Online ISSN : 2186-2451
Print ISSN : 1344-3542
ISSN-L : 1344-3542
76 巻, 5 号
  • Sadayuki KIKAWA, Noriyuki KITAORI
    2008 年 76 巻 5 号 p. 330-333
    発行日: 2008/05/05
    公開日: 2012/03/22
    ジャーナル フリー
    In this study the bleaching effect of electrolyzed water prepared from sodium chloride (NaCl) solutions was investigated by bleaching tea-stained cotton cloths. The bleaching performance of the electrolyzed water was higher than that of a sodium hypochlorite (NaOCl) solution with the identical available chlorine concentration (ACC) and pH, but the bleaching performance of NaOCl solution was increased to close to that of the electrolyzed water by adding NaCl. Interestingly, the effect of electrolyzed water also increased with the increase of initial NaCl concentration, even when keeping the ACC constant. These phenomena suggested that the improvements in the bleaching effect are caused by coexistent NaCl. It could be explained by Le Chatelier’s principle, that is, non-ionized NaOCl which has higher bleaching effect than ionized NaOCl (OCl) would be produced by the shift of equilibrium (Na++OCl+NaCl→NaOCl+Na++Cl). This behavior was also indicated from the UV absorption spectra before and after adding NaCl to the NaOCl solution.
  • Hisashi KATO, Hiroo YUGAMI
    2008 年 76 巻 5 号 p. 334-337
    発行日: 2008/05/05
    公開日: 2012/03/22
    ジャーナル フリー
    The total electrical conductivities of Sr2+ and Al3+-doped LaScO3 materials, La1−xSrxSc1−yAlyO3 (x=0.1–0.325, y=0–0.01), were examined under wet, dry, reduced and oxidized conditions and were found to express mixed ionic and electronic conductivities. In the high temperature range of 1073 to 1273 K, oxide-ion conduction was predominant. In the systematic measurement of electrical conductivity, we found that the oxide-ion conductivities and activation energies show continuous changes over a wide range of Sr2+ dopant concentrations. We also found that oxide-ion conduction was enhanced by Sr2+ doping to the La3+ site. The ionic transference number, tion, calculated from the conductivity data under high and low P (O2) conditions was 0.73 (x=0.325, y=0.01) at 1273 K.
  • 竹村 大吾, 光田 憲朗
    2008 年 76 巻 5 号 p. 338-342
    発行日: 2008/05/05
    公開日: 2012/03/22
    ジャーナル フリー
    The positive electrode area of an EDLC where doesn’t face to a negative electrode (PE non-confrontation area) was known as an easily deteriorate area. However, it didn’t know that cause. In this paper, in the first, it was confirmed by an experiment a remarkable decline of the performance of an EDLC with non-confrontation area, and an unusual corrosion near the PE non-confrontation area also was observed. In the second, multi-probes (three lithium-metal reference electrodes) were set around an EDLC, and voltage changes among the electrodes were evaluated. Significant electric potential shifts were observed between the three reference electrodes near the area where positive and negative electrodes were not faced each other. The potential shifts were canceled after more than an hour, and the voltage between the three reference electrodes became the same value. To charge and to discharge the PE non-confrontation area several hours were needed. These phenomena can be related to the easily deteriorate area of positive electrode.