The chemical compositions and electronic states of grain boundaries of some functional ceramics were analyzed by Auger electron spsctroscopy (AES), isothermal capacitance transient spectroscopy (ICTS) and other spectroscopic methods. In the case of ZnO varistors, the main additive Bi ions were segeregated at the grain boundaries with 2-3 nm thickness and produced oxygen deficiencys there. The secondary adiditive Mn was also concentrated highly in the grain boundary region, whose peculiar distribution suggested result in ZnO varistor having good nonlinear properties.
Thermal and photo ICTS signals of SiC ceramics doped with small amounts o f BeO were observed for the first time. From the analysis of ICTS signals, it was determined that the grain boundary interfacial state was located 0.9 eV above the valence band and it was found out that there was disorder of chemical bonding state caused from doping ionic bonding oxide BeO.
Auger transitions KL_{2, 3}L_{2, 3} for oxygen of ZnO varistors were calculated by a Discrete Variational Xα (DV-Xα) method. This result suggested that the metal-oxygen bonding state in the grain boundary changed with increased amounts of segregated Bi. The change of the bonding character was considered to be related to the formation of grain boundary interfacial state.

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The UV absorption spectrum of 1-methyl-2 (1H)-pyridinimine (abbreviated as MPI) has two bands at 253 and 350 nm in isooctane solution at room temperature, while these bands shift to 216 and 305 nm in methanol and ethanol solutions. This experimental result suggests that the molecular structure of MPI may be different from each other in isooctane and alcoholic solutions. In this paper, the UV and IR spectra of MPI were measured in aq. H₂SO₄, water and alcoholic solutions at room temperature in order to make clear the above considerations. The UV spectra of MPI in aq. H₂SO₄ solution were basically in good agreement with the corresponding ones in water and alcoholic solutions. The above experimental results suggest that MPI may become 1-methyl-2-aminopyridinium cation in water and alcoholic solutions like in aq. H₂SO₄. The IR spectra of MPI in aq. H₂SO₄, water and alcoholic solutions were supported by the calculated results of the previous normal coordinate treatments done on the model of 1methyl-2-aminopyridinium cation.

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The MC-LCAO-MO method, which is a semiempirical method with using the it π-electron approximation and has been proposed for predicting the molecular geometries and electronic structures of ope nshell systems of aromatic hydrocarbons having degenerate MO's, is applied to the geometry optimiza-ti on for five lower excited states of the molecules cited in the title, examining the Jahn-Teller effect in th ese electronic states. The applicability of the method is at first discussed by calculating the grou ndstate geometries and π-electron energies and the electronic spectra of these molecules; the results for th e ground-state π-electron energies and the electronic spectra are good compared with those derived from the usual SCF-CI method. The five excited states selected for examination are three lowest excited singlet states and two lowest excited triplet states. The common results obtained for these three molecules are that the molecular geometry in the lowest excited singlet state is not distorted to lower symmetry than the one in the ground state and that the lowest triplet state is subjected to the Jahn Teller effect and the resultant quinonoidal form is more stable than the antiquinonoidal one. For the second lowest excited singlet state, the Jahn-Teller distortion is suggested to occur in benzene and triphenylene, but the distortion is not found in coronene. For the degenerate electronic states in the symmetrical form, that is, for the third lowest excited singlet and the second lowest triplet states, the Jahn T eller effect is not very small in triphenylene, however the effect is distinctly small in benzene and not found in coronene.

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A paper chromatographic technique using fabric as the stationary phase was used to study the mechanism by which oily soils are removed from the substrate in a state almost without mechanical and/or hydrodynamic actions from the standpoint of surface and colloid chemistry. Using a cotton fabric, rayon fabric, polyester fabric, cellulose filter paper, and thin layer of fine crystal cellulose as the stationary phase for the substrate, the Rf'-values of oleic acid (OA) as a model of oily soil have been studied in sodium dodecyl sulfate (SDS) aq. solutions as a function of the concentration. In every substrate, the Rf'-value, a measure of the detergency, started to rise at a concentration of SDS significantly lower than its critical micelle concentration (cmc), which implies that the oily soil removal has begun at this low concentration. The Rf'-value increased with the increase in SDS concentration. The concentration necessary to increase the Rf'-value to 1 was 12 x 10-3 mol dm-3 SDS for polyester fabric and 7.0 x 10-3 mol d m-3 SDS for the other cellulose substrates. With these chromatographic observations, th e partition coefficients, K-values of the OA between the fiber and water and between the fiber and micelle have been determined. K-values for polyester are higher than that for cotton or rayon, which suggests that it is more difficult to remove OA from polyester. The removal of OA from a substrate largely occurs by a molecular complex formation between OA and SDS at a low concentration below the cmc, and by solubilization of OA into or around a micelle above the cmc. t Study of Soil RemovalM echanism Using a Chromatography Technique. I I.

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The kinetics of the homogeneous hydrogenation of styrene with a (1, 3-diphenyltriazenido)dihydridobis (triphenylphosphine) rhodium (III) (dihydridorhodium complex) -dimethylsulfwdde (DMSO)system was studied at 30 °C. For the hydrogenation rate, first order and zero order dependence was observed with respect to the concentration of the dihydridorhodium complex and the partial pressure of hydrogen, and to the styrene concentration, respectively. The steric factors of substituent on the double bond affected the activity of hydrogenation. The effect of para substituents of styrene on the rate of hydrogenation was investigated. Electron-withdrowing group on the para position of phenyl ring of styrene accelerated the rate of hydrogenation and electron-releasing group on the para position of phenyl ring of styrene decreased the hydrogenation rate. A linear relationship between the Hammett σ+ values of substituents and the relative rate of hydrogenation of styrene was obtained.

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Allylation of diethylamine or ammonia with allyl alcohol catalyzed by Pd (OAc₂)-diphosphine was investigated. Pd (OAc) ₂-dppb [dppb = 1, 4-bis (diphenylphosphino) butane] and -dpppe [dpppe =bis (diphenylphosphino) pentane] catalysts were found to be the most effective for such reactions, and the former catalyst also acted as an effective catalyst for reactions of various allylic alcohols with diethylamine. Propylene glycol was an appropriate solvent for these allylation reactions. A reaction mechanism including the oxidative addition of allyl alcohol to give a η-allylpalladium intermediate was proposed. The kinetic study for the reaction of allyl alcohol with diethylamine revealed that the reaction was the first-order concerning allyl alcohol, diethylamine and the palladium catalyst, and the apparent activation energy was 66 kJ/mol.

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Direct N-allylation of amides with allyl alcohol catalyzed by palladium complexes was investigated. In the reactions of carboxylic acid amides and ally! alcohol catalyzed by Pd (OAc)₂-dpPb [dPpb= 1, 4bis (diphenylphosphino)butane], the corresponding N-allylamides and N, N-diallylamides were obtamed in moderate to good yields, when a catalytic amount of PhONa was added to the reaction system. In contrast, N-allylation of sulfonamides with allyl alcohol underwent smoothly by the same catalyst in the absence of PhONa, and the corresponding N-allylsulfonamides and N, N-diallylsulfonamides were formed in high yields under neutral conditions.

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Single crystals of CrB were obtained by the reaction between chromium sesquioxide and amorphous boron powders at 1400 to 1700 °C for 2 h in a carbon crucible under an argon atmosphere (0.15 MPa). CrB single crystals were grown at 1600 to 1700 °C for 2 h with the molar ratio of starting material B/Cr₂0₃=3.0. The CrB crystals had maximum dimensions of about 3.3 mm x 0.6 mm x 0.6 mm and gr ew in the form of prismatic shape extending in the ‹001› direction of orthorhombic symmetry. As-grown CrB single crystals were subjected to chemical analysis and measurements of unit cell dimensions, Vickers microhardness and electrical resistivity. The results are as follows: Cr0.97B, a=0.29668 (7) nm, b=0.7868(2) nm, c=0.29309(9) nm, th=23.1(±0.8) GPa, p=32.0 (±0.2)

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Industrial production process of N-phenylmaleimide (PMI) was developed based on consideration of the reactions expected. It was found that 2-anilino-N-phenylsuccinimide (APSI) was converted to Nphenyl-N-(1-pheny1-2, 5-dioxo-3-pyrrolidinyl) maleamic acid (PPMA) by reaction with MAN and that PPMA was thermally decomposed to PMI to increase the yield of PMI. As a result, following improvements for the production process were achieved using the catalyst consisting of an acid and acid anilinium salt.1) PMI is found to be produced from aniline and maleic anhydride directly.2) Catalyst is easily separated from the organic layer by changing molar ratio of aniline to maleic anhydride.3) The catalyst is readily separated after the reaction and can be reused to the subsequent reactions.

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A new supported catalyst system was proposed to produce N-phenylmaleimide (PMI) from Nphenylmaleamic acid (PMA) in an improved yield. Followings are important factors to affect the yield of PMI according to consideration of the details of dehydration process of PMA. 1) Interfacial area between the organic solvent phase and the catalyst phase. 2) Thickness of the catalyst phase. 3) Agitation. The supported catalyst improved considerably the yield of PMI under optimum conditons for 1) and 2). It was proved that a suppress of the hydrolysis of PMA in former half of the reaction brought about the high yield.

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In general, the reactions of t-alkyl halides with alkali metal alkoxides and phenoxides in polar solvents give olefins (E) almost alone. However, we found a new method for the preparation of t-alkyl ethers (S_N) in the reactions of t-alkyl substrates with metal alkoxides and aryl oxides in nonpolar solvents. Alkali metal phenoxides (PhO^- M⁺; M⁺=Li⁺, Na⁺ and K⁺) reacted with t-butyl bromide and iodide in hexane at 60 °C for few hours to give t-butyl phenyl ether in 41-59% yields. A similar S_N reaction of alkaline earth metal phenoxides also gave the ether in 54-60% yields. More hindered 1-adamantyl methanesulfonate, which is resistant to elimination compared with t-butyl halide, reacted with metal alkoxides in octane at 100-110 °C to give corresponding 1-adamantyl alkyl ethers in good yields. The comparable reaction of 1-adamantyl iodide was much slower than the case of 1-adamantyl methanesulfonate. Aprotic polar solvents (DMF, DMSO) were unfavorable for the S_N reaction. On the other hand, alkali metal alkoxides reacted with t-butyl halide in heptane to give 2-methylpropene (E) exclusively, but strontium and barium alkoxides gave 15-50% of alkyl t-butyl ether (S_N) at 80-95 °C. The selectivity of S_N/E was governed by solvent, metal cation (Li⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺), nucleophile, and substrate. The nonpolar solvents were much more effective than polar solvents for the SN reaction. The addition of crown ether to the system decreased markedly the S_N/E ratio. The addition effect of radical scavenger, galvinoxyl was not recognized.

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Crystalline CdS thin films doped with Cu were deposited on a glass substrate by chemical bath method. In order to prepare the homogeneous films on the substrate, the addition of triethanolamine (tea) together with ammonia into cadmium acetate solution was necessary. The CdS films obtained were found to consist of minute crystals parpendicular to the surface (Fig.3). The morphology of the films surface changed to the aggregation of island-like particles on the substrate with the increase of Cu content (Fig.5). The crystal structure of the films obtained was found to be a mixture of zinc blende type and a small amount of wurtzite type (Fig.7). The electrical conductivity and the mobility of the films increased with the increase of Cu dopant under dark and visible light irradiation, and the maximum value of the electrical conductivity showed about 80.8 S/cm at 8 mol%Cu. Under ultraviolet radiation, however, it was found that the electrical conductivity and the mobility decreased with the increase of addition of Cu. The carrier concentration was constant (1.3 x 10²² cm^-3), in spite of the addition of Cu dopant and the irradiation of light (Table 1).

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The synthetic reaction of trioxane from formalin on the zeolite catalysts was studied.
High catalytic activities were observed over high silica zeolite with Si0₂/Al₂0₃ ratios gr eater than 15, especially more than 25. This result became clear that an indispensable condition of developing the activity was the hydrophobic nature of high silica zeolite in the aqueous solution reaction.
On the ZSM-5 zeolite with 20 μm of large particle diameter, the selectivity of trioxane showed low value and formic acid and methyl formate were produced as by-products. However, the selectivity drastically increased with decreasing the particle diameter.
The poison experiment of ZSM-5 by organic base proved the active site of this reaction was the acid site of only inside of pore and not outside of one.
When the selectivities of various kinds of z eolites were compared, high selectivities were observed over mordenite and β-zeolite with pore of 12-membered oxygen ring and low one and the formation of a lot of formic acid and methyl formate over ZSM-5 and ZSM-35 zeolites with pore of 10-membered oxygen ring.
The fine particle of ZSM-5 with 10-membered oxygen ring and zeolite with 12-membered one were profitable to the diffusion of trioxane with the large molecular size because of the shape selectivity of the zeolite which made the difference of selectivity in the particle size of ZSM-5 and a type of zeolite.
It was confirmed by the results of the life test of catalyst, β-zeolite and ion exchange resins, for 500 h that β-zeolite showed more stability to heat and longer life than ion exchange resins.

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Fourier transform infrared (FT-IR) spectra were measured for 2, 2'-bipyridine (bpy) adsorbed on silver fine particles derived from colloid and bis (2, 2'-bipyridine) silver ( I ) nitrate ([Ag^I(bpy)₂]NO₃) by using an attenuation total reflection (ATR) prism. The surface enhanced infrared spectra of bpy showed drastic changes in the intensities of bands due to ring stretching vibrations and CH bending vibrations. This suggests that the adsorbed molecules on silver particles take a co nformational change and the intramolecular charge-transfer, which are different from those of the crystal.

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The oxidative dehydrogenation of isobutyric acid has been investigated using the heteropolymolybdophosphoric acid (HPMo) catalyst supported on the SiO₂ modified with (3-anilinopropyl)trimethoxysilane (AnPS) as silane coupling agent. HPMo fixed on the modified SiO₂ indicated extremely higher conversion of isobutyric acid and selectivity to methacrylic acid at 250-300°C than the unmodified catalyst.

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Dealumination rate of HZSM-5 zeolite under various water vapor pressures was investigated by means of ²⁷ Al MAS NMR. The dealumination rate was markedly dependent on the water vapor pressure. Under water vapor pressure ranging from 0.1 to 1 kg/cm², it was found that the dealumination rate was apparently third-order dependent on the content of framework aluminum and approximately 1.5-order dependent on water vapor pressure. Based on these results, a plausible mechanism of dealumination of HZSM-5 zeolite by steaming was proposed.

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Synthetic expandable fluorine mica having layer charge of 0.5 [Na_0.5Mg_2.5Li_0.5Si₄O₁₀F₂] was reacted with concentrated hydroxoaluminum solution containing highly polymerized species of hydroxoaluminum polycations, which had six or eighteen times larger volumes than ordinary Al₁₃-polycation having Keggin structure. Thermal durability of the complexes thus obtained from concentrated hydroxoaluminum solution was higher than that obtained from ordinary Ai₁₃-polycation while microporous characters vanished for the former complexes, e., alumina pillared fluorine micas. The increase in thermal durability and vanishment of microporous characters probably resulted from the stuffed structure of intercalated bulky hydroxoaluminum polycations having larger polymerization degree as well as the highest value of intercalated Al-content of 2.30 mol/Si₄O₁₀.

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The isocyanate-terminated urethane prepolymer(ITUP) based ondiphenylmethane-4, 4'-diisocyanate and polyether ssuch as poly(oxypropylene) α, ω-diol and poly(oxytetramethylene) α, ω-diol of various moleculer weights was characterized with regard to moleculer weight distribution, T_g, viscosity and hydrogen bond of urethane linkage. This report relatesta the effect of chemical struture of palyethers on the characteristics of ITUP.

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