CdS and Cd_0.8Zn_0.2S pillars were constructed in the interlayer of hectorite, HNbWO₆, H₄Nb₆O₁₇ and H₂Ti₄ O₉ by the intercalation reactions. The thicknesses of the semiconductors incorporated were less than 1 nm and the band gap energies of them were slightly larger than those of normal crystalline ones. CdS and Cd_0.8Zn_0.2S pillared compounds showed photocatalytic activity for hydrogen evolution and nitrate reduction under visible light irradiation in the presence of sacrificial hole acceptor such as Na₂S and methanol. The photocatalytic activities of the semiconductors incorporated were superior to those of unsupported ones. The incorporation of semiconductors in the interlayers of semiconductor layered compounds such as HNbWO₆, H₂Ti₄O₉ and H₄Nb₆O₁₇ was much more efficient in enhancing the hydrogen production activity than when an insulator such as hectorite was used. The heterogeneous electron transfer from guest CdS to host semiconductor seemed to play an important role to enhance the photocatalytic activity.

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A fluorescent molecular sensing for endocrine-disrupting chemicals and their analogs has been investigated by fluorescence spectral change of regio-selective 1-pyrene-ρ-cyanobenzene-modified γ-cyclodextrins on the addition of a guest. These host compounds showed both monomer and exciplex fluorescence at around 378 and 397 nm, and 468nm, respectively. On accommodation of the guests such as dioxin analogs, p-nonylphenol, 2, 4-dichlorophenoxyacetic acid, bisphenol A, and diethylphthalate, the intensities of the guest-induced monomer fluorescence increased or decreased, and those of the guest-induced exciplex emission decreased. The extent of the fluorescence variations with the guest was employed to display the sensing abilities of these hosts. The sensing parameters, ΔI_m/I⁰_m and ΔI_ex/I⁰_ex, were used to describe the sensing ability of the hosts, where I_m and I⁰_m, and I_ex and I⁰_ex were fluorescence intensities of monomer and exciplex emission, respectively, in the presence and absence of the guest, and ΔI_m=I⁰_m-I_m, and ΔI_ex=I⁰_ex-I_ex. These hosts particularly exhibited high sensitive and selective molecular recognition ability for 2, 4, 6-trichlorophenol, p-nonylphenol and bisphenol A.

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1, 2-Bis (4'-oxa-3', 5'-dioxotricyclo-[4.3.0.1^{2, 5}] decane-8'-yloxy) ethane (BNA), which is a candidate for a monomeric starting material of the soluble polyimide, has been synthesized from 5-norbornene-2, 3-dicarboxylic anhydride (NA) and 1, 4-dioxane (1, 4-DO) via solid acid catalysis over the heteropolyacids such as H₃PW₁₂O₄₀·30H₂O and H₄SiW₁₂O₄₀·30H₂O. In all the conditions without 1, 4-DO, no reaction occurs. Thus, it seems that this novel reaction contains an acid-catalyzed cleavage step of 1, 4-DO by the very strong acidity of the heteropolyacids. The target compound (BNA) can be obtained in satisfactory yields (-90%).

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A thermal conductivity measuring apparatus using both the Guarded Hot Plate (GHP) method and the Cyclic Heat method was designed, and thermal conductivity of a fibrous insulations were measured in atmospheric conditions and in evacuated conditions at temperature range from 100 to 1300°C. When the apparatus using the GHP method was designed, the sizes of the meter and guard heater are determined using the theory by William Woodside. In the Cyclic heat method apparatus, the error magnitude due to difference in period of heat wave was examined, and the time lag method was compared with the amplitude decay method.
The thermal conductivities of the fibrous insulations (aluminum-silica) of both the GHP method and the Cyclic Heat method are in good agreement. This result indicates that values of measurements by the nonsteady state method (Cyclic heat method) is in agreement with the steady state method (GHP method) on proper conditions.
As applied measurement, I compared thermal conductivity of the brick with the fibrous insulation in atmospheric conditions at temperature range from 100 to 1300°C, and examined the relationship between heat flow and different types of fibrous fleeces in a fibrous insulation in evacuated conditions.

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Fog water was collected at the mountainside of Hachimantai range in Northern Japan from June to September in 1998 and 1999. The various ion concentrations in these samples were analyzed, and the fog droplet sizes were measured for each fog event. As the fog droplet size increased, the ion concentration decreased, and the slope of log-log plots of the concentration versus the droplet size was different each other. In order to characterize the air pollutant, moreover, these data were quantitatively analyzed by an oblique rotational factor analysis. We found that three factors were extracted as the air pollutant source; A: (NH₄) ₂SO₄, B: acids (HNO₃+H₂SO₄), C: sea-salt. Combining the factor analysis with the 72 h back trajectory at 850 hPa level, we found that the contribution of each factor varies with the back trajectory. In 1998, the contribution of factor A tends to increase at the trajectories from Northeastern China, while factor C increases at the trajectories through the East China Sea and the Sea of Japan.

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In order to investigate the acidification and pollution of fog, fog water samples were collected in the Akita Hachimantai mountain range at the northern Japan from August to September, 1997 and June to September, 1998 and 1999. The ionic components and the insoluble substances in fog water were analyzed using ion chromatography and Particle Induced X-ray Emission (PIXE) analysis, respectively. Combining a 72h back trajectory to the chemical analysis, the effect of the transportation course of an air mass on the insoluble substances and ionic components in the samples was discussed. When the air mass was transported from the northeastern China to the Hachimantai range, the acidity of fog water was highest in all cases. This acidification was mainly caused by nss-SO₄^2- and NO₃^-. It was found that the fog water in this case would contain “Kosa” as the insoluble substances from the northeastern China.

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Stresses around a propagating finite crack having a constant velocity in an elastic layer sandwiched between two elastic half-planes are determined. The self-equilibrated system of pressure is applied to the crack surfaces. Application of the Fourier transform technique reduces the problem to that of solving dual integral equations. In order to solve the equations, the differences of the crack surface displacements are expanded in a series of functions that are equal to zero outside of the crack. The unknown coefficients in the series are solved using the Schmidt method. The stress intensity factors are calculated numerically for a crack in a layer made of epoxy resin sandwiched between two half-planes made of aluminum.

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