Conditions for preparation of ZrO₂ monodispersed particle from zirconium soaps suspended in higher alcohols were studied. Linear fatty acids of C₁₂, C₁₄, C₁₆ and C₁₈ were used for preparation of metal soaps. Higher alchols of C₈, C₁₀, C₁₂ and C₁₄ were used as the dispersion media. The stable organosols containing ZrO₂ particles were obtained from the zirconium soap suspension at 120-200°C.
The dispersion sta te and the mean particle radius obtained were dependent on the heating temperature and the carbon numbers of the metal soaps: The particles are more monodispersed at the higher heating temperature and they have the smaller mean particle radius with increase of the carbon chain numbers of the metal soaps.

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Visible absorption spectra were measured for an α-Al₂O₃ Powder/NiC₂ po wder and NiCl₂ aqueous solution coexisting system. The VIS spectra of the system deformed from that of the aqueous solution. The absorption bands at 25.3 x 10³cm^-1, assigned to ³A_2g→³T_1g, transition of Ni(II)octahedral complex, were shifted toward low wavenumbers and the intensity of the band for Ni(II) tetrahedral complex increased with the increases of the solid content and the spec ific surface area of α-Al₂O₃ Powder/NiC₂ powder. It is suggested that the liquid phase, affected by the solid phase, has the coordination structure similar to that in the concentrated solution. The intensity ratio of the absorption band of Ni(II) tetrahedral complex to that of octahedral complex increased with the increases of the solid content and the specific surface area of the solid phase and clearly correlated with the apparent average thickness (=[total volume of liquid phase]/[surface area of solid phase]) of the vicinal liquid layer. The restricted liquid layer has ca. 20-30nm of thickness above the surface of the solid phase.

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The catalytic exchange reactions of oxygen between ac etone and water on copper oxide (CuO) was studied using ¹⁸O as a tracer, in the range of 50-100 °C. In addition, the adsorption isotherms of acetone and water on CuO at 50 °C and 100 °C were measured in order to study the relation between acetone and water on the catalyst.
It was found that the exchange reactions of oxygen between acetone and ¹⁸O-water proceeded rapidly on CuO and oxygen-treated Cu metal, but not on reduced Cu metal. Also, it was found that the oxygen of CuO were slightly exchanged with the oxygen of water but not with that of acetone.
Also, the amoun ts of adsorption of water were about 1.5-2 times larger than those of acetone.
From these results, it was proposed that the exchange of oxygen between acetone and water on CuO occurred by rapid progress of hydration and dehydration of acetone on surface layer of CHO.

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In the present work, 27 kinds of metal oxides were employed as catalysts for the decomposition of sodium chlorate. Using the TPR (Temperature Programmed Reaction) method, we observed the decomposition temperature of sodium chlorate. One of the most effective metal oxide was prone to be nickel oxide. From the DTA (Differential Thermal Analysis)measurement, it was found that addition of metal oxides to sodium chlorate lowered the decomposition temperature to some extent, though the melting temperature did not change. Thus, the metal oxides added work as catalysts for the decomposition of the molten sodium chlorate, resulting in oxygen evolution at lower temperature.
We discussed about the reaction mechanism betwe en the metal oxides and sodium chlorate. As the temperature rises, the hopping electrons are generated at the surface of the metal oxides, then the positive holes are formed. The chlorate ions are drawn toward the holes to be oxidized to perchlorate ions, which yield to sodium chloride and oxygen at the successive step. Thus, the decomposition temperature of sodium chlorate depends upon the activation energy of hopping electrons in the metal oxides.

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ACFs which had been saturated with adsorbed ammonia were regenerated with NO (400ppm) in air at room temperature. NO in air was very effective to recover the adsorption ability of ACFs to 40-90% of that obtained after the standard regeneration at 185 °C by air flow. Recovery rate decreased in the order of pitch-based, PAN-based and phenol resin based ACFs. Humidity in air above 80% disturbed severely the regeneration, 100% of humidity decreasing the abilities after the regenration to 0 to 10% of those after the standard regeneration. Pitch-based ACF was least disturbed. High regeneration temperature enhanced the regeneration with NO even in the humid air. The reactivity of adsorbed ammonia on ACF with NO in air is discussed in relation with the regeneration. Humidity in air may influence the adsorption and reactivity of NO in connection with surface properties of ACFs.

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Magnetite was prepared from the mixed solution of FeCl₂·4H₂O and FeCl₃·6H₂O utilizing the hydrolysis of urea. The ultrafine particles of magnetite were prepared by addition of sodium dodecyl sulfate (SDS) as anion surface active agent into the above mixed solution. The effects of amount of SDS on the particle size were investigated. In the initial stage of the reaction, β-FeO(OH) was obtained by hydrolysis of Fe³⁺ ions and it was transformed to Fe₃O₄ at pH 5.0. The particles were obtained as the suspended solution in water base, sinc e their surfaces were protected by SDS. A part of the ultrafine particles was separated by centrifuzing at 15000 rpm for 3 h and dried in a vacuum desiccator at room temperature. The SDS content of the ultrafine particles obtained was about 15.9 wt%, magnetic susceptibility was 30.5 emu/g and coercive force was 0.96 Oe. The size of the ultrafine particles was ranged from 30 nm to 80 nm (average size 50 nm). The ultrafine particles of magnetite was easily prepared and the magnetic fluid of water base was prepared by condensing or by centrifuzing the reaction solution at one step operation.

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Two series of macroreticular resins having 1-oxoalkyl and 1-hydroxyalkyl groups were prepared and their adsorption behavior of dodecylbenzenesulfonate (DBS) was investigated by the batch operation. Although the specific surface areas of the both types of the resins were somewhat similar or smaller than that of the starting styrene-divinylbenzene resin (7.5 V%divinylbenzene), the adsorption capacities for DBS were markedly increased with the introduction of the functional groups. The resins having the shortest alkyl chain (P-COCH₃, PCH(OH)CH₃) showed the highest adsorption capacity among the resins in each type of the resin. The increase of the capacity was observed in the presence of sodium chloride, but the presence of methanol strongly reduced the adsorption.
More than 95% of the DBS adsorbed on a column of the modified resins could be recovered with ethanol. Applicability of these resins for pre-concentration of linear alkylbenzenesulfonate in environmental specimen was also examined.

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Halogenation of 1, 8-dimethylisoquinline 1 and 5, 6-dihydro-4H-benz[de]isoquinoline 2with halogen in the presence of silver sulfate and with N-halosuccinimide was investigated. On the halogenation with halogen in the presence of silver sulfate, the compound 1 gave 5-bromo-1, 8-dimethylisoquinoline 3 a, 5, 7-dibromo-1, 8-dimethylisoquinoline 3 b and 5-iodo1, 8-dimethylisoquinoline 4, while the compound 2 gave 9-bromo-5, 6-dihydro-4H-benz[de]isoquinoline 5. Halogenation of 1 with N-bromosuccinimide also produced 3 a, and the chlorination of 1 with N-chlorosuccinimide gave 5-chloro-1, 8-dimethylisoquinoline 6.

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Further studies on synthetic use of N-vinylimides, which have the chemical structure of enimide type, are reported.
It was disclosed th at 3-phthalimido-2-propenal, its derivatives and related compounds reacted with various active methyl and active methylene compounds to produce pentamethinecyanines and imido-substituted polymethinecyanine-like compounds.

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Dimethyl N-[(cyanoimino)ethoxymethyl]carbonimidodithioate 3 was prepared by the reaction of 3-cyano-2-ethylisourea with carbon disulfide in the presence of potassium hydroxide, followed by methylation with methyl iodide.3 was reactive and yielded 3-cyano-1-[(disubstituted amino)methylthiomethylene]-2-ethylisourea 8 on reaction with secondary amine, and 1-substituted 4-ethoxy-6-methylthio-1, 3, 5-triazin-2(1 H)-imine 9 with primary amine.9 reacted with amine hydrochloride to give mainly 1-substituted 6-(substituted imin o)-4ethoxy-3, 6-dihydro-1, 3, 5-triazin-2(1 H)-imine 10 salt, whereas 1-substituted 4-(substituted imino)-6-methylthio-3, 4-dihydro-1, 3, 5-triazin-2(1 H)-imine 11 salt was obtained in some cases of 9 having bulky 1-substituent.1-Substituted 4, 6-bis(substituted imino)-3, 4, 5, 6tetrahydro-1, 3, 5-triazin-2(1 H)-imine 12 salt was prepared by the reaction of 3, 9 or 10salt with amine and/or amine salt.

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Effect of solutes on a polyion complex type multibilayer film prepared from quaternary ammonium amphiphiles ([CH₃(CH₂)_n-1]₂N⁺ (CH₃)₂, (n=16, 18)) and poly (styrenesulfonate)was studied by dynamic viscoelastic measurements in water. Modulus of elasticity of the films was decreased by the sorption of organic solutes owing to changes in physical properties of bilayer structures in the film. With increasing the hydrophobicity of solutes, their effect on the modulus of elasticity increased. The magnitude of the effect was also affected by an electrostatic interaction between the solutes and the cationic amphiphiles in the film, and the molecular shape of solutes. Salts decreased the modulus of elasticity due to the ionic interaction between the polyion complex and salts.

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ZrO₂-Y₂O₃ coating films have been prepared from zirconium tetrabutoxide and yttrium (III)nitrate by the sol-gel method. In order to be employed for coatings, the concentration of the partially hydrolyzed products was increased 4 to 7 times the initial concentration. The alkoxide reacted with yttrium nitrate to form a powder of ZrO₂-8 mol% Y₂O₃ when the sols were dried and then heated at 1100 °C for 2 h. The concentrated sols retained clearness for a period longer than 60 d when they were repeatedly stirred in a closed system.
The films showed various colors depending upon the film thickness. The sample, after heating at 440 °C in vacuo, gave a sharp absorption band due to Zr-O-Zr bond in the FT-IR spectrum. A depth profile of the film on a stainless steel plate was obtained by secondary ion mass spectrometry, and an interdiffusion phenomenon at the film-substrate was found.

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Effect of temperature and humidity on the adhesion of iron pow der onto melamine-cured coating film was discussed. Iron powder adhesion occurred under high temperature and humidity. From the result of the observation of the coating film section with a microscope, it was found that the film was not stuck by iron powder, but the powder adhered on the film surface.
The relation between iron powder adhesion and the moisture permeability of film was discussed for the top-coat. From the result it was found that iron powder adheres easily to coating film having high moisture permeability. Moisture permeability was affected by the cross-linking density of film, and the film with lower cross-linking density resulted in much adhesion of iron powder.
It was thought that iron powder adhesion occurred by the penetration of Fe(OH)₃ aqueous solution to coating film under high temperature and humidity.

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To know the dyeing mechanism of polyester fibers with disperse azo dyes, the contribution of hydrogen bonding between alcohols and the dyes was investigated by the visible absorption spectra using the modified McRae's equation. The formation of hydrogen bonding was confirmed by infrared absorption spectra of the azo dye model-alcohol system in carbon tetrachloride.
It was found that alcohols acts as a proton donor and dyes as a proton accepter. The hypsochromic shift of the λ_max in alcohols due to hydrogen bonding was found to be 100-500cm^-1. The bond energy between ethanol and the dyes was 0.2-1 kcal/mol which wa s about 3-9% of the total dye-ethanol interactions. A very little degree of contribution was found for hydrogen bonding in the interactions between disperse azo dyes and methyl benzoate or poly(ethylene terephthalate) film (PET).

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The chemical forms of pH and metallochromic indicators adsorbed onto porous Vycor glass are determined by visible absorption spectroscopy.
Methyl Red is adsorbed on porous Vycor glass in a red protonated form. A proton is donated from the active silanol residue on the surface of porous glass to the nitrogen atom of Methyl Red, leading to formation of a hydrogen bonding. Xylenol Orange is adsorbed on porous glass from an aqueous solution in a manner similar to the coordination to a metal ion as a metallochromic indicator. On adsorption, the proton of the phenol residue of the Xylenol Orange is dissociated and the imino and carboxyl groups play a role in adsorption as binding sites to the silanol group of porous glass. The adsorbed Xylenol Orange is exchanged by EDTA, dissolving into solution. It also reacts with copper(II) ion, forming a complex soluble in water.

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Three kinds of 4-t-butyl-1-alkylidene (methylene-, ethylidene- and isopropylidene)cyclohexane were hydrogenated over the group 8-10 transition metal catalysts. The ratios of the stereoisomeric products over Co and Ni catalysts were different from over other noble metal catalysts but the ratios of the trans to the cis products over every catalyst tend to increase with increase of methyl substituents of the C=C double bond. These results are discussed in terms of the intramolecular steric interaction in the adsorption state of substrates. The stereochemistry of 4-t-butyl-1-methylene- and ethylidenecyclohexane by hydroboration and oxymercuration was also examined.

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Magnesium oxides doped with small amounts of nickel (Ni/MgO) have been examined as a reforming catalyst for moderate-temperature fuel cell systems. The activity and the selectivity for the catalytic decomposition of methanol to hydrogen and carbon monoxide (H₂+CO) were studied in a flow reactor at a temperature range of 250-600 °C. The activity of the catalysts increased with increasing the nickel loading. Th reaction selectivity to H₂+CO was much improved by doping nickel. The Ni/MgO catalyst (5 wt% Ni) showed a selectivity as high as about 96% at the reaction temperature of 550 °C.

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The Fries rearrangement of phenyl 1-naphthoate 1 and 2-naphthoate 2 in chlorobenzene at reflux temperature led to the formation of 2- and 4-hydroxyphenyl ketones (3 and 4 from 1 and 5 and 6 from 2). Compound 1 rearranged more readily than compound 2 did. The olp ratios of the rearrangement products were O.4 4 for 3/4 and 0.95 for 5/6, respectively, after 2 h. The both ratios aproached O.57 after 8 h.
When 1 or 2 was heated in toluene in the prese nce of AlCl₃, cross-over products, tolyl ketones 9 and 10 or 11 and 12, were detected in the reaction mixtures. The results suggest that the Fries rearrangement of 1 proceeds almost intramolecularly, while that of 2 does interand intramolecularly.

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In an equimolar reaction of benzhydrol 1 with DMSO-SbCl₅(1:1) complex, dibenzhydryl ether 2 and benzophenones 3 formed. The derivatives of 2 and 3 were found in the reaction of some benzhydrols with the complex (Table 1). When the molar ratio (Complex/1) increased, the products ratio (3/2) became higher (Fig.1).
An equilibrium between benzhydrols and dibenz hydryl ethers is in existance in the presence of complex (Table 2), but no production of 2 was found in the reaction 3 with complex.
The yield of the reaction products, dibenzhydryl ethers and benzophe nones, in the reaction of para-substituted benzhydrols with the complex became higher in the following order CH₃>Cl>NO₂. The role of the complex in these reaction seems to be a proton acceptor from 1 in first stage.

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