4-(4-Octadecyloxyphenyl)ethynylpyridine (ODOP) with amphiphilic property was newly synthesized. Ultra thin films of ODOP were prepared by use of the Langmuir-Blodgett (LB) and self-assembly techniques. The most suitable surface pressure was estimated to be 49.0 mN m⁻¹ for the preparation of ODOP LB films. It was found that self-assembly monolayers of ODOP are not formed at concentrations below 3.0 × 10⁻⁴ mol dm⁻³. There may be a critical concentration for the formation of self-assembly monolayers of ODOP. The electronic structure of these thin films were investigated by use of electronic absorption, polarized electronic absorption and X-ray photoelectron spectra. It was found that the structures of the two films prepared by the LB and self-assembly methods are essentially identical. The X-ray photoelectron spectra of the LB films prepared with the various surface pressures were measured. ODOP in cyclohexane shows the first electronic band at 316.9 nm in monomolecularly dispersed systems. The first electronic band splits into two bands, an intense 306 nm band and a weak ≈350 nm band, upon the formation of ultra thin films. Using the concept of the exciton splitting model, the behavior of the first electronic transition of ODOP was explored, and it was found that the molecular orientations in the ultra thin films are of herring bone.

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The homogeneous hydroformylation of 1-undecene catalyzed by triazenidorhodium complex [Rh(Ph₂N₃)(CO)(PPh₃)₂] in several solvents (toluene, benzene, acetone, and tetrahydrofuran) was studied at 313 K. The products were dodecanal and 2-methylundecanal at 1.0 × 10⁵ Pa of synthesis gas (CO/H₂ = 1/1), the amount of dodecanal being larger than that of 2-methylundecanal. A small amount of 2-undecene was also obtained by isomerization of 1-undecene.
In the case of toluene as solvent, the maximum yields of dodecanal and 2-methylundecanal were obtained at 1.0 × 10⁵ Pa of synthesis gas pressure, while the formation rate of 2-undecene decreased with increasing the synthesis gas pressure from 1.0 × 10⁴ to 1.0 × 10⁶ Pa. The maximum yields of dodecanal and 2-methylundecanal were obtained at 323 K, while the formation rate of 2-undecene was accelerated by elevating the reaction temperature in the range from 303 to 333 K at 1.0 × 10⁵ Pa of synthesis gas pressure. Moreover, the induction period was observed by adding PPh₃ into the reaction system at 313 K, 1.0 × 10⁵ Pa of synthesis gas pressure. Contrastively, a large amounts of PPh₃ inhibited the reaction of hydroformylation and isomerization of 1-undecene. A plausible mechanism for hydroformylation was proposed.

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Solar thermal cell converts low temperature solar thermal energy into electric power. It consists of chemical reactions of 2-propanol dehydrogenation and acetone hydrogenation, and a fuel cell. In this study, we studied photocatalytic 2-propanol dehydrogenation in order to apply directly sunlight to the solar thermal cell. Noble metal (Pt, Ru, Rh and Pd) supported on TiO₂ was used as a catalyst and we compared the result of photocatalytic 2-propanol dehydrogenation with that of 2-propanol dehydrogenation using carbon-supported noble metal catalyst. A metal loading ratio was 5 wt%. Three kinds of TiO₂ (Ishihara Sangyo Kaisha. LTD: ST-01, ST-21 and ST-31) were used in this study. We examined the activity of various combinations of noble metal and TiO₂ for the reaction under boiling condition and below boiling point with using high pressure mercury lamp, and we evaluated the reaction mechanism. Platinum catalyst supported on ST-01 has the highest activity. Photocatalytic 2-propanol dehydrogenation with using noble metal supported on TiO₂ is characterized by small retardation by acetone and large hydrogen evolution rate below boiling point. It is suggested that once acetone and molecular hydrogen are formed on the catalyst surface, they don’t remain on the surface and they are easily desorbed from the catalyst.

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Mechanical and morphological properties of methyl methacrylate-butyl acrylate-acrylic acid copolymer emulsion films were investigated. As a result, the elevation of drying temperature accelerated the coalescence of polymer particles. The coalescence of polymer particles was completed at drying temperature above 48 °C from MFT (minimum film-forming temperature). In addition, the surface of the film was very flat like the surface of polymer solution film. We found out that the Ra (surface roughness) of the film surface had a relation with the coalescence rate of polymer particles. Moreover, we found out that the tensile strength and the peel strength of the film increased with the decrease of Ra. The water absorbing capacity of the film had no relation with the coalescence rate of the polymer particles.

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Dissolving characteristics of LaNi₅ based hydrogen storage alloys and their corrosion products (hydroxides of rare earth elements + fine nickel and cobalt metal particles) were studied by immersing them in a chromic acid aqueous solution. The hydroxide layers on the alloys dissolved into the 5 mass% chromic acid aqueous solution without dissolving the alloys themselves. The composition of hydroxide layer was analyzed by measuring the dissolved amount of the alloy elements in the solution by ICP-AES. The amount of fine nickel and cobalt particles was estimated by magnetization measurement. The composition of the corrosion layer on the alloy was quantitatively analyzed.

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This paper discribes the regeneration method of the deteriorated oxygen transport membrane using N,N′-bis(3-methoxysalicylidene)-2-methylpropylenediaminatocobalt(II) with 4-methylaminopyridine as an axial ligand. When the deteriorated complex solution exposed to O₂/N₂ mixed gas for 140 hours was brought into contact with Zn at 423 K, the O₂/N₂ selectivity (α) of oxygen transport membrane restored the initial value 110 from 2.2, and Co(II) concentration increased to the initial concentration 0.4 mol L⁻¹ from 0.05 mol L⁻¹. The O₂/N₂ selectivity (α) of the complex solutions treated with Fe, Mg, Al were 39, 1.5 and 1.5, respectively.
When the deteriorated complex solution, to which 17 wt% of water was added, was heated at 423 K, the O₂/N₂ selectivity (α) of the complex resored to 115 from 4.1, and the water concentration decreased to the initial concentration, 0.2 wt%. When the deteriorated complex solution exposed to air for about 48 hours was brought into contact with Zn at 423 K, the O₂/N₂ selectivity (α) of the complex solution regenerated to 116 from 2.1 and water concentration decreased from 15.8 wt% to 0.2 wt%. It was also shown that the repetitive regeneration of the deteriorated complex solution is attainable by Zn contact.

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The effect of precursors on CO₂ hydrogenation reactivity was observed over Rh–Li/SiO₂ and Rh–Fe/SiO₂ catalysts prepared by co-impregnation method. The highest CO₂ conversions were obtained over the catalysts prepared from Rh acetate and additive nitrate. For the catalysts prepared from chloride precursor, CH₄ selectivity was high but CO one low. On the other hand, the catalysts prepared from non-chloride precursors showed high CO selectivity and low CH₄ one. The Rh–Li/SiO₂ catalyst prepared from Rh nitrate and Li chloride, and the Rh–Fe/SiO₂ one prepared from Rh acetate and Fe nitrate showed the highest ethanol selectivity, respectively.

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