to the helium supply gas. It indicates that the inactivation process was dominantly controlled by oxygen radicals, rather than heat or UV photons.

A few millimeter size plasma was generated in a pin to plane electrode configuration with either Aluminum or Indium Tin Oxide glass. Depending on the plane electrode material, the plasma showed either corona or corona-dielectric barrier discharge hybrid discharge characteristics. From electrical and optical diagnostics, it was found that the hybrid discharge was more electrically stable and had lower rotational temperature. A feasibility study of material surface modification was performed with the hybrid discharge. All samples such as polyethylene and polypropylene films became more hydrophilic, and the surface property was changed only within the radius of less than about 12 mm. In addition, several effects of gas temperature and treatment time on the surface modification were studied besides the durability.

A very simple and rapid method for synthesizing LiFePO 4 -C composite has been developed by vibrant type ball-milling for 30 min and microwave heating for 2–4 min. X-ray diffraction and Mossbauer spectroscopy verify that well-crystallized LiFePO 4 without Fe 3+ impurities is obtained. From laser particle size analysis and transmission electron microscopy, it is confirmed that a LiFePO 4 -C composite with fine and uniform particle size (mean particle size ≤0.640 μm, D75 in volume distribution ≤0.592 μm) and with extremely uniform carbon distribution is prepared by vibrant type ball-milling and microwave heating. The LiFePO 4 -C delivers a high initial discharge capacity of 161 mAh g −1 at C/10 and shows very stable cycling behaviour.

The structure of passive film formed on Ti in pH 8.5 buffer solution was examined by comparing the photocurrent for both the passive film and the thermally grown oxide on Ti in air at 400 °C. The passive films formed on Ti in pH 8.5 buffer solution showed optical band gap energy of 3.36 eV, while the thermally grown oxide film on Ti was found to have band gap energy of 3.1 eV. The higher value of band gap energy of passive film was attributed to the less crystalline or more disordered structure of passive film compared to that of the thermal oxide. This fact was supported by the higher disorder energy of passive film, determined from the absorption tail of photocurrent spectrum, than that of thermal oxide.

The CN (BΣ+2-XΣ+2) molecular emission spectrum is used to measure both the vibrational and rotational temperatures in atmospheric pressure arc jet discharges. The vibrational and rotational temperature effects on the synthetic diatomic molecular spectra were investigated from the (v′,v″)=(0,0) band to the (5,5) band. The temperatures obtained from the synthetic spectra compared with the experimental result of a low-frequency arc discharge show a vibrational temperature of (4250–5010)K and a rotational temperature of (3760–3980)K for the input power in the range of (80–280)W. As the (0,0) band is isolated from other vibrational transition bands, determination of the rotational temperature is possible based only on the (0,0) band, which simplifies the temperature measurement. From the result, it was found that the CN molecular spectrum can be used as a thermometer for atmospheric pressure plasmas containing carbon and nitrogen.

Repassivation kinetics of Ti in deaerated pH 8.5 buffer solution were investigated using a rapid scratching electrode technique. The repassivation kinetics were analyzed in terms of the current density (i) flowing from the scratch as a function of the time (i). The rate of repassivation was evaluated by the repassivation time (t r ) that has been passed to achieve the predetermined current density (i r ) from scratching, where the shorter t r the faster the repassivation rate. The repassivation rate increased as the applied potential and solution temperature increased, which was attributed to the corresponding increase in the rate of oxygen vacancy (V o ) generation reaction at the metal/passive film interface according to the point defect model. The increase in the rate of oxygen vacancy generation reaction was then explained by the change in the fundamental film parameters including transfer coefficient for oxygen vacancy generation and electric field strength in the film with applied potential and temperature.