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Volatile organic compounds (VOCs) are widely used in various fields such as medicine and industry. However, since these VOCs are often harmful to the human body and are also causative agents of photochemical oxidants and suspended particulate matter, it is necessary to decompose them to below the standard value before releasing them into the atmosphere. Traditionally, VOCs have decomposed using combustion and photocatalytic methods. The combustion method decomposes VOCs with fuel at high temperatures of 600-800°C. This method is suitable for gas decomposition at high flow rates and high concentrations but is not suitable for gas decomposition at low concentrations due to the high energy consumption. The photocatalytic method, on the other hand, is a method of decomposition by the oxidizing action of photocatalyst, which has low running cost and is suitable for gas decomposition at small flow rates and low concentrations but is not suitable for large flow rates. In recent years, atmospheric pressure and low-temperature plasmas have been attracting attention as a low-energy method for decomposing gases with large flow rates and low concentrations. We are developing a large volume processing system using a large dielectric barrier discharge.

現在，トルエンなどの VOC(揮発性有機化合物)は，様々な 工業分野において幅広く利用されている一方，人体への悪影 響や空気汚染の原因となるため大気中へ放出する際には必 ず処理しなければならない。VOC の分解には低消費エネル ギーで大流量，低濃度に適した処理方式が必要であり，その 方法としてプラズマ法が注目されている。我々は，ガス分解 を目的としてプラズマ法を用いた 1 層誘電体バリヤ放電処 理装置の開発をしてきたが，最大流量は 90 L/min と，実用 性を考慮するとさらに大流量で使用したい。そこで本研究で は，1,000 L/min と大流量でのガス分解を目的とし，10 層誘電体バリヤ放電処理装置を開発する。

A stable two-phase sheath flow using tetrahydrofuran (THF) for an inner flow and water for an outer flow was formed in a glass capillary, and worked as a stable liquid-core/liquid-cladding optical waveguide (THF/water LLW). Although THF and water were miscible with any ratio, the length of the stable THF/water LLW at 0.9 - 2.1 cm s-(1) reached at least 150 mm. The THF/water LLW was applied to the observation of extraction behavior of solvatochromic fluorescence dye, 1-anilino-8-naphtalene sulfonate (ANS), through the THF/water interface. ANS was added to the water phase (clad solution) and its fluorescence, which was excited with the guided light (355 nm) through the LLW, was observed by changing the position of the detector. While the ANS stayed in the region of 70% THF to the end of the LLW without the addition of cationic surfactant, hexadecyltrimethylammonium ion (CTA(+)) at pH 3 and 11, the ion-pair of ANS and CTA(+) was extracted into the higher concentration region of THF with the addition of CTA(+) at pH 11.

An octadecylsilica (ODS) column modified with zwitterionic/nonionic mixed surfactants was evaluated for the direct injection determination of inorganic anions in biological fluids by ion chromatography. A zwitterionic surfactant (sulfobetaine-type) and a nonionic surfactant (polyoxyethylene-type) were used for a stationary-phase modification. When aqueous electrolyte solutions with concentrations of sub-mM to several mM were used as a mobile phase, the zwitterionic surfactant coated on the ODS surface exhibited unique separation selectivity for ionic species, while the nonionic surfactant coated on the ODS might have formed a hydrophilic network over the ODS surface and restricted matrix proteins from adsorbing on the stationary phase. Consequently, the mixed surfactant-modified column system allowed an efficient ion chromatographic separation of inorganic anions as well as a size-exclusive removal of column-fouling proteins. This separation system was applied to the direct injection determination of UV-absorbing anions in human saliva. The detection limits for nitrite, nitrate, iodide and thiocyanate were 3.1, 2.7, 4.5 and 25 µM, respectively, with UV detection at 210 nm (injection volume; 20 µl), and their relative standard deviations for 5 replicate measurements of saliva samples spiked with 100 µM each of those anions were 1.4, 0.9, 2.2 and 5.5%, respectively.

An ITO electrode slab optical waveguide spectroelectrochemical measurement system was built for simultaneous Visible attenuated total reflection (ATR) and electrochemical measurements and was applied to study the spectroelectrochemical behavior of iodine at the ITO electrode. The cyclic voltamogram and the potential-absorbance curve at 430 nm for the redox reaction of iodine were observed and the formation of iodine was confirmed by the Visible ATR spectra of iodine (λ_max = 430 nm) which showed blue-shift compared with those of gasous iodine as well as iodine in non-polar solvents (λ_max = 500 ∼ 600 nm). Moreover, the linear responses of the peak current and the maximum absorbance for the oxidation reaction of iodide were obtained to the concentration of iodide in aqueous samples.

名古屋大学博士学位論文 学位の種類:博士(工学) (課程) 学位授与年月日:平成11年3月25日

Al NMR spectra of an equimolar (10 mM) Al(III)-citrate system were obtained at different temperatures. The linewidths of the signals decreased in the spectra recorded at elevated temperatures, which enabled us to unequivocally identify the resonance lines. From the spectrum recorded at 65°C, a mononuclear Al(III)-citrate complex was identified at a solution pH of 3.0 in addition to trinuclear Al(III)-citrate complex, which dominated at pH 4.0.