Eco-Engineering
Online ISSN : 1884-4669
Print ISSN : 0915-4353
ISSN-L : 0915-4353
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Displaying 1-5 of 5 articles from this issue
  • Satoru Fukinbara, Fumihide Shiraishi, Katsuyuki Nakano
    2001 Volume 13 Issue 2 Pages 1-10
    Published: March 31, 2001
    Released on J-STAGE: December 16, 2010
    JOURNAL FREE ACCESS
    In a series of two papers, the performance of a photocatalytic reactor, where a light source is surrounded by an annular array of 19 transparent glass tubes, giving a zigzag-flow path as a whole, has been studied both experimentally and theoretically. In this first paper, the kinds of light source and glass material for such a reactor have been investigated based on the photocatalytic decomposion of 2, 4-dinitrophenol (DNP) in batch-recirculation and continuous-flow modes. The UV light of a blacklight fluorescent lamp was found to permeate through not only a quartz glass tube but also a Pyrex glass tube without reducing its light intensity. The same result was obtained with a white fluorescent lamp. Similarly, the UV light emitted from a germicidal lamp permeated through a quartz glass without reducing its light intensity, but it did not permeate through a Pyrex glass, which resulted in a remarkable reduction in the rate of DNP decomposition. When Pyrex glass tubes were used as a support, the blacklight fluorescent lamp gave a maximum reactor activity. However, the use of the germicidal lamp caused a marked reduction in the rate of DNP decomposition because the Pyrex glass tube completely blocked off the UV light with a wavelength of 254 nm. In the photocatalytic reactor using quartz glass tubes as a support, a rapid DNP decomposition occurred with the germicidal lamp than with other light sources. The white fluorescent lamp gave a slower decomposition of DNP because of a low content of the UV light. Furthermore, when glass beads coated with titanium oxide were packed in Pyrex glass tubes, DNP was more rapidly decomposed using three kinds of the light sources. From the standpoint of the practical use, it is concluded that a combination of the blacklight fluorescent lamp with Pyrex glass tubes is reasonable for the type of the photocatalytic reactor investigated here.
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  • Satoru Fukinbara, Fumihide Shiraishi
    2001 Volume 13 Issue 2 Pages 11-23
    Published: March 31, 2001
    Released on J-STAGE: December 16, 2010
    JOURNAL FREE ACCESS
    In a series of two papers, the performance of a photocatalytic reactor, where a light source is surrounded by an annular array of 19 transparent glass tubes, giving a zigzag-flow path as a whole, has been studied both experimentally and theoretically. In this second paper, the photocatalytic reactor, constituted by a 6-W blacklight fluorescent lamp and Pyrex glass tubes, has been used to carry out the photocatalytic decomposition of DNP. The intrinsic kinetic constant was determined from the initial reaction rate that were measured at high initial reactant concentrations and the intrinsic adsorption equilibrium constant and mass-transfer coefficient were determined by the methods previously established in an immobilized-enzyme system. The result calculated by applying these parameter values to each mathematical model, taking into consideration the effect of film-diffusional resistance, for the photocatalytic reactor system operating in a batch, batch-recirculation, or continuous-flow mode was in good agreement with the experimental values, which indicates the validity of the mathematical models. At an initial DNP concentration of 11.6g m3, the effectiveness factor was 0.92, showing that the effect of film-diffusional resistance is not so high in the present system. Although the experiment was carried out in the batch-recirculation reactor system, the result of theoretical analysis indicated that the present reaction condition can be approximately regarded as the batch reaction condition. The method previously proposed in an immobilized-enzyme system were found to be useful to determine the intrinsic kinetic parameters and mass-transfer coefficient in the present photocatalytic reactor system.
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  • Study on the definition of Ecotourism and its Applicable Way
    Iwamitsu Kaneta, Takeo Kondo
    2001 Volume 13 Issue 2 Pages 25-32
    Published: March 31, 2001
    Released on J-STAGE: December 16, 2010
    JOURNAL FREE ACCESS
    This study was to research the definition of Ecotourism and to propose the new concept of Ecotourism and its applicable way. The new definition of Ecotourism could be characterized as three.
    (1) To experience and learn the intact natural environment, culture, and historical buildings and spots.
    (2) To minimally discontinue the impact to the regional resources by tourism and enhance endeavors to conserve its value.
    (3) To give the pleasure from experiences and the message of the real meaning of preservation and conservation to tourists.
    Then, it is linked to the vitalization of the region. Also, it offers the activities to preserve regional environment, cooperating with both tourists and residents.
    Clarifying Ecotourism clears the two types of Ecotourism. One is “Preservation Type of Ecotourism”, and the other is “Symbiosis Type of Ecotourism”. In Japan, the region, which needs the plan of regional vitalization, has been developed. “Symbiosis Type of Ecotourism” is adapted as the new concept of Ecotourism in this study, and it is used as the main concept for vitalizing regions.
    Finally, the application of “Symbiosis Type of Ecotourism” for vitalizing regions is described. “Symbiosis Type of Ecotourism” is composed of six components, “residents, tourists, travel agencies, local government, researchers, and developers”. They have to cooperate with each other to form the region balanced between natural and historical resources, existing tourism resources, and development.
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  • For International Ecotourism Year 2002: Promotion of Intellectual and Healthy Stimulation
    [in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...
    2001 Volume 13 Issue 2 Pages 33-73
    Published: March 31, 2001
    Released on J-STAGE: December 16, 2010
    JOURNAL FREE ACCESS
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  • Yoshiaki Kitaya
    2001 Volume 13 Issue 2 Pages 90
    Published: March 31, 2001
    Released on J-STAGE: December 16, 2010
    JOURNAL FREE ACCESS
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