This study aims to separate the polarization resistance of Pt/YSZ air electrodes into two resistance components, i. e., dissociative adsorption resistance and diffusion resistance. Current decay curves were measured by potential-step chronoamperometry and a current decay equation was obtained by solving Fick's diffusion equation under appropriate boundary conditions. The experimental decay curves were fitted to the equation by optimizing parameter values involved in the equation. Diffusion coefficients and rate constants for adsorption were calculated from the parameter values thus obtained. It was found that the rate controlling step depends on temperature, oxygen pressure and sintering temperature of electrodes.

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N-Allylation of imides with allyl alcohol catalyzed by Pd(OAc)₂-bis (phosphine) was investigated. When 1, 3, 5-triazine-2, 4, 6 (1H, 3H, 5H)-trione was used as a substrate, Pd (OAc)₂-dppb[dppb=1, 4-bis (diphenylphosphino) butane] was found to be the most efficient catalyst, and the reaction proceeded effectively in aromatic hydrocarbon solvents such as xylene or toluene at temperatures of 110∼140 °C. For example, 1, 3, 5-trially1-1, 3, 5-triazine-2, 4, 6(1H, 3H, 5H)-trione was obtained in a quantitative yield from a Pd (OAc)₂-dppb (0.1-0.3 mmol) catalyzed reaction of 1, 3, 5-triazine-2, 4, 6 (1H, 3H, 5H) -trione and allyl alcohol in o-xylene at 110 °C for 4 h. Similarly, various N-allyl imides were also synthesized in high yields from allyl alcohol and the corresponding N-unsubstituted imides, such as succinimide, phthalimide or hydantoin. Reactions of succinimide and various allylic alcohols were also examined, and a reaction mechanism including a π-allylpalladium complex formed by the oxidative addition of allyl alcohol was proposed.

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The decomposition of N₂O was carried out with several copper catalysts such as copper ion-exchanged ZSM-5, mordenite, and Y-zeolite, cupric oxide supported on y-alumina, and perovskite-related La_1.5Sr_0.5CuO₄. The amounts of copper exposed on the surface were estimated by NO adsorption at 273 K and N₂O oxidation at 363 K. It was found that more than 80% of t otal copper ions w ere expose d on t he surface for ZSM-5, 50--60% for mordenite, and less than 20% for Y zeolite and y-alumi na. The catalytic activities, expressed by the rate of N₂O decomposition per surface copper (Turnover Frequ ency, TOF), increased greatly with an increase in the copper content for ZSM-5, while it increased only slightly for mordenite, Y zeolite and y-alumina. The TOF of ZSM-5 was a bout 100 t imes greater t han those of mordenite, Y zeolite and y-alumina when compared at the copper weight content of 5 %. L a_1.5Sr_0.5Cu₄, which had a very small specific surface area due to high-temperature calcination, sho wed much greater TOF than mordenite, Y zeolite and y-alumina, but lower than ZSM-5. The exam ination of the diffusion constraints within the zeolite pore system revealed that catalytic effective ness factors were approximately unity, so t hat the dinsion of N₂O in micro and meso pores did not affect the reaction rate and TOF observed in this work would reflect the intrinsic catalytic activity.

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The composition and configuration of imidazoles-nickel (II) acetate complexes and insoluble matters obtained from these complexes were determined by the elemental analyses, the spectral and magnetic analyses, and the thermal properties were also investigated. The complexes of [NiA₂(HL)₂] (HL:HIm, 2-CH₃ HIm, 2-C₂H₅ Hlm, 2-(CH₃)₂ CH⋅HIm, 4-CH₃⋅HIm, A: CH₃COO^-) type, and [NiA₂(HL)₄]and [Ni(HL)₆]A₂ (HL:HIm, 4-CH₃⋅HIm, A:CH₃COO^-) types indicated the octahedral configuration in the solid state and in the alcoholic solution. The yellowish insoluble matters which are represented with the composition of [NiL₂] (L: im-, 2-CH₃⋅im^-, 4-CH₃⋅im^-) were obtained by refluxing the ethanolic or 1-propanolic solution of the others except for the complexes consisting of 2-C₂H₅ HIm and 2(CH₃)₂CH HIm, but did not produce from the methanolic solution. These insoluble matters were the polynuclear complexes to contain a chain structure consisting of the square planar nickel (II) unit. The formation process of such polynuclear complexes was also discussed.

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A general synthetic method of allylimidothioates (1) was established by the reactions of allyl bromides with various thioamides in aprotic solvents under mild conditions.
5-Bromo-4H-5, 6-dihydro-1, 3-thiazines (2) and 4-bromomethyl -4, 5-dihydrothiazoles (3) were synthesized by intramoleculer cyclization of the allylimidothioates (1) with N-bromosuccinimide (NBS) or bromine in dichloromethane at room temperature. In these reactions, (E)-1 gave trans-2 and anti-3; on the other hand, (Z) -1 afforded cis-2 and syn-3, respectively.
Reaction of 3-butenylimidothioates (1h) with NB S afforded only 2-substituted-3-bromothiolane derivative (20) instead of expected tetrahydrothiazepine (21) or dihydrothiazine derivative (22).
Synthetic applications and plausible mechanisms of these reactions were described.

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In reductive methylation reaction of coal using molten potassium, relations between reaction time of anionization and solubilization have been studied. Three kinds of coals of different coalification degree were reacted with variable reaction times (30∼360 min) of anionization. In about 30 minutes of anionization time, 6∼7 methyl groups per 100 original carbon atoms were introduced and a remarkable increase of pentane- and benzene-soluble products were obtained. From these results, it was considered that the solubilization was caused by scission of C-O-C bonds and subsequent introduction of methyl groups in chemical unit of coal structures, and that these reactions occurred remarkably in early stage of anionization. Better yield of the soluble products was obtained from high rank coal (Kairan) than low rank coal (Yùibari and Kitadein), and some continuous increase of the yield (up to 75%) were obtained for high rank coal by the scission of remaining C-O-C bond and introduction of methyl groups, while increase of the yield after initial stage was not observed for low rank coals.
The difference of the solubilization character among various coa ls was considered to depend on amount of ether linkages, bridged structures by functional groups, size of aromatic rings, and so on, in original coal structures.

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Reduction of cracked residue of thermosetting resin (TSR) was studied to improve oil recovery from waste plastics that include TSR. In the process of thermal decomposition, resin turns to residue through crosslinking and cyclization by radical recombination. Inhibition of radical recombination was investigated by means of addition of thermoplastic resin (TPR) as a radical acceptor to TSR during pyrolysis. Epoxy resin (EP; TSR) was pyrolyzed at 500 °C for 1 hour and 23 wt% of EP turned into residue. By addition of polyethylene (PE; TPR) to EP (PE: E P=, 4: 1, weight base), residue of EP was reduced to 5wt%. On the other hand, decomposition of residuewas not observed when residue of EP was pyrolyzed with PE. From TG-MS study of cracked gas from EP and/or PE, it was indicated that reduction of residue was caused by intermolecular reaction between EP and PE.

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Anti-microbial materials were synthesized with thiosulfatosilver complex on silica gel. Release ratio of the effective component from the materials was improved with coating on the surface with hydrolyzed tetraethoxysilane (TEOS). It was observed by EPMA (Electron probe micro analyzer) that the effective component from the materials was leached out around the materials through the resin. It was also confirmed that the coating was effective for the improvement of release ratio with increasing amount of TEOS used.

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The solubilities of lanthanoid hexacyanocobaltates (III) in water at 298.2 K were determined by inductively coupled plasma emission spectroscopy. The lanthanoid complexes Ln[Co(CN)₆]⋅nH₂O (Ln= La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu;n=4 La-Nd, n=5 Sm-Lu) were prepared by mixing aqueous solutions of the corresponding lanthanoid nitrates and potassium hexacyanocobaltate (III) at room temperature. The dependence of the solubility of lanthanoid hexacyanocobaltates (III) in water on the ionic radii of the trivalent lanthanoid ions is discussed. The solubility decreases monotonically with the decrease of the ionic radius from lanthanum to tdrbium, and then increases very slightly. The result was considered owing to the difference of the hydration structure of trivalent lanthanoid ions in aqueous solution.

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The migration of the counter anipns of tetramethylammonium salts such as chloride, formate, sulfate, and hydrogencarbonate ions through the membrane to the catholyte in electrolysis of thoses alts was studied. In the case of the formate and sulfate ions, themigration kept therule of an exponential function to the consumed charge. On the otherhand, in the case of the chlorideion, it was in direct proportion to the charge. The order of the amount of the migration of anions was asfollows; formate>chloride>su1fate>hydrogencarbonate. There ason for the extremely low concentration of hydrogencarbonate ion (orcarbonateion) in the catholyte was that CO₂ gas was already saturated in the anolyte at the beginning of the electrolysis.

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In applying an inductively coupled thermal plasma of argon to spray of hydroxyapatite (HAp) on titanium substrate, a part of HAp powders reacted with the substrate to form a layer, which could not be identified with any of JCPDS. In order to eliminate any effects due to the spraying from determination of the substrate temperature at which the layer was formed, fine HAp powders on the substrate were heated by the plasma. The temperature dropped from 1123 K to 1013 K, when the plasma working gas of argon was added with hydrogen.

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Inverse gas chromatography was applied to study the surface properties of TiO₂ used as pigments for cosmetics. The titania surfaces were modified by various silane coupling agents. Retention volumes for a series of n-alkanes and polar probes were measured using these titania as the column packing. Retention data for nonpolar probes were shown to be dependent on the properties of modified surface; the modification was found to decrease the dispersive component of the surface free energy of the solids. Acid-base interactions were evaluated by using polar probes according to the Lewis acid-Lewis base concepts. All pigments, including modified by silane coupling agents, had stronger interactions with the basic probe than with acidic one, demonstrating the very acidic nature of their surfaces.

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