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The ozone behavior on heated catalytic probe surfaces is examined in gas flow downstream of atmospheric-pressure dielectric barrier discharge ozonizers. Negative and positive variations in the probe voltage as a function of probe heating current enable one to discriminate catalytic dissociation of ozone at low temperatures and catalytic recombination of oxygen radicals at high temperatures, respectively, on the probe surface. The loss coefficient of ozone on the probe surface derived from the amount of heat removed by catalytic dissociation is of the order of $10^{-4}$ , which increases with increasing probe temperature. The probe temperature decrease per ozone concentration by catalytic dissociation of ozone as a measure of measurement sensitivity increases with probe temperature and is measured typically in the range of 0.5–0.8 Kg $^{-1}\text{m}^{3}$ at ozone concentrations of 10 and 17 gm $^{-3}$ , respectively, showing the applicability of a catalytic probe to a simple sensor body. [ABSTRACT FROM AUTHOR]

A simple heat flow model is established for numerical analysis of the effect of catalytic dissociation of ozone on electrode surface temperature in a coaxial cylindrical-type dielectric barrier discharge ozonizer. The amount of heat consumed by the ozone decomposition at the electrode surface is determined from the balance of heat flow among the discharge gas, electrode, and cooling water. Our calculation using the experimental data shows that the ozone decomposition by 1.6% in total ozone reaching the electrode surface is required to explain the observed temperature decrease from about 20 °C to 8 °C for a stainless steel electrode, while that by 4.5% is needed to explain the temperature decrease from about 20 °C to 19 °C for a copper electrode. The decomposition rates calculated in the discharge are about two orders of magnitude higher than those measured in gas flow downstream of a similar discharge. [ABSTRACT FROM PUBLISHER]

Plasma deposition techniques of nanocrystalline and microcrystalline diamond and related mechanisms at pressures below 0.1 torr are reviewed. The mechanism of nucleation and growth of diamond in low-pressure conditions is discussed theoretically and experimentally along with the role of radicals and ions in two different ion-energy ranges. For ion impact energies below 20–30 eV, diamond deposition occurs on a surface. The growth process is limited by the substrate temperature and the flux of hydrogen radicals when the ion energy is reduced enough to several eV as shown by a kinetic rate analysis for radical species. The nucleation process is limited mainly by the degree of carbon saturation and, hence, the flux of carbon-containing species. For ion impact energies above 20–30 eV, diamond deposition occurs beneath a surface. Renucleation hinders the growth and diamond nanocrystals are embedded in an amorphous carbon matrix. The nucleation process depends strongly upon the ion energy, ion-to-depositing flux ratio, and substrate temperature as shown by the film density increment based on the subplantation model. [ABSTRACT FROM PUBLISHER]

Temperature variation of a catalytic metal surface exposed to ozone produced in an atmospheric-pressure dielectric barrier discharge is examined by using a very thin thermocouple. The metal sheet is heated initially to a certain temperature ( T1) using a resistive heater and, then, the ozone concentration is increased with the heater current unchanged. When T1 is room temperature, the temperature of the metal sheet remains almost constant independent of ozone concentration. When T1 is increased up to 80 °C, the temperature of the metal sheet decreases clearly with increasing ozone concentration due to enhanced catalytic dissociation of ozone at the metal surface. The rate of decrease in temperature for a stainless steel sheet is increased from nearly 0% to $\sim 5.7$ % with increasing T1 from room temperature to 80 °C, while that for a platinum sheet is increased further to $\sim 17.5$ % at 80 °C due to stronger catalytic activity of platinum. The results confirm that the sensitivity for ozone is improved with a stronger catalytic metal heated to a higher temperature as the sensor body. [ABSTRACT FROM PUBLISHER]

An atmospheric-pressure radio-frequency (RF) corona torch plasma and a low-pressure parallel-plate RF plasma are employed to increase hydrophilicity of polycarbonate and acrylonitrile butadiene styrene surfaces. The contact angle of water for the plastic surfaces is decreased by Ar plasma treatment in any condition, while the surface roughness is decreased, too, unexpectedly. The rate of decrease in contact angle versus treatment time in the atmospheric pressure plasma is about an order of magnitude higher than that in the low-pressure plasma. During postexposure of the plastic surfaces to ambient air, the contact angle is recovered gradually and saturated at a certain value depending on plasma treatment time. A longer plasma treatment time causes less recovery in contact angle. The results indicate that surface roughening as well as surface functionalization is responsible for improving the recovery characteristic and, hence, the hydrophilic stability. [ABSTRACT FROM PUBLISHER]

The Asia–Pacific International Symposium on the Basics and Applications of Plasma Technology (APSPT) has been held in Taiwan or Japan every two to four years since 1997. It is an important annual event in the Asia–Pacific area and has been a great platform for scientists all around the world sharing novel and state-of-the-art research findings and exchanging innovative ideas in the field of plasma science and technology. The $11^{\mathrm{ th}}$ APSPT was held on December 11–14, 2019, at Kanazawa University, Kanazawa, Japan. The $11^{\mathrm{ th}}$ APSPT had a very strong program consisting of 13 sessions with 201 articles contributed by the 210 participants from nine countries. This Special Issue focuses on the following topics, which were also the focus topics in the $11^{\mathrm{ th}}$ APSPT. 1)Plasmas in semiconductor materials processing. 2)Plasmas in biomedical and agricultural applications. 3)Plasmas in nano-materials processing. 4)Plasma coating and surface modifications. 5)Plasmas in aerospace/space applications. 6)Plasmas in energy and environmental applications. 7)Plasmas-in-liquid. 8)Multiphase plasmas. 9)Thermal plasmas. 10)Cold plasmas. 11)Plasma diagnostics and modeling. 12)Advanced and novel plasma technologies and sources. As Guest Editors, we thank all the authors, the reviewers, the editors, and the IEEE staff to publish this Special Issue on time. Particularly, we would like to offer our special thanks to the Editor-in-Chief, Dr. S. Gitomer, and the Senior Editor, Prof. P. Chu, for their guidance and help throughout the review process. We hope this Special Issue will help to exchange our knowledge in plasma science and cultivate potential collaboration in the community. We look forward to see all participants again in the $12^{\mathrm{ th}}$ APSPT at Taiwan University of Science and Technology, Taipei, Taiwan, in December 2021. [ABSTRACT FROM AUTHOR]

Pulse-modulated direct-current methane plasmas are used to deposit amorphous diamond-like carbon films on Si and dentistry-use polymethyl methacrylate (PMMA) substrates as a function of the negative pulse voltage applied to the substrate (Vmax). The films on PMMA show a transition from diamond-like to more graphitic carbon in the Raman spectra with increasing Vmax, dissimilar to those on Si. This is attributed to easy deformation of PMMA, leading to the low compressive stress of the films (1 to 2 GPa). The contact angle of water for the films on both Si and PMMA is large, ranging from 79^\circ to 94^\circ almost independent of Vmax, confirming that the films are hydrophobic despite the difference in carbon bonding state. The large dispersion component (41–43 \mJ/m^2) of the surface free energy of the films measured from the contact angle of water and 1-bromonaphthalene indicates the high mass density of the films. The small polar component (0.2–3.5 \mJ/m^2) is attributed to hydrogen saturation of the surface sites forming nonpolar C–H bonds and, thus, responsible for the hydrophobic behavior. [ABSTRACT FROM PUBLISHER]

The Asia-Pacific International Symposium on the Basics and Applications of Plasma Technology (APSPT) has been held in Taiwan or Japan every two–four years since 1997. It is an important annual event in the Asia-Pacific area and has been a great platform for scientists all around the world sharing novel and state-of-the-art research findings and exchanging innovative ideas in the field of plasma science and technology. The 10th APSPT was held on December 15–17, 2017 at Chung Yuan Christian University, Taoyuan, Taiwan. There has been a very strong program including 207 papers contributed by participants from eight countries. This Special Issue focuses on the following topics, which were also the focus topics in the 10th APSPT [ABSTRACT FROM AUTHOR]

The Asia-Pacific International Symposium on the Basics and Applications of Plasma Technology (APSPT) has been held every two to four years since 1997, promoting an Asia-Pacific essential networking to share most innovative research results in low-temperature plasma society, in Taiwan until APSPT-8, 2013. In the meantime, it first changed its venue to Nagasaki, Japan, from APSPT-9 in 2015, to further expand its international role in scientific community with industrial society. At the same time, it was jointly organized with the 28th Symposium on Plasma Science for Materials, which was originated as the International Symposium on Plasma Chemistry since 1987, cultivating the international interdisciplinary field in both basic plasma science and practical applications based on materials science. [ABSTRACT FROM PUBLISHER]

The Asia-Pacific International Symposium on the Basics and Applications of Plasma Technology (APSPT) has been held in Taiwan every two to four years since 1997. It is an important annual event in the Asia-Pacific area, providing an excellent platform for exchanging new ideas and sharing the most advanced knowledge in plasma-related science and technology. Thanks to the participants from 10 countries, in the 8th APSPT, we had a very strong program with 187 papers delivered at National Chiao Tung University, Hsinchu, Taiwan, in December 20–22, 2013. This special issue documents the selected presentations in all kinds of plasma science and technology. There were 51 papers submitted after the conference and 32 accepted to be published in this special issue. We also thank the authors, the reviewers, the editors, and the publisher, who have seamlessly worked together to publish this special issue in time. I hope it will help advance our knowledge in plasma science and technology and cultivate future scientific collaboration among those who participated in APSPT 2013. I look forward to seeing all participants again in the 9th APSPT at Nagasaki University, Japan, in December 2015. [ABSTRACT FROM PUBLISHER]