著者

佐藤 岳彦 土井 章子 落合 史朗 宮原 高志 藤岡 万也 ラマサミー ラズ 浦山 卓也 中谷 達行

出版者

一般社団法人 日本機械学会

雑誌

年次大会講演論文集

巻号頁・発行日

vol.2005, pp.145-146, 2005

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An atmospheric low temperature plasma flow using a coaxial cable for microwave transmission has been applied to sterilize Escherichia coli to investigate the relationship between gas temperature and sterilization rates. The plasma source mainly consists of a cavity, a quartz discharge tube, a coaxial cable, a microwave power source and a gas supply system. The sterilization rate shows 100% in the center region of plasma exposure when the exposure temperature is 333K. The rate is decreased in the outer region of the plasma exposure. The gas temperature distribution shows the same tendency of the sterilization rate. This implies that the gas temperature is one of sterilization indicators.

著者

佐藤 岳彦 土井 章子 西山 秀哉 藤岡 万也 ラマサミー ラズ 浦山 卓也 藤井 修逸

出版者

一般社団法人 日本機械学会

雑誌

年次大会講演論文集

巻号頁・発行日

vol.2004, pp.57-58, 2004

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A new type of atmospheric low temperature plasma source was developed utilizing a coaxial cable for microwave transmission rather than conventionally used waveguides. The plasma source has advantages such as portability, simple configuration, and ability to operate with wide range of gases and its mixtures. It mainly consists of a cavity, a quartz discharge tube, a coaxial cable, a microwave power source and a gas supply system. Using this plasma source, we tried to clarify sterilization characteristics of Bacillus subtilis. The log reduction numbers of Bacillus subtilis was obtained at least 5 (10^<-5>) under the following operation conditions: gas flow rates of Ar (14 SLM) with mixing oxygen of 0.5 SLM and input power is 400 W. Distributions of temperature and gas velocity were also measured two-dimensionally by using E-type thermocouple and Pilot tube, respectively. The temperature distributions and the peak value of temperature were influenced by the gas flow rate and the kinds of mixing gas. The effective sterilization is obtained under the condition of the substrate surface temperature of 353 K.