Cyclodextrins (CDs) have been found to form inclusion complexes with various polymers with high specificity to give stoichiometric compounds in crystalline states. In these complexes, polymer chains were threaded into cyclodextrins and recognized by the host. For example, α-Cyclodextrin (α-CD)formed complexes with polyethylene glycol (PEG) of molecular weight higher than 200, although β-CD did not form complexes with PEG of any molecular weight. However, β-CD formed complexes with polypropylene glycol (PPG) of various molecular weights with which α-CD did not form complexes. γ-CD formed complexes with poly (methyl vinyl ether) (PMeVE), though α- and β-CD did not form complexes with PMeVE. α-CD formed complexes with oligoethylene, but γ-CD formed complexes with polyisobutylene. The structures and properties of the complexes have been studied by spectroscopic methods. Polyrotaxanes in which many CDs are threaded on a single chain were prepared by capping the chain ends with bulky groups.

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The surface enhanced Raman scattering (SERS) spectra are measured for alanine and glycine adsorbed on the silver electrode. The SERS spectra of these adsorbed amino acids differ markedly from of the crystals and the aqueous solutions. Each of the SERS spectra shows characteristic changes with change of the potential of the electrode and the influence of solvent. When the potential applied on a working electrode is 0.4 V or 0.6 V, the bands shift remarkably and are enhanced very much. From the frequency shift of the bands at these potentials, it is concluded that both the amino and carboxyl groups are adsorbed on the surface of silver metal electrode.

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Solid oxide fuel cell (SOFC) without the need for the geometry of two electrode compartments has been developed using partial oxidation of methane. When a gaseous mixture of methane and air (methane: O₂ mole ratio =2: 1) was introduced into Pt/yttria-stabilized zirconia (YSZ)/Au or Pt SrCe_0.95Yb_0.005O₃-α/Aucell at 950°C at a rate of 210 ml min-1, methane was oxidized to H₂ and CO over the Pt electrode, but inactive to O₂ over the Au electrode. This situation led to a large difference in oxygen or hydrogen concentration between two electrodes, resulting in an electromotive force in these cells: 200 mV in Pt/YSZ/Au cell and 700 mV in Pt/SrCe_0.95Yb_0.005O₃-α/ Au cell. The current could be drawn from these cells. The maximum power output of Pt/SrCe_0.95Yb_0.005O₃-α/ Au cell was 0.021 W cm-2, which was about 100 times that obtained from Pt/YSZ/Au cell. The difference in SOFC characteristic between these cells was studied by various electrochemical techniques.

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The changes of the surface properties of graphite powder with direct fluorination in the temperature range from room temperature (RT) to 300°C were investigated by measuring dispersion stability and water adsorption. The state of the flaorine atoms on the graphite surfaces was also examined by X PS analysis.
The dispersion stability of graphite powder in water largely increased by surface modification of direct fluorination at RT, and decreased gradually with increasing fluorination reaction temperature. Also, graphite powder with surface fluorination at 300°C did not invade in w ater, but floate d on the surface of water.
The water adsorption showed that the surface fluorination at RT provided hydrophilic graphite powder, increasing dispersion stability. While the surface fluorination at higher reaction temperature provided gradually hydrophobic graphite powder, decreasing dispersion stability.
The hydrophilic surface comes from introduction of t he ionized flu orine atoms, while the hydrophobic surface comes from formation of the C-F covalent bonding, according to the XPS analysis.

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The silicate layers of montmorillonite clay were pillared with TiO₂ sol particles in aqueous media. The water remained in the pillared clay was replaced with ethanol, whchi in turn was extracted with supercritical fluid of CO₂. The supercritically dried (SCD) pillared clays had porosities as large as ∼0.6 ml/g, and showed little hysteresis on the nitrogenadsorption-desorption isotherms. Platinum was deposited onto the SCD pillared clays by two diffrent methods; (I) impregnation of hexachloroplatinic (IV) acid followed by hydrogen reduction at 400°C, and (II) photoelectrochemical deposition from hexachloroplatinic (W) acid solution. The latter sample was so active in photocatalytic oxidation that 50ppm of carbon monoxide in a stream of air with a space velocity of 9000 h^-1. could be almost completely converted by photochemical oxidation at room temperature. Electron microscopic as well as CO adsorption studies suggest that the high catalytic activity can be attributed to the high dispersiveness of the TiO₂ sol particles between the silicate layers and the smallness of the platinum particles effectively lo aded on the sol particles.

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The formation and the stability of Fe-K double oxides have been examined to study the active component in the dehydrogenation catalysts consisting of Fe₂O₃ and K₂CO₃ using for styrene synthesis. Although formation of KFeO₂ and K₂O. nFe₂O₃ was observed by solid state reaction of Fe₂O₃ and K₂CO₃at 900°C, only KFeO₂ was found inthe reaction at 750°C. Addition of K₂CO₃ to Fe₂O₃ improvedthe catalytic activity and selectivity significantly, independent of the amount of K₂CO₃. The surface composition of Fe-K oxides calcined at 750°C was measured by XPS, and the surface seemed to be covered by KFeO₂.
The stability of KFeO₂ was examined in different atmosphere, and it decomposed in CO₂ at the ternperature of dehydrogenation reaction. However it remained stable after the reaction, although CO₂ was present in the reactor. We tried to measure the equilibrium pressure of CO₂ (Pco₂) which was evolved by the solid state reaction of Fe₂O₃ and K₂CO₃ to form KFeO₂. We found that in typical reaction conditions Pco₂ was less than equilibrium, and so KFeO₂ was stable in it. By addition of CO₂ in the reactor, the catalytic activity and selectivity rapidly dropped when Pco₂ was higher than equilibrium pressure, but stayed constant when Pco₂ was less than equilibrium pressure. Thus we finally concluded that KFeO₂ is the active component in the dehydrogenation catalysts consisting of Fe₂O₃ and K₂CO₃.

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The composite catalysts consisting of aluminum complexes and silanol derivatives were found to accelerate the addition reactions of epoxy resins and aromatic amines. Catalytic activity was not observed, when one of the catalyst components was absent. Triphenylsilanol was more active than alkoxysilanes which were decomposed thermally to form silanol. The acceleration effects were observed even with a small amount of the catalyst i. e., less than 1 wt% of catalyst. Catalytic activities varied with the pKa value of aromatic amines. The DSC curves of the product from epoxy resins and aromatic amines with the composite catalyst showed exothermic peaks 20∼25°C lower than that of non-catalyst resin. The epoxy resins cured with the composite catalyst exhibited excellent electrical and mechanical properties which met to electrical and space/aeronautical applications.

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Imidodiphosphates (RO)₂P (O)NHP (O) (OR)₂ were synthesized, and their thermal behaviors and cleavage mechanism by electron impact were investigated. TG-DTA measurement of eight alkyl imidodiphosphates (IPTA) under nitrogen showed a major weight loss at a temperature, which shifted to a higher degree with increased length of the alkyl chains. But the temperature for IPTAs with branched alkyl chains shifted to a lower degree than that for IPTAs with linear alkyl chains. Four imidodiphosphates (IPTP) with p-substituted phenyl groups showed no characteristic differences depending on the substituent group. The measurements with the TG-TRAP-GC/MS combined system revealed that in the pyrolysis of IPTA (R: - CH₃) methanol might be eliminated in the initial stage and rapidly react with the IPTA to form trimethyl phosphate and dimethyl phosphoramidate. Same pyrolysis mechanism was suggested for four IPTPs. The pyrolysis mechanism of the other seven IPTAs differs: elimination of olefin might occur through the transition state with a quasi six-membered rin g containing oxygen atom of the phosphoryl group and hydrogen atom of the methyl or methylene group. When the fragmentation of IPTA (R: - CH₃) was initiated by electron impact, the elimination of the methoxyl cation from the molecular ion was observed. But the fragmentation of the other seven IPTAs occurred by the elimination of the olefin ion from the molecular ion accompanying one proton or two protons rearrangments. The difference between the cleavage mechanism by electron impact and the pyrolysis was elucidated.

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Boehmite sols were prepared by hydrolyzing three kinds of aluminium alkoxides with hot water. The effect of hydrothermal treatment on the resultant sols was studied through the microstructural cha nge from boehmite to α-Al₂O₃ by heat treatment up to 1600°C. Acetic acid or propionic acid was chosen as a peptizer for the boehmite sol, because the clear sol was obtained and it turned to the clear gel easily. The particle size of the boehmite sol became large by the hydrothermal treatment. The boehmite with large particle was transformed to α-Al₂O₃ by the heat-treatment at 1200°C, but the crystal growth proceeded more slowly compared to that without hydrothermal treatment. In the heat-treatment temperature (HTT) range of 1100 to 1150°C, spherular growth centers appeared and they grew up to form spherulites. The development of spherulites could be seen clearly on the hydrothermal treated boehmite.

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Reactions of transition metal nitrides were investigated with covalent nitrides of IIIb metals and with ionic nitrides of II a metals at high temperatures. NbN reacted with wurtzite-type GaN under a high pressure of 3 GPa to form rock salt-type solid solutions of (Nb_1-xGa_x)N (x≤0.12). The crystal structure was assumed to be locally distorted in the rock salt-type lattice. The reaction of Ni with alkaline earth metal nitride gave linearly coordinated nickel nitrides, CaNiN, its solid solution (Ca_1-xSr_x)NiN with infinite linear chains of (Ni-N_2/2)^2- and SrNiN with zig-zag (Ni-N_2/2)^2- chains. A₃MN₃ (A= Ca, Sr, M = V, Cr, Fe, Co) having trigonal planar MN₃^6- anions were obtained in reactions of M with alkalin e earth metal nitrides. The nitrogen atoms are covalently bonded to the transition metals in these alkaline earth-transition metal nitrides. The differences in crystal structures in these alkaline earth-transition metal nitrides were discussed in relation to the electron configuration of the transition metals and the size matching of the alkaline earth cation with the anionic group.

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Fluorescence quenching of chlorophyll a, chlorophyll b, pheophytin a and pheophytin b by oxygen in acetone, methanol and ethanol was examined by monitoring quenching rate constant (k_Q), respectively. In terms of relationship between the quenching rate constant and viscosity and/or ionization energy of solvent (Figs 3 and 5), it was suggested that the interactiOn between solvent and chlorophyll inhibited formation of contact pair with oxygen. The values of quenching rate constant of chlorophyll derivatives in acetone were as follows; chlorophyll a (4.77×10⁹ dm³ mol^-1 s^-1). chlorophyll b (6.41×10⁹), pheophytin a (6.00×10⁹), pheophytin b (7.58×10⁹), pyrochlorophyll a (5.31×10⁹), pyrochlorophyll b (7.14×10⁹), pyropheophytin a (6.47×10⁹), pyropheophytin b (8.39×10⁹), methyl pheophorbide a (5.97×10⁹), methyl pheophorbide b (6.79×10⁹ ) showing that the general order of fluorescence quenching ability of oxygen is pheophytins>chlorophylls and b series>a series.
Among the ten pigments examined, the quenching rate constant appears to parallel sum of the ratio of group electronegativity and molar volume for substituent of the pigments (Fig.6).

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Tetrabromophenolphthalein ethyl ester (Htbpe) reacted with aliphatic amines to form hydrogen-bonded complexes in 1, 2-dichloroethane.
Absorption max imum of each associate occurred at ca.560 nm for primary amines, ca.570 nm for secondary amines and ca.580 nm for tertiary amines, respectively. Maximum wavelength shifted to longer wavelengths with increasing basicity of amines, but not with increasing carbon numbers. Association constants (log K_a0) of complexes with Htbpe at 20°C were ca.3.5 for primary amines, ca.4.7 for secondary amines and ca.5.1 for tertiary amines; magnitude of the constants was characteristic to each family of amines. And also, the association constants decreased with increasing measuring temperature. The thermochromism of the associates can be applied to the fractional determination of tertiary amines in the presence of primary amines. For example, 2×10^-5 mol/dm³ tributylamine in the presence of (0.5-4)×10^-5 mol/dm³ butylamine was analyzed. Interferences at 20°C was very strong, but at 60 °C, absorbance of interfereing associates disappeared completely and tertiary amines could be detected within an error of 1.5%.

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Single crystal of calcium oxalate trihydrate was synthesized by PFHS method. Dimethyl oxalate was added to the aqueous solution of calcium chloride at pH = 3 and 3°C. The single crystals were obtained and analyzed by thermal analyses, infrared spectrum, X-ray powder pattern and single crystal X-ray structure analysis. The crystallographic constants are as follows. Space group: P¹, cell constant: a=7.1577(8)Å, b=8.4484(8)Å, c=6.1040(5)Å, α=109.722(6)°, β=109.316(7)°, γ=76.5 26(8)°, Z=2, V= 324.8 (1) ų, d=1.862 g cm^-3. Three thermal analyses (TG, DTG, DSC) showed two kind s of releases of hydrate water molecules at 80-105°C (-2H₂O) and 115-170°C (H₂O). The activation energies for the two step dehydration reactions were calculated to be 87.9 kJ mol^-1 (for 2H₂O dehydration)and 105.3 kJ mol^-1(forH₂O dehydration). These results were discussed along with the numbers of the hydrogen bondings around the different types of water molecules, which were found in the X-ray structure analysis.

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We have developed a novel method of acetal synthesis from olefins and alkyl nitrites in high yield using palladium catalysts inthe liquid-phase reaction. The conversion of acrylonitrile into acetal was especially reported in this paper. We have found that palladium, halide ion (Cl^-, Br^-), alkyl nitrites and alcohols were essential in the reaction. The molar ratio of halide ion/Pd remarkably influenced the reaction rate of acetalization. The reaction rate was faster than that of Wacker-type oxidative reactions. The reaction mechanism will be proposed.

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Ability of ionically modified poly (vinyl alcohol) (PVA) with a dodecylthio end group as a dispersant for coal-water slurry (CWM) was investigated. The ability was lower in the case of PVA with no ionic groups compared with sodium salt of naphthalenesulfonic acid-formaline condensate (NSF). By introducing sodium sulfonate groups to the PVA with copolymerization, the viscosity of the CWM was lowered markedly and a dilatent fluidity occurred at lower shear rate region below 100 s-1. In the case of sodium carboxylate groups instead of sodium sulfonate groups, the phenomenon was similar. In the case of quaternary ammonium salt groups, the fluidity of the CWM immediately after preparation was poor and the viscosity was high. Precipitation took place in the CWM using the PVA containing 3 mol% sodiurn sulfonate after 3 days storage. With increase in the amount of sodium sulfonate groups, the storagestability of CWM was improved. Shear viscosity of CWM was studied with changing the shear rate up to 400 s-1. While CWM using NSF showed large thixotropy in the first-run, that using PVA containing 3 mol% sodium sulfonate groups revealed dilatency at lower shear rate range and weak thixotropy at higher shear rate over 120 s -1. Poor storage-stability of the CWM using the PVA seemed to coincide with the absence of increase in viscosity at lower shear rate.

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